GULF RESEARCH REPORTS Vol. 6, No. 2 December 1978 ISSN: 0072-9027 Published by the GULF COAST RESEARCH LABORATORY Ocean Springs, Mississippi I Gulf Research Reports Volume 6 | Issue 2 January 1978 Activities of the Gulf Coast Research Laboratory During Fiscal Year 1 977-78: A Summary Report Harold D. Howse Gulf Coast Research Laboratory DOI; 10.18785/grr.0602.13 Follow this and additional works at: http:/ / aquila.usm.edu/ gcr Recommended Citation HowsC; H. D. 1978. Activities of the Gulf Coast Research Laboratory During Fiscal Year 1977-78: A Summary Report. Gulf Research Reports 6 (2): 189-208. Retrieved from http:// aquila.usm.edu/gcr/vol6/iss2/13 This Editorial is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf and Caribbean Research by an authorized editor ofThe Aquila Digital Community. For more information, please contact Joshua.Cromwell^usm.edu. Gulf Research Reports. Vol. 6, No. 2, 189-208, 1978 ACTIVITIES OF THE GULF COAST RESEARCH LABORATORY DURING FISCAL YEAR 1977-78: A SUMMARY REPORT HAROLD D. HOWSE Director. Gulf Coast Research Laboratory, Ocean Springs, Mississippi 39564 ADMINISTRATION During the year, the Gulf Coast Research Laboratory (GCRL) was llie recipient of several significanl gifts. These were the following; a 26-foot LafitLe skiff, powered by a 6'Cylinder, 135-horsepower Palmer engine, valued at $7,000 and donated by Mr. Cyril R, Laan of Ocean Springs and New Orleans; 33 acres of Sioux Bayou marsh lands valued at $11,000 and donated by Tri-Land Development, Inc., Pascagoula; and a small wooden building valued at $10,000 from Keesler Air Force Base donated by the U.S. Department of Health, Education and Welfare. Additionally, two and one-half acres of properly adjaceni to the campus was pur- chased, including a small, wood-frame house. The annual State appropriation for the general support of the Laboratory was $1,780,500. An additional $25,000 was received through a Special Library Improvement Allo- cation by the 1977 State Legislature and $672,468 was generated through sponsored research. BOAT OPERATIONS The boats that provide essential services include the 65-foot R/V GULF RESEARCHER, used in both the Laboratoiy’s research and educational programs; the 38- foot steel trawler HERMES, used principally in the educational program; three diesel-powered cabin work- boats; and some half-dozen Boston Whalers and other miscellaneous smaller boats operated on a part-time basis by scientists and technicians to meet the needs of Labor- atory research projects. During the year ended June 30, 1978, R/V GULF RESEARCHER was at sea for 61 days and 24 nights. HERMES spent 59 days at sea and the smaller boats made innumerable trips over the same period. RESEARCH ANADROMOUS FISHES SECTION, Dr. Thomas D. Mdlwain. Head Rearing and Stocking Striped Bass - Mississippi Gulf Coast (Funded by National Marine Fisheries Services [NMFS] , U.S. Fish and Wildlife Service and GCRL): The second seg- ment of the project dealing with the rearing and stocking of striped bass was begun in September 1977. The objectives of this program arc to establish, by stocking, a striped bass population in Biloxi Bay; to stock sea-run striped bass and determine their success; and to establish a source of fry from Mississippi brood fish. Approximately 582,000 striped bass of South Carolina origin were reared to a size of 2 inches and stocked into Biloxi Bay. Some 145,400 of these fish were reared from eggs taken from Mississippi brood I'ish. These brood fish were taken front Pearl River near Jackson, Mississippi, by Mississippi Game and Fish Commission (MGFC) personnel and transported to GCRL for spawning. Out of eight eligible females, four were tank spawned, three successfully. The successful spawn resulted in 1.7 million fry. One million were returned to MGFC for rearing and the remaining 700,000 were retained at GCRL for rearing. No sea-run striped bass were stocked in this segment due to the unavailability of fry from sea-run slocks. A total of 66 striped bass which were slocked in previous years were returned to project personnel. These fish ranged in weight from one-half pound to 19 pounds. A sampling program is in progress to check for natural reproduction of previously stocked bass and for occurrence of juvenile striped bass, and to monitor previously slocked striped bass in order In continue assessing the results of all bass-stocking programs previously carried out in this area. Bait Fish Rearing (Funded by Mississippi Marine Resources Council [MMRCJ): A handbook was developed detailing the techniques for rearing bullminnows in closed systems and in ponds to supply the live-bait industry along the coast. The bullminnow is a favorite live-bait wlien available to coastal sport fishermen. Supplies are quickly depleted in lale fall when the spotted seatrout (Cynoscion nebuhsus) are running. Sporting Analysis of St. Louis Bay (Funded by E. 1. duPont de Nemours & Company, Inc. (Du Pont]): This program began in December 1977 and will continue for one year. The work entails gathering data on the total effort expended and total harvest of sport fish caught in St. Louis Bay. Data gathered will detail species composition, seasonal and nun.erical abundance, as well as size composition and method of capture and catch per unit of effort. A Proposed Mississippi Marine Fin fish (Selected) Fishery Management Plan (Funded by Mississippi-Alabaina Sea Grant Program [M-ASGP] ); As one of the five Gulf of Mexico states, Mississippi plays an integral role in the Gulf slates fisheries. With a shoreline of only 70 miles, Mississippi ranks second in the total volume of seafood landed in these five states. Because of increasing national and international emphasis on fisheries and fishery management plans being developed, it has become more and more important for the 189 190 HOWSE slates to improve their management technique in this area. In essence, the states are the key to the regional and national success of our fisheries from all standpoints— biological, economic, social, environmental, administrative, etc. An improved finfish management system in Mississippi will not only improve the Mississippi output and conservation of the resource, but will contribute to improving both the Gulf regional fishery and the national fishery. A carefully devel- oped and organized management plan for Mississippi does not exist at this time. ANAL YTICAL CHEMISTR Y SECTION, Dr. Viotnas F. Lyile, Head Heavy Metals in St, Louis Bay (Funded by Du Pont): Because heavy metals pose a potential threat to estuarine water, whether coastal areas are developed industrially or residentially, an assessment of heavy metals is being con- ducted in St. Louis Bay where very little of cither type development exists. Heavy metals are being examined in as many of the environmental components of the bay as pos- sible. Because heavy metals may exist in the water column cither in the soluble form or as particulate, both forms are being analyzed. The eventual repository for heavy metals is the sedimentary bed; sediments which will reflect a combined history of heavy metal input for asionga period as sampling will allow are good candidates for monitoring past exposure to heavy metals. Organisms may concentrate heavy metals either by absorption or ingestion from water or sediments. These concentrations may escalate to levels that are harmful to the organism, to its predator or man. The concentralion of heavy metals in the tissuesoforganisms does not fluctuate quite, so drastically as in the water nor remain as stable as in the sediments. However, because any grossly elevated levels of heavy metals would be of more immediate harm to organisms than to sediments, we need to know more about the heavy metal budget in the Bay. A survey, to adequately describe heavy metals in bay waters, should include a constant monitoring of metals in many locations for a period of several years. This approach is presently not feasible even on a small scale; therefore, we must be satisfied to collect water samples that will give at least typical values for the Bay. Eight stations have been selected for heavy metal collections from among 11 stations used for nutrient studies. These stations are being occupied once every second month for the purpose of making a collection sufficiently large to measure the following 17 metals: copper, chromium, cobalt, nickel, zinc, cadmium, iron, titanium, vanadium, mercury, arsenic, selenium, antimony, strontium, molybdenum, beryllium, and lead, plus cyanide. Ihe sampling does not coincide with any other sampling effort in order to avoid any contamination from the research boats in the Bay. The samples have been filtered, preserved and frozen, then transported to the Laboratory for analysis. Sediments from these eight stationsand six more have also been collected. An assortment of resident species of fish and invertebrates are being collected for dissection and analysis. Marsh soils and plants will also be analyzed. Of prime concern has been the construction of a ^‘clean” laboratory for trace metal analysis. All metallic objects were removed if feasible, and ifnot, coated with epoxy. Separated from the hall by an outer office, the clean area was sealed with epoxy paints and other plastic sealants and is supplied with constant, positive-pressure, ultrafiltered air. A Teflon- clean bench-hood for critical sample treatments and a fused- quaftz still for final water distillations were installed. Ceiling tiles were replaced with plastic panels cemented in place. Since debris from corroded surfaces or dust from any source could seriously compromise trace metal results, all efforts are being made to prevent these from occurring in the laboratory. When analyses are complete, the present load of heavy metals in St, Louis Bay should be known with a fair degree of certainty. Nutrients in St. Louis Bay (Funded by Du Pont); A pro- gram was designed to determine the levels and distribution of nutrients in St. Louis Bay. Later it was decided that the term nutrients was misleading; therefore, the measurements are now referred to as water quality parameters (WQP). Envisioned originally as measurements to support other studies in the Bay, this concept was soon abandoned because of the difficulties of coordinating all possible interests with the WQP samples. Because it appeared that productivity measurements would suffer most from lack of synopticity with that collection, samples for WQP were collected in a manner to achieve results that might be directly correlated. The parameters chosen were: orthophosphate, total phos- phorus, nitrate, nit rite, ammonia, chloride, sulfate, suspended solids, turbidity, alkalinity and silica. In addition, samples were also collected for total inorganic and organic carbon and distributed to the Environmental Chemistry Section. The methods used for analysis were those in the Federal Register, December 1976. Though these methods have proved defective in .some respects, matrix modifications in samples and standards have almost without exception proven them to be reliable. The only measurement remaining an enigma is that of total phosphorus. Water samples are collected once monthly in a manner to preserve the integrity of the samples for all WQP. Initially, samples for all param- eters were collected and preserved individually. However, this procedure proved very time-consuming and inept. Therefore, to collect samples as quickly as possible (to remove the time factor in station comparisons), one sample bottle is now used for all parameters. These samples, pre- served on ice, are rushed back to the Water Analysis Labor- atory for processing. This sampling procedure has worked belter than a field-based procedure. Eleven stations are sampled in this study including some in the Bay proper, others near residential areas, in large bayous and both the Jourdan and Wolfe rivers. Surface samples are collected at all stations each month; in addition, at half of the stations, vertical profiles of water quality parameters A Summary Report 191 are made when depths pennit. Correlations of the various parameters are being made; nutrient budgets are being estab- lished and overall water quality evaluated in St. Louis Bay. Techniques Development for OH Pollution Assessment (Funded by GCRL and the Bureau of Land Management); This is a continued study designed to find the best procedures both to chemically analyze geological and biological samples and to assess the proper parameters by which to designate whether or not the samples are polluted with petroleum hydrocarbons. Sediment samples, taken before emplacement, during drilling and after drilling, were collected from 25 strategic locations at a Texas oil rig site chosen by the Bureau of Land Management. These unique sampling and analyses offered enougli hydrocarbon data to apply various computer programming techniques to ascertain the most effective parameters in assessing oil pollution. BOTANY SECTION, Dr. Lionel N. Eleuterius, Head Salt Marsh Vegetation of Davis Bay (Funded by GCRL): Quantitative information is being accumulated on the rela- tionship of marsh acreage versus open water in this produc- tive estuarine system. In addition, the total area drained by the marsh and the amount of rainfall will be determined in order to study an entire estuarine ecosystem from the plant ecology viewpoint. A detailed vegetative map is being pre- pared as well as a map of the standing crop of all marshes surrounding Davis Bay. This information is basic to further detailed botanical and ecological .studies in the area around GCRLand should provide information for students, scientists and others within the State. Popiilational Studies on Salt Marsh Species (Funded by GCRL); This ongoing research is presently concentrated on the salt marsh rush,7w«cw.? rnenierUmus. Considerable popu- lation infoinialion has been gathered on the species and a portion of it is now In manuscript form. The ultimate goal is to document the distribution and the vegetative growth pattern of the major salt marsh species inhabiting the tidal marshes in Mississippi. Such popiilational studies are of considerable importance in relation to ecological work since ecotypes (single sexes) may dominate or compose large tracts of tidal marsh. Similar work has been imtiated on Scirpus olneyi and Distichlis spicata. Ecological Studies on Seagrasses and Sait Marsh Species (Funded by GCRL); Ecological studies on salt marsh species will entail synccoiogica! studies where more than one species compose the vegetation. Included in this study is consider- ation of the hydraulic aspects of flooding of various salt marsh zones to be done in cooperation with the Physical Oceanography Section. Grand Bayou, a high-salinity marsh dominated hyjuncus romerianus on Deer Island, Mississippi, has been tentatively selected for this portion of the study. Studies of other ecological aspects of this tidal marsh have been initiated. Tidal inundation and discharge rales can be easily established because of the smalU contained ecosystem represented in Grand Bayou. Quantitative data on plant productivity and the nutritive discharge of detritus and other water quality parameters will be assessed on the discharge and on the rising tide. Autecological Studies on Vascular Plants of Mississippi Salt Marshes (Funded by GCRL): This project is essentially an extension of population studies in that ecological param- eters such as soil nutrients, soil-water salinity, elevation, other chemical and physical aspects of the habitats (i.e., soil texture, evaporation), and the life history of the plants will be considered. Progeny and Genetic Studies on the Salt Marsh Rush, Jurtcus roemeriarms (Funded by GCRL); This work is ongoing research that has been carried out over a number of years. Plants have been grown for several years from seed to obtain Mcndelian ratios establishing the genetic mechanism responsible for the sexual distribution found in this rush species. The work constitutes an effort to obtain basic infor- mation on this species which dominates Mississippi marshes. During the past year, controlled cro.sses between known- parental types have been achieved and their seeds are presently being germinated. Hopefully, they will produce mature plants in less than the 2 years required under field conditions. An apparatus has been constructed in the greenhouse that will extend or shorten the day to induce flowering. Also, experiments have been conducted dealing with the physiological requirement of a cold period, known as verna- lization, to induce llowcring in this rush. If flowering can be induced, the growthand flowering cycle can be accelerated. An Illustrated Guide and Key to Salt Marsh Plants (Funded by M-.ASGP and GCRL); The purpose of this work is to prepare an illustrated guide and key to the salt marsh plants of Mississippi. It entails about 180 line drawings and scientific descriptions of local species of vascular plants. Keys to families, genera and species are being prepared. A Phytosociological Study of Horn and Petit Rois Islands (Funded by National Park Service, U.S. Department of Interior): During the First year of this two-year study, a large number of exclosurcs were established to assess the effect of animals such as nutria, hogs, and rabbits on the vegetation. Concurrently, phytosociological sampling was initiated to obtain information on community composition and successional patterns and interrelationships between the plant communities on these islands. Major products resulting from the work will be maps of large format that will accommodate many detailed vegetal ional features of Petit Bois and Horn islands. Hopefully, these will be pre- pared in color. Such color preparations will be of consid- erable value in the proper management of the islands and invaluable as baseline data for future scientific studies. Considerable effort has been made to obtain information on insular marshes which will be part of general ecological studies on salt marshes in Mississippi. A detailed report, pointing out the special features of these islands, is in preparation. 192 Howse St. Louis Bay - Botanical Survey and Plant Ecology of Salt Marshes and Submerged Meadows (Funded by Du Pont): Vegetaiional and community-composition mapping of salt marshes and submerged grass beds as documentation of standing crop, annual production and chemical characteri- zation of indicator plants and associated soils is in progress as part of a baseline environmental study. Continuous recordingsof soil-water salinity (isohalines)arebeing obtained by in situ soil-water salinity sensors. Concurrent continuous recordings of light energy from underwater and aerial sen- sors are also being obtained. ECOLOGY SECTION, Dr. Robert A. Woodmansee, Head Phytoplankton Productivity in St. Louis Bay (Funded by Du Pont): Phytoplankton productivity is a fundamental community process of primary significance to the aquatic food chain. It is sensitive to a variety of unnatural environ- mental perturbations and is affected by a number of natur- ally occurring variables. Phytoplankton productivity is being measured at six locations in St. Louis Bay by both dissolved oxygen and radioactive carbon techniques and is being related to light intensity, temperature, nutrients, chloro- phyll, phytoplankton and grazing pressure. Environmental Baseline Survey of St. Louis Bay: Benthic Study (Funded by Du Pont): Monthly sampling of benthic infauna and epifauna was initiated in December 1977 as part of an overall effort by the Laboratory to conduct an environmental baseline study in St. Louis Bay. Prior to sampling, equipment was purchased and modified as needed. It was also necessary to hire and train two additional techni- cians. Beginning in December, 39 infauna and 14 epifauna samples were collected each month and transported to the Laboratory' for processing. Seasonal and Spatial Changes in the Macrobenthos of Simmons Bayou, Mississippi (Funded by GCRL): A benthic study conducted in Simmons Bayou was concluded during this reporting period. From this study, a paper entitled “First Gulf of Mexico Coast Record o^Manayunkiaspeciosd'' by Walter T. Brehm, was accepted by Northeast Gulf Science for publication. Another paper entitled “Seasonal and Spatial Changes in the Macrobenthos of Simmons Bayou, Mississippi,'’ was prepared for presentation at the October meeting of the Gulf Estuarine Research Society. A Study of the General Plankton and Floating Compo- nents of the Water Column from the Surface to 1 .200 Meters at Two OTEC Sites in the Northern Gulf of Mexico (Funded by Department of Energy, Ocean Thermal Energy Conversion [OTECJ Program, Lawrence Berkeley Laboratory): Bi- monthly cruises aboard the NOAA boat, VIRGINIA KEY, to OTEC sites for the purpose of collecting plankton and general hydrographic data were initiated in June 1978. A sampling program was established to determine the quantity and position within the water column of planktonic species. This project should provide the OTEC Program with some of the necessary biological data for proper design and imple- mentation of an offshore thermal energy conversion plant. ENVIRONMENTAL CHEMISTRY SECTION, Dr. Julia S. Lytle, Head Sediment High Molecular Weight Hydrocarbons in Bay St. Louis (Funded by Du Pont): During the past decade there has been an increasing concern over the possible effects of petroleum hydrocarbons in the marine environ- ment. Because of this concern, a great amount of research on ihe biogeochemisty of these compounds is in progress. National agencies are initiating hydrocarbon baseline studies to be made on areas ol potential oil pollution which would be subjecl to economical and environmental stress. With the building of a large Du Pont plant on the shore of the Bay, hydrocarbon baseline information was essential. Todocument Ihe present levels of hydrocarbons (aliphatic and aromatic) in St. Louis Bay, 13 sampling stations were used in assessing the hydrocarbon levels from the rivers and from known sites of possible hydrocarbon inputs and also correlated with other sediment studies made at these same stations. Sedi- ments were collected during the first month of the study and hydrocarbon analyses made. These same stations will be sampled during September, nine months after the first collection, and again analyzed. Ill ail effort to use hydrocarbon data to detect the pres- ence of petroleum pollution, parameters have been derived from gas chromatographic data that indicate the presence of petroleum hydrocarbons. Thirteen of these parameters were measured in all sediments analyzed. Changes can be detected by measuring the same parametersat any later lime, thereby establishing both qualitatively and quantitatively theaddition of petroleum influx to these sediments. Studies of Chemical Constituents of Primitive Plants (Funded by GCRL): Chemo taxonomic and geochemical studies continued on primitive plants. Similar studies have been completed previously on ferns, mosses, fungi and lichens. The present study has been extended to include lilies, rushes, sedges and grasses. This study has two purpo.ses. One purpose is to investigate the distribution of biosynthetically related compounds, hydrocarbons and fatty acids, to relate them to a series of ancient plants and to determine what chemical changes took place in the evolution of plants. The other purpose is to establish hydrocarbon and fatly acid distribution patterns that can help in identifying natural- source materials and their environments, and distinguishing them from pollutant sources. The Fate of Organic Pollutants in Estuaries and Rivers Emptying into the Mississippi Sound (Funded by GCRL and Du Pont): This study is a cooperative effort with the Analytical Chemistry Section. The organic pollutants are isolated and characterized by the Environmental Chemistry Section, and trace metals and nutrients are examined by the Analytical Chemistry Section. Tlie object of the .study thus far has been to document the hydrocarbon and total organic carbon levels in St. Louis Bay, Biloxi River and Bay, and the Pascagoula River Systems. A Summary Report 193 In view of the evei-expanding development of coastal zones, a continuing pollution assessment study is proposed to deal with the following issues of environmental concern; 1. The present condition of Mississippi Sound and adjacent bays and rivers needs careful documentation. Following this, future monitoring efforts can then be determined. 2. The sources of pollutants should be located and dispersal of these pollutants documented. The mechanism respon- sible for transport and deposition of pollutants in any area of the Sound must be known for various environ- mental conditions. Fate predictions of materials dis- charged into the Sound system may then be possible. 3. The public needs to be made aware of present and future dangers of pollution to water resources of the Slate. Only an informed public can take action to prevent future detriment to the environment and insist upon clean-up procedures. 4. Guidelines for proper development of the coastal zone should be facilitated by a thorough knowledge of impact potential of pollutants at any location in Mississippi Sound. There will be two distinctly related areas of research. Trace metals to include such elements as copper, cadmium, zinc, nickel, manganese, silver, cobalt, lead and iron will be examined in all sample types used in the study. Their known toxic nature, stability and numerous sources warrant attention in any study. Hopefully, the data gained here will also be useful in predicting the fate of radionuclides as well. Among the organic pollutants to be studied will be hydro- carbons that can result from petroleum pollution. Fatty acids and alcohols, not occurring extensively in petroleum, may be used as tracers of natural organics in the Sound as well as providing additional information on the composition of organic constituents of sediments and water. Both water samples (surface and bottom) and surface sediments will be collected routinely at each sample site. Since trace metals and organics both are generally associated with fine-grain materials when in a nondissolved state, sus- pended material will be examined separately from dissolved components and grain-size analysis of sediments conducted. This may provide correlations to clarify sources of deposited pollutants and assess the importance of suspended materials in transporting pollutants. Other studies have indicated the importance of trace metal-organic associations in water and sediments; therefore, this relationship will be examined as closely as possible. Where more appropriate, laboratory conditions will replace natural ones in trying to elucidate the character of this relationship. Accumulation of Petroleum Hydrocarbons in Gams Taken Near Dredging Operations (Funded by U.S. Corps of Engineers, subcontracted from Micro-Methods, Pascagoula, Mississippi); In order to assess the damage of petroleum hydrocarbons on clams, a study was made to determine the extent of accumulation of petroleum hydrocarbons in clams from two areas, one area off the Florida west coast and the other near Puerto Rico. In doing so, clams from “clean waters” defined the background hydrocarbon distributions while clams from dredging areas defined the input due to mobilization of hydrocarbons from the deposited dredge spoil. Sixty-four samples of clam tissue were analyzed for both aliphatic and aromatic hydrocarbons. Total hydrocar- bons in clams were extremely low (less than 1 part per million). Various gas chromatographic parameters were used to help distinguish between biogenic hydrocarbons and those of petroleum origin. It was apparent that clams taken from various locations accumulated different types of hydrocarbon pollutants according to types of pollutants in the dredging muds. Information concerning sediments and their hydrocarbon distributions is essential to the understanding of the uptake and resuspension of hydrocarbons. We were not given access to this information, thus complete interpretation could not be made. FISHERIES MANA CEMENT SECTION, Mr. William J.Demoran,Head Oyster Resource Assessment and Monitoring Segment of the St. Louis Ray Baseline Survey (Funded by Du Pont): The study involves the mapping of existing oyster reefs to determine their present condition as to productivity, natural mortality, spawning and setting, and predators with empha- sis on the incidence of one known disease that affects oysters along the Gulf coast. Historical and recent salinity data are being analyzed ia order to determine what effect they have had and are having on oyster growth in the Bay. An Economic, Environmental, Engineering and Legal Assessment of Oyster Depuration in Mississippi (Funded by M-ASGP): This study deals with the managerial aspects of the oyster resource as they might pertain to harvesting and monitoringofoystersasthey are processed in the depuration plant. FISHERIES RESEARCH AND DEVELOPMENT SECTION, Mr. J. Y. Christmas, Head Fishery Resources Monitoring and Assessment (Funded by NMFS and GCRL): The completion report and manu- script for the original monitoring and assessment project (ciilininaled in September 1 976) were finalized and approved by NMFS. The manuscript includes papers covering the principal species in each fishery. The following were con- sidered for each species; immigration; growth; size distri- bution and abundance collected by various gear types; distribution by habitat, estuarine area, temperature and salinity,, seasonal trends in abundance; prediction of abun- dance; length-weight relationship and condition; and age at maturity. The current monitoring and assessment project is on schedule. Cooperative efforts to provide data leading to achievement of optimum yield from fishery resources are continuing. Appropriate segments of this work have been closely coordinated with NMFS research in Gulf waters. 194 HOWSE Continuing liaison with the Mississippi Marine Conservation Commission (MMCC), M-ASGP. numerous other Slate and Federal agenices and industry representatives has provided fgr a progressively improved scientific base for fishery management. The Mississippi brown shrimp crop for 1 978 was adversely influenced by the occurrence of a high -salinity, low-temper- ature and low-dissolved oxygen waiermass that moved Ihrougli the island passes just before the MMCC opened the Mississippi shrimp season. It was opened in accordance with recommendations based on project data collected for them by GCRL, Catch data were not available but preliminary estimates indicated a good average year for brown shrimp with improved catches expected in July based on the abun- dance of postlarvac on the nursery grounds. Wliile shrimp followed typical patterns of abundance with a good crop predicted for late summer and fall harvest. Postlarvac and early juveniles appearing in estuarine nursery areas and available catch data for pink shrimp indicated increasing harvests from Mississippi waters. Blue crabs were abundant throughout this period and a very large year-class of juveniles were in the sampling area during the 1978 sampling period, indicating that the blue crab population can continue to provide as many hard-shell crabs as processors can handle. However, changes in harvest- ing regulations may adversely affect production from Missis- sippi waters. While total 1977 Gulf menhaden landings were appre- ciably below those of 1976, landings in Mississippi increased 27% from 1976. Fishing effort in the Gulf purse-seine fishery in 1977 was 8% less than in J976. Predictions based on juvenile abundance and a 6% increase in elTort indicated a good season in 1978. Preliminary catch data indicate that predicted harvest volume will be accomplished. As expected from the abundant year-classes reported last year, spotted seatrout and redfish provided excellent fishing in Mississippi waters in 1978. After a decrease in numbers cauglit from the 1976—77 year-class of croakers there was a sharp increase in the 1977—78 year-class moving inshore. Survival of croakers to recruitment in the offshore fishable population continued to be low. Other finfish species followed typical patterns of movement with no evidence of serious problems. Fisheries Planning (Funded by GCRL); Active partici- pation in fishery planning activities of NMFS, Gulf States Marine Fisheries Commission, the Commission’s Technical Coordinating Committee and subcommittees, Gulf Stale- Federal Fisheries Management Board, Sea Grant Association, MMRC, MMCC, Gulf of Mexico Fisheries Management Council and several professional societies provided for effective input of Mississippi’s position in practically all Gulf of Mexico fishery planning activities. Project pei^onnel served as a member of the MMCC. A regional management plan for Gulf menhaden, com- pleted and published by GCRL last year, was implemented by the Gulf Slate-Federal Fisheries Management Board. Laboratory personnel served on the menhaden management committee. SciciUific and statistical committees for plans being developed by the Gulf of Mexico Fisheries Manage- ment Council included several members of the GCRL staff who have acquired expertise in specific fisheries. Development of a Regional Fishery Management Plan for Gulf Shrimp (Funded by NMFS); The Shrimp Fishery of the Gulf of Mexico United States: A Regional Manage- ment Plan was completed and published in August 1977. The 128-page document was developed in a series of 11 workshops. The Gulf Shrimp Management Task Force included specialists from each of the five Gulf states and open-meeting workshops were held in each stale to facilitate fisherman and industry participation in the planning process, A comprehensive summary of this plan (20 pp) was developed and published in November 1977. The plan was implemented by the Gulf State-Federal Fisheries Manage- ment Board early in 1978. Laboratory personnel served on the Board’s Shrimp Management Committee. A Proposed Mississippi Marine Finfish (Selected) Fishery Management Plan (Funded by M-ASGP); This project pro- vides for development of a proposed management plan for selected Mississippi marine finfish in a cooperative effort with the University of Southern Mississippi. A working group comprised of personnel from GCRL, USM, MMCC and Sea Grant Advisory Service, held workshop sessions each month. The MMCC selected ten species for inclusion in the plan and appointed a 12-person Advisory Committee to provide input from recreational and commercial fishermen, processors and consumers. Work is proceeding on schedule. Environmental Baseline Survey of Bay St. Louis, Nektonic Macrofauna (Funded by Du Pont); This segment of the multidisciplinary study of St. Louis Bay provides for collec- tion and study of the nektonic macrofauna in the Bay. Sampling was started in October 1977 and by the end of June 1978, a total of 252 biological samples and 1,080 physico-chemical measurements had been completed. All samples were processed on schedule and verified data were stored in the Laboratory computer files. About 200 species have been identified from biological samples. GEOLOGY SECTION, Dr, Ervin G. Otvos, Head Offshore Barrier Island Study (Funded by GCRL): This is a study of the geologic history, genetic conditions and present state of six Mississippi-Alabama barrier islands. Drilling on western Petit Bois Island was completed in the summer of 1977, Two coreholcs drilled in 1978 on western Dauphin Island completed that island’s subsurface geological exploration. Five coreholes were drilled in a transect between the mainland and Horn Island. The U.S. Coast Guard and the Mississippi National Guard provided periodic photo coverage of certain critical island sections, allowing the monitoring of changes over a short period of time. Processing of previously acquired core material progressed A Summary report 195 in the sedimentation laboratory. Part of the accumulated findings on this island have been organized for a later presentation at a professional meeting as well as for publication. Santa Rosa Island (Funded by GCRL): Study of this island has started with the acquisition of U.S. Corps of Engineers' drill core material from Birmingham, Alabama, and island drill core material from a testing laboratory in Pensacola, Florida. Comparison between this island and the Alabama-Mississippi barrier islands has major signincance in understanding their fnimalionand development conditions. Origins of Lake Pontchartrain and Surrounding Holocene Areas (Funded by GCRL): Collection and organization of available material continued with the view of publishing in the fall of 1978. Holocene Geology of Hancock County Marshland (Funded by GCRL). A paper was prepared in conjunction with the Botany Section, based on available data involving florislio aspects of the study area. Chenier Genesis in the U.S. and Worldwide (Funded by GCRL): A paper has been prepared with the collaboration of Dr. W. A. Price, Corpus Christi, Texas, and accepted for publication in Marine Geology. Beach Sand Analysis (Funded by GCRL): Granulometric analysis was performed on numerous samples for the Physical Oceanography Section. Shoreline Erosion- Mitigation Assessment and Planning for the Mississippi Gulf Coast (Funded by MMRC): This project was performed jointly with the Physical Oceanog- raphy Section. A report on partial results was submitted, but the second stage was not funded. Pleistocene Development in Southeastern Louisiana (Funded by GCRL): Field and laboratory work continued. Special attention was paid to the Bayou Sara area’s (Mississippi-Louisiana) Pleistocene chronological problems. St. Louis Bay (Funded by Du Pout); Monthly sediment analyses of collecled Bay samples were performed on this project. MICROBIOLOGY SECTION. Dr. David W. Cook. Head Evaluation of Methods for Long-Term Freezer Storage of Blue Crabs for Use in Picking Plants (Funded by MMRC): An evaluation was made of two procedures for freezing and storing blue crabs until they could be picked. In one proce- dure, the crabs were given a short cook and then frozen whole with a final cook before picking, In the second process, the crabs were cooked and packed with only the crab cores being frozen, Included in the evaluation were pickability test, lump and total meat yields, bacteriological quality, palalability test, and shelf-life of the picked crab- meal. Meat picked from crabs which had been frozen by both methods was found to be acceptable to a taste panel in terms of flavor, texture, and appearance. Meat yields were comparable between frozen crabs and fresh crabs picked on the same day. The quality of the lump meat appeared to be unaffected by the freezing process. Bacteriological quality of the meal picked from the frozen crabs was good and the keeping quality of the meat was excellent. Viral Evaluation of Prohibited Oyster Growing Waters (Funded by M-ASGP): This joint project with the University of Southern Mississippi is designed to asse.ss the relationship between numbers of pollution-indicator bacteria in the water and the level of viruses found in the oysters. GCRL is responsible for water- and oyster-sample collections and bacteriological analysis. Data produced iii this project will be available to Slate and Federal regulatory agencies for use in assessing present-day water quality standards. Environmental Baseline Survey of Si. Louis Bay: Micro- biological Investigations (Funded by Du Pont): Water sam- ples from 14stationsin the Bay and adjacent rivers are being collected at 2-week intervals and analyzed for coliforms and fecal colifomis. These data will document the present-day levels of sewage pollution in the Bay. Each month water samples collected at 22 stations are analyzed for microbial biomass u.sing adenosine triphosphate (ATP) methodology. These data will be used to correlate with phytoplankton counts and productivity measurements. Populations of selected groups of bacteria are being studied in sediments from seven locations around the Bay. Metabolic activity rates and total biomass are being determined. A Study of the Genus Bacillus in Marine and Estuarine Sediments (Funded by GCRL): The distribution, taxonomy and ecology of the genus Bacillus in the estuarine sediments of St. Louis Bay are being Investigated. The numbers of Bacillus spores found at seven locations in the Bay arc being enumerated monthly and the percentage of pigment forms noted. Thirty isolates are being selected from each of three stations monthly for future taxonomic studies. The Determination of the Acute Toxicity of Dredged Material to Fish and Microinvertebrates under Standard, Static, Bioassay Conditions (Funded by GCRL): Sediment samples collected from the inner harbor and approach channel to the Broadwater Beach Marina in Biloxi. Mississippi, were processed in accordance with U.S. Environmental Protection Agency (EPA) guidelines and tested as toxicants to blue crabs, mysid shrimp, and penaeid shrimp. As slated in last year's report, no deaths were observed with the blue crab, and mysid shrimp mortalities were random and not associated with sediment (toxicant) concentration. During fiscal year 1978, further tests were conducted with brown shrimp. Mortalities were random and not related to sediment concentration. The information generated by these investigations was utilized by the Broadwater Beach Marina in obtaining the pennils required to perform maintenance dredging in their harbor. Persistence and Degradation of Insecticides in Estuarine Water and Sediment (Funded by GCRL): Investigations 196 HOWSE regarding the persistence and degradation of inallhion, parathion, methyl paralhion, diazinon, and mirex in the estuarine environment were curtailed during fiscal year 1978 to allow lime for the other toxicology investigations described elsewhere in this report. Bacterial cultures capable of degrading the organophosphorus insecticides are being maintained for future use. Insecticide Persistence in Natural Seawater as Affected by Salinity, Temperature, and Sterility (Funded by FFA): This investigation was conducted in conjunction with studies underway at the EPA Laboratory at Gulf Breeze, Florida, in an attempt to more clearly delineate the various biological and chemical factors that determine the recalcitrance of insecticides in the natural enviionmeiii. This project was actually completed in fiscal year 1977 with the final report being prepared during fiscal year 1978. MICROSCOPY SECTION, Dr. Harold D. Howse, Head Studies on Lymphovystis Virions (Funded by GCRL); Studies of lymphocystis tumors continued with the collab- oration of the Parasitology Section. Tumors were examined from different species of fishes, several of which were new host species. Diameters of the virions examined in each species were as follows: 387 nm Pomancanthus semicircu- latus, Koran angel fish; 287 nm Zanclus canescens, Moorish idol; 287 nm Chaetodon capsilralus, foureye butterfly fish; 259 nm Platax orftendaris, batfish; and 287 nm Holancan- thus ciliaris, queen angelfish. Further studies are in progress on cellular response to this viral pathogen in different fish species. Histological and Cytological Investigation of Various Organs and Tissues of the Atlantic Croaker Micropogonias undulatus (Funded by GCRL): The first phase of a histo- logical and cytological study was begun on the several organ systems and tissues of the Atlantic croaker. Numerous juvenile fish were processed and sectioned in longitudinal and cross-sectional views for selective staining. Additionally, various selected tissues were excised from sexually mature specimens and prepared for comparison of seasonal changes. The second phase of this project will consist of the preparation of an atlas of normal croaker histology and cytology. The results of this study will provide the basis for determining pathological changes occurring in croakers exposed to various toxicants under experimental conditions. Fine Structure of the Peritrichous Ectocommensal Zoothatnnium sp. (Funded by GCRL): This project, con- ducted in collaboration with T. G. Sarphie and W. E, Hawkins, University of South Alabama, dealt with a proto- zoan that attaches to gills of penaeid shrimp. When present in large numbers, these ectocommcnsals can suffocate com- mercially important shrimp and cause severe economic problems in aquaculture. The results of this study are presented in a paper now in press. OYSTER BIOLOGY SECTION, Dr. Edwin W. Cake, Jr.. Head Oyster Spat Monitoring Program (Funded by GCRL): This study concluded 2 years of oyster “spat” monitoring to determine the time and intensity of setting at five loca- tions in Mississippi Sound and adjacent waters. The study also provided information on the setting time and density of major oyster competitors and foulers, such as barnacles. These data collected to date are being provided to oyster culturists who wish to plant cultch material for collecting seed oysters on private leases, Plankton Sampling for Oyster Larvae (Funded by GCRL): This is the second and final year of a study to monitor the number of oyster larvae in Biloxi Bay plankton as a means of esliniating spawning activity and potential spat settle- ment. The data gathered should assist oyster biologists and the oyster industry in predicting the best time for planting cultch materials. Oyster Growth and Mortality Study (Funded by GCRL): This is also the last of a 2-ycar study to determine the growth and mortality rales of various types of .seed oysters at five locations in Mississippi Sound and adjacent waters. Oysters reared in lagoons on the barrier islands appear to grow faster and survive better than those “planted” at inshore locations. The reproductive processes for all seed- oyster types appear to be normal for the salinity and temper- ature regimes at all five locations. Biological and Ecological Studies of the Oyster Boring Clam (Funded by GCRL): The final year of a 3-year investi- gation was completed on the basic biology and ecology of Diplothyra smithii. Its life cycle has been documented and its burrowing behavior and mechanisms have been observed and documented. Distribution and population dynamic data from Mississippi Sound burrowing clams are being assessed. The reproductive biology including the gonadal, spawning and setting cycles have been documented. Morphological studies of the adult clams have also been completed. Gametogenesfs and Spawning of Mississippi Sound Oysters (Funded by GCRL); During the last year of this 2-year study, monthly and bimonthly gonad samples of oysters from western Mississippi Sound were examined to determine the effects of temperature and salinity on annual spawning cycles. The results of this study should aid in our understanding of the basic reproductive biology of Gulf Coast oysters. Black Drum Predation on Oysters and Other Inverte- brates (Fnndtd by GCRL); This 3-year study was completed during the past fiscal year. It provided the first experi- mental documentation of the predatory behavior and predation rates for this little-known species. Under experi- mental conditions, large drum will consume approximately one oyster per-pound-of-body-weight per day. The black drum is, therefore, perhaps the most destructive oyster predator in Mississippi Sound. A Summary Report 197 Oyster Depuration in Mississippi: Environmental, Legal and Management Assessments (Funded by M-ASGP and GCRL): Tlie first phase of a 3-ycar study was completed during the past year and the final report will be available to the public during fiscal year 1979. Results of the study indicate that there are no insurmountable environmental, legal, or management problems that would preclude the operation of onshore oyster depuration facilities in Missis- sippi and Alabama. The study did identify problem areas, including a lack of Slate regulations that would be required to operate a Stale-approved depuration plant. Draft regula- tions are included in the final report for consideration by the Mississippi Legislature and the U.S. Food and Drug Administration. Oyster Depuration in Mississippi: Engineering ^ssess- ments (Funded by M-ASGP and GCRL): Tlte second phase of a 3-year study was initiated during fiscal year 1978 in cooperation with sanitary engineers from Mississippi State University, During the study, a 2-bushel, pilot depuration facility was constructed and operated at the GCRL Oyster Biology Facility on Pt. Cadet in Biloxi. Preliminary results indicate that oyster waste products (feces and pseudofeces) can be removed continually during the depuration process and treated via presently acceptable sanitary methods. This reduces the need for complete daily wash-downs, which are expensive, and energy- and time-consuming. Off-Bottom Cleansing of Oysters in Mississippi Sound (Funded by GCRL): A 2-year study was initiated during the fiscal year 1978 to compare off-bottom and on-hoi luiii cleansing (relaying) of oysters. New techniques and devices are being utilized in an attempt to reduce loss of relayed oysters during cleansing by holding them in off-bottom, containerized storage. The method holds promise for that segment of the oyster industry which is now relaying oysters to lea.sing bottoms in approved shellfish waters, and which is suffering considerable oyster losses due to burial, pred- ation^ rough handling, etc. This study is expected to benefit the entire oyster industry by increasing harvestable oyster stocks and reducing expenses. Oyster Mariculture (Funded by GCRL): Current experi- mental oyster mariculturc involving one seed oyster hatchery includes, but is noi limited to, the following: out-of-season conditioning and spawning of Mississippi Sound oysters; experimental raceway and tank culture of hatchery-reared seed osyters; engineering design and evaluation of experi- mental hatchery methods; evaluation of new cultch mater- ials for hatchery-reared seed oysters; the effects of various predators (crabs, black drum, spiny boxfish) on seed oysters; and the feasibility of utilizing natural spatfall to increase seed production using Mahes and shell spat collectors. PARASITOLOGY SECTION, Or. Rnhin M. Over sneer, Head Parasites of Commercially Important Fishes (Funded by NMFS and GCRL): The project primarily concerns the use of parasites to indicate migratory and feeding behavior of the Atlantic croaker. Feeding habits of several other local llnfishes arc also being investigated by analyzing .stomach contents. The project additionally covers aspects of the effects of selected parasites on their respective hosl.s. Handbook of Marine Parasites of the Northern Gulf of Mexico (Funded by M-ASGP and the Stale of Mississippi): This project terminated in January 1978, resulting in an illustrated guidebook for students and laymen to help them understand some of the common parasites likely to be encountered in local finfishes and shellfishes. Gulf Coast Survey of Fish and Shellfish for Parasites Pathogenic to the Human Consumer (Funded by the U.S. Food and Drug Administration): The purpose of the proj- ect was to survey four finfishes and four shellfishes season- ally from Mississippi, Texas (Galveston) and Florida (Tampa) for a.scaridnids, heterophyids, and other parasites of public health importance. Representatives of those parasites found were fed to mice and other mammals to determine their ability to live in or cause pathological changes in the hosts. The project terminated 30 June 1978. Pathological Effects of Larval Thynnascaris Nematodes in the Rhesus Monkey (Macaca mulatta) (Funded by the U.S. Air Force): The primaiy purpose of the study was to determine if one of the common larval nematodes {Thynnas- caris Type MB) causes pathological alterations in the alimentary tract of a monkey. Studies on Helminths of the Northern Gulf of Mexico Region (Funded by GCRL): A delenninatlon of parasites in hosts involved in the above projects as well as other hosts are included in this study. This included life histories of the parasites and the relationships between a parasite and its host. PHYSICAL OCEANOGRAPHY SECTION, Mr. Charles K. Eleuterius, Head Wave Refraction Analysis (Funded by M ASGP): Loss of life and erosion of valuable waterfront properly have been attributable to an adverse wave climate in Mississippi Sound and on the seaward side of the barrier islands. Applying a coniputerwavc-rcfraclion model, utilizing linear-wave theory, to a uniform bathymetric grid of the study area generates refraction diagrams. These diagrams, when interpreted, show the locations of high-energy areas and wave caustics under varying wave climates. This information will be useful in marine navigation, especially to the inexperienced boat operator, and to landowners and engineers in employing methods to prevent further erosion of waterfront property. Characterization of Tidal Bayou and Development of Statistical Evaluation /Monitoring Techniques (Funded by GCRL): This is a continuing study of a critical area of estuarine systems, the conlrihutary - especially the tidal bayou. To ascertain the most useful parametric statistics to characterize the system, data have been collected for the past 4 years. In addition to establishing baseline statistics, statistical techniques are being developed for monitoring 198 I-IOWSE the bayous for changes that mighl ordinarily go unnoticed. Ait'-Sea Heat Flux (Funded by GCRL): Water temper- alure is un important factor in the growth and migration of marine species. Attempting to forecast an opening dale for shrimping season based on a slalislical shrimp size is ham- pered by llie variability in growth rate which is dependent, in part, on the water temperature. This study mckides the development of a predictive, stochastic model of heat flux in Mississippi Sound that will provide a means of predicting the thermal structure of the water column when given a set of conditions. Hydrology of St. Louis Bay (Funded hy Du Pont): The objective of this .study is the development of an extensive and intensive baseline of hydrographic parameters to serve as an estimate for ‘"normal” conditions. The field data collection effort, which is coordinated with the other disci- plines participating in the environmental baseline study, obtains measurements of water temperature, salinity, pH, dissolved oxygen, luibidiiy and water color. In addition, fixed and automated sampling platforms continuously record wind speed and direction, water elevations, air temperature, photic period, pH, dissolved oxygen, salinity and water temperature. The continuous records of tides and winds, supplemented by direcl-curretit nieusuiements, will be used to calibrate a mathematical model of water circulation for St, Louis Bay. The product of the Bay study will be a viable mathemat- ical algorithm of circulation, determination of flushing rate, physical characterization, baseline (norm) of some physical property levels, and quantification of some physical processes. PHYSIOLOGY SECTION, Dr. A. Venkatarantiah. Head Fvaulation of the Nutritional Value of Grass from High Marsh Areas to Brown Shrimp Penaeusaztecus Ives (Funded by MMRC): The objectives of this study were to determine the feasibility of utilizing the high marsh grass Spartina patens and shrimp shell waste in shrimp culture as supple- mentary feeding. The food pellets compo.sed of modified grass with a maximum of 4% protein and shrimp shell waste gave a greater increase in biomass than the pellets composed exclusively of grass. Control pellets produced a slightly better growth than the grass pellets. Shrimp pro- vided with loose gias.s and shrimp shell waste showed a tendency toward high cannibalism. The use of mlcrobially modified Spartina patens as a food source does not appear feasible, at least in laboratory shrimp culture. Wilhmorc effective decomposing techniques, high marsh grass may prove useful for the production of detritus in pond culture. Addition of shrimp shell waste to the food appears to improve growth and survival, and warrants further investigation. Acute Effect of the Simulated Du Pont Effluent on the Survival and Behavior of Penaeid Shrimp (Funded by GCRL): Tlie acute effect of simulated Du Pont waste was tested on the mortality rates, behavioral responses of juven- ile brown shrimp Penaeus azrecus, during 96- and 144-liour exposure in 10, 20, 35, and 50% effluent concentrations at 80, 86 and 90'’F. Control shrimp normally survived during the 96-liour period. A few of the unfed, but not the fed, shrimp died in 144 hours at 86 and 90° F. Survival was good in 50% effluent concentrations except that one death occurred at 90°F in 96 hours. Some of the starved shrimp died at 86 and 90°F. A few of the fed animals also died in 10 and 35% effluent concentrations without showing any correlation between the concentration of effluent and mortality. While high temperature by itself is known to be detrimental to their survival, addition of effluents to the medium may augment the adverse effects at high temperature. A Literature Research Project on the Lethal Upper Temperature Limits for Coastal Water Fauna (Funded by GCRL): About 400 new references have been added to the existing 1,200 or so previously collected for the purpose of compiling a reference book. Effect of Simulated Du Pont Effluent on the Physio- logical Responses of Commercial Penaeid Shrimp (Funded by GCRL): Preliminary experiments were done with a Warburg respirometer to determine the effect on the O 2 consumption in brine shrimp infected with the bacteria, Leiicothrix With the existing respirometry techniques no significant differences were found between the normal and bacterially infected brine shrimp. Caloric Densities of some Shellfish Meat Fats (Funded by GCRL): The caloric content of meats of crab, lobster, three species of shrimp, crawfish, oyster and squid was analyzed by oxygen-bomb calorimetry. Whole meat of lobster yielded the lowest Calories and that of squid the highest calories. The percentage of fal content in the meats differed significantly; oyster meal has more fat than the other dtellfish meats analyzed, and crawfish very low fat. Tlie caloiic content of the extracted fat differed dis- tinctly among the species. Fats of squid and lobster .showed very low-caloric energies while fats of oyster, blue crab and pink shrimp showed high-caloric energies. It is suggested that the nature of the lipid classes contributes more toward caloric density of the tissue than the total lipid content. Size-Related Variations in the Tissue Cholesterol Content of the Brown Shrimp Penaeus az/ecus Ives (Funded by GCRL): Muscle (tail) cholesterol increased linearly as body weight increased among female shrimp, whereas males maintained a steady level independent of size. Based on these findings, it is suggested that the bulk of marketable shrimp, 60-68 heads-on count/pound, have relatively lower cholesterol levels than is reported in nutritional and medical literature. Compared to caviar, organ meats, brains and eggs, shrimp muscles showed a low cholesterol content. Effect of Cooking and Frozen Storage on the Choles- terol Content of Selected Shellfish (Funded by GCRL): Cooking decreased the cholesterol content of crabineat but A Summary Report 199 brought about no significant change in shrimp or oystei meat levels. Freezing and thawing of raw tissue increased cholesterol content of oyster and shrimp meats but did not affect the level in crabmeal. Lit>id and Sterol Levels as Indices to Deiermiue the Optimum Harvestable She in Crassosirea virgimea (Gtnelin) (Funded by GCRL): The lipid content of the meat was directly related to size on a logarithmic scale and was inde- pendent of sex. Tire relationship between total sterol con- tent and weight of oysters was nonlinear. Adult males show higher sterol content than females. It is suggested that oysters with an 8 to 10 g meat weight or 95 to 100 mm shell length would be ideal for harvest because oysters in that size range have low sterol and triglyceride levels. SYSTEM A TIC ZOOLOGY SECTION , Mr. C. E. Dawson, Head Systematic Studies on Fishes of the Families Micro- desmidae, Dactyloscopidae and Syngnathidae (Funded by the National Science Foundation); Studies on three families of fishes continued throughout the year. Revisionary studies on the pipefish genets Penetopteryx (and relatives), Hippich- thys and Bhanotia were completed. Revisions Oostethus, Doryichthys and related genera, as well as reviews of the western Atlantic pipefishes (Syngnathidae) and sand star- gazers (Dactyloscopidae), also continued throughout the year. In connection with these problems, studies were con- ducted on fishes at the California Academy of Sciences and National Museum of Natural History. SPECIAL FACILITIES MARINE EDUCATION CENTER, Mr. Gerald C. Corcoran, Curator Visitations to the Marine Education Center increased from 23,844 in fiscal year 1 977 to 39,1 55 in fiscal year 1978. While .some of the increa.se may be attributed to the opening of the new Gulf Marine State Park, the majority must be considered as normal average yearly increase. In cooperation with the M-ASGP, four work.shops in marine science were conducted for inland teachers. These were held in Oxford and Jackson, Mi.ssissippi, and Huntsville and Montgomery, Alabama. Emphasis was placed on the use of inland facilities in conducting classes in marine edu- cation. The primary aim of the workshops was to acquaint teachers with the concept that ‘'marine” is now generally accepted as referring to water in general and not necessarily salt water. Approximately 120 teachers attended the workshops. At the request of a Slidell, Louisiana, parents group, a course in marine science for gifted children was written. The presentation of the cour.se took place in July 1978. Subjects covered were coastal geography, the Gulf of Mexico as a habitat, diversity of marine life, water mammals and identification of selected specimens. Field trips were scheduled to augment and supplement classroom discussion. The ongoing marine science courses for teachers had a total enrollment of 44 students, 26 in the basic course and 18 in the advanced course. As in previous years, enrollment included people in occupations other than teaching. Included were one Navy commander, one chemist, two Air Force retirees, one Veterans Administration Hospital employee and three housewives. A slide program and field trip to Horn Island were con- ducted for a class of teachers from Tougalou College. This was another attempt to intrtKluce marine science to inland teachers. Eight students were involved, and, although the study consisted primarily of saltwater animals, the students were instructed in the general characteristics of plants and animals. Techniques for adapting the information to fresh water were emphasized. The student-intern program was continued with two students from Gulfport and one from Biloxi participating. Sluderils were given credit through their schools for advanced biology. Subjects covered were identification of animals, care and maintenance of captive specimens, and preservation. The .special educational program for Creative Learning in Unusual Environments groups from Memphis, Tennessee, was conducted again this year with a total of six groups taking part. Tlfis program is growing each year. The White- haven Methodist Day School, Memphis, took advantage of the program by bringing a group to the Center for the fourth coriseculive year. The Marine Education Center makes arrangements for these groups to attend Marine Life in Gulfport, tour the Biloxi harbor, and go .seining on the beach at night, in addition to their visit to the Center exhibits. Tw'o Explorer Posts In Environmental Science were formed during the year under the auspices of the Boy Scouts of America program. Programs such as water sampling tech- niques and fish identification were presented. Center person- nel continued to act as merit badge counselors to the Boy Scouts of America on 16 different merit badges. The Explorers were taken on field trips to the local beach for collection of specimens and water samples. Equipment and literature at the Center were utilized to conduct programs for the Scouts. Future plans call for a session on ecology with a possible trip to Horn Island to study a special eco- logical habitat. Three radio programs on marine-related subjects were presented in cooperation with radio station WGCM in Gulf- port, The topics included sharks, poisonous marine animals and local snakes. Two programs, in cooperation with the Public Information Section of the Laboratory, which included aquaria of horseshoe crabs and a film showing, were conducted for local libraries in Pa.scagoula and Moss Point, Mississippi. Consultations continued between the Marine Education CeiilcT and Marine Life, Inc. of Gulfport. The veterinarian responsible for administering to marine mammals at Marine Life has been assisted on several occasions by Center per- sonnel. Local pet shops utilize the services of the Center in dealing with outbreaks of diseases in their aquariums. 200 HOWSE Visitors request, and arc provided, information concerning correct aquarium maintenance procedures, fish diseases and snake handling. Local hospitals routinely send snakes to the Center for positive identification prior to dealing with snake bite cases. One out of two snakes proved to be poisonous during the past year. The Marine Education Center contributes to the publi- cation ot the National Marine Education Association entitled Current and the Curator edits a monthly newsletter, Lfl/era/ Line, published by the North American Native Fish Associ- ation. Mr. Corcoran was selected as “Conservation Educator of the Year” for the State of Mississippi by the Mississippi Wildlife Federation. THE GUNTER LIBRARY, Mr. Malcolm S. Ware, .Senior Librarian A record amount of binding was done this year with long backruns of 39 journal titles being bound. Nineteen monographs were also bound. A number of rare and out-of- print titles were secured, among which were three notable titles: Gurney's British Fresh-Water Copepada (in three volumes); Moore’s Condition and Extent of Natural Oyster Beds ... Mississippi and Alabama, and The Micro tornists (Vade-Mecum). Another important purchase was a backrun of the Discovery Reports on microfiche, purchased from E. P. Group of Companies in England. Backruns of journals were strengthened in 49 titles. Thirty-nine new journals were added, 21 as standing orders. Two new sections were established within the collections; i.e., Environmental Impact Statements, and the Piatt Reprint Collection. Four hundred fifty books were purchased during the year, and donations further strengthened library holdings. Dr. B. H. Atwell of the Earth Resources Laboratory, Slidell, Louisiana, donated runs of journals in ten titles, 36 books and 60 reprinfs. Dr. P. A. Isaacson of the Department of Public Services, Albany, New York, donated 549 scientific papers which included some journal numbers. Dr. R. E. Baglin, .Tr., of National Marine Fisheries Service, Miami, Florida, donated books and reprints numbering collectively 280. Stalfmembcrs making donations to the library included Drs. David W. Cook, Gordon Gunter, Harold D. Howse, Ervin G. Otvos and Mr. John P. Steen, Jr. Five hundred thirty-six reprints were cataloged and shelved , adding to the approximate total of 20,000 processed reprints. (There arc still an additional 5,000 to 8,000 unpro- cessed reprints backlogged.) The book cataloger processed about 500 books (October- June) bringing the cataloged portion oflhe book collection up to about 35% of the total. Incoming interlibrary loans numbered about 196 and more than 70 items were loaned out to other libraries, A year-end survey revealed that the new card catalog and microfilm filing cabinets were 65% filled. The microfiche system was 25% filled in its present mode. Visiting researchers used the Gunter Library in increasing numbers this year, coming from three laboratories at Dauphin Island and the Pascagoula fishery station. Other visiting researchers were from various Mississippi and Ala- bama colleges and universities, as well as from local and regional agencies such as Geo-Marine, Richardson, Texas; National Space Technology Laboratory, Bay St. Louis; Ingalls ShipbuildingDivision of Litton Industries, Pascagoula; and Jackson County Planning Commission, Pascagoula. During the fall and spring, field-trip groups from affiliate schools used the collection on a one- and two-week basis. In addition, a record number of science fair students came to the library from the junior and .senior high schools of the six coastal counties. Also, college-level students enrolled in continuing education courses at the Marine Education Center and on the main campus, used the library every quarter. Throughout the year various researchers, both U.S. and foreign, were hosted on a “walk-in” basis. ICHTHYOLOGY RESEARCH MUSEUM, Mr. C. E. Dawson, Head Four hundred twenty-two lots, representing approxi- mately 5,000 specimens were cataloged. An important collection of fishes by the R/V OREGON off the coasts of Venezuela and Brazil was received from the NMFS. Gifts of specimens, including a number of pipe- fishes, were received from several U.S. and foreign insti- tutions. The Museum now houses one of the world’s most comprehensive collections of pipefishes. Loans of specimens were made to a number of U.S. and foreign institutions. Identifications were provided for fishes sent by investigators in the U.S., Central and South America, Europe, Australia, etc. WA TER ANAL YSIS LABORA TORY, Dr. Thomas F. Lytle, Head The Water Analysis Laboratory has processed samples for the sections of Physical Oceanography, Microbiology, Oyster Biology, Botany, Anadromous Fishes; for the Du Pont project and the Mississippi Air and Water Pollution Control Commission. These analyses have included: ortho- phosphate, total phosphorus, nitrate, nitrite, ammonia, sulfate, silicate, chloride, turbidity, suspended solids, alkalinity and chlorophyll, and phaeophytin. In all, 2,635 analyses have been performed (excluding those for the Du Pont project). Many of the analytical schemes have been modified to comply with Federal guidelines. In addition to actual analyses, staff of the Water Lab have advised other section members and persons outside the Laboratory on mattersof pollution, water-quality criteria, sample collection, etc. Some of the teaching for the biboratory’s courses, Special Problems in 1977 and Special Topics in 1978, was handled by Water Lab personnel. COMPUTER SECTION, Mr. David Boyes, Head Several significant events occurred during the year. Foremost was the use of on-site data retrieval systems for scientific analysis. Production run lime, the actual amount of time the computer is used for analysis, increased to 75% A SUMMARY Report 201 of total run time, the amount of time the computer was in operation. Work on multidimensional statistical analysis and graphical programs departed from the development stage and entered the test-and-application stage. The training program for section personnel has proven to be an effective tool for increasing the performance of the Computer Center. Tasks that could only be performed by one individual can now be undertaken and accomplished (with a small loss in overall efficiency) by another member of the section. The net result is a decrease in computer down-lime. The total number of jobs, programs run on the computer, for the year was about 2,266, which required a total of 1 ,084.69 hours. The following projects (sections) were the main users: Fisheries, 386 jobs; Du Pont project, 386 jobs; Finance, 310 jobs; Graduate program 289 jobs; Oceanog- raphy, 250 jobs; Botany, 98 Jobs; Systematic Zoology, 94 jobs; and Parasitology, 59 jobs. PUBLIC IN FORMA TIONJPUBLICA TIONS SECTION Miss Catharine Cantpbell, Head News releases were sent to 50 selected daily and weekly newspapers, television and radio stations, wire services and special correspondents. In addition, pictures of field-trip groups and summer college students were made and sent to hometown and campus publications. A general article on the Laboratory was furnished the Misaissippi Press Register (Pascagoula) for a special edition printed in March. Assistance was also provided to outside writers, photographers and television crews in obtaining interviews with members of the Laboratory staff. A 4-day open house was planned and held November 9- 12, 1977. The first three days were devoted to junior and senior high school .science students and about 530 students and teachers participated. The final day, Saturday, was for the general public and over 650 visitors attended. Not all interested science classes could attend open house and they requested Laboratory tours at other times, including six college and eight secondary school groups. Through visits to public libraries in the coastal commun- ities, in June 1978 the Section began a new public infor- mation program entitled “What’s in the Gulf for you?” This was planned originally as a summer activity, however, it will be continued as long as interest warrants. Depending on the size and hours of the libraries visited, staff members of the Section and of the Marine Education Center .spend up to 7 hours on a visit. The Marine Education Center also pro- vides an aquarium with a live horseshoe crab for the visits. Color slides explaining the processing of seafood in local plants and a i6-mm sound film “World Beneath the Sea” are shown; Marine Education Leafiets, tide tables, shark recipes, marine career information, and other free materials are distributed. Visitors and library personnel are made more familiar with the programs and activities of the Marine Education Center, the Laboratory, and its publications. From July 1, 1977 until January 8, 1978, the Section produced 19 new 15-minule “On Course” radio programs and 9 rerecorded programs. Programs were broadcast by nine radio stations along the coast and in Meridian and Jackson. In January, after completing 2 full years of broad- casts, the Section began a year's vacation from the radio series. Living Science Comments, a new program, was under- taken at the request of the Director to preserve for future generations the voices and comments of outstanding scientists. Two recordings have been made, the first of Dr. Gordon Gunter of this Laboratory, and the second of Dr. J. Frederick Walker, former professor at the University of Southern Mississippi, now retired. Master tapes will be maintained and duplicated as needed. Color slides and black and white pictures were made of field sampling activities in connection with the environ- mental baseline survey of the Bay of St, Louis, conducted by the Laboratory for Du Pont. A slide program is to be assembled with narration; black and white prints were used in Marine Briefs, GCRL’s monthly newsletter. Additional color slides were made in crab processing plants for the cooperative seafood industry program series and the narra- tion was revised. For the first time class pictures were taken for the summer courses tauglit at the Laboratory. Students and professors were given an opportunity to purchase prints and others will be available in an album in the Gunter Library. The Section staff provided Laboratory participation in the Mississippi Slate University-sponsored Harrison County Fair at Edgewater Mall Shopping City in September 1977; also, in the Mississippi Academy of Sciences annual meeting exhibits in Biloxi during March 1978. Copy was edited and set in page format and illustrations prepared for printing the December 1977 issue of Gulf Research Reports, Volume 6, Number I. Finished copies were received in April and 758 copies were mailed by the staff. The issue contained seven regular papers, six short com- munications and the Director’s summary report of Labora- tory activities. After materials for this issue went to the printer, work began on the next issue, Volume 6, Number 2. Similar publications work was performed by the staff on the Technical Report Series, Number 2 of the series, The Shrimp Fishery of the Gulf of Mexico United States: A Regional Management Plan, was published in August 1977. Technical Report Series, Number 2, Part 2, a condensed form of the management plan, was published in November 1977. Distribution of both was handled primarily by Mr. J. Y. Christmas, Assistant Director of the Laboratory for Fisheries Research and Management, who served as co- editor with Dr. David Elzold of the University of Southern Mississippi. Section personnel wrote and edited copy, took photo- graphs, set copy and made layouts for 1 2 monthly issues of 202 HOWSE Marine Briefs, the Laboratory newsletter. This was the seventh year of publication; about 3800 copies are distri-^ buted regularly. ACADEMIC PROGRAM NEW AFFILIATE One institution became affiliated with the Laboratory during the year for the purpose of training its students in the marine sciences, bringing the total of out-of-state affiliates to 38, This new affiliate is Middle Tennessee State University, Murfreesboro, Tennessee. SUMMER SESSION. Dr. David W. Cook, Registrar The 1977 summer academic session involved 91 students registering individually for a total of 125 student courses. Forty -nine students registered through Mississippi schools, 65 througli oui-of-statc affiliates and 10 through nonaffili- ated out-of-state institutions. Formal courses offered during the 1977 session were; Marine Chemistry, Drs. Julia S. Lytle and Thomas F. Lytle, staff Salt Marsh Ecology, Dr. Lionel N. Eleuterius, staff Physical Marine Geology, Dr. Ervin G. Otvos, staff Chemical Marine Geology, Drs. Ervin G. Otvos, Julia S. Lytle, and Thomas F. Lytle, staff Marine Microbiology, Drs, David W. (’ook and William W. Walker, staff Introduction to Marine Zoology, Dr. Buena S. Ballard, Southwestern Oklahoma State University Marine Vertebrate Zoology and Ichthyology, Dr. J. William Cliburn, University of Southern Mississippi Marine Invertebrate Zoology, Dr. Edwin W. Cake, Jr., staff Marine Fisheries Management, Mr, J. Y. Christmas. staff, and visiting specialists Marine AqiiacuUiiie, Dr. Edwin W. Cake, Jr., staff Marine Ecology, Drs. James T. McBee and Robert A. Woodmansee, staff Marine Botany, Dr. R. B. Channell, Vanderbilt University Special Problems in Marine Science, staff During the 1977—78 academic year, 44 students earned credit in courses in marine science for teachers that were offered through the Marine Education Center located in Biloxi. Courses offered were; Basic Techniques in Marine Science for Teachers, Mr. Gerald C. Corcoran, staff Advanced Studies in Marine Science for Teachers, Mr. Gerald C. Corcoran, staff GRADUA TE RESEARCH PROGRAM Courses offered in the Graduate Research Program during this period in which students participated included; Seminar, Special Problems in Marine Science, Special Topics in Marine Science and Graduate Research in Marine Science. A total of 10 1 .seme.sier hours credit were earned by these students. The Graduate Research Program has seen significant growth during the year with the addition of seven new students. One student completed his degree and four stu- dents have completed their research projects and returned to their parent campu.scs for further coursework. Fourteen students in the program were candidates for the master’s degree and eight candidates for the doctorate. Each candidate’s name, thesis title, degree sought and home university arc listed below according to research sections directing their work; Anadramous Fishes Section: William W. Falls, “Food habits and feeding selectivity of larval striped b'd^s, Morone saxatilis (Walbaum), under intensive culture,” Ph,D., Uni- versity of Southern Mississippi. Analytical Chemistry Section: Leo N. Ricliard, “The presence of aromatic hydrocarbons and bena(a)pyrene in Mississippi Gulf Coast oysters,” M.S., University of Missis- sippi. Botany Section: James C. Garrison, “Some relationships of salt marsh vegetation to abundance of the marsh peri- winkle l.ittorinairrorata Say, *’M.S., University of Mississippi. Stephen H. Sky -Peck, “A study of growth and nitrogen content of Spartina alternijhra and Juncus roemerianus in response to source and concentration of nitrogen,” M.S., University of Mississippi. Ecology Section: Jerry A. McLelland, “The summer vertical distribution of Chaetognatha in the northeastern Gulf of Mexico,” M.S., University of Southern Mississippi. John P. Steen, Jr., “Factors influencing the spatial and temporal distribution of selected crustacean plankton species in Davi.s Bayou,” Ph.D., University of Mississippi. Michael C. Torjusen, “The occurrence of planktonic larval and postlarval fishes in waters of the northern Gulf of Mexico and the Mississippi Sound,” M.S., University of Mississippi. Oyster Biology Section: David H. Barnes, “Polychaetes associated with an artificial reef in the north central Gulf of Mexico,” M.S., University of Southern Mississippi. David A. Blei, “A successional study of the hydrozoans inhabiting an artificial reef in the north central Gulf of Mexico,” M S,, University of Southern Mississippi. Neil Cave, “Predator-prey relationships involving the American oyster, Crassostrea virginica (Gmclin), and the black drum, Pogonias cromis Linnaeus, in the Mississippi Sound,” M.S., Southeastern Louisiana University. Alfred P. Chestnut, “Substrate competition between Crassostrea virginica (Gmclin) and associated sessile marine invertebrates,” Ph.D., University of Southern Mississippi. John D. Demond, “Amphipod fouling of an artificial reef in the north central Gulf of Mexico,” M.S., University of Southern Mississippi. Katherine A. McGraw, “A comparison of the growth and survival rates of hatchery-reared and natural oyster spat at A Summary report 203 selected locations in the Mississippi Sound and adjacent waters with conuneiUs on the biology of oysters in Missis- sippi,” Ph.D., University of Washington. John E. Siipan, “A comparison of ‘oft-bottom’ relaying oysters in the Mississippi Sound,” M.S., University of Southern Mississippi, Parasitology Section: Daniel R. Brooks, “Systematic studies on the digenetic tremalodes of crocoliliaiis with emphasis on the family Acanlhostomidae,” Ph.D., University of Mississippi. Thomas L. Deardorff, “Nematodes of the genus Thynas- caris Dollfus 1933, (Aiiisakidae) in the northern Gulf of Mexico,” Ph.D., University of Mississippi, Alan C. Fusco, The life cycle and development of iSi>ocfl'wa//fl«ussp.,’'M.S., University of Southern Mississippi. Tom E. Maltis, “Larval development of two trypano- rhynch tapeworms from Mississippi Sound,” Ph.D., Univer- sity of Southern Mississippi. Mobashir Ahmad Solangi, “Pathological changes in some estuarine fish exposed to crude oil and its water-soluble fractions,” Ph.D., llnivenshy of Southern Mississippi. Physiology Section: Ann L. Gannam, “Effect of replacing dietary animal protein with plant protein supplemented by methionine on the growth and survival ofPenaeid shrimp,” M.S., University of Southern Mississippi. Shiao Yu Wang, “Studies on the effect of size and temperature on the respiration rates of brown shrimp, Penaeus uztecus Jues, iji declining oxygen tension,” M.S., University of Southern Mississippi. Zubir Bin Din, ”The food and feeding habits of the com- mon bay ancltovy, Anchoa mitchilli diaphara Hildebrand,” M.S., University of Mississippi. SCIENTIFIC FIELD TRIP PROGRAM As an adjunct to the teaching program, each year the Laboratory provides living accommodations, classroom laboratories, and essential services to visiting scientific field trip groups made up of college and university students and their professors. Such groups may stay for periods of up to several weeks, live in the dormitory, use laboratory boats to make collections of marine life from the sea and from the beaches of offshore islands, and study their specimens in the classroom laboratories. During fiscal year 1978, the Laboratory was visited by 36 of these Held trip groups. The total number of people involved were 537 professors and students who stayed an average length of 3.66 days. Some canae as far as 2,000 miles to study the marine life of the Gulf of Mexico. SPECIAL AND COMMUNITY SERVICES FISHER Y ASSISTANCE A mixing chart for solutions made from 65% available chlorine dry compound was drawn up and distributed to seafood plants. A request had been received to establish the mixing ratios necessary to formulate 30-gallon quantities of 50-, 100-, and 200-ppm chlorine solutions for use in seafood plant operations. The charts were printed on water- proof paper. These charts were to take the guesswork out of formulating the three solutions. A file of seafood regulations from the southeastern states was assembled. Frequent lequesls for specific information concerning out-of-slate regulations are received from processors shipping seafood across state lines. Visits to three Virginia seafood processing plants were arranged at the request of a Biloxi seafood packer. The Virginia plants briefly steam their oysters before they reach the shuckers. This causes the shell to open slightly, making it easier to cut out the meat, which increases the percentage of whole oysters to cu i ones. The Biloxi packer was interested in introducing such a process in his plant if the process proved favorable, which it did. Seafood Newsletter (Funded by GCRL): A monthly newsletter designed for seafood management personnel was cstabli.shed under the title The Biloxi Schooner honor- ing sailing vessels used in Mississippi’s early seafood industry. The publication contains articles of pertinent information gathered from trade journals and scientific publications; Federal government publications; and notes taken at sem- inars, conferences, and trade conventions. The contents are technical and designed to be of practical benefit to those in the seafood busine.ss. Sixty copies are currently being printed and mailed to the industry. Reorganized Mississippi Seafood Laws (Funded by GCRL); Mississippi’s seafood laws were rewritten in simpler language for clarity; related regulations were grouped for better organization, and the two sets of laws were combined into a single text. This was done because the seafood industry has long had problems with understanding the regulations as they were originally published. The project’s final draft was reviewed by the Mississippi Stale Board of Health after which copies were printed and mailed to the State’s seafood processors. Product Fact Sheet-Oysters {Funded by GCRL): At the request of the Mississippi Shellfish Packers, Inc., a Product Fact Sheet was written. Processors were having continuous problems with shipments of oysters being mishandled by distributors and retailers. Some type of educational material was needed to inform persons on how to care for oysters after they leave the processing plant. The Product Fact Sheet included information on the nutritional value of oysters, coloration variatons, and how to properly handle and merchandise them in commerce. The Product Fact Sheet was composed in a photo-ready format and given to the president of the Mississippi Seafood Packers, Inc. Copies were to be printed and supplied to members for inclusion in shipments of iced oysters. It is hoped that distributors and retailers will read the sheet as they open the boxes. This information should help improve the shelf life of the product and reduce time and revenue 204 llOWSE lost by the industry in picking up spoiled oysters from retail outlets. Surveys were made on oyster beds at Gollott Oyster Farm to collect oysters for bacteriological studies, to check the salinity of the water over the bed, to count the number of oyster drills (conchs) on it and to establish the percentage of dead oysters resulting from oyster relaying operations. It was the first year (hat the MMCC had issued private oyster leases to individuals or corporations. In these areas of good water quality, polluted oysters may be kept until they cleanse themselves, which takes about 15 days. A trip was organized fur several local seafood processors to attend a workshop for seafood retailers that was held in New Orleans. Afterward, a number of copies of the speaker’s publication. Operations Manual for the Seafood Retailer, were ordered and distributed at their request to processors who could not attend. A seafood processor was assisted in locating a safe, approved food preservative for trial use in packaged oysters. Owners of two seafood retail markets requested and received assistance in evaluating their facilities. A list of suggestions was drawn up that would hopelully lead to an increased sales volume. An oyster processor was assisted with the evaluation and selection of automatic packing equipment to be used in a planned plant expansion. SEAFOOD SANITA I'lON Seafood Sanitation Program (Funded by GCRL); At the request of processors, the Microbiology Section makes plant inspections and collects samples for bacteriological testing to deterinine any problem areas. Suggestions are made for correcting any deficiencies noted in plant sani- tation practices. The program “In-Plant Sanitation-Crab Processing Plants,” developed last year, has been upgraded and pre- sented in several local plants to assist in the education and training of plant personnel. During the fiscal year, 303 crabmeat and 222 oyster samples were collected and analyzed for aerobic plate, coliform and fecal coliform counts. In addition, all crab- meat samples were checked for Escherichia coli. This required over 800 hours of laboratory testing. Personnel traveled over 1,500 miles in collecting samples, visiting plants for evaluation and presenting programs. ENVIRONMENTAL AFFAIRS COMMITTEE This Committee is composed of all the senior scientific staff members at the Laboratory and is coordinated by the Ecology Section. The Committee provides an interdisciplinary approach to environmental problems in the wetlands and estuaries of Mississippi, primarily as a service to the MMRC, which partially funds this work. However, this Committee also cooperates with other Slate and Federal agencies on special projects that are not under the direct jurisdiction of the MMRC. The majority of this work deals with the review of permit reijiiests for work proposed in the wetlands and estuaries. Committee members are asked for their comments and recommendations on each permit request. In most cases a site visit is made by representatives of the Committee. Based upon these inputs, a letter to the MMRC is drafted stating any objections the Committee may have, reasons for these objections and recommendations that may reduce or eliminate the objectives. The Comniitlce reviewed some 110 permit applications throughout the year. In addition, an environmental evalu- ation of an industrial discharge in Mississippi Sound was conducted and benthic samples were taken and processed for U.S. Fish and Wildlife Services personnel evaluating potential spoil areas for modification of the Pascagoula Ship Channel. Several members of this Committee were also involved in meetings with the Mississippi Air and Water Pollution Control Commission in conjunction with the Jackson County 201 Plan. PUBLIC SEMINARS The Gulf Coast Research Laboratory hosts a series of staff seminars throughout the year. These seminars are open to the public and speakers include invited scientist.s as well as officials from various levels of Local, State and Federal Government. The central purpose of the seminars is to pro- mote better dissemination, understanding, and use of scientific information at all levels of society. Seminars presented during fiscal year 1978 were as follows: '"Current Research Efforts at E.P.A. Laboratory, Gulf Breeze, Florida” by Dr. D. R. Nimmo, U.S. Environmental Protection Agency, August 16, 1977. "Water Hyacinth for Waste Water Treatment” by Mr. Bill Wolverton, Senior Research Scientist, National Space Technology Laboratory, September 20, 1977. "Fishery Management in Mississippi-Its Progress and Needs” by Dr. Richard Leard, Director, Mississippi Marine Conservation Commission, October 4, 1977. "Ectoparasites: Life on Man” by Mr. Alan Fusco, Parasitology Section, Gulf Coast Research Laboratory, October 18, 1977. "Jellyfish Toxins: Mechanisms of Action” by Dr. Paul M. Toom, Associate Professor of Chemistry, University of Southern Mississippi, November 8, 1977. "Effects of Slave Trade on Parasite Dispersal” by Mr. Tom Deardorff, Parasitology Section, Gulf Coast Research Labor- atory, November 22, 1977. "Antarctic, Land and Sea-Its Terrestrial and Marine Life” by Dr. Stephen Sliabica, Research Oceanographer, National Park Service, December 6, 1977. "Sharks and Stingrays in the Northern Gulf of Mexico” by Mr. Tom Mattis, Parasitology Section, Gulf Coast Research Laboratory, December 13, 1977. "Bivalve Molluscan Resources and Problems along the U.S. Pacific Coast” by Dr. Ken Chew, Professor, University A Summary Report 205 of Washington College of Fisheries, Seattle, Washington, January 9, 1978. “Field Experimental Studies of Benthic Invertebrates in Florida*' by Dr. David Young, Head Chemical & Biological Branch, Naval Oceanographic Laboratory, January 10, 1978. “Toxic and Suhlethal Effects of Pentaclilorophenol to Crustaceans** by Dr. Ranga Rau, Department of Biology, West Florida State University, January 24, 1978. “Reminiscences on the Development of the Shrimp Fishery and Shrimp Biology on the Gulf Coast of the United States" by Dr. Gordon Gunter, Director Emeritus, Gulf Coast Research Laboratory, February 7, 1978. “Seasonal Changes in Macrobenthic Communities off the Columbia River*' by Dr. Michael Richardson, Naval Oceanographic Research and Development Activity, National Space Technology Laboratory, February 14, 1978. “Developmental Plans for Gulf Islands National Seashore" by Mr. Noel J. Pachta, Assistant Park Superintendent. Gulf Islands National Seashore, February 28, 1978. “Electron Microscopy in Aquatic Pathology" by Dr. William E. Havk^kins, Department of Anatomy, University of South Alabama, March 14, 1978. “Polymers for Energy, Environment and Humanitarian Concerns" by Dr. C. McCormick, Department of Polymer Sciences, University of Southern Mississippi, March 28, 1978. “Oyster Culture in the State of Washington" by Ms. Katherine A. McGraw, Oyster Biology Section, Gulf Coast Research Laboratory, April 4, 1978. “Diversity of Form and Colour in Gulf Coast Amphipod Crustaceans’* by Dr. E. L. Bousfield, National Museum of Natural Science, Ottawa, Canada, April 11, 1978. “Copepods: Both Near and Far** by Mr. John Steen, Ecology Section, Gulf Coast Research Laboratory, April 25, 1978. “Fishery Product Inspection Perspective" hy Mr. Spencer Garrett, Director, National Seafood Quality and Inspection Laboratory, May 9, 1978. "Land Use and Population Patterns’* by Mr. Claude Pittman, Gulf Regional Planning Commission, May 30, 1978. “Successional Changes in Ichthyofauna of a New Artifi- cial Reef** by Mr. Ron Lukens, Anadromous Fishes Section, Gulf Coast Research Laboratory, June 6, 1978. ‘*Coaslul Zone Management Program’* by Mr. J. E. Thomas, Director, Mississippi Marine Resources Council, June 20, 1978. STAFF PUBLICATIONS Brooks, Daniel R. 1977. Evolutionary history of some plagiorchioid trematodes of anumm. Systematic Zoology 26(3):277-289. and Robin M. Overstreet. 1977, Acanthostome digeneans from the American alligator in the southeastern United States. Proceedings of the Biological Society of Washington 90(4) ; 1 0 1 6- 1 029 . , Robin M. Overstreet and Danny B. Pence. 1977. New records of proterodiplostome digeneans from Alliga- tor mississippierisis and Caiman crocodilus fuscus. Pro- ceedings of the Helminthological Society of Washington 44(2):237-238. and Nancy J. Welch. 1977. Marvinmeyeria lucida (Moore, 1954) (Annelida: Himdinea) a commensal of Helisoma trivohis (Say) (Mollusca: Gastropoda) in Nebraska. Transactions of the Nebraska Academy of Sciences 4:21 22. . 1978. Systematic Status of proteocephalid cestodes from reptiles and amphibians in North America with descriptions of three new species. Proceedings of the Helminthological Society of Washington 45( 1 ); I -28. and David Blair. 1978. Description Acantho- stomum quaesitum (NicolL, 191 8)Hughes, Higginbotham, and Clary, 1942 (Digcnea: Cryplogonimidae) in Croco- dylus johnsoni Kreffl from AusiTa\\ 2 i. Proceedings of the Helminthological Society of Washington 45(l):53-56. and James R. Palmieri. 1978. Pronocephalid trematodes from a Malaysian turtle including a new species of Renigonius Mehra, 1939. Proceedings of the Helminthological Society of Washington 45(1 ):34-36. Cake, E. W., Jr. 1977. L.arval cestode parasites of edible moilusks of the northeastern Gulf of Mexico. Gulf Research Reports 6( 1 ); 1 -8. 1977. Experimental infection studies with bolhridio-plerocercoids of Rhinebothrium sp. (Cestoda; Tetraphyllidae) and two intermediate molluscan hosts. Northeast Gulf Science 1(2): 55-59. Christmas, J. Y. and David J. Elzold (Eds.). 1977. The Menhaden Fishery of the Gulf of Mexico United States: A Regional Management Plan. Gulf Coast Research Laboratory Technical Report Series, No, 1 , 53 pp. and David J. Etzold (Eds.). 1977. Ihe Shrimp Fishery of the Gulf of Mexico United States: A Regional Management Plan. Gtilf Coast Research Laboratory Technical Report Series, No, 2, 128 pp. Dawson, C. E. 1977. The pipefish name Syngnathus corru- gatus Weber, a junior synonym of Bhanotia fasciolata (Dumeril). Copeia 1977(4):786-788. 1977. Synopsis of syngnathine pipefishes usually referred to the genws Ichthyocampus Kaup, with descrip- tion of new genera and species. Bulletin of Marine Science 27(4):595~650. 1978. Micrognathus vittatus (Kaup), a junior synonym of M. criniius (Jenyns), with description of the insular pipefish ,A/.fecm5, newsp.Ct^pewl978(l): 13-16. 1978. Review of the Indo-Pacific pipefish genus Hippichthys (Syngnathidae)./^^^"^//!^^^/ the Biological Society of Washington 91(1): 132 157. . 1978, Syngnathus pamcarinatus , a new Austra- lian pipefish, with notes on S. sauvagei (Whitley) and Leptonotus caretta (Klunzinger). Copeia 1978(2): 288 293. 206 HOWSE Eleuterius, Charles K. 1977. Mississippi Sound: The funda- mental period of free oscillaiion. Journal of the Missis- sippi Academy of Sciences 23 ; 1 4 - 1 8. 1978. Location of the Missi.ssippi Sound oyster reefs as related lo salinity of bottom waters during 1973-1975. Gulf Research Reports 6(l):17-23. Eleulerius, Lionel N. 1977. The seagrasses of Mississippi. Journalof the Mississippi Academy of Sciences 22 : 57 -69 . 1977. The seagrasses of Mississippi. Mississippi Game tSi Fish 40(5): 13, Reprinted. and S. P. Meyers. 1977. Alkaloids of Claviceps from SpaTliivd. Mycologia 69(4):838 840. Elzold. David J. and J. Y. Christmas (Eds.). 1977. A Comprehensive Summary of the Shrimp Fishery of the Gulf of Mexico United States: A Regional Management Plan. Gulf Coast Research Laboratory Technical Report Series, No. 2 (Part 2), 20 pp. Foster, Carolyn A. and Harold D. Howse. 1978. A morpho- logical study on gills of the brown shrimp, Penaeus aztecus Ives. Tissue and Cell 1 0( 1 ):77-92. Fusco, Alan C. 1978. Spiro camallanus cricotus (Nematoda: Isoelectric focusing and spectrophotometric characteri- zation of its hemoglobin and that of its piscine host, Micropogonias undulatus. Experimental Parasitology 44(2|:155 160. and Daniel R. Brooks. 1978. A new species of Spirocamallamis Olsen, 1952 (Nematoda; Camallanidae) from Trachycorystes insignis (Steindachner) (Pi.sces: Doradidae) in Colombia. Proceedings of the Helmintho- logical Society of Washington 45(1); 111-114. and Robin M, Overstreet. \^1^. Spirocamallamis cricolus sp. n. and S. halitrophus sp. n. (Nematoda: camallanidea) from fishes in the northern Gulf of Mexico. Ill e Journal of Parasitology 64(2):239-244. Gunter, G. 1977. George Rounsefell-An appreciation. Northeast Gulf Science l(l):2-3. . . 1977- Observations on territoriality in Alli- gator mississippiensis, the American alligator, and other points concerning its habits and conservation. Gulf Research Reports 6( 1 ):79-8 1 . and W. David Burke. 1977. Notes on the status on the gannet {Moms bassanus) in the Gulf of Mexico, with a record from Missi.ssippi. Gulf Research Reports 6(l);83-86. Hendrix, Sherman S. and Robin M, Overstreet. 1977. Marine aspidogastrids (Treniatoda) from fishes in the northern Gulf of Mexico. The Journal of Parasitology 63(5): 810 817. Howse, H. D., A. R. Lawler, W. E. Hawkins, and C. A. Foster. 1977. Ultrastructure of lymphucystis in the heart of the silver perch, Bairdiella chrysura (Lac^p^de), including observations on normal heart structure. Gulf Research Reports 6( 1 ) ; 39 -5 7 . Lakshmi, G. J., A. Venkalaramiah and H. D. Howse. 1978. Effects of salinity and temperature changes on spontan- eous muscle necrosis in Penaeus aztecus Ives. Aquaculture 13:35-43. Lawler, Adrian R.and Robin M, Overstreet. . Absonifi- bula hychowskyi gen, et sp. nov. (Monogenea: Absonifi- bulinae subfam. nov.) from the Atlantic croaker, Mcro- pogon undulatus (L.), from Mississippi, U.S.A. Studies on the Monogeneans. Proceedings of the Institute of Biology and Pedology, Far-East Science Centre, A cademy of Sciences of the USSR. New series 34( I37):83-91 . (In Russian). 1977. DinoBagellaie (y4m>’/owyi>?/m?7)infestation of pompano. In Carl J, Sindcrinann (ed.) Disease Diag- nosis and Control in North American Alarina Aquacul- ture. Developments in Aquaculture and Fisheries Science, Vol. 6. Elsevier Scientific Publishing Company, Amsterdam, pp. 257—264. , 1977. Monogcnetic trematodes of pompano. In Carl J. Sindermann (ed.) Disease Diagnosis and Control in North American Marine Aquaculture. Develop- ments in Aquaculture and Fisheries Science, Vol. 6. Elsevier Scientific Publishing Company, Amsterdam, pp. 265-267. 1977. The parasitic ^moVidgeWdi^Arnyloudinium ocellatum in marine aquaria. Dmm and Croaker 17(2): 17-20. 1977. Notes on sarcophagids from the new host Romalea microptera, and from Terrapene Carolina Carolina. Gulf Research Reports 6( 1 ):69-70. , J. T. Ogle, and C. Donnes. 1977. Dascyllus spp.: New hosts for iymphocystis, and a list of recent hosts. Journal of Wildlife Diseases 1 3(3):307-3 12. , 1978. A partial checklist of actual and potential parasites of some South Carolina estuarine and marine fauna. In Richard G. Zingmark (ed.) An Annotated Checklist of the Biota of the Coastal Zone of South Carolina. University of South Carolina Press, Columbia, pp. 309 - 337. and R. Neil Cave. 1978. Deaths of aquarium-held fishes caused by monogenetic trematodes. l.Aspinatrium poguniue (MacCallum, 1913) on Pogonias cromis (Lin- naeus). Dmm and Croaker 1 8( I ):3 1 -33 . and Steven L. Shepard. 1978. A partially albino blue crab. Dmm and Croaker 18(1):34— 36. Lukens, R. 1977. Notes on Stenopus scutellatus and S. hispidus (Decopoda, Stenopodidae) from Mississippi. Gulf Research Reports 6(1 ):75— 76. Mauldin, Joe K., Nely M. Rich and David W. Cook. 1978. Amino acid synthesis from ''^C-acetate by normally and abnormally faunated termites. Cnptntermes formosanus. Insect Biochemistry 8:105-109. Mcllwain, T. D. 1978. An analysis of salt water angling in Biloxi Bay — 1972—1974. Ph.D. Di.ssertation. University of Southern Mississippi, Hattiesburg, Mississippi. 156 pp. Ogle, John, Sammy M. Ray and W. J. Wardle. 1977. A sum- mary of oystermaricultu re utilizing an offshore petroleum A Summary report 207 platform in the Gulf of Mexico. Proceedings of the Eighth Annual Meeting of the World Mariculture Society 8:447-455. , Sammy M. Ray and W. J. Wardle. 1977. The effect of depth on survival and growth of oysters in sus- pension culture from a petroleum platform off the Texas coast. Gulf Research Reports 6(1 ):3 1-37. Otvos, E. G. 1978. Comments on the “Tunica Hills, La- Miss.; Late glacial locality for spruce and deciduous forest species” by P. A. and H. R. Delcourt. Quaternary Research 9(2):250-252. Overstreet, Robin M. \^)11 . Poecilancistrium caiyophyllum and other trypanorhynch cestode plerocercoids from the musculature of Cynoscion nebulosus and other sciaenid fishes in the Gulf of Mexico. The Journal of Parasitology 63(5):780-789. 1977. A revision of Saturnius Manter, 1969 (Hemmridae:Runocotylinae) with descriptions of two new species from the striped mullet. Universidad National B Mexico. Instituto de Biologia Publications Especiales 4:273-284. 1977. Microsporidosis of the blue crab. In Carl J. Sindermann (ed.) Disease Diagnosis and Control in North American Marine Aquaculture. Developments in Aquaculture and Fisheries Science, Vol. 6. Elsevier Sci- entific Publishing Company, Amsterdam, pp. 1 17-121. and Harold D. Howse. 1977. Some parasites and diseases of estuarine fishes in polluted habitats of Missis- sippi. In IL F. Kraybill, C. J. Dawe, J. C. Harshbarger and R. G. Tardiff ( eds.) Aquatic Pollutants arid Biologic Effects with Emphasis on Neoplasia. Annals of the New York Academy of Sciences 298‘.427-462. and Mary Hanson Pritchard. 1977. Two new zoogonid Digcnea from deep-sea fishes in the Gulf of Panama. Vie Journal of Parasitology 63(5):840-844. — and Thomas Van Devender. 1978. Implication of an environmentally-induced hamartoma in commercial shrimps. Journal of Invertebrate Pathology 31(2); 234-238. Solangi, Mobashir A. and John T. Ogle. 1977. A selected bibliography on the mass artificial propagation of rotifers with emphasis on the biology and culture of Brachionus plicatilis. Gulf Research Reports 6(l):59-68. Wharton, J. IL, R. D. Ellender, B. L. Middlebrooks, P. K. Stocks, A. R, Lawler and H. D. Howse, 1977. Fish cell culture: Characteristics of a cell line from the silver '(icxch. Bairdiella chrysura. In Vitro 13(6):389-397. ABSTRACTS Eleuterius, Charles K. 1978. Classification of Mississippi Sound as to estuary type by vertical salinity structure. Journal of the Mississippi Academy of Sciences 23(Sup.):9l. Eleuterius, Lionel N. 1978. Population variation in the salt marsh rush, J uncus roemerianus. Journal of the Missis- sippi Academy of Sciences 23(Sup .);6. 1978. Observations on the red alga, Caloglossa leprieurii, in salt marshes. Journal of the Mississippi Academy of Sciences 23(Sup.):7. Foster, Carolyn A, and T.G. Sarphie, 1978. Ectocommensal re-latitmship of the pcritrichous ciVinte Zoo thamnium sp. to Penaeid shrimp: electron microscopic observations. Journal of the Mississippi Academy of Sciences 23(Sup.):lll. Fusco, Alan C. 1977. Hemoglobins of the nematode .Sp/ro- camallanus sp. and its piscine host, Micro pagan undulatus. Program and Abstracts of the American Society of Parasitologists 52nd Annual Meeting, 14- 19 August 1977, p. 63. Higgins, George G. and Charles K. Eleuterius. 1978. Missis- sippi Sound: volume, surface area and bathymetric statistics. Journal of the Mississippi Academy of Sciences 23(Sup.);27. Hossler, F. E., J. R. Ruby and T. D. Mcllwain. 1978. Surface morphology of Ihe gill filaments of the mullet, Mugil cephalus. Proceedings of the 7th Annual Texas Society of Electron Microscopy -Louisiana Society of Electron Microscopy Symposium 7( r):40. Loiton, S. R. and D. W. Cook. 1978. Evaluation of the 48- hour IMViC plate procedure for identification of Escherichia coli from seafoods. Journal of the Mississippi Academy of Sciences 23(Sup.);77. Lukens. Ron. 1978. Notes on Stenopus scutellatus and S. hhpidus (Decapoda, Stenopodidae) from Mississippi. Jounml of the Mississippi Academy of Sciences 23(Sup.);113. McGraw, Katherine A. 1977. Oyster growth and survival study in Mississippi Sound. University of Washington (Seattle), College of Fisheries, 1977 Research in Fisher- ies, Contribution No. 470:75. Ogle, John T. 1978. Predator prey relationship between blue crabs and cullchlcss oyster seed. Journal of the Mississippi Academy of Sciences 23(Sup.): 112. Otvos, E. G. and Wade Howat. 1978. Surface and near- surface Pleistocene littoral-marine deposits, Mississippi coast. Journal of the Mississippi Academy of Sciences 23(Sup.):28. Overstreet, Robin M. 1977. Infections of the trypanorhynch cestode Poecilancistrium caryophyllum in flesh of a marine fish. Program and Abstracts of the American Society of Parasitologists 52nd Annual Meeting, 14-19 August 1977, p. 52. Snazelle, Theodore E. and David W. Cook. 1978. Carbohy- drate inhibition of pigment formation in a pigmented, asporogenous mutant of Bacillus cereus. Journal of the Tennessee Academy of Sciences 53(2):61 . Slapp, Dermis S. 1978. A method of thermal structure prediction for estuaries. Journal of the Mississippi Academy of Sciences 23(Sup.):90. 208 HOWSE REPORTS Cake, E. W., Jr. 1978. A pilot seed oyster hatchery for the Mississippi Sound. Final Report. Mississippi Marine Resources Council, Christmas, J. Y. 1978. Shrimp resource management, Missis- sippi. Completion Report: Fisheries assessment and monitoring, Mississippi. National Marine Fisheries Service Project PL 88 -309 -2-215-R, pp. 275-294. 1978. A proposed marine finfish (selected) fish- ery management plan. Quarterly Report. Mississippi- Alabama Sea Grant Cmisortium Project No. R/CP 1. Cook, David W. and James T. McBce. 1977. An evaluation of proposed wastewater discharges into Biloxi Bay. Air and Water Pollution Control Commission, State of Mississippi. Duda, Kay H. 1978. Finfish: Nontarget species. Completion Report: Fisheries assessment and monitoring, Mississippi. National Marine Fisheries Service Project PL 88 309 2-215-4, pp. 208 -215. Eleuterius, Charles K. 1978. Shoreline erosion/miligation assessment and planning for the Mississippi Gulf coast. Mississippi Marine Resources Council, Howse. Harold D. 1977. Activities of the Gulf Coast Resemch Laboratory during fiscal year 1976 77: A summary report. Gulf Research Reports. 6( 1 ):87 106. Loman, Myron J, 1978. Other finfish. Completion Report: Fi.sheric.s assessment and monitoring, Mississippi, National Marine Fisheries Service Project PL 88-309 2-2 1 5- R, pp. 120-167. Lytle, Julia S. and Thomas F. Lytle. 1978. High molecular weight hydrocarbons in sixty-four clam samples from dredging sites in Florida and Puerto Rico. Micro-Methods of Pascagoula, Mississippi. Mcllwain, T. D. 1977. Bait fish rearing. Report in form of a handbook. Mississippi Marine Resources Council. 1977. Quarterly Report; A proposed Mississippi marine finfish (selected) fishery management plan. Mississippi-AJabama Sea Grant Program. Overstreet, Robin M. 1978. Annual Report: Parasites of commercially important fishes. National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Commercial Fisheries Research and Development Act (PL 88-309) Project No. 2-262-R. Perry, Harriet M. 1978, Squid. Completion Report: Fisheries assessment and monitoring, Mississippi. National Marine Fisheries Service Project PL 88 — 309 2-215-4, pp. 313-322. and David L. Boyes. 1978. Menhaden and other coastal pelagic fish. Completion Report: Fisheries asse.ss- ment and monitoring, Mississippi. National Marine Fish- eries Service Project PL 88-309 2-21 5-4, pp. 169-206. and J. R. Herring. 1978. The blue crab fishery. Complelion Report: Fisheries assessment and monitoring, Mississippi. National Marine Fisheries Service Project PL 88-309 2-2 1 5 R, pp. 296-3 1 1 . Van Devender, Tom M. 1978. The shrimp fishery. Completion Report: Fisheries assessment and monitoring, Mississippi. National Marine Fisheries Service Prqjecl PL 88-309 2 215-R,pp. 217-273. Venkalaramiah, A., David W, Cook, Patricia Biesiot and G. J. Lakshmi. 1977. Evaluation of the nutritional value of grass from high mar.sh areas for brown shi imp, Feme us aztecus Ives. Mississippi Marine Resources Council Report, Prqjecl No. CO-76 015. Walker, W. W. 1978. Insecticide persistence in natural sea- water as affected by salinity, temperature, and sterility. U.S. Environmental Protection Agency Ecological Research Series. EPA 600/3-78-044. , A. R. Lawler and W. D. Burke. 1977. Comple- lion Report: The determination of the acute toxicity of dredged material to crabs and shrimp under standard, static, bioassay conditions, Broadwater Beach Marina, Biloxi, Mississippi. Warren, James R., Harriet M. Perry and David L. Boyes. 1978. Industrial bottomfish. Completion Report: Fisheries assessment and monitoring, Mississippi. National Marine Fisheries Service Project PL 88 309 2-215 R, pp. 25-1 18. Gulf Research Reports Volume 6 | Issue 2 January 1978 Effects of 1973 Floodwaters on Plankton Populations in Louisiana and Mississippi Suzanne R. Hawes U.S. Army Corps of Engineers Harriet M. Perry Gulf Coast Research Laboratory DOI: 10.18785/grr.0602.01 Follow this and additional works at: http:/ / aquila.usm.edu/ gcr Part of the Marine Biology Commons Recommended Citation Hawes, S. R. and H. M. Perry. 1978. Effects of 1973 Floodwaters on Plankton Populations in Louisiana and Mississippi. Gulf Research Reports 6 (2): 109-124. Retrieved from http://aquila.usm.edu/gcr/vol6/iss2/ 1 This Article is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf and Caribbean Research by an authorized editor ofThe Aquila Digital Community. For more information, please contact Joshua.Cromwell^usm.edu. Gulf Research Reports, Vol. 6, No. 2, 109 124, 1978 EFFECTS OF 1973 FLOOD WATERS ON PLANKTON POPULATIONS IN LOUISIANA AND MISSISSIPPI SUZANNE R. HAWES AND HARRIET M. PERRY Environmental Quality, U.S. Army Corps of Engineers, New Orleans, Louisiana 70160, and Fisheries Research and Development Section, Gulf Coast Research Laboratory', Ocean Springs, Mississippi 39564 ABSTRACT Studies to assess the impact of floodwarer diversion on plankton populations in coastal waters of Mississippi and Louisiana were conducted from 23 April 1973 through 1 3 July 1973, Fixed stations in l.ake Pontchartrain, Lake Borgne and western Mississippi Sound were sampled once in April, twice in May and June, and once in July. Stations in Terrebonne Parish, Louisiana were visited once in May, June and July. Data are presented on changes in the species composition of zooplankton subsequent to the opening of the Bonnet Carre and Morganza floodways. The hydrographic conditions at the time of sampling are discussed. INTRODUCTION The Bonnet Carre and Morganza floodways serve to divert tloodwaters from the Mississippi River to the Gulf of Mexico (Figure I). The Bonnet Carre Flood way, located 25 miles above New Orleans, empties floodwaters into Lake Pontchartrain. The Morganza Floodway, 280 miles above Head of Passes on the Mississippi River and operating in con- junction with the Atchafalaya Basin Floodway, carries floodwaters to the Gulf by way of the lower Atchafalaya River and Wax Lake Outlet. Severe flooding in the lower Mississippi River valley and prolonged periods of local rain- fall necessitated the operation of the floodways in the spring of 1973. Opening of the Bonnet Carre Flood way began on 8 April with all gates open by 1 1 April. The floodway remained fully open until 30 May with all gates closed by 1 1 June. Opening of the Morganza Floodway occurred on 17 April with vary- ing numbers of bays open until 15 June when all bays were closed. Studies to assess the impact of floodwater diversion on plankton populations were begun subsequent to the opening of the two floodways. Data in this report include plankton samples collected from 23 April 1973 through 13.Tuly 1973. MATERIALS AND METHODS Field Procedure Daytime samples of surface plankton were taken from 23 April 1973 to 13 July 1973 at stations 1 through 16 (Figure 2). These stations were visited once in April, twice in May and June , and once in July. Stations 17 through 23 in Terrebonne Parish were visited once in May, June and July (Figure 3). A plankton net with a mouth opening of 12 inches and mesh aperature of 193 microns was pulled at Manuscript received May 11, 1978; accepted June 7, 1978. a constant speed for an interval of 10 minutes. The samples were preserved in the field in a 5% solution of formalin. Salinity and temperature of the surface water were measured when each sample was collected. Determinations of lernperalLire and salinity were made with a Becknien salinometer (Model RS5-3). Laboratory Procedure The volume of plankton (in ml) for each sample was determined by allowing the sample to settle in a graduated cylinder. Samples with settled volumes exceeding 5 ml were aliquoted with a Folsom plankton splitter. Samples with large numbers of the ctenophore Mnemiopsis mccradyi, or samples containing excessive debris, were examined in their entirety. AREA DESCRIPTION Areas affected by the diversion of floodwaters througli the Bonnet Carre Floodway included Lakes Pontchartrain and Borgne and the western sector of Mississippi Sound. The eastern end of Lake Borgne and the western sector of Mississippi Sound were also influenced by runoff from the Pearl River system, Floodwaters from the Morganza Flood- way affected portions of Terrebonne Parish. Eighteen collect- ing sites were established in the Bonnet Carre outlet area and seven in Terrebonne Parish. Station locations are shown in Figures 2 and 3. To facilitate discussion of data, stations were grouped by geographic location into five areas (Table 1). Discussion of hydrographic and biological data will be by these areas. AREA I Two stations were located in area I in eastern Lake Pontchartrain (Figure 2, Table 1). Bottom types along the south shore of the lake from the Rigolets to Irisli Bayou are predominantly clayey silt (Barrett 1976). Vegetation surrounding this part of the lake is brackish marsh comprised mainly of wiregrass {Spartina 109 no Hawes and Perry Effects of 1973 Floodwaters on plankton 111 Figure 3. Location of stations 17 through 23 in Terrebonne Parish, Louisiana. TABLE 1. Station locations. Area I stations 1 and 2 in eastern Lake Ponlcliartrain Area 11 stations 2 A, 2B, 4, 5 and 6 in western Lake Borgne Area HI stations 3, 7, 8, 9, 10 and 16 in eastern Lake Borgne and extreme western sector of Mississippi Sound Area IV stations 11, 12, 13, 14 and 15 in western Mississippi Sound Area V stations 17, 18, 19, 20, 21, 22 and 23 in Terrebonne Parish patens). Saltgrass {Distichlis spicata), oystergrass (Spartina alterniflora), coco (Scirpus robustus), black rush (Juncus roemerianus) and hogcane (Spartina cynosuroicles) are also present (Chabreck 1972). Submerged vegetation is abundant near Irish Bayou, with tapegrass (Fiz/tomd americana) and widgeungrass (Ruppia maritifna) both occurring. Tapegrass also exists along the north shore of the Rigolets. Water depths average 6 to 8 feet; near the entrance to the Rigolets the depth is 45 feet. Hydrographic Data Salinity. The hydrology of Lake Pontchartrain is greatly influenced by wind speed, wind direction and runoff of the rivers in the Pontchartrain basin; tidal fluctuations play a lesser role (Tarver and Savoie 1976). Darnell (1962) gives an average salinity of S.O ppt for the lake with fluctuations from 3.0 to 8.0 ppt as normal. He notes extremes of 1.2 and 18.6 ppt following heavy rainfalls and tropical Gulf storms, respectively. The studies of Stern et al. (1968), Barret et al. (1971a) and Tarver and Dugas (1973) support DarnelPs data. Surface salinities for stations in area 1 from April through July 1973 are shown in Table 2. During and subsequent to the opening of the floodway, salinities dropped from 1.3 ppt to below 1.0 ppt for the sampling period. Tarver and Savoie (1976) also found salin- ities in the lake dropped during the 1973 opening of the floodway, decreasing from 1.5 ppt in April to 0.3 ppt in June, and rising in July to 7.4 ppt. Salinities following the flood of 1973 were below average during the spring and summer of 1974, 1975 and 1976 (Tarver and Savoie 1976; U.S. Army Corps of Engineers 1974-1976). 112 I-lAWES AND Perry TABLE 2. Hydrographic data and i>ettled volume of plankton for stations in area 1. Station Parameter April ‘May ^May ‘ June ^June July 1 ppt 1.3 0.0 0.2 0.3 0.2 0.0 2 ppt 0.3 0.0 0.0 0.0 0.2 0.3 1 22.1 23.5 26.5 29.1 29.2 30.7 2 “c 22.0 22.2 24.9 27.2 29.6 30.0 1 ml *1.0 *1.0 *1.0 1.0 30.0 *1.0 2 ml *1.0 2.0 *1.0 *1.0 40.0 *1.0 ♦less than Temperature. Surface temperatures in area I from April through July 1973 are shown in Table 2. Temperatures during this period were within the normal range for area 1 as reported by Tarver and Dugas (1973) and Tarver and Savoie (1976). Biological Data Settled Volume. The settled volume of plankton by station in area I is shown in Table 2. Eight of the twelve samples were under 1. 0 ml in settled volume. The high settled volumes in the second June samples included copepods^ dadocerans and large quantities of debris. Zooplankton. A systematic list of zooplankton collected in area 1 is presented in Table 3. Published data on plankton in Lake Pontchartrain include: Wilson 1958; Suttkus et al. 1953-55; Darnell 1958, 1959, 1961, 1962; Bowman 1965; Stern et al. 1968; Stern and Stern 1969; Tarver and Dugas 1973 and Tarver and Savoie 1976. Species diversity and abundance in our samples were low through May, increased greatly in June, and returned to low levels in July. Estuarine endemic species in area I included the copepods Acartia tonsa, Euryternora affinis, Eurytemora hinmdoides, Halicy clops fosteri and the mero- planktonic larvae of benthic invertebrates. Adventitious freshwater plankton occurred in the first May samples and in both June samples. Rhithropanopeus harrisii zoeae were frequently occur- ring organisms, dominating the April and May samples. Zoeae of this species have not been reported from Lake Pontchartrain, although Darnell (1959) noted lai-vae that “may have been” R. harrisii, abundant and widespread in the lake during April and May at low salinities. Darnell (1959, 1961, 1962) reported large endemic populations of R. harrisii adults in the lake, and Cali (1972) found adults of this species common in the City Park pond system in New Orleans, Stern et al. (1968), Stern and Stern (1969) and Tarver and Dugas (1973) all reported decapod zoeae and/or larvae from the lake from May through July. Tarver and Savoie (1976) reported decapod larvae to be the primary component of plankton samples from their two stations in area I. The present study is the first report of Uca sp. larvae in the lake, although Darnell (1959) reported adult Uca sp. Copepods were rare until June when species diversity and abundance increased dramatically. When copepods occurred in numbers, the species composition was unusual, the near absence of A. tonsa being most notable. All previous investi- gators reported A. tonsa to be the primary component of the plankton of the lake. During June 1973, copepods char- acteristic of fresh water iBiaptomus, Cyclops and Meso- cyclops) were common to abundant. This is the first report of these three genera in Lake Pontchartrain. Estuarine endemic copepods occurring in the present study, L’. affinis, E. hirundoides and H. fosteri, have been previously reported from the lake by Suttkus et al. (1953-55), Wilson (1958), Tarver and Dugas (1973) and Tarver and Savoie (1976). Freshwater dadocerans, particularly species of Diaphano- soma, Moina and Bosmina, dominated the plankton during the second June samples. They were present in small num- bers at the time of the first June samples, Suttkus et al. (1953—55), Stern et al. (1968) and Stern and Stern (1969) recorded limited numbers of Bosmina longirostris. Small numbers of estuarine-marine dadocerans, Evadne sp., Podnn sp. and Penilia avirostris, were found by Tarver and Dugas (1973). In addition, Tarver and Dugas (1973) and Tarver and Savoie (1976) reported unidentified dadocerans from the lake. In the latter study, 99% of the unidentified dadocerans were taken in Lake Maurepas and at the mouth of the Tchefuncte River at salinities of 0.0 to 1.4 ppt. The present study is the first report of large numbers of fresh- water dadocerans in eastern Lake Pontchartrain. These populations apparently represent washout from freshwater areas via the Mississippi and Pearl rivers. Large rivers such as the Mississippi normally have limited planktonic populations (Dotson 1966) but during high water, washout from quieter waters dramatically augments these populations. Bryan et al. (1974) reported dadocerans to be the most abundant zoo- plankters in the lower Atchafalaya basin. Cyclopoid cope- pods were the second most abundant organisms in their study. The freshwater dadocerans and copepod.s found in the present study are the same species as found by the above authors to be characteristic of freshwater areas in coastal Louisiana. The meso-oligohaline amphipods Gammarus mucronatiis and Corophium louisianum and the euryhaline species Monoculoids edwardsii were present in April. An unident- ified species of Corophium occurred in June. Tarver and Dugas (1973) reported G. mucronatus and Corophium sp. from the lake, A limited number of isopods were noted during the present study. Edolea sp. has been reported by Effects of 1973 Floodwaters on Plankton 113 Table 3. Systematic list of zooplankton, area I. Species Stage April *May ^May ’ June ^June July Pelecypoda Modiolus JUV* 3 demissus 4 Polychaeta LAR 4 Ostracoda 1 1 1 Calanoida COP 3,008 Calanoida A cartm 768 tonsa 1 25 64 19 Eurytemora hirundoides 128 Eurytemora affinis 2 2 18 64 Diaptomus sp. 5 96 5,888 Cyclopoida COP 192 Cyclop Old a 800 Mesocyclops sp. Halicyclops 20 32 fosteri 5 Cyclops sp. 50 96 Ergasilus sp. 60 Argulus sp. 1 6 64 2 Cirripedia NAU 1 1 Ainphipoda Gammarus 1 1 mucronatus 1 Corophium louisianum 2 Corophium sp. Monoculoides 5 edwardsii 1 Cassidinidea lunifrons Edotea sp. 2 1 Mysidacea ZOE 32 Caridea Rhithropanopeus ZOE 8 2 73 2 harrisii ZOE 280 864 42 670 17 Uca sp. Callinectes ZOE 12 1 sapidus JUV 1 5 8 1 Diaphanosoma brachyurum 49 264,544 Daphnia sp. Simocephalus 2 3 ve lulus 2 15 Simocephalus exspinosus Moina sp. 2 171,520 Moina micrura 160 224 Bosmina coregoni 17,536 TABLE 3 — Continued Species Stage April ‘May ^May ‘ June ^June July Bosmina longirostris Sida 1 384 cry St a Hina 64 Moinodaphnia macleayii 10 Insecta Anisoptera P Tendipes sp. P Osteichthyes LAR 42 5 12 167 68 Syngnathus sp. Naf'as JUV guadalupensis P Lemna ceae P Lemna sp. Spirodeb P P P P oligorhiza Spirodeb sp. Wolffia P P P P columbbna P P P P P Wolffielb floridana P P P * Abbreviations for stages of development in Tables 3, 5, 7, 9 and 1 1 are as follows: COP Copepodid MED Medusa EGG Eggs MEG Megalopa HYD Hy droid NAU Nauplius IMM Immature NYM Nymph JUV Juvenile OPH Ophiopluteus LAR Larva PRO Protozoea LEP Leptocephalus PST Postlarva MAS Mastigopus ZOE Zoea **The letter “P” indicates occurrence in the sample without counts to show relative abundance. Tarver and Dugas (1973) while this paper is the first pub- lished report of Cassidinidea lunifrons in Lake Pontchartrain. Summary Area L Previous studies of eastern Lake Pont- chartrain suggest a planktonic community dominated by estuarine species with the meroplankton composed of the larval stages of R. hamsii and the holoplankton dominated by A. toma. The other major components were adventitious oligohaline and marine forms. Plankton samples in April and May 1973 were characteristically estuarine species dom- inated by the larvae olR. harrisii. In late June this commun- ity was replaced by freshwater-oligohaline species, primarily cladocerans and copepods. From May through June the presence of floating vascular plants such as duckweed (Lemna sp.) and watermeal {Wolffia columbiana) indicated the continuance of riverine washout. 114 Hawes and Perry AREA II Four stations were located along the shores of Lake Borgne from Alligator Point to the mouth of Bayou St. Malo (Figure 2, Table 1). Stations 2A and 2B were added to the study in June. Bottom sediments in the center of Lake Borgne are pri- marily clayey silt, with silty clay present in some areas along the shore (Barrett et al. 1971b). The marshes adjacent to Lake Borgne are brackish and dominated by wiregrass {Spartina patens); some saitgrass (Distichlis spicata) is also present (Chabreck 1972). Water depths in the lake range up to 9 feet (Barrett et al. 1971a). Hydrographic Data Salinity. Salinities in Lake Borgne at the time of construc- tion of the Mississippi River-Gulf Outlet canal ranged from 1.5 to 6.0 ppt (elSayed et al. 1961). After completion of the Gulf Outlet in 1968, salinities in Lake Borgne were substan- tially higher (personal communication, Johnny Tarver, Loui- siana Wildlife and Fisheries Commission). With few excep- tion.s, Tarver found the minimum salinity values for eastern Lake Borgne for April and May 1969—1972 exceeded the maximum value recorded by el Sayed et al. (1961). In April of 1 970, Tarver recorded a high salinity of 1 7.7 ppt. Surface salinities for stations in area II from April through July 1973 are shown in Table 4. With the exception of station 6 in April and station 5 in June, salinities were below 3.0 ppt until July. Stations 2A, 2B and 5 showed a rise in salinity as more saline conditions returned. Salinities at station 6 were highest in April. The geographic location and influence of the Mississippi River— Gulf Outlet canal may account for this. Postflood data from Bayou Bienvenue and Alligator Point, supplied by personnel of the Louisiana Wildlife and Fisheries Commission, indicated that in a normal year, salinities increase during the period April througli July. April salinities in 1974-75 ranged from 1.0 to 5.8 ppt while July salinities ranged from 4.4 to 1 7.0 ppt. Surface temperatures for stalion.s in area II from April through July 1973 are shown in Table 4. The lowest reading occurred in early May at station 5 and the highest occurred during the second June sampling at stations 4 and 6. In general, temperatures were within the ranges recorded by el Sayed et al. (1961) and the Louisiana Wildlife and Fish- eries Commission. Biological Data Settled Volume. The settled volume of plankton by station in area II is .shown in Table 4. No sample was received frarn station 2A for the first June sampling. Of the 23 samples collected, 19 had settled volumes under 1.0 ml. Zooplankton. A systematic list of zooplankton collected in area II is found in Table 5. Papers describing the zoo- Table 4. Hydrographic data and settled volume of plankton for stations in area II. Area Parameter April ^ May ^May ^ June ^June July 2A ppt 0.2 0.2 2.6 2B ppt 0.4 1.9 9.8 4 ppt 0.9 0.5 0.2 1.7 0.6 0.7 5 ppt 0.9 0.3 0.4 0.5 3.2 10.0 6 ppt 4.5 1.3 1.6 1.7 2.7 2.3 2A "c 27.8 29.9 30.0 2B °c 28.9 30.6 30.8 4 "c 24.3 25.1 26.1 29.1 32.6 32.9 5 24.0 23.4 25.8 28,6 30.0 30.8 6 "c 24.4 23.8 27.2 29.4 32.6 32.2 2A ml *1.0 *1.0 2B ml *1.0 *1.0 *1.0 4 ml *1.0 *1.0 *1.0 7.0 3.0 1.0 5 ml *1.0 *1.0 *1.0 *1.0 *1.0 *1.0 6 ml *1.0 *1.0 *1.0 *1.0 7.0 *1.0 *lcss than plankton of eastern Lake Borgne include el Sayed et al. (1961) and Cuzon du Rest (1963), who sampled during the construction of tlie Gulf Outlet canal and Gillespie (1971) who sampled after its completion. Both el Sayed et al. (1961) and Cuzon du Rest (1963) found Acartia form to be dominant in Lake Borgne. Eurytemora hirundoides was the second most common plankter. Cyclopoid copepods and cladocerans were also characteristic of these low-salinity (less than 3.0 ppt) waters. Decapod zoeae were reported, but in exceedingly low numbers (adult Rhithropanopeus harrisii were present). Gillespie (1971) found a typically estuarine plankton com- munity with A. tansa the principal species. The seasonal intrusion of marine species such as Oncaea mediterranea and Undinula vulgaris was noted. Freshwater organisms were conspicuously absent from her sarnple.s. During the opening of the floodway in 1973, the plank- ton population of area U was composed of estuarine and freshwater species. Zoeae of R. harrisii were present in large numbers at each station. Limited numbers of Vea sp. and Sesarma sp. larvae were present from May through July. A few amphipods Acartia tonsa dominated the holo- plankton, with large numbers of this estuarine species present in April, June and July. The freshwater component was dominated by ten species of cladocerans. Five of the six cla- doceran genera found in the present study were reported by Chien(1969)inastudy of the cladocerans of the Pearl River system. Some freshwater cyclopoids, such 2 t%Diaptomussp. and Cyclops sp., were present mainly in June. Insects and/or floating plants were present at each sampling, indicating the continuing washout from fresh water. Representatives of the freshwater group Conchostraca were found during the Effects of 1973 Floqdwaters on Plankton 115 Table 5. TABLE 5 — Continued Systeinalic list of zooplankton, area 11. Species Stage April ‘May ^May ‘june ^June July Species Stage April ‘May ^May ‘june ^June July Coelenterata 20 Ctenophora Beroe sp. Pelecypoda LAR* 10 Tagelus divisus 1 Tellina sp. 1 Brachidonles recurvus 1 Gastropoda LAR 1 3 Polychaeta 1 1 Polychaeta LAR 1 Nereis sp. 1 2 Arachnida 1 Hydiacarina 6 Ostracuda 2 27 Copepod a NAU 3 Calanoida NAU 515 Calanoida COP 12 69 Acartia tonsa 742 3 10 .185 312,813 Eurytemora affinis 1 1 8 Diaptomus sp. 1 5 103 Cyclops vernalis 10 Cyclops sp. 1 20 Ergasilus sp. 3,458 Argulus sp. 1 5 14 22 Cirripedia NAU 1 15 101 Melita nitida 1 Gammunis rnucronatus 1 Corophium louisianum 1 16 Corophium lacustre 1 Corophium sp. 1 Cera pus sp. 3 3 Aegathoa oculata 2 Mysidacea ZOE 3 Caridea ZOE 58 61 19 38 10 Callinectes sapidus JUV 8 4 Rhithropanopeus harrisii ZOE 3,329 844 636 4,232 877 R. harrisii MEG Uca sp. ZOE 1 49 56 Sesarma sp. ZOE 1 75 Conchostraca 9 Diaphanosoma hrachyurum 2 145 3,151 Daphnia sp. 2 1 Moina micrura 1 2 901 Moina affinis 3 Moina macrocopa 2 Moina brachiata Mo inodaphnin macleayii Simocephalus no 1 vetulus 24 Bosmina coregoni 187 Bosmina longirostris 142 Insecta p** Hemiptera JUV P Corixidae NYM p Trichocorixa P Hydropsyche LAR Osteichthyes EGG 5 Osteiebthyes Anchoa LAR 60 5 19 1,088 25 24 mi t chilli JUV 13 1 Anchoa mitchilli Syngnathus 1 SCO vein 2 Syngnathus sp. Myrophis JUV 1 punctatus 1 Atherinidae 107 Gobiidae Hyporhamphus 14 unifasciatus Spirodela sp. 1 P Lemna sp. Wolffia P Columbiana P P P Wolffiella floridana P P Coscinodiscus sp. P P P *See Table 3 **See Table 3 second June sampling. Summary of Area 11. Both el Sayed et al. (1961) and Cuzon du Rest (1963), sampling during the construction of the Gulf Outlet canal, identified A. . ioma as the most abun- dant zooplankler, with freshwater copepods and cladocerans present. Cuzon du Rest (1963) found the plankton of eastern Lake Borgnc characlcrized by fresh or brackish organisms. Gillespie (1971), sampling after completion of the Gulf Outlet, found the plankton of eastern Lake Borgne to con sist almost entirely of the copepod A. tonsa; but the fresh- water organisms found in the earlier studies were noliceably absent. She found plankton in the area to be primarily estuarine with the occasional intrusion of marine species. Plankton samples taken during the opening of the floodway 116 Hawes and Perry in 1973 more closely resembled those taken prior to com- pletion of the Gulf Outlet with A. tonsa abundant and freshwater copepods and cladocerans common. AREA III Six stations were located in area HI, one station near the mouth of Lake Borgne and five stations in the extreme western sector of Mississippi Sound (Figure 2, Table 1), No sample was taken from station 16 in Lake Borgne in April. Bottom sediments in this area are primarily clayey silt or sandy silt. Submerged vegetation is sparse. Emergent vegeta- tion in eastern Lake Borgne includes oystergrass (Spartina alterniflord), saltgrass (Disfichlis spicata)^ black rush (Juncus roemerianus), and wiregrass {Spartina patens). Juncus roemerianus^and Spartina altemiflora dominsil& the marshes of the Mississippi coastline and are the predominant marsh type on Grand Island. Water depths are shallow and range from 2 to 10 feet with depths of 38 feet in Grand Island Pass. Hydrographic Data Salinity. Preflood surface salinities in area III from Three Mile Pass and Blind Bay, Louisiana, for the months of April through July 1968 ranged from 9.9 to 15.5 ppt and 7.5 to 14.3 ppt, respectively (Barrett et al. 1971a). Barrett et al. (1971a) note that salinities in this area are relatively low as a direct result of freshwater drainage from Lake Pontchartrain and Pearl River, and that salinities tend to correlate inversely with discharges from Pearl River. Hydro- graphic data collected in western Mississippi Sound near Point St. Joseph and Grand Island in 1968 record surface salinities ranging from 3.3 to 19.0 ppt from April through July. Christmas and Eleuterius (1973) consider this region of Mississippi Sound as part of the Pearl River estuarine system. They found a yearly mean surface salinity of 12.2 ppt in 1968. They also noted that salinities in this area were considerably lower than those in other Mississippi estuarine systems (liough seasonal trends were similar. Surface salinities for stations in area III from April through July 1973 are shown in Table 6. At the time of the April sampling, surface salinities in area III ranged from 0,0 to 4.2 ppt, the higliest readings taken at stations 7 and 8 near Grand Island. With the exceptions of the first May sample and second June sample at station 16, when salinities were 1.2 ppt, surface salinities at stations in this area did not rise above 0.5 ppt from May through June. Salinities at all stations rose in July with high values of 6.8 and 8.4 ppt recorded at stations 8 and 10, respectively. Isohalines (5.0 ppt increments) drawn for area III in the year following the 1973 flood were generously provided to the authors by Mr. Johnny Tarver of the Louisiana Wildlife and Fisheries Commission. All stations were within the 5.0 ppt isohaline in April and May. In June the 5.0 ppt TABLE 6. Hydrographic data and settled volume of plankton for stations in area III. Station Parameter April *May ^May * June ^June July 3 ppt 0.1 0.0 0.3 0.1 0.2 0.3 7 ppt 4.2 0.3 0.2 0.2 0.2 1.2 8 ppt 4.2 0.4 0.2 0.3 0.5 6.8 9 ppt 0.0 0.0 0.0 0.1 0.2 3.3 10 ppt 0.1 0.0 0.1 0.2 0.2 8.4 16 ppt 1.2 0.0 0.3 1.2 1.8 3 23.7 21.9 24,7 27.7 29.9 32.0 7 23.2 23.1 25.3 29.5 29,8 29.9 8 "c 23.8 24.7 26.1 29,1 30.8 30.3 9 "c 23.6 22.8 29.5 29.9 30.8 29.7 10 "c 23.5 25.4 27.2 29.9 32.0 30.3 16 "c 24.5 26,0 29.1 31.2 30.5 3 ml *1.0 *1.0 *1.0 *1.0 *1.0 *1.0 7 ml *1.0 *1.0 *1.0 *1.0 *1.0 *1.0 8 ml *1.0 1.0 *1.0 *1.0 4.0 *1.0 9 ml *1.0 *1.0 *1.0 2.0 1.0 *1.0 10 ml 1.0 *1.0 *1.0 4.0 *1,0 *1.0 16 ml 9.0 *1.0 *1.0 2.0 *1.0 *less than isohaline shifted northward to include only stations 3, 9 and 10, with stations 7, 8 and 16 falling in the 10.0 ppt isohaline. By July, with the exception of station 16, all stations were again within the 5.0 ppt isohaltne. Temperature. Surface temperatures for stations in area III from April through July 1973 are shown in Table 6. Temperatures between stations showed the greatest monthly variations in May with differences of 3. 5 and 4.8"’C for the two sampling periods, respectively. The lowest read- ing was taken during the first May sampling effort at station 3 (21.9°C), with the highest readings (32.0'’C) observed at station 10 in late June and station 3 in July. Biological Data Settled Volume. Settled volume of plankton by station in area HI is shown in Table 6. Settled volume of plankton was less than 1 .0 ml in 27 of the 35 samples. The highest settled volume (9.0 ml) occurred at station 16 during the first May sampling and was associ- ated w'ith numerous larval fish and large numbers of the zoeal stage of the crab Rhithropanopeus harrmi. Zooplankton. A systematic list of zooplankton collected in area III is found in Table 7. The authors were unable to find published data on the seasonal distribution and abun- dance of zooplankton in the eastern Lake Borgne— western Mississippi Sound area. Butler (1952), during and sub- sequent to the opening of the Bonnet Carre Floodway in 1950, made collections with a fine mesh net (No. 20) and Effects of 1973 floodwaters on Plankton 17 TABLE 7. Systematic list of zooplankton, area III. Species Stage April ^ May ^ May ’ June ^June July Coelenterata HYD* 3 Peiecypoda LAR 3 1 8 3 Modiolus sp. Brachidontes 3 recurvus 3 Gastropoda LAR 1 77 98 Polychaeta Polychaeta LAR 12 Nereis sp. Oligochaeta Hirudinea Arachnida 6 • 3 Hydracarina 3 2 4 15 . 2 Ostracoda 1 10 144 2 Copepoda COP 3 88 Calanoida 17 Acartia tonsa F.urytemora 24 5 17 32 15,882 214 affinis Eury femora 3 37 24 hirundoides 1 25 Eury femora sp. Osphranticum 83 labronecfum 2 Diapfomus sp. 2 2 1 32 135 Cyclopoida Cyclops 3 4 3 18 48 vernalis 2 1 Cyclops sp. Macrocyclops 10 2 16 albidus Euierpma acutifrons ErgasHus sp. 14 486 1 Argulus sp. 4 5 14 83 15 Cirripedia NAU 3 2 Cirripedia Balanus IMM 3 26 improvisus 3 Melita nitida Gammarus ' mucronafus 1 Coraphium louisianum Hyalella 1 1 1 aiieca 1 Isopoda Edofea sp. 4 3 Caridea Pclaemonetes ZOE 273 23 20 35 41 12 pugio 1 Palaemonefes vulgaris 2 Penaeus aztecus Penaeus JUV 3 setiferus JUV 4 TABLE 7 — Continued Species Stage AprU ^May ^May ^June ^June July Cailianassa sp. ZOE 19 JO Callinecres sapidus JUV 2 18 20 Rh ithropanopeus harrisii ZOE 1,235 1,161 291 1,559 343 ■''■■44i' Rh ithropanopeus harrisii MEG 2 8 ' Uca sp. ZOE 10 1 198 262 Sesarma sp. ZOE 2 34 26 4 Leydigia quadrangularis 3 Holopedium amazonicum 2 2 57 14 Diaphanosonw hrachyurutn 3 1 16 579 630 Sida crystallina 24 18 1 Daphnia sp. 43 10 6 3 3 Ceriodaphnia megalops 93 1 1 Ceriodaphnia reticulata 9 1 2 6 Moina micrura 5 37 Moina affinis 7 1 1 1 6 Moina macrocopa 7 1 Simocepholus vetulus 7 42 5 80 1 Simocephalus serrulatus 2 Simocephalus exspinosus 2 31 3 3 1 Bosmina sp. 1 Bosmina coregoni 169 Bosmina longirostris 1 15 Eurycercus lamella tus 26 7 2 4 Chydorus sphaericus 1 llyocryptus spinifer 5 49 Bosminopsis deitersi 14 Moinodaphnia tnacleayii 51 9 Insecta 1 40 Hemiptera JUV 1 1 1 1 Corixidae 1 Corixidae NYM 7 Coleoptera 2 Coleoptera LAR 1 1 Berosus sp. LAR 1 Dytiscidae 1 1 Ephemeroptera LAR 2 Diptera LAR 1 Tendipedidae LAR 4 2 118 HAWES AND Perry TABLE 7 - Continued Species Stage April ^May ^May * June ^June July Osteichthyes EGG 2 Osteichthyes EAR 30 106 10 575 29 40 Bothidae Anchoa EAR 1 mit chilli JUV 20 6 Micropogon undulatus JUV 4 Membras martinica 1 Syngnathus scovelli 1 Coscinodiscus sp. Spirogyra sp. Najas P p** P P P guadalupensis Spirodela P polyrhiza P P Lemna sp. Wolffta P P Columbiana Wolffia P P P P P P floridana P P P P P *See Table 3 **See Table 3 enumerated the phytoplankton species collected over a five-month period. Zooplankters were not identified below the family level. Estuarine-endemic species in area III plankton included the copepods Eurytemora affinis, Eurytemora hirundoides and Acartia tonsa and the meroplanktonic larvae of benthic invertebrates. Plankton characteristic of fresliwater lakes, ponds and rivers occurred in all months. Twenty-one species of cladocerans and several cyclopoid and diaptomid copepods were collected. Zoeae of the xanthid crab R. harrisii dominated samples from April through the first June collections. These zoeae are seasonally abundant in the bays and bayous draining into Mississippi Sound and have been collected in fresh water in Simmons Bayou, Mississippi (personal communication, John Steen, Gulf Coast Research Laboratory). Adults of this species are common on the oyster reefs in Mississippi Sound. With the exception of the euryhaline A. tonsa, copepods identified from area III were oligohalinc or limnetic species. Representatives of the gtnns Eurytemora were present from May througli June. Limnetic copepods were found in all months but were more numerous prior to the July samples. Species of Diaptomus and unidentified cyclopoids were the most abundant limnetic copepods. Small numbers of Osphranticum labronectum, Cyclops vernalis, and Macro- cy clops albidus were taken. Acartia tonsa were abundant only in the second June samples. This species is adaptable to a wide range of temperature and salinity, and the near absence of this species through the first June samples suggests that the continuing flow of fresh water prevented the establishment of a population. Its importance in north- ern Gulf estuaries has been noted by Grice (1956), Cuzon du Rest (1963), Hopkins (1966), Gillespie (1971), and Perry and Christmas (1973). Freshwater cladocerans were collected from April through June with species diversity greatest at the time of the first June samples. Diaphannsoma hrachyurum, Simocephalus vetulus and Bosmina coregoni occurred in largest numbers. Amphipods in area III samples were meso-oligohaline species (Corophium louisianum, Mdita nitida, Gammarus wwcrowflrws) with the exception of the freshwater-oligohaline Hyallela azteca. Summary Area ///. By combining a knowledge of the distribution of benthic adult invertebrates with preflood and postflood salinity data, the authors suggest that the endemic meroplankton in this area would, in all probability, largely be composed of the larval stages of brachyuran crabs and the zoeal larvae of caridean shrimp. Acartia tonsa would probably dominate the holoplankton. Assuming the above to be representative of the spring— summer plankton in area III, the changes in species composition brought about by the 1973 flood waters are evident. Excluding the mero- planktonic larvae and juveniles of benthic invertebrates and juvenile fish, plankton collected in area III was characteristic of a freshwater-oligohaline fauna. The presence of insect larvae, mites, freshwater algae and vascular plants over the sampling period further demonstrates the influence of floodwaters. AREAIV Five stations were located in area IV in western Mississippi Sound in the St. Louis Bay estuarine system (Figure 2, Table 1). Shoreline marshes are dominated by Juncus roemerianus. Beaches in the vicinity of station 1 2 are manmade and main- tained for public use. Beds of shoalgrass Halodule beaudetti existed in the area of station 1 1 in 1968 but have since dis- appeared (personal communication, Lionel Eleuterius, Gulf Coast Research Laboratory). Bottom sediments are primarily muddy to fine sands. Extensive oyster reefs are located in this portion of Mississippi Sound. Hydrographic Data Salinity. Data for preflood and postflood salinities in area IV were furnished to the authors by personnel of the Fisheries Research and Development Section of the Gulf Coast Research Laboratory, Ocean Springs, Mississippi. Mean surface salinities for selected stations in the western sector of Mississippi Sound for the year 1 968 were 1 1 .8 ppt in April, increasing to 20.5 ppt in July. Effects of 1973 Floodwaters on Plankton 119 Surface salinities for stations In area IV from April through July 1973 are shown in Table 8. Salinities were low at all stations in April and during the first May sampling period. Surface salinities at station 1 1 were below 1.0 ppt through June increasing to 14,2 ppt in July. Station 12 showed a gradual increase in salinity through July. Open water stations (13, 14 and 15), more closely adjacent to Gulf influence, exhibited greater fluctu- ations in salinity. Salinities at these stations generally were greater than salinities at shore stations through June. Salin- ities at all stations rose in July. TABLE 8. Hydrographic data and settled volume of plankton for stations in area IV. Station Parameter April * May ^May * June ^June July 11 ppt 0.1 0.2 0.1 0.4 0.3 14.2 12 ppt 0.1 0.0 1.3 1.6 8.6 19.2 13 ppt 0.5 0.0 16.6 5.7 10.6 16.8 14 ppt 1.2 0.0 19.5 6.3 12.3 16,7 15 ppt 2.2 0.7 12.1 6.3 18.6 21.5 11 25.2 26.7 27.1 29.4 31.6 31.2 12 °C 25.1 25.8 25.9 28.5 29.6 30.9 13 °c 24.2 24.4 26.4 28.3 29.0 29.8 14 25.4 24.0 26.5 28.7 28.9 29.8 15 25.2 24.1 25.7 29.0 28.1 29.7 11 ml *1.0 *1,0 *1.0 50.0 *1.0 120.0 12 ml *1.0 *1.0 *1.0 1.0 *1.0 15.0 13 ml *1.0 *1.0 *1.0 2.0 1.0 48.0 14 ml *1.0 *1.0 *1.0 2.0 14.0 1.0 ' 15 ml *1.0 28.0 *1.0 *1.0 42.0 21.0 *less than Postflood data for stations 12 and 15 were available for the years 1974, 1975 and 1976. Salinities in the vicinity of station 12 exhibited similar trends for the three years; low readings in April and May increasing through June and July. Postflood salinity means in 1974 in this area were similar to 1973 means and were slightly higher in 1975 and 1976. Readings for station 15, however, were consistently higher in postflood years. The western end of Mississippi Sound is heavily influ- enced by drainage from the Pearl River and St. Louis Bay estuarine systems and depressed surface salinities are a natural occurrence for short periods of time. Circulation patterns in Mississippi Sound have recently been described by Eleuterius (1976). He noted that during periods of high river discharge the outflow from Pearl River passed through Grand Island Pass and turned southeast with some deflection to the northeast. Outflow from Jourdan and Wolf rivers empties into St. Louis Bay and follows the western shoreline of the Sound for some distance. These two systems operate to depress sniitiity levels in the western Sound during periods of peak river discharge. Temperature. Surface temperatures for stations in area IV from April through July 1973 are shown in Table 8. Temperatures between stations showed the greatest monthly variation (3 .5*^0) at the time of the second June samples. The lowest reading was taken at station 14 (24.0®C) in early May. The highest readings were 3l.6°C and 31.2'^C taken at station 11 in late June and July, respectively. Biological Data Settled Volume. Settled volume of zooplankton by station in area IV is shown in Table 8. Settled volumes were less than 1.0 ml in 17 of the 30 samples, Higli settled volumes associated with the capture of large numbers of the cnidarian Liriope tetraphylla occurred in July at stations 11 and 13. Crustacean larvae and copepods contributed heavily to the settled volume of plankton at stations 11 and 15 in early and late June, respectively. The settled volume of 21.0 ml in July at station 15 was composed primarily of L. tetraphylla and calanoid copepods. Zooplankton. A systematic list of zooplankton collected in area IV is found in Table 9. Little published information exists on the composition of zooplankton communities in western Mississippi Sound. Perry (1975) seasonally moni- tored the occurrence of Callinectes, sp. zoeae and megalopae at stations near the mouth of St. Louis Bay and the western tip of Cat Island. Burke (1975) sampled several stations in the western Sound during an investigation of the occurrence and seasonality of planktonic cnidarians in Mississippi waters. Personnel of the Fisheres Research and Development Section, Gulf Coast Research Laboratory, collected monthly plankton samples in Cat Island Pass from October 1973 through September 1976, removing larval fish and larvae and postlarvae of penaeid shrimp and portunid crabs for ideidificalion. The composition of zooplankton at stations in area IV in April and May 1973 consisted primarily of freshwater- oligohaline species and the larvae of benthic estuarine invertebrates. Estuarine-endemic holoplankters were Acartia tonsa and Eurytemora affinis. The meroplankton was com- posed of the zoeal stages of xanthid and ocypodid crabs, caridean shrimp and unidentified decapods. Callinectes sp. megalopae and a postlarval stage of Penaeus aztecus were found at station 15. Barnacle nauplii were present in small numbers. Freshwater copepods and cladocerans were present in both months with species diversity and numbers greatest during the April sampling period. Identified copepods included Osphranticurn labronectum and Macrocyclops alhidus. Twelve species of cladocerans were recorded, the most abundant being Ceriodaphnia megalops. 120 Hawes and Perry TABLE 9. Systematic list of zooplankton, area IV. Species Stage April ‘May ^May * June ^June July Liriope tetraphylla Bougainviliia MED* 8596 carolinensis MED 85 Eucheilota sp. Rhopalonema MED 8 funerarium Phialidium MED 8 languidum Eirene MED 36 pyramidalis MED 6 Eutima variabilis MED 8 Siphonophora 2 Beroeovata Mnemiopsis mccradyi P P Pelecypoda EAR 2 896 Gastropoda EAR 1 2 560 10 Polychacta 4 2 Polychaeta EAR 272 2 Hydracarina 1 1 1 Ostracoda 130 363 Copepoda NAU 200 1,632 8 Copepoda COP 8,029 Acartia tonsa 2 190 58 1,550 215,084 199 Eurytemora affinis 2 4 Eucatanus pileatus Osphranticum 96 25 labroncctum 1 Diaptomus sp, Labidocera 2 2 aestiva 349 12,256 453 Centropages furcatus Paracalanus 640 10 parvus 1,280 Cyclopoida Oithona 2 1 64 24 brevicornis 1,112 Macrocyclops albidus Corycaeus 3 americanus 224 Corycaeus amazonicus 160 Ergasilus sp. Eutcrpina 20 1 acutifrons 8 2,960 Argulus sp. 1 1 4 5 1 Cirripedia NAU 2 20 8,288 9 Ainphipoda 1 Table 9 — Continued Species Stage April *May ^May ’ June ^June July Cerapus sp. Edoteo montosa 1 4 Aegathoa oculata Muna rcynoldsi 2 ! 4 Decapoda ZOE 6,544 Caridea ZOE 8 8 92 62 133 19 Penaeus aztecus PST 1 1 4 Acetes carotinae PRO 9 Acetes carolinae MAS 2 Callianassa sp. ZOE 64 Upogebia affinis Callineetes ZOE 16 96 12 sapidus JUV 4 1 Callineetes sp. ZOE 23 Callineetes sp. Rhithropanopeus MEG 5 1 5 harrisii Rh ith ropanopeus ZOE 209 134 143 1,313 69 26 harrisii MEG 1 1 2 Uca sp. ZOE 1 833 242 37 Uca sp. MEG 1 Sesarma sp. Panopeus ZOE 31 1 40 herbstii ZOE 16 Panopeus herbstii Panopeus MEG 1 occidentalis ZOE 4 Menippe mercenaria ZOE 4 Holopedium amazonicum 2 4 2 Diaphanosoma brachyurum 1 1,581 118 Sida crystallina 6 1 Daphnia sp. Ceriodaphnia 35 4 3 2 megalops Ceriodaphnia 51 reticulata 5 1 Ceriodaphnia sp. Moina micrura 1 20 6 Moina affmls Moina inacrocopa Simocephalus 2 12 vetulus 2 1 Simocephalus serrulatus 1 Simocephalus exspinosus Bosmina coregoni 18 > 2 Bosmina longirostrfs 1 Eurycercus lamellatus 1 effects of 1973 FLOODWATERS ON PLANKTON 121 TABLE 9 — Continued Species Stage April ^May ^May ^ June ^June July flyocryptus spinifer 1 9 1 Evadne sp. Penilia 736 avirostris 96 Podon sp. 32 Insecta 2 8 Corixidae 1 Coleoptera Dytiscidae 1 1 Odonata 1 Buguia neretina P Ophiuroidea OPH 2 Oikopleura sp. 8 996 8 Branchiostoma sp. 1 Sagitta enflata 32 1 Sagitta tenuis 228 18 Osteichthyes EGG 20 732 22 Osteichthyes EAR 52 74 14 175 21 3 Clupeitbrmes LAR 4 Elopidae LEP 1 ALherinidae Mernbras LAR 14 nwrtinica 1 Anchoa ntitchilU JUV 15 Syngnathus sp. Syngnathus JUV 1 scovelli 1 Coscinodiscus sp. Wolffia P P P Columbiana Wolffiella P P floridana P P P *See Table 3 **See Table 3 By June, the species composition of plankton in area IV more closely resembled a coastal estuarine-marine fauna, though limnetic and oligohaline species continued to dominate samples from areas near freshwater runoff until July. Neritic copepods appearing in June included Labidocera aestiva, Centropages furcatus, Eiicalanus pileatus, Corycaeus americams and Corycaeus aniazonicus. Among the many hydromedusae collected in July were Liriope tetraphylla, Bougainvillia carolinensh, Fhialidium languidum, Eirene pyramidalis and Eutima variahilis. Three species of marine cladocerans {Fodon sp., Evadne sp., Penilia avirostris) and two coastal marine chaetognaths (Sagitta tenuis, Sagitta enflata) were identified. The larvacean Oikopleura sp, was present in both months. The composition of the meroplankton also changed markedly in June and July with the appearance of larval stages of Upogebia af finis, Acetes carolinae, Callianassa sp., Panopeus herbstii, Panopeus occidentalis and Menippe mercenaria. Summary Area IV. Plankton samples from the mouth of St. Louis Bay and Cat Island Pass for the period May Ihrougli September 1971 were examined by the junior author. The general composition of the plankton near the mouth of St. Louis Bay was similar for the five months, with die holoplankton dominated by A. tonsa and the mero- plankton by the zoeae of caridean shrimp and the xanthid crab R. harrisii. Assuming the above to be representative of tlie plankton in this area during the warmer months, changes in species composition at stations 1 1 and 1 2 brought about by the floodwaters include the addition of numerous oligolialine and limnetic genera. Plankton samples from Cat Island Pass in 1971 exliibited an estuarine-marine fauna. Holoplanktonic species included the neritic copepodsL. aestiva and C. furcatus and the eury- haline A. tonsa. Hydrozoan medusae were present. Perry ( 1 975) found Callincctes sp. zoeae in samples from Cat Island Pass in the spring and summer. In addition to the larval stages of Callinectes sp., the larvae of Trachypenaeus 'ip.^Penaeus sp., Lolligunada brevis and numerous sciaenid and clupeid fishes have been identified from surface tows inCatlslandPass (personal communication, Ronald Herring, Fisheries Research and Development Section, Gulf Coast Research Laboratory). These studies support the author’s assumption that the species composition of the plankton in the Cat l.sland Pass area is typically estuarine-marine, thus the effect of flood- waters at stations nearest the influence of Gulf Waters was most evident in April and May. Recovery of the system began in June with the return of estuarine-marine species. AREA V Seven stations were located in area V (Figure 3, Table 1). Stations 20 and 23 were in passes connecting shallow coastal lakes with the Gulf of Mexico. The remaining stations ranged as far as ten miles inland. Sampling in Terrebonne Parish was limited to a single trip in each of the following months: May, June and July. Station 23 was not visited in May. Bottom sediments are primarily clayey silt (Barret et al. 1971b). Submerged vegetation is sparse, but some widgeon- grass [Ruppia maritima) is present. The area is mainly saline marsh with oystergrass (Spartina alterniflora), saltgrass (Distichlis spicatd) and wiregrass (Spartina patens) predom- inating (Chabreck 1972). Water depths are shallow in the lakes ranging from 2 to 5 feet. Depths in the passes vary from 17 to 20 feet. Hydrographic Data Salinity. Preflood surface salinities at the mouth of Oyster Bayouin June and July 1968 were 15.3 and 16.4 ppt, 122 Hawes and Perry respectively, with salinities from Bayou Grand Caillou ranging from 1 4.2 to 2 1 .2 ppt from May through July 1 969 (personal communication, Marilyn Gillespie^ Louisiana Wildlife and Fisheries Commission). Under normal conditions, stations in area V would be expected to have some of the highest salin- ities of any of the areas studied. Salinity intrusion is occurring in Terrebonne Parish due to a multiplicity of factors: subsi- dence, the dredging of passes and the construction of canals. Surface salinities for stations in area V from May through July 1973 are shown in Table 10. Table 10. Hydrographic data and settled volume of plankton for stations in area V. Station Parameter May June July 17 ppt 0.3 0.1 0.0 18 ppt 0.1 0.1 0.0 19 ppt 0.3 3.3 2.0 20 ppt 0.7 3.8 7.9 21 ppt 1.5 3.2 0.3 22 ppt 2.5 6.1 1.4 23 ppt 0.0 0.0 17 "c 26.0 29.8 32.6 18 “c 26.0 29.1 31.2 19 "c 26.5 29.8 30.3 20 °c 28.0 30.1 30.4 21 °c 27.0 30.5 30.3 22 "c 28.0 30.7 31.3 23 °c 29.0 29.4 17 ml ♦1.0 2.0 ♦1.0 18 ml ♦1.0 ♦1.0 ♦1.0 19 ml *1.0 2.0 *1.0 20 ml *1.0 4.0 *1.0 21 ml 2.0 1.0 *1.0 22 ml 3.0 12.0 ♦1.0 23 ml *1.0 ♦1.0 ♦less than During the May sampling, salinities ranged from 0.1 to 2.5 ppt with the highest salinities recorded at the eastern- most stations (21 and 22). Salinities were 0.1 ppt at the inland stations 17 and 18, and 0.0 ppt in Four League Bay (station 23) in June with salinities 3.2 or above at the remaining stations. In July, all salinities were 2.0 ppt or below with the exception of station 20. The pass at Grand Bayou du Large had a reading of 7.9 ppt, the highest salinity recorded in area V during the sampling period. No postflood data were available on salinities from south- west Terrebonne parish. Temperature. Surface temperatures for stations in area V for May through July 1973 are shown in Table 10. Tem- peratures appear to be within the normal range for the area. Biological Data Settled Volume. Settled volume of zooplankton by station in area V is shown in Table 10. Settled volume was less than 1.0 ml in 13 of the 20 samples. Large numbers of Acartia tonsa and Uca sp. zoeae contributed to the high settled volume at station 22 in June. Zooplankton. A systematic list of zooplankton collected in area V is found in Table 1 1. Area data incorporating sam- ples from Grand Pass des llettes. Bayou Grand Caillou, Grand Bayou du Large, Taylor’s Bayou and Oyster Bayou in 1968-1969 were published in Gillespie (1971); however, the individual station data provided to the authors were not pubhshed. Her collections show the estuarine copepod A. tonsa and cteiiophores to dominate the holoplankton. Other holoplankters such as Labidocera aestiva and Eurytemora sp. were occasionally present in small numbers. Marine cala- noids, including species of Eucalanus, Temora and Centro- pages, entered the area in July although there was no distinct increase in salinity. The meroplankton was dominated by the larvae and postlarvae of decapods. Adult Palaernonetes sp. were collected in small numbers. Table 11. Systematic list of zooplankton, area V. Species Stage May June July Pelecypoda EAR* 1 Gastropoda EAR 6 369 10 Polychaeta 1 Polychaeta EAR 64 32 Nereis sp. 6 Hydracaiina 285 207 21 Arachnida 2 Ostracoda 142 5,415 5 Copepoda NAU 64 18 Copepoda COP 3 145 3 Acartia tonsa 3,359 118,176 88 Eurytemora affinis 144 1 Eurytemora hirundoides 8 Eurytemora sp. 8 Pseudodiaptomus cornutus 11 Diapiomus sp. 70 51 5 Labidocera aestiva 5 Harpacticoida 1 Euterpina acutifrons 8 221 Cyclopoida 12 105 Cyclops sp. 89 36 Ergasilus sp. 23 444 Halicyclops fosteri 5 Argulus sp. 37 100 19 Cirripedia NAU 196 2,128 Corophium sp. Corophium lacustre Corophium louisianum 7 14 3 EFFECTS OF 1973 FLOODWATERS ON PLANKTON 123 TABLE 1 1 — Continued Species Stage May June July Gammarus mucronatus 3 Melita nitida 1 Cerapus sp. 2 2 Isopoda 15 Muna reynoldsi 1 Edotea sp. 34 Caridea ZOE 464 230 70 Palaemonetes pugio 3 Macrobrachium ohione 1 Callinectes sapidus JUV 7 28 2 Rhithropanopeus harrisii ZOE 2,147 2,707 544 Rhithropanopeus harrisii MEG 6 1 Uca sp. ZOE 1 ,563 28,346 34 Uca sp. MEG 11 Sesarma sp. ZOE 18 96 18 Penaeus aztecus PST 13 1 Callianassa sp. ZOE 72 Upogebia a f finis ZOE 8 Diaphanosoma brachyurum 27 54 Moinodaphnia macleayii 2 Ilyocryptus spinifer 29 15 3 Sida crystallina 8 Sirnocephalus vetulus 16 2 Sirnocephalus exspinosus 7 3 Moina micrura 2 Moina affbits 2 Moina macrocopa 8 Ceriodaphnia megalops 2 1 Bosmina coregoni 2 89 Bosrnina tongirosiris 5 Insecta 1 5 Tendipedidae EAR 1 Trichoptcra EAR 1 Osteiclithyes EAR 307 136 17 .Anchoa mit chilli EAR 2 1 Anchoa mitchilli 2 Adenia xenica 3 Coscinodiscus sp. P” Wolffia Columbiana P Wolffiella floridana P P Myriophyllurn sp. P Najas sp. P Lemna sp. P *See Table 3 ’♦See Table 3 Estuarine species dominated the May, June and July samples following the 1973 opening of the Morganza Flood- way. Acartia tonsa was the most abundant holoplankter. The meroplankton was composed primarily of the zoeal stages of Rhithropanopeus harrhii and Uca sp. Numerous freshwater species were collected; however, none were present in large numbers. Members of the order llydra- carina were coitunon as well as the freshwater copepods Diaptomus sp. and Cyclops sp. Twelve species of freshwater cladocerans were noted, with Jlyocryptus spinifer, Diaphari- osoma brachyunirn and Sirnocephalus vetulus the more numerous. Freshwater plants including duckweed {Wolffiella floridam) and water meal {\^*olffia columbiand) occurred. Species diversity and abundance dropped in July. Summary of Area V. Gillespie’s data show the spring and summer plankton populations in area V to be dominated by the copepod A. tonsa and the nieroplanktonic larvae of benthic invertebrates, with marine organisms entering the area in July. During the 1973 opening of the Morganza Floodway, freshwater copepods and cladocerans augmented the normal planktonic fauna. The usual July intrusion of marine species was not observed. GENERAL SUMMARY The 1973 opening of the Bonnet Carre and Morganza floodways had a dramatic but short-term impact on plankton populations in adjacent coastal waters. Plankton populations in the estuarine w'aiers of Mississippi and Louisiana are gen- erally endemic assemblages, with the holoplankton domin- ated by Acartia tonsa and the meroplankton by the larvae of benthic crustaceans. Higher salinity portions of these estuarine areas normally show an increase in marine forms as salinities rise through the summer. During and subsequent to the floodway openings, however, the normal estuarine populations were augmented by the addition of numerous freshwater-oligohaline species. As salinities returned to normal levels, these forms were eliminated. REFERENCES CITED Barrett, B. B., J. W. Tarver, W. R. Latapie, J. F. PoUard, W. R. Mock, G. B. Adkins, W. J. Gaidry, C. J. White & J. S. Mathis. 1971a. Cooperative Gulf of Mexico Estuarine Inventory and Study, Loui- siana. Phase JI, Hydrology. Louisiana Wildlife and Fisheries Com- mission, New Orleans, Louisiana, 130 pp, Barrett, B, B., J. W. Tarver, W. R. Latapie, J. F. Pollard, W. R. Mock, G, B, Adkins, W. J. Gaidry & C. J, White, 1971b. Cooperative Gulf of Mexico Estuarine Inventory and Study, Louisiana. Phase III, Sedimentology. Louisiana Wildlife and Fisheries Commission, New Orleans, Louisiana, 61 pp. Barrett, B. B. 1976. An inventory and study of the Lake Pontchar- train Lake Maurepas estuarine complex. Phase IV. Sedimen- 124 Hawes and Perry tology , grain size analysis of bottom sediments in Lake Maurepas and Pontchartrain. Louisiana WildL and Fish. Com. Tech, Bull. 19:145-159. Bowman, T. E. \96S.Mysidopsis almyra,d. new estuarine mysid crus- tacean from Louisiana and ?lo^\d^..TulaneStud.Zool, 1 2(1):15-18. Bryan, C. F., F. M. Truesdale, D. F. Sabins & C. R. Demas. 1974. Preliminary report, a limnological survey of the Atchafalaya Basin. Louisiana Cooperative Fislieiy Unit, School of Forestry and Wildlife Management, Louisiana State University, Baton Rouge, Louisiana, 51 pp. Burke, W. D. 1975, Pelagic Cnidaria of Mississippi Sound and adja- cent waters. Gulf Res. Repi. 5(l):23-38. Butler, P. A. 1952. Effect of floodwatcrs on oysters in Mississippi Sound in 1950. U.S. Fish Wildi Serv. Res. Rep. 31 :1 -20. Cali, F. J. III. 1972. Ecology of a brackish pond system in soutli- eastern Louisiana. Master’s Thesis. Louisiana State University Library, New Orleans, Louisiana, 62 pp. Chabreck, R. H. 1972. Vegetation, water and soil characteristics of the Louisiana coastal region. La. Agric, Exp. Stn. Bull, 64:1-72. Chien, S. H. 1969. Summer Gadocera of the Pearl River system. Master’s Thesis. Mississippi State University Library, Slarkville, Mississippi, 1 37 pp. Christmas, J. Y. & C. K. Eleuterius. 1973. Hydrology. Pp, 75 121. In: J. Y. Christmas (ed.), Gulf of Mexico Estuarine Inventory and Study, Mississippi. Gulf Coast Research Laboratory, Ocean Springs, Mississippi. Cuzon du Rest, R. P. 1963. Distribution of the zooplankton in tlie salt mar.shes of southeastern Louisiana. Puhl. Inst. Mar. Sci. Univ. Tex. 9:132-155. Darnell, R. M. 1958. Food habits of fishes and larger invertebrates of Lake Pontchartrain, Louisiana, an estuarine community. Publ. Inst. Mar. Sci. Univ. Tex. 5:353 -4 1 6. . 1959. Studies of the life history of the blue crab (Callin- ectes sapidus Rathbun) in Louisiana waters. Trans. Am. Fish. Soc. 88(4) :294- 304. . 1961. Trophic spectrum of an estuarine community based on studies of Lake Pontchartrain, Louisiana. Ecology 42:553-568. . 1962. Ecological history of Lake Pontchartrain, an estuarine community, yfm. Midi. Nat. 68:434-444. Dotson, M. 1966. An introductory plankton survey of the Grand Lake, Atchafalaya Basin. Master’s Thesis, University of Missis- sippi Library, Oxford, Mississippi, 85 pp. Eleuterius, C, K, 1916. Mississippi Sound, Salinity Distribution and Indicated Flow Patterns. Mississippi- Alabama Sea Grant Consor- tium Publication No, MASGP-76-023, 128 pp. El Sayed, S. 2,, K. M. Rae, A, C. Duxbury & H, C. Loesch. 1961. Hydrological and biological studies of the Mi.ssissippi River-Gulf Outlet Project. I'exas A&M Research Foundation, Project 236, Reference 6 1 -20F. Gillespie, M, C. 1971. Cooperative Gulf of Mexico Estuarine Inven- tory and Study, Louisiana. Phase IV, Biology. Analyses and treat- ment of zooplankton of estuarine waters of Louisiana. Louisiana Wildlife and FisheriesCommission.NewOrleans.Louisiana. J 75 pp. Grice, G, D. 1956. A qualitative and quantitative seasonal study of the Copepoda of Alligator Harbor, Fla. Sta. Univ. Stud. 22(2): 37-76. Hopkins, T. L. 1966. Plankton of the St. Andrew Bay system of Florida. Publ. Inst. Mar. Sci. Univ. Tex. 11:1 2-64. Perry, 11. M. & J. Y. Christmas. 1973. Estuarine zooplankton, Mississippi, Pp. 198-254. In; J. Y. Christmas (ed.), Gulf of Mexico Estuarine Inventory and Study, Mississippi. Gulf Coast Research Laboratory, Ocean Springs, Mississippi. Perry, H. M. 1975. The blue crab fishery in Mississippi. Gulf Res. Rept. 5(I);39-57. Stern, D. IL, B. 11. Atwell, E. L. Mcrz & M. J. Verct. 1968. A summer limnological study of Lake Pontchartrain, Louisiana. Louisiana Water Resources Institute, Baton Rouge, Louisiana. Tech. Rep. 3:1-83. Sc M. Stern. 1969. Physical, chemical, bacterial and plankton dynamics of Lake Pontchartrain, Louisiana. Louisiana Water Resources Institute, Baton Rouge, Louisiana. Tech. Rept. 4:1-60. Suttkus, R. D., R. M. Darnell & J, II. Darnell. 1953-55. Biological study of Lake Pontchartrain. Research Progress Reports a j. Louisiana Wildlife and Fisheries Commission, New Orleans, Louisiana, (miiltilithed). Tarver, J. W. & R. J. Dugas. 1973. A study of the clam, Rangia cuncata, in Lake Pontchartrain and Lake Maurepas, Louisiana. Louisiana Wildl. and Fish. Com., Tech. Bull. 5:1-97, & L. B. Savoie. 1976. An inventory and study of the Lake Punlqhartrain-Lake Maurepas estuarine complex, Phases I— 111. Area descriptions, biology and hydrology and water chemistry. Louisiana Wildl. and Fish. Com,, Tech. Bull. 19:1-144. U.S. Army Corps of Engineers. 1974 -75-76. Continuous Salinity Records. New Orleans District Office, New Oxlean-s, Louisiana. Wilson, M. S. 1958. Tlie copepod genus Ilalicyclops m North Amer- ica, with a description of a new species from Lake Pontchartrain, Louisiana and ihe Texas coast. TulaneStud. Zool. 6(4):! 76-189. Gulf Research Reports Volume 6 | Issue 2 January 1978 An Improved^ Conceptually Simple Technique for Estimating the Productivity of Marsh Vascular Flora Courtney T. Hackney University of Southwestern Louisiana Olga P. Hackney Mississippi State University DOI: 10.18785/grr.0602.02 Follow this and additional works at: http:/ / aquila.usm.edu/ gcr Part of the Marine Biology Commons Recommended Citation Hackney, C. T. and O. P. Hackney. 1978. An Improved, Conceptually Simple Technique for Estimating the Productivity of Marsh Vascular Flora. Gulf Research Reports 6 (2): 125-129. Retrieved from http://aquila.usm.edu/gcr /vol6/iss2/2 This Article is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf and Caribbean Research by an authorized editor ofThe Aquila Digital Community. For more information, please contact Joshua.Cromwell^usm.edu. Gulf Research Reports, Vol. 6, No. 2, 125-129, 1978 AN IMPROVED, CONCEPTUALLY SIMPLE TECHNIQUE FOR ESTIMATING THE PRODUCTIVITY OF MARSH VASCULAR FLORA COURTNEY T. HACKNEY AND OLGA P. HACKNEY Department of Biology, University of Southwestern Louisiana, Lafayette, Louisiana 70504 and Department of Computer Science and Statistics, Mississippi State University, Mississippi State, Mississippi 39762 ABSTRACT The estimatiou of tlic net primary productivity of marsh communiiies with a periodic maximum -minimum (PMM) technique has certain advantages over the long used maximum- minimum standing stock technique, but still retains the same conceptual simplicity. The final productivity estimate with PMM is based on the entire data set rather than just two points. Direct statistical comparisons between any two oommunUie'! can be made. An estimate of the productivity by minor species in the couuuujiity can also be made. The periodic model permits statistical comparisons about other variables in com- munity growth such as the timing of the maximum standing crop. With certain assumptions, productivity estimates which account for the loss of live plant material during Uie growing season can be made without the tremendous amount of effort and . time required by the Wiegeri-Evans technique. Despite the increased utility the PMM technique requires no additional field effort. INTRODUCTION The productivity of coastal tidal marshes is a useful way to compare the potential productivity of estuaries (Turner 1977). Estimation techniques for tidal marsh productivity range from conceptually simple techniques such as the standard maxiinum— minimum (max— min) standing crop technique to techniques that measure the disappearance of material from plots in addition to the increa.se in living plant material (W'iegerl and Evans 1964). Each technique has certain advantages over other techniques. The Wiegert— Evans technique may provide a better estimate of plant productivity, but requires more time and effort than the standard max— min technique. Determination of the best technique depends greatly on the amount of effort available, the community to be studied, and the eventual use of the data. The ideal technique must account for (1) the variation of plant density throughout the study marsh ;(2) the inherent variation between sampling dates; (3) the death of new plant growth during the growing season; (4) the productivity of minor plant species in the community ; and (5) loss of new plant growth through herbivory. The following is a method for estimating marsh plant productivity using the conceptual simplicity of the max— min technique, but allows the researcher to account for these other variable^; in his estimate. The use of a statistical model improves the reliability of the productivity estimate and provides a valid mathematical model through which other tests and comprisons can be made. These advantages are added without substantially increasing the amount of effort required for the max— min technique. The technique also has the advantage of allowing straight-forward statistical com- Manusciipt received May 22, 1978; accepted August 15, 1978. parisons between any two studies regardless of when or where they are made. The periodic model has widespread application and has provided a good fit for many other bio- logical phenomena (Odum and Smalley 1959; Buzas 1969; Brown and Taylor 1971 ; Hackney et al. 1976). METHOD The periodic regression model differs from the usual general regression model only in the functional form of the independent variable. The usual general one-term linear regression model is: y^ = a + j3x^ + ej i = 1, . . . , n. The corresponding one-term periodic model considers the trigonometric functions of Xj as y^ = 0(0 + 0(1 cos (ex-) + /3i sin (exj) + Cj (1) where yj = dependent variable Oq = constant parameter , /3i = coefficients of the harmonic function of Xj c = 'htln Xj = i th independent variable Cj = error. Note that a pair of trigonometric terms constitute a single harmonic term. In most ecological problems the independ- ent variable x- is time, each x- representing a unit of time such as months, i = 1, 2, . . . , 12. The dependent variable y- could be temperature, salinity, number of organisms, etc. The semi-amplitude of the curve described in equation (1) would be A = Q? +i3^ 125 126 Hackney and Hackney and the phase angle estimated by Tan(0) = l5i/a, [ . The number of terms in the model is determined in the same manner as choosing the number of terms in any regres- sion model. The goal is to find a model that adequately describes the data, and also has biological validity. As in polynomial regression, it is possible to add enough terms to the periodic model to achieve an exact fit. The addition of harmonic terms should depend upon the biological inter- pretation of the model. If only the diel cycle is known to effect a given phenomenon yet five harmonics are required to explain the data, then the model is probably incorrect. Other factors, not necessarily periodic, might need to be considered in the model. The periodic model usually pro- vides an excellent fit for productivity data (Bliss 1970; Hackney and Hackney 1977). This technique allows the u.se of stratified sampling collection procedures which are less destructive to marshes than simple random collection tech- niques and less time consuming. Since the fitted curve used samples collected over the entire marsh, the final resulting max— min values reflect the variation in plant density within the marsh as well as the inherent error between samples. The standard max-min procedure only reflects the variation of the highest and lowest biomass estimates. Estimation of the productivity of minor species can be made using the same periodic curve with these same conceptual advantages overcoming the usual patchiness of minor plant species distribution, essentially integrating this highly variable com- ponent into a smooth curve. If data are available on the death rate of plants within the community, a productivity estimate may be obtained that, like the Wiegcrt— Evans technique, includes productivity lost by the early death of plants. In many cases these data are available with little increase in effort. Examples The data used in the following examples were collected in a Mississippi tidal marsh located on the western side of St. Louis Bay, Mississippi. The vegetation on this marsh was described by Gabriel and de la Cruz (1974). The increase of above-ground vascular plant biomass in marshes usually follows a periodic type of curve as does the increase in the below-ground portions of these plants (de la Cruz and Hackney 1977). An examination of the means of each collection plotted against time will provide visual proof of whether the periodic model is appropriate. In the following examples five 0.25 m^ samples were collected on each date. The first example demonstrates what factors are used to determine the validity of the model and the differ- ence between a productivity estimate made through the periodic max— min technique and an estimate with the standard max-min technique. The second example provides a mathematically sound method of estimating the contribu- tion by minor plant species in the community, while the third example compares two models that produced similar quanti- ties of biomass, but produced them at different times.The last example shows how a better productivity estimate can be ob- tained if information on the death rate of the plants is known. One disadvantage of the traditional max-min technique is that it uses onlytwovaluesfromtheentire year’s collection, the highest and lowest standing crop of living plant material. With this technique the conununiTy in Figure 1 had a pro- ductivity of 481 g/m*/yr. A periodic curve fitted to all of the data points also provides a maximum and minimum value, but these values are based on the entire data set and the variability of all samples. There were 372 g/m^/yr of vascular plant production estimated by this technique. The periodic model of theJuncus community in Figure 1 is Y = 770.9 -88.7 sin (ctp- 162.9 cos (ct-) where c = 27r/l 2 and 1. = 1 , , . . , 12 based on 40 obser- vations. The r^ was 0.493 with a significant F of 18.0 which indicates a significant (a = 0.05) periodic compon- nent and a significant r^ in the data set. The test of a signif- icant periodic component is the most important factor when deciding whether to accept the use of the periodic model. If this component were nonsignificant a model based just on the overall mean would be more appropriate. More information on the actual testing of periodic models is provided by Hackney and Hackney (1977). The variability of plant distribution within a marsh plant community may cause what seems to be iow r^ values. This variability affects the r“ most if a random stratified sampling scheme is used. If one is willing to accept the assumption that the .4 I D F A J A 1977 Figure 1, Monthly changes of tirve biomass in a Juncus community. Vertical lines represent ± one standard error. The smootli curve is predicted from the periodic model. E.slimatcs derived by the simple max-min technique and the periodic model are compared. Estimating Productivity of Marsh Flora 127 increase in plant biomass follows a periodic pattern then a random stratified sampling procedure may be used, which does not disturb the marsh, and is not as time consuming as the simple random collection technique. Perhaps the most difficult component to isolate in a marsh plant community is the contribution of the minor species to tbe productivity of the community. This may be done through the development of a periodic model for the increase of living plant biomass for the entire community, and a separate model for the dominant plant species, in this example Jimcus roemerianus (Figure 2). Subtraction of the two productivity eslimate.s yields an estimate of the contribution by the minor plant species in the community, which ill this case was 56 g/m^/yr. 1976 1977 Figure 2. Periodic models of the total live plant biomass and the total live Juncus in a control community. Tbe mean of each monthly collection is provided for comparison. 'Fhe difference between the productivity estimates is an estimate of the productivity of the minor species in the community. Another useful aspect of this technique is the ability to test whether the growth (productivity) of two communities is the same. Using the standard max— min technique one has two numbers to compare and no way to make a statement about any statistically significant differences between the two communities. In the following example, two Spartina cynomroides communities were compared the second year following a bum in one community (Figure 3). A compar’ ison of the two periodic models indicated that there was no significant difference (a = 0.05) in fhe amount of live bio- mass produced, but that the peak production was reached earlier in the burned community. This type of information is not available directly from other estimation techniques. Interpretation of the analysis of variance (ANOVA) output necessary to make these decisions is provided by Hackney and Hackney (1977). Despite the reliability realized through the use of this periodic max- min technique there are still certain com- ponents of plant productivity that are not considered. Hopkinson et al. (in press) emphasized the need for any Figure 3. Periodic models of the natural and burned Spartina cynosuroides community. Individual points represent the mean ± one standard error. productivity estimate to account for the loss of dead plant material from a community. Tliis is most important if the above-ground portions of the plant do not die during the winter, such as J. roemerianus along the Gulf coast or if the turnover rate is very high. To integrate this component into a periodic max— min estimate one can produce a mathemat- ical model based on the accumulation of dead material during the growing season. It is necessary to be sure that this dead material was produced during the growing season. To do this an area can be cut at the beginning of the grow- ing season and samples collected from this area each month. In the case of plants that die each winter, cutting does not seem to affect the accumulation of dead material during the growing season. The only potential effect is the lack of shading that may be produced by the previous year’s dead standing biomass. In the case of perennial plants {Juncus^ etc.) which stay green all year this practice may have some effect. The addition of this component to the productivity 128 Hackney and Hackney estimate may require the addition of a significant amount of field work to the study. In the following example this was not a factor since the intent was to estimate the pro- ductivity of ^Juncus community following a fire. A general model that combined a periodic component with an asymp- totic exponential function provided a good fit for the increase of dead material in the burned Juncus community. Models besides the asymptotic exponential would be ade- quate provided that they adequately represent the data. The predicted model of the live biomass, dead biomass and the combined model (Figure 4) illustrates the need to account for this dead component. In this particular case 1 1 5 g/m^ was added to the annual productivity of this community by accounting for the loss of new living material during the growing season. 1976 Figure 4. Periodic model of the living plant biomass, model of the accumulation of dead plant material and the combined value of a burned Juncus community. DISCUSSION The measurement of net primary productivity in any marsh system is necessary to completely understand the energetics of that system. Techniques that measure other factors besides changes of live biomass (Wiegert and Evans 1 964) may be useful if the additional time and effort are available. It is unlikely that the literature on marsh plant productivity will ever achieve I he uniformity that Turner (1976) and Kirby and Gosselink (1976) feel is necessary when other researchers consider the max— min technique adequate (de la Cruz 1978). The periodic max -min tech- nique (PMM) could provide uniform estimates of marsh plant productivity since most of the published data could easily be recalculated using this technique. The technique still possesses the conceptual simplicity which de la Cruz (1978) believed desirable. With only a small amount of increased effort other factors such as the instantaneous loss rate, productivity of minor species in the community, and various sampling problems can be accommodated with the PMM technique. Kirby and Gosselink (1976) fitted a poly- nomial function to the changes of live and dead material they found in a salt marsh. These data could have been easily fitted to a periodic model. The biological interpre- tation of a polynomial model is not usually apparent, while the interpretation of a periodic model is usually straight forward. For example, a fourth-degree polynomial is equiva- lent to a single harmonic model. Interpreting the meaning of raising an independent variable, e.g., time, to the fourth power is more difficult than explaining a single cycle over a specified interval. Also direct estimates of amplitude and phase are available. Periodic models may also reveal differ- ences between communities via periodic regression analysis (Hackney and Hackney 1977). The calculation of the actual primary productivity of marsh plants is difficult. In the past we have separated the productivity of the aerial portion of the plant (leaves and stems) from the productivity of the roots and rhizomes. This below-ground productivity may be as high as the above- ground productivity (de la Cruz and Hackney 1977). More recently Hopkinson et al. (in press) have shown that pro- ductivity estimates that do not consider the short-term turn- over rate may greatly underestimate the primai'y productivity of some marsh plant species. The estimation of the loss of newly produced plant material (instantaneous loss rate) in a marsh community has many associated problems (Hopkinson et al,, in press), A relatively simple method of estimating this loss rate is shown in Figure 4. This technique would not be appropriate for plants with a rapid turnover rate and would not be as good an estimate as that obtained by the paired plot technique of Hopkinson et al. (in press). Both techniques require the disturbance of an area by the researcher that could affect the final results. The effect of clipping all vegetation from an area and then following the accumulation of dead material during the growing season may not affect the resultant estimate any more than the variables introduced by the Wiegert— Evans technique. Hopkinson et al. (in press) suggested that the max— min technique underestimated the actual productivity of marshes because it docs not account for the loss of newly produced organic matter. An additional criticism of the standard max— min technique is that if provides a poor estimate of the actual increase of living plant biomass because it is based on only two points, each of which is subject to the inhereni Estimating productivity of Marsh Flora 129 variability found in any natural system (Figure 1). The periodic max— min technique provides an estimate that is based on every sample collected during the study. Thus, the primary productivity estimate obtained through the periodic max— min technique may be higher or lower than the standard max— min technique, but is far more reliable. If the model which predicts the loss of new plant growth is added to tlie periodic model, an estimate is produced that is higher than either of the max—min estimates and compar- able to the Wiegert— Evans technique. Since the periodic max— min technique is easy to use, conceptually simple, and satisfies some of the criticisms of other techniques, it is suggested as the best general method available to estimate the net primary productivity in marsh communities. ACKNOWLEDGM ENTS These data were collected througli a grant provided by the Mississippi Marine Resources Council (OR— 76— 003). REFERENCES CITED Bliss, C. I. 1970. Statistics in Biology. McGraw-Hill Co., New York. 639 pp. Brown, E. S. & L. R, Taylor. 1971. Lunar cycles in the distribution and abundance of albino insects in the equatorial highlands of east Africa./. Anim. Ecol. 40:161-^111 . Buzas, M. A. 1969. Foraminiferal species densities and environ- mental variables in an estuary . Ltmrto/. Oceanogr. 1 4 :4 1 1 -4 22. de la Cruz, A. A. 1978. Present status and future needs of primary production studies in freshwater wetlands, Pp. 79-88 in R. E. Good, D.F. Whigham, R.H. Simpson and C.G. Jackson, ir., eds,, Symposium on Freshwater Marshes: Ecological Processes and Management Potential. Academic Press, New York. & C. T. Hackney. 1977. Energy value, elemental compo- sition, and productivity of below ground biomass of a Juncus tidal marsh. Ecology 58:1 1 65-11 70. Gabriel, B. C. and A, A. de la Cruz. 1974. Species composition, standing slock and net primary productivity of a salt marsh community in Mississippi. Chesapeake Sci. 15:72-77. Hackney, C. T,, W, D. Burbanck & O. P. Hackney, 1976. Biological and physical dynamics of a Georgia tidal creek. Chesapeake Sci. 17:271-280, Hackney, O. P. &. C. T, Hackney, 1977. Periodic regression analysis of ecological data./. Miss. Acad. Sci. XX1I;25~33, Hopkinson, C. S., J. G. Gosselink & R. T. Parrando, Aboveground production of seven marsh plant species in coastal Louisiana. Ecology, in press. Kirby, J. J, & 1. G. Gosselink, 1976. Primary production in a Loui- siana Gulf coast Spartina alterniflora marsh. Ecology 57:1052-1059- Odum, E. P. & A. E. Smalley. 1959. Comparison of population energy flow of a herbivorous and a deposite feeding invertebrate in a salt marsh ecosystem. Flroc. Natl. Acad. Sci. Lf.S-A. V:45. Turner, R. E. 1976. Geographic variation in salt marsh macrophyte production: Arenew. Contrib. Mar. Sci. 20:47-68. ■ 1977. Intertidal vegetation and commercial yields of penaeid shrimp. 7>ans. Am. Fish Soc. 106:411 416. Wiegert, R. & F. Evans. 1964. Primary production and the disappear- ance of dead vegetation on an old field. Ecology 45:16—63. Gulf Research Reports Volume 6 | Issue 2 January 1978 Food of the Red Drum^ Sciaenops ocellata, from Mississippi Sound Robin M. Overstreet Gulf Coast Research Laboratory Richard W Heard Gulf Coast Research Laboratory DOI: 10.18785/grr.0602.03 Follow this and additional works at: http:/ / aquila.usm.edu/ gcr Part of the Marine Biology Commons Recommended Citation Overstreet, R. M. and R. W. Heard. 1978. Food of the Red Drum, Sciaenops ocellata, from Mississippi Sound. Gulf Research Reports 6 (2); 131-135. Retrieved from http;//aquila.usm.edu/gcr/vol6/iss2/3 This Article is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf and Caribbean Research by an authorized editor ofThe Aquila Digital Community. For more information, please contact Joshua.Cromwell^usm.edu. Gulf Research Reports. Vol. 6, No, 2, 131-1 35, 1978 FOOD OF THE RED DRUM, SCIAENOPS OCELLATA , FROM MISSISSIPPI SOUND' ROBIN M. OVERSTREET AND RICHARD W. HEARD Parasitology Section, Gulf Coast Research Laboratory, Ocean Springs, Mississippi 39564 ABSTRACT Examined digestive tracts of the red drum in Mississippi Sound contained mostly decapod crustaceans. Crustaceans accounted for 34 of 59 encountered taxa, more than reported from any other region. Nevertheless, the general diet for 104 fish with food contents out of the 107 examined is similar to that reported for red drum in several other studies from other areas. In addition to crustaceans, fishes followed by polychaetes occurred as the most important items (in 99, 43, and 15% of the drum with food, respectively). Blue crabs occurred in even more drum than the frequently encountered penaeid shrimps. Other commercial species were negligible in the diet. Sixteen large drum from Georgia beaches were also examined; unlike those from Mtssi.ssippi, many of these contained cchinoderms, but not polychaetes or penaeids. We suggest that the red drum’s migrations may be regulated by optimal abundance of specific types of dietary organisms. INTRODUCTION The red drum, Sciaenops ocellata^ also corninonly called redfish or channel bass, is an important sportsfish in Missis- sippi coastal waters. Consequently, in order to appreciate that fish’s relationship with other organisms in the region, we investigated its specific diet in Mississippi and examined the relative extent of its predation on commercial shrimps and crabs. In the northern Gulf of Mexico, the drum typically feeds (1) in shallow marsh areas rooting about with its head lowered and its tail occasionally out of the water; (2) in relatively deep inshore water in depressions behind sand- bars or channels adjacent to mud- or grassflats (Yokel 1966), or (3) for large adults, in Gulf water, usually near shore, but occasionally several kilometers offshore. The amount of drum caught from a locality appears directly related to the locality’s amount of estuarine area (Yokel 1966). MATERIALS AND METHODS A total of 107 red drum, 104 with food in their stomachs or intestines, was collected between May 1976 and August 1977 by hook and line or gill net and placed on ice or frozen until examined. The fish came from a variety of habitats: (1) near barrier islands, (2) open water of Mississippi Sound, and (3) Davis Bayou, Biloxi Bay, and other sites adjacent to marsh grass. After taking standard lengths (SL) of fish, we either immediately identified food items orpreserved them in 10% formalin. Twenty-two additional adult drum were exam- ined from Sapelo Island, Georgia, and treated identically. RESULTS Fifty-nine different taxa plus remains of several more unidentified ones occurred in the red drum (Table 1). Most 'This study was conducted in cooperation with the U.S. Depart- ment of Commerce, NOAA, National Marine Fisheries Service, under PL 88-309, Project Nos. 2-262-R and 2-325-R. Manuscript received October 10, 1978; accepted October 17, 1978. of these were crustaceans and all but one drum with food contained at least one crustacean (99%). Even with the extensive variety in crustaceans, few of which had been reported previously as drum food, blue crabs and penaeid shrimps occurred most frequently. The commonly encount- ered penaeid and palaemonid shrimps, however, occurred in a smaller percentage of fish longer than 50 cm than of shorter fish. On the other hand, the percentages of drum with blue crabs, the stoma topod Squilla empusa, and some other items were greater in the larger fish (Table 2). Fishes, occurring in 43% of the drum, constituted the second most abundant item. These occurred more commonly in larger fish (Table 2); 65% of those drum over 50 cm had fish in their stomachs compared with 43 and 30% in the two smaller groups. Polychaetes also contributed to the diet, but appeared less important in fish over 50 cm. Other items were rare in the drum examined from Mississippi. Some seasonality in diets was apparent (Table 3). As examples, some relatively uncommon food items, annelids, echinoderms, and a bryzoan (probably ingested passively while feeding on another organism), occurred only during winter and spring, whereas the stomatopod occurred exclu- sively during spring and fall. On the other hand, when con- sidering the prevalent blue crabs and penaeid shrimps, we found the percentage of crabs was greater in spring and summer and that of the shrimps in winter and fall. The contents of 16 relatively large drum from Sapelo Island, Georgia, are listed in Table 4. DISCUSSION Even though we list many more specific food items than other reports on the red drum’s food, our findings agree generally. Pearson (1929), Gunter (1945), Kemp (1949), Miles (1 949:1 950), and Knapp ( 1 95.0) from Texas; Fontenot and Rogiilio (1970) and Boothby and Avault (1971) from Louisiana; and Yoke! (1966) from Florida all provided data on over 100 examined drum. Contents from numerous juvenile drum have also been recorded from Texas by Miles 31 132 Overstreet and Heard TABLE I. Percentage of occurrence of organisms and other material obtained from the stomachs and intestines of 104 red drum in Mississippi Sound. Food Items Occurrence (%) Food Items Occurrence (%) Polychaetes Pinnixa sp. l.p. Oxaetoplerus variopedatus tube 1,0 Porrunus gib best 5.8 Glycera americana 10.6 Processa cf. hemphilli 6.7 Nereis succinea 3.8 Rhithropanopeus harrisi 1.9 Unidentifiable polychaete 1.9 Sicyonia brevirostris 1.9 Stomatopod Sicyonia dorsalis 1.0 Squilla empusa 8.7 Speocarcinus lobarus 1.9 Amphipods Tozeutm carolinensis 1.0 Ampelisca abdila 1.0 Trachypenaeus similis 2.9 Unidentifiable ampithoid 2.9 Uca longisignalis 2.9 Decapods Unidentifiable goneplacid 3.8 Alpheus hei erochaelis 5.8 Upogebia affinis 1.0 Alpheus normonni 2.9 Ectoproct Callinectes remains 6.7 Bugula neritina 4.8 CalUnectes sapidus 17.3 Holothuroid Callinectes similis 36.5 Thyonacta mexicana 1.0 Chasmocarcinus mississip- Echinoid piensis 1.0 Mellita quinquiesperforata 3.8 Emerita talpoida 1.0 Fishes Euceramus praelongus 1.0 Achirus lineatus 1.0 Hepatus epheliticus 5.8 Anchoa mitchilli 5.8 Hexaparuipeus angustifrons 5.8 Brevoortia patronus 1.0 Hippolyte pleuracantha 3.8 Cyprinodon voriegatus 2.9 Leiolambrus nitidus 1.0 Diplectrum sp. 1.0 LepiJopa bennedicti 1.9 Gobiosoma bosci 1.9 Neopanope texana 27-9 Micropogonias undulatus 1.0 Ovalipes floridanus 2.9 Mugil ceplmlus 1.0 Palaemonetes pugio 8.7 Myrophis puncratus 8.7 Pofoemoneies vulgaris 5.8 Paralichthys lethostigma 1.0 Penaeus aziecus 3.8 Selene vomer 1.0 Pemeus duorarum 16.3 Symphurus plagiusa 4.8 Penaeus remains 6.7 Unidentifiable blenniid 1.0 Penaeus setifems 11.5 Unidentifiable fish remains 23.1 PericUmenes lungicaudatus 1.0 Unidentifiable goby 4.8 Persephona punctata aquUomris 3.8 Algae 2.9 Pinnixa chacei 1.9 Detritus 1.9 TABLE 2. Percentage of occurrence of organism-groups in the digestive tracts of 104 red drum by length-groups from Mississippi Sound. TABLE 3. Percentage of occurrence of organism-groups in the digestive tracts of 104 red drum by season from Mississippi Sound. Food Items Length of Fish in mm SL Total (%) Food Items Season otal (%) 190-349 43 fish 350^499 35 fish 500-780 26 fish Winter 30 fish Spring 34 fish Summer 26 fish Fall 14 fish T Polychaetes 18.6 17.1 7.7 15.4 Polychaetes 33.3 14.7 0.0 7.1 15.4 Bryzoan 2.3 5.7 7.7 4.8 Bryzoan 13.3 2.9 0.0 0.0 4.8 Echinoderms 0.0 2.9 11.5 3.8 Echinoderms 3.3 8.8 0.0 0.0 3.8 Stomatopod 2.3 2.9 26.9 8.7 Stomatopod 0.0 17.6 0.0 21.4 8.7 Amplupod.s 7.0 2.9 0.0 3.8 Amphipods 0.0 0.0 3.8 14.3 3.8 Penaeid shrimps 44.2 42.9 30.8 40.4 Penaeid shrimps 53.3 23.5 30.8 71.4 40.4 Palaemonid shrimps 18.6 20.0 0.0 14.4 Palaemonid shrimps 23.3 8.8 15.4 7.1 14.4 Callinectes crabs 48.8 62.9 53.8 54.8 Callinectes crabs 36.7 70.6 65.4 35.7 54.8 Other decapods 37.2 65.7 80.8 57.7 Other decapods 86.7 70.6 19.2 35.7 57.7 Fishes 30.2 42.9 65.4 43.3 Fishes 56.7 41.2 26.9 50.0 43.3 Algae 2.3 5.7 0.0 2.9 Algae 6.7 0.0 0.0 7.1 2.9 Detritus 4.7 0.0 0.0 1.9 Detritus 3.3 0.0 3.8 0.0 1.9 food of the Red Drum 133 TABLE 4. Percentage of occurrence of organisms from the digestive tracts of 16 specimens of red drum, 43 to 102 cm long, caught from June through August 1970 at different beach localities of Sapelo Island, Georgia. Food Items Occurrence (%) Molluscs Barnea truncate 6.3 Petricola photadiformis 6.3 Sinum perspectivum 6.3 Crustaceans Callinecies sapidus 31.3 Callinectes simitis 12.5 Hepatus epheUticus 6.3 Ovalipes ocellatus 12.5 Pagurus hngicorpus 6.3 Portunus gibbesi 12.5 Echinoderms Mellita quinquiesperforata 18.8 Sclerodactyla briareus 37.5 Fishes Fundulus mafalis 6.3 Leiostomus xanthurus 6.3 Menticirrhus americanus 6.3 Mugil cephalus 18.8 Opsanus tau 6.3 Trachinotus carolinus 6.3 jyinectes maculatus 6.3 Unidentified fish 6.3 (1950) and from Louisiana by Bass and Avault (1975). Other less extensive data on food items were reported by Reid (1955), Reid et al. (1956), Simmons (1957), Breuer (1957), Darnell (1958), Jnglis (1959), Springer and Wood- burn (1960), and Simmons and Breuer (1962). Bascially, crustaceans and fishes provided most of the reported food items for the red drum. Components fluctuated some because of various factors. Shrimps and crabs comprised the most frequently encounted crustaceans, and the fre- quencies of (hose organisms varied considerably. Gunter (1945) implied that crabs were eaten more in bay waters, whereas shrimp dominated the diet in and near Gulf water; Pearson (1929) considered the blue crab most important as food when small or in molting condition; Miles (1950) thought fishes and crabs became important when shrimp became scarce; Yokel (1966) found shrimp most import- ant in South Florida from July to September, but crabs most important during the other periods; Yokel also found the red drum to eat proportionally more crabs as it grew larger, with xanthid crabs gaining in importance and portunids losing in importance; and Boothby and Avault (1971) considered crabs and shrimp of equal importance in the diet. Fishes also composed an important part of the red drum’s food. Boothby and Avault (1971) found fish in 75% of the Stomachs constituting 35% of the food’s volume in a south- eastern Louisiana marsh. All other studies found fish of less importance to drum except that of Inglis (1959) who exam- ined small drum and possibly Breuer (1957) and Simmons (1957) who did not provide data. In most areas, fish appear to become less important to large drum even though often making up a significant part of the drum’s diet. Reid et al. (1956) recorded 23 menhaden in one drum. On the other hand, Pearson (1929) suggested small mullet provide the best bait for large drum, and shrimp provide it for small ones. If crabs are to be used as bait, Simmons and Breuer (1962) .said the legs should be removed and the body halved. Most feeding takes place in early morning and late evening. Our study on food contents in Mississippi Sound shows several trends. Three of these are: (1) that polychaetes, especially Glycera americana, are fairly important com- ponents, being most commonly seen in fish smaller than 50 cm; (2) that echinoderms are eaten by large fish; and (3) that many different decapods, at least 34 in number, provide food. Crabs occurred in more stomachs than shrimps, but both groups, especially commercial species, constitute heavily preyed-on organisms. Actually, the lesser blue crab, Callinectes similis, not previously reported from the red drum (except possibly by Kemp [1949] as C dame [see Williams 1974]), occurred in more fish than C sapidus (37 versus 17%). Knowledge about the habits of the decapods listed in Table 1 reveals that the red drum feeds in sandy to muddy Dottoms from both shallow and moderately deep water. A few dietary organisms such as Chasmocarcinus mississip- piensis, a commensal crab, have been observed in the locality infrequently. Most species, however, make up common components of the different ecosystems in and adjacent to Mississippi Sound. Large drum feeding near the high energy beaches of Sapelo Island, Georgia, (Table 4) reveal crustaceans and fishes as important dietary components. They, however, also feed heavily on echinoderms. Additionally, molluscs occurred, but not polychaetes. As in Mississippi, the variety of both decapods and fishes is extensive. Grassbeds also constitute an important community in which drum, especially preadults, feed. Specific animals act as indicators of fish feeding in that habitat. Some are Neopanope texana, Hippolyte pleuracantha, and Pemeus duorantrn. Other animals support feeding activities in other areas. As examples, Rhithropanopeus harrisi shows feeding from upper-bay, low-salinity areas; Uca longisigmlis from shallow mudfiats;and Emerita talpoida, Pinnixa chacei, and MeUita quinquiesperforata from open sandy beaches. The seasonality of the drum’s diet probably primarily reflects availability of the specific organisms, but some selectivity also appears evident. Fall is when shrimp, espe- cially white shrimp, are abundant and when 71% of the drum had penaeid shrimp as food contents. On the other hand, many shrimp should also be available during spring and summer. During those two seasons, blue crabs seem to 134 Overstreet and Heard have greater priority as food. When blue crabs were not prevalent during winter, various crabs and a few other miscellaneous decapods prevailed both as food contents and as common organisms in the habitat. Whereas the menhaden and mullet are the most common dietary fishes in some areas, those items were not encount- ered commonly in our food samples. In fact, the most frequently identified ilsh were the speckled worm eel and bay anchovy. Many fish could not be identified because of their digesled state. Conspicuous by their absence were gastropods, bivalves, mysids, and copepods. These, especially the latter two, both of which are crustaceans, probably occur commonly in fingerling drum from Mississippi Sound. Even thouglx the diet of red drum from some other geo- graphic regions consisted largely of individuals comprising one taxon, we did not encounter similar findings^ We, how- ever, did find 18% of the drum with a single food source and, of those, ten had a blue crab, six had a pcnacid shrimp, two had the mud crab Neopanope texana, and one had a fish. About half of those drum came from the northern part of the Sound near marsh grass and the remainder came from near the barrier islands. We did not sample small red drum; however, a few other workers have. Bass and Avault(T975),in the most extensive report, found that fish less than 30 mm fed primarily on zooplankton. As the fish reached 26 mm long, the frequency of calanoid copepods dropped off and that of rnysids increased. Little difference occurred between food contents encountered during day or night until the drum reached 65 mm when consumption of shrimp prevailed during the day contrasting with that of fish at night. Polychaetes and amphipods also accounted for considerable food. Evidence based on fewer samples by Hildebrand and Schrocder (1928), Miles (1950), Springer and Woodburn (1960), and Odum and Heald (1972) essentially corroborated the above find- ings. Inglis (1959), who examined fish 30 to 100 mm long from Texas, however, found about 80% contained fish, 10% contained amphipods, and fewer contained a variety of other organisms. Migration of red drum might be dictated by the abundance of specific food items. In other words, the drum might con- tinually migrate in a relatively consistent pattern in order to optimize specific rich food sources. Thus, fish would exploit different areas seasonally. The data from Sapelo Island, Georgia, reveal that large fish fed heavily during the summer on the five-lunuled sand dollar Mellita cfuinquiesperforata and the sea cucumber Sclerodactyla briareua near the high energy sandy beaches. We also recovered similar items in a few fishes duringMay from Mississippi, and Thomas Mcll wain (personal communication) found numerous individuals of the sea catfish, Arius felis; the sea pansy, Renilla rnuelleri; and M, quinquiesperforata in six 9- to 10-kg fish caught off Horn Island in September 1966. Possibly the fish that ate echinoderms and associated infauna were migrating to other regions with relatively underutilized crustaceans, but taking advantage of different underutilized subsurface organisms on the way. These items are probably important to the overall diet of red drum and to its natural history, ACKNOWLEDGMENTS We are grateful to the following people for aiding in var- ious aspects of the study: Ronnie Palmer, Roswitha Buxton, l.aurie Toomey, Kay Richards, Ann St. Andrie, Tom Mattis, Dan Brooks, and Beryl Heard. REFERENCES CITED Bass, R. J. & J. W. Avault, Jr. 1975, Food habits, length -weight relationship, condition factor, and growth of juvenile red drum, Sciaenops ocellata, in Louisiana. Trans. Am. Fish. Soc. 104(1); 35-45. Boothby, R. N. &. J. W, Avault, Jr. 1971. Food habits, length- weight relationship, and condition factor of the red drum, Sciaenops ocellata, in southern Louisiana. Trans. Am. Fish, Soc. 100(2):290-29S. Breuer, J. P, 1957. An ecological survey of Baffin and Alazan bays, Texas. Pw/)/. Inst. Mar. Set, llniv. Tex. 4(2): 134-1 55. Darnell, R. M, 1958. Food habits of fishes and larger invertebrates of Lake Pontch art rain, Louisiana, an estuarine community. Publ. Irrst.AIar, Set., Univ. Tex. 5:353 -416. Fontenot, B, J., Jr. & H. E. RogilJio. 1970. A study of estuarine .sportfishes in the Biloxi Marsli Complex, Louisiana. Dingell- Johnson Project F-8 Completion Report for Louisiana Wildlife and Fisheries Commission. 172 pp. Gunter, G. 1945. Studies on marine fishes of Texas. Publ Inst. Mar Scl, Univ. Tex. l(l):l-190. Hildebrand, S. F. & W. C. Schroeder. 1928. Fishes of Chesapeake Bay. Bull [U.S.j Bur. Fish. 43:1-366. Inglis, A. 1959, Predation on shrimp. U.S, Fish. Wildl Serv. Circ. 62:50-53. Kemp, R. J. 1949. Report on stomach analysis from June 1, 1949 through August 31, 1949. Tex. Game, Fish, Oyst. Comm., Alar, lab. Ann. Rep. 1948 J 949:^ -111. Knapp, F. T. 1950. Menhaden utilization in relation to the conserva- tion of food and game fishes of the Texas Gulf Coast. Trans. Am. Fish. Soc, 79:137-144, Miles, D. W. 1949, A study on food habits of the fishes of the Aran- sas Bay area, Tex. Game, Fish, Oyst. Comm,, Mar, lab. Ann. Rep. J 948-1 949:129-169. 1950. The life histories of the spotted sea trout, Cy no- scion nebuhsus, and t\\Qrc6r\s)a, Sciaenops ocellatus. Tex. Game, Fish, Oyst. Comm., Mar. Lab. Ann. Rep. J949-J930. 38 pp. Odum. W. E. & E. .T, Heald. 1972. Trophic analyses of an estuarine mangrove community. Bull Mar. Sci. 22(3):67J -738. Pearson, J. C. 1929, Natural history and conservation of the redfish and other commercial Sciacnid.s on the Texas Coast, Bull. /U.S.} Bur. Fish. 44U046);1 29-214. Reid, G. K,, Jr. 1955. A summer study of the biology and ecology of East Bay, Texas. Part 11. The fish fauna of East Bay, the Gulf beach, and summary. Tex. J. Sci 7(4):430-453. Reid, G. K., A. Inglis & H. D. Hoese. 1956. Summer foods of some fish species in Fast Bay, Texas. Southwest, Nat. I(3):i0()-104. Simmons, E, G. 1957. An ecological survey of the Upper Laguna Food or the Red Drum 135 Matlre of Texas. Publ. Inst. Mar. Sci\, Univ. Tex. 4(2): 156— 200. & J. P. Breuer. 1962. A study of red fish, Sciaanops ocellata Linnaeus and black drum, Po^onias cromis Linnaeus. Pnbl. Inst. Mar. ScL, Univ. Tex. 8:184-211. Springer, V. G. & K. D. Woodburn. 1960. An ecological study of fishes of the Tampa Bay area. F!a. Dep. Nat. Resour. Mar. Res. Lab., Prof. Pap. Ser. No. 1. 104 pp. Williams, A. B. 1974. The swimming crabs of the genus Callinectes (Decapoda:Portunidae). Fish. Bull., U.S. 72(3):6S5-798. Yokel, B. J. 1966. A contribution to the biology and distribution of the red drum, Sciaenops ocellata. Master’s thesis, Univ. Miami. 161 pp. Gulf Research Reports Volume 6 | Issue 2 January 1978 Amphilochidae (Crustacea: Amphipoda) from the Western Gulf of Mexico and Caribbean Sea L.D. McKinney Texas A&M University, Galveston DOI: 10.18785/grr.0602.04 Follow this and additional works at: http:/ / aquila.usm.edu/ gcr Part of the Marine Biology Commons Recommended Citation McKinney, L. 1978. Amphilochidae (Crustacea; Amphipoda) from the Western Gulf of Mexico and Caribbean Sea. Gulf Research Reports 6 (2): 137-143. Retrieved from http://aquila.usm.edu/gcr /vol6/iss2/4 This Article is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf and Caribbean Research by an authorized editor ofThe Aquila Digital Community. For more information, please contact Joshua.Cromwell^usm.edu. Gulf Research Reports, Vol. 6, No. 2, 137-143, 1978 AMPHILOCHIDAE (CRUSTACEA: AMPHIPODA) FROM THE WESTERN GULF OF MEXICO AND CARIBBEAN SEA L. D. MCKINNEY Texas A&M University, Moody Marine Laboratory, Ft. Crockett, Galveston, Texas 77550 ABSTRACT Two new species oi Amphitochus, Amphilochus casahoya and Amphilochus delacaya, and one new species of Gitanopsis, Gitanopsis laguna, are described. Relationships within these genera, particularly Amphilochus, are difficult to determine. The new species, however, are similar to some eastern Pacific forms. One known species, Amphilochus neapolitanus is also reported as occurring in both the Gulf and Caribbean. INTRODUCTION The Amphilochidae arc a group of ubiquitous amphipods which are often overlooked because of their small size (2-4 mm). Only one species, Gitanopsis tonugae Shoe- maker, 1933, has been reported from the Gulf of Mexico (Shoemaker 1933). J.L. Barnard (1969)eiToneousiy reported Cyclotelsnn purpureum Potts, 1915, from the Gulf of Mexico. C purpureum was described by Potts (1915) from the Torres Straits near Murray Island in the Coral Sea. ILLUSTRATIONS Figures follow the format established by J. L. Barnard (1970). Capital letters on the figures designate a specific structure. Lower case letters preceding tire capital letter identifies a specific individual. Lower case letters or numbers following the capital letter modifies the description of the part: B = labrum (upper lip); C = coxa; G = labium (lower lip); H = head; L = palp; M = mandible; N = gnathopod; 0 - outer plate or outer ramus; P = pereopod; Q = mandibular molar; S = maxilliped; T = telson; U = ufopod; X = maxilla; Z = mandibular incisor; a = anterior; b = without; h = holotype; 1 = left; r = right; w - palm; x = medial; and y = article. Amphilochidae Diagnosis. Accessory flagellum absent; coxa 1 reduced, partly hidden by a following coxa. Amphilochus Bate, 1862 Diagnosis. Mandibular molar small, nontriturative or with few ridges; gnathopod 2 large, subchelate. Key to Amphilochus la. Mandible nontriturative but armed with a spine; anterior edge of article 6, gnathopod 2 without submarginal spines A. neapolitanus Manuscript received Septembers, I978;acceptcd November 13,1 978. Ib. Mandible reduced but with ridges, gnathopod 2, article 6 anterior edge with 1-4 submarginal spines 2 2a. Gnathopod 2, article 6 with 1-2 submarginal spines Amphilochus casahoya 2b. Gnathopod 2, article 6 with 4 marginal spines Amphilochus delacaya Amphilochus neapolitanus Della Valle, 1893 Stehbing 1906: 150; Chevieaux and Page 1925: 112-113, figs. 106-108; J. L. Barnard 1962:126, fig. 3 Diagnosis. Eyes small, round to slightly oval; antenna 1 reaching beyond antenna 2; mandible nontriturative with a single spine; outer face of gnathopod 2, article 6 without submarginal spines. Material. Texas stations: NT:NMFS-106A, 29°30'N 95‘'0'W; NT!NMFS-I3A, 29°0'N 95°30'W. Other material was taken at Ascension Bay, Mexico, and Nicchehabin reef, Allen Point, and Santa Maria point on Cozumel Island, Mexico. Distribution. Circumtropical and warm-temperate. Amphilochus casahoya, new specie.^ (Figures 1 and 2) Description. Female 3.15 mm. Head and body normal for genus, eyes circular with black center bordered with numerous opaque ommatidia. Antenna 1: Article 2 of peduncle 1.3 times as long as article I, and 3 times as long as article 3; flagellum with 8 articles, distoventral corner of each article with 1-2 elongate, flattened setae; accessory flagellum uniarticulate, subequal in length to first article of nagellum. Antenna 2: Article 5 of peduncle 1.3 times as long as article 4, articles 4 and 5 with distal spines, article 5 with medial row of 4 short spines; flagellum with 1 1 articles. Upper lip: Normal for genus. Mandible: Molar conical, right molar with 3 elongate spinelike ridges, left similar to right but lacking any oversized ridges; accessory blades 11-12; incisor produced forward and medially, distal part V-shaped, toothed, palp with 3 articles of length ratios 12:46:57, otherwise normal for genus. Maxilla 2: Inner plate with medial row of submarginal spines; outer plate longer than inner, with 4 terminal spines. Maxilliped: Article 3 of palp 137 138 McKinney Figure X. Amphilochus casahoya, n. sp., female 3.15 mm. produced medially, with a number of complex spines and 4 short, rounded teeth, otherwise normal for genus. Gnatho- pod 1 : Coxa subovai, partly hidden by following coxa; article 2 elongate; article 4 with I medial spin on posterior margin and 6 distal spines; article 5 with spinose posterior lobe; article 6 with 1 anterodistal, 2 mediofacial spines and serrate, transverse palm lined with 6 slender spines and defined by 2 stout spines; inner margin of dactyl serrate. Gnathopod 2: Article 4 with stout rnediomarginal and 2 distal spines; article 5 with elongate posterior lobe reaching edge of palm, outer margin of lobe with 3 basal spines, distal part spinose; article 6 distally expanded with 1-2 sub- marginal spines on outer face, palm transverse, serrate, lined with slender spines, corner defined by 2 stout spines; inner margin of dactyl serrate, distally attenuate. Pereopod 3: Coxa longer than wide; articles poorly spinose; anterior mar- gin of article 4 with 2 spines, posterodistal corner with 1 ; article 5 willi 1 spine on either margin, distally spinose; article 6 with 3 anteromarginal and 4 posteroniarginal spines; dactyl attenuate. Pereopod 4: Coxa large, quadrate, posterior margin excavate; margins of articles with short spines; posterior spine formula of article 6— 2,2,2,l ;anterior margin of article 6 with 3 spines; dactyl attenuate. Pereo- pod 5: Coxa with rounded posterior lobe; article 2 expanded; articles spinose; anterior spine formula of article 6—2, 2, 2,1 ; dactyl attenuate. Pereopod 6; Coxa like 5 but smaller; longer than preceding pereopods; anterior spine formula of article 6— 1,2, 2,2,1 ; posterior margin with 4 spines; dactyl attenuate. Pereopod 7: Coxa subquadrate; pereopod other- wise like pereopod 6. Epimera: Ventral margin ofepimeron 1 with 3 spines.epimeron 2 with 6 ventral spines and epimeron 3 with 5 ventral spines; posterior margins unproduced. Uro- pod 1 : Peduncle elongate, inner margin with 3 slender spines, outer margin with 5 short spines; inner ramus with 4 inner marginal spines; ramal spines inserted in incisions on margins. UropocJ 2 : Peduncle with 1 distal spine on inner margin and 4 outer marginal spines;inner ramus with 3 inner marginal and 4 outer marginal spines and setulose basal margins; outer ramus 0.6 times as long as inner; inner margin setulose, outer margin with 2 stout, slightly hooked spines and 1 normal distal spine, tip somewhat attenuate; uropod shorter than either 1 or 3. Uropod 3; Peduncle longer than uropod 2; outer margin with 5 spines; rami lanceolate, inner margin of inner ramus with 4 spines and outer margin with 1 spine; outer margin of outer ramus with 4 spines; opposing margins of rami setulose. Telson: normal for genus. Male, unknown. Type. Holotype, USNM 170756, female 3.15 mm; paratype female 2,96 mm, USNM 170757. Type-locality. 7.5 fm reef, Texas, 26°50'N 95'’40'W. 140 McKinney Material examined. Specimens from tlie lype-locality and the jetty complex at Port Isabel, Texas. Size range; 2-3.5 mm. Distribution, Culf of Mexico, offshore waters from intertidal to 15 m. Relationships. Amphilochus casahoya is most closely related Xo Amphilochus delacaya, n. sp., which is also des- cribed in this paper. Amphilochus casahoya differs chiefly in having only 1-2 submarginal spines on article 6 of gnalho- pod 2 rather than 4 as in A. debcaya. IJropods of A. casahoya are less spinous than in^. delacaya. This species appears very close to the Hawaiian species, A. likelike J. L. Barnard, 1970 and A, menehune J. L. Barnard, 1970, These two species as well as .4. casahoya are also similar to Gitanopsis vilordes J. L. Barnard, 1962, in many aspects, except in the structure of the mandible. Relationships among the ampbilochiids are, in general, poorly known. They are a difficult group with which to work as they require extensive dissection for even geneiic determinations. The lack of detailed descriptions and figures of known species also makes it difficult to demon- strate relationships among the members of this genus. Ecological information. This species was taken from a Serpulid reef (known as 7.5 fm reef) some 20 km off the south Texas coast and the intertidal margins of rock jetties of Port Isabel, Texas. Amphilochus delacaya, new species (Figure 2) Diagnosis. Female 2.55. Like A. casahoya in all but the following: Outer margin of article 6 on gnathopud 2 with 4 submar- ginal spines; Peduncle of uropod 1 with 5 slender inner marginal and 10 stout outer marginal spines; inner ramus of uropod 1 with 5 spines on both inner and outer margins; subequal outer ramus with inner margin basally sctulose and 3 distal spines, outer margin with 8 stout cui'ved spines; inner ramus of uropod 2 armed with 4 inner marginal and 5 outer marginal spines, outer ramus with 4 outer marginal spines. Types. Holotype, USNM 170754, female 2.55 mm.; paratype scries of 4 specimens, USNM 170755. Type-'locality. Isla de Lobos Reef, Vera Cruz, Mexico. Material examined. Tlie types plus other specimens from the type-locality. Distribution. Gulf of Mexico, Mexican coast, 5 m depth. Relationships, Most closely related to Amphilochus casahoya; refer to discussion under that species. Ecological information. This species was found only on coral reefs in the groove and buttress zones. Giianopsis Sars, 1895 Diagnosis. Mandibular molar large, triturative, gnatho- pod 2 small, subchelate. Giianopsis laguna, new species (Figures 3 and 4) Description. Female, 2.37 mm. Head and body normal for genus, eyes round. Antenna 1; Length ratio of peduncle articlesl,2,3— 20:23: 1 4; flagellum with 6 articles. Antenna 2: Articles 4 and 5 subequal in length; Flagellum with 5 articles; antenna 2, 0.8 times the length of antenna 1. Upper lip; Bilobed, longer than wide. Mandible: Molar produced, triturative, upper margin with elongate spines; 8 accessory blades on right and 9 on left mandible, blades increasing in width distally;lefl incisor typical, upper edge folded over and inward in an inverted “V’'; right incisor normal and toothed; palp with 3 articles of length ratios 24:43:58, article 3 lanceolate, ventral margin spiculale. Lower lip; Inner lobe.s obsolescent, outer lobes with nearly vertical mandibular lobes. Maxilla 1 : Inner plate rounded, with 1 terminal spine; outer with oblique distal edge and simple terminal spine teeth; palp biarticulaie, distal article 2 time.s as long as basal with 3 chisel-shaped and 1 normal spines. Maxilla 2: Inner plate with 2 terminal and 1 mediomarginal spines, heavily setose; outer plate longer than inner, distally narrow with 3 terminal spines. Maxilliped: Inner plate with 2 distal facial spines and 2 terminal “pits”; outer plate with serrate inner margin and 1 terminal chisel spine; palp with 4 articles, inner margin of article 2 produced medially, spinose; palp and plates normal for genus. Gnathopod 1; Coxa suboval; article 2 elongate with 3 anteromarginal spines; article 4 with 2 posterodistal spines; article 5 with spino.se posterior lobe reaching along half of hind margin on article 6; palm transverse, corner defined by 2 stout spines; inner margin of dactyl serrulate proximally. Gnatho- pod 2: Coxa subquadrate; posterior margin of aiticle 4 with 2-3 stout spines, distal edge with 1 long spine; article 5 with elongate posterior lobe reaching 90% as long as hind margin on article 6*. article 6 distally expanded, anterior edge of outer face with 1-2 submarginal spines, otherwise unarmed; palm transverse with a row of minute spines, corner defined by 2 stout spines; dactyl attenuate, inner margin serrate on upper half. Pereopod 3: Coxa quadrate, longer than wide; anterodistal corner produced, margin with 4 spines; length ratios of articles 4,5,6 -31:35:56, poorly spinose; dactyl attenuate. Pereupod 4: Coxa much larger than preceding coxa, posterior margin excavate; otherwise like pereopod 3, Pereopod 5; Coxa wider than long, bifid, article 2 expanded, with 4 anteromarginal spines; article 3 with 2 anteromarginal spines; article 4 with sharp posterior lobe and 3 spines on either margin; article 5 with 2 single and i pair of anteromarginal spines; article 6 with anteromarginal spine formula of 1 ,2,2,1 ; length ratios of articles 4,5,6-40.40:57, dactyl attenuate. Pereopod 6: Coxa wider than long, with expanded posterioi lobe; article 2 expanded with 5 anteromarginal spines; article 3 with 1 anteromarginal spine; article 4 with sharp posterior lobe, either margin with 3 spines; article 5 with a single and 1 pair of anteromarginal spines and distal cluster of spines on either margin; article 6 with anteromarginal spine formula Gulf-Caribbean Amphilochiids 143 of 1,2,J,2,1; length ratios of articles 4,5,6-49:46:66, dactyl attenuate. Pereopod 7; Coxa like preceding one but reduced; pereopod longer than preceding one, otherwise similar. Epimera: Corners of plates unproduced, ventral margins of plates 2 and 3 with 2 spines each, Uropod 1: Peduncle longer than either 2 or 3, outer margin with 5 spines, inner with I distal spine; rami lanceolate, outer slightly shorter, with 3 outer and 1 inner marginal spines on distal partof ramu.s;inner ramus with 4 inner and 3 outer marginal spines; opposing margins of rami setulose . Uropod 2: Peduncle shorter than peduncles of uropods I or 3, armed with 4 outer marginal spines; outer ramus 0.6 times as long as the inner, with 3 outer and 1 inner marginal spines; inner ramus with 3 inner marginal and 2 outer marginal spines; opposing margins of rami setulose. Uropod 3: Peduncle elongate, unarmed; outer ramus slightly shorter than inner, outer margin with 3 spines; inner ramus with 2 spines on medial parts of either margin; opposing margins or rami setulose. Telson: longer than wide, tapering, apex rounded. Male, unknown. Types. Holotype, USNM 170758, female 2.37 mm; paratypes, 10 individuals, USNM 170759. Type— locality. Holotype from West Bay, Galveston, Texas, 0.5 m depth. Paratype series from Laguna Madre, Texas, 1-2 m depth. Material examined. Tire types and specimens from the following locations; Corpus Christi Bay, Texas; San Antonio Bay, Texas; Southern Laguna Madre near La Pesca, Mexico; and Laguna de Tamiaha near Cucharos, Mexico. Distribution. Gulf of Mexico, bays and lagoons; shallow depths. Relationships. Gitanopsis laguna is most closely related to two species; G. vilorcies J. L. Barnard, 1962, from the California coast, and G. tortugae Shoemaker, 1933, from Tortugas, Florida. differs from G. tortugae in having a more rounded first coxa and a less rounded second coxa. G. tortugae also lacks the submarginal facial spines found on article 6 of gnathopod 2. Gitanopsis laguna differs from G. vilordes in having a more spinose lobe on article 5 of gnathopod 2 and in lacking the stout postero- distal spine on article 2 of that gnathopod. The eyes are more rounded in Gitanopsis laguna and the telson is shorter than in G. vilordes. Ecological information. This species was found in shallow depths, 0.5 m, generally associated with algae. It appears to be restricted to higher salinity hays and lagoons as it was not found in offshore samples. ACKNOWLEDGMENTS The author wishes to thank Dr. J. L. Barnard, U.S. National Museum, for the loan of Caribbean material from the 1960 Smilhsonian-Bredin Expedition; Dr. Wayne Price, University of Tampa, Florida, and Dr. Wes Tunnel, Texas A&l University, for additional material. REFERENCES CITED Barnard, J. f.. 1962. Benthic marine Aiuphipoda of southern California: Families Amphilochidae, Leucothoidac, Stenothoidae, Argissidae, Hyalidac.Poc, Nat. 3:116 163. 1969. The families and genera of marine gammaxidean Ampbipoda. U.S. Natl.Mus. Bull. 271:l-.‘>35. 1970. Sublittoral Gammaridea (Amphipoda) of the Hawaiian Islands. Smithson. Contrib. Zool, 34:1-286. Potts, F. A. 1915. The fauna a.ssociated with the crinoids of a tropical reef: with especial relcrences to its colour variations. Pap. Dep. Mar. Biol Carnegie fnsi. Wash. 8:71-96. Shoemaker, C. R. 1933. Two new genera and .six new .species of Amphipoda from Tortugas. Papers from Tortugas Laboratory. 28(15). {Carnegie Inst. Wash. Puhl. 435:245-256.) Gulf Research Reports Volume 6 | Issue 2 1978 Food of the Atlantic Croaker, Micropogonias undulatus, from Mississippi Sound and the Gulf of Mexico Robin M. Overstreet Gulf Coast Research Laboratory Richard W Heard Gulf Coast Research Laboratory DOI: 10.18785/grr.0602.05 Follow this and additional works at: http:/ / aquila.usm.edu/ gcr Part of the Marine Biology Commons Recommended Citation Overstreet, R. M. and R. W. Heard. 1978. Food of the Atlantic Croaker, Micropogonias undulatus, from Mississippi Sound and the Gulf ofMexico. Gulf Research Reports 6 (2): 145-152. Retrieved from http:// aquila.usm.edu/gcr /vol6/iss2/5 This Article is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf and Caribbean Research by an authorized editor ofThe Aquila Digital Community. For more information, please contact Joshua.Cromwell^usm.edu. Gulf Research Reports, Vol. 6, No. 2, 145-152, 1978 FOOD OF THE ATLANTIC CROAKER. MICROPOGONI AS UNDULATVS, FROM MISSISSIPPI SOUND AND THE GULF OF MEXICO' ROBIN M. OVERSTREET AND RICHARD W. HEARD Parasitolog)’ Section, Gulf Coast Research Laboratory, Ocean Springs, Mississippi 39564 ABSTRACT The diet of the Atlantic croaker from Mississippi Sound has been examined for the first time. Over 83 taxa were encountered, or more than were reported from croaker in any other region. We also found 60 taxa, 36 of which over- lapped with the above, in croaker from various offshore stations in the Gulf of Mexico. In Mississippi Sound the frequency of occurrence of items revealed primarily crustaceans followed by polychactes, molluscs, fishes, and less common items, and, in the open Gulf, molluscs appeared slightly more often than in inshore croaker and than polychaeies in offshore fish. The diets were assessed according to length offish, season, depth of water, and locality. INTRODUCTION In this study we examined the stomach and intestinal contents of many variously collected specimens of the Atlantic cxoTAti. Micropogonias undulatus, a sciaenid, from Mississippi Sound and from adjacent water of the Gulf of Mexico. If presents specific identifications for numerous items and compares them, usually by taxonomic groupings, according to length of fish, season, depth of water, and geographic location. The Atlantic croaker has an inferior mouth, sensory bar- bels, and coarse-straining gill rakers, all adaptations useful for feeding in and on the substratum. Chao and Musick (1977) have compared some of these features in several sciaenids and related them to feeding. The croaker usually comprises the most prevalent component of the industrial ground fish fishery in the Gulf of Mexico (Gutherz 1977) and is becoming increasingly important as a commercial foodfish (Gutherz et al. 1975). Moreover, it has always been an im- portant component of the catch of sports fishermen in Mississippi who fish from banks and bridges and has long been recognized as a very abundant fish in the northern Gulf (e.g., Gunter 1938). Mississippi Sound acts as a rich nursery region for juvenile croaker. Its salinities fluctuate from 0 to 37 parts per thousand (ppt), usually between 6 and 15 ppt (Christmas and Eleuterius 1973), and food for croaker and other inhabitants is typically plentiful. Soon after adult croaker spawn offshore, young fish up to 2 cm standard length (SL) begin occupying estuarine regions nearshore. This period extends from about October to February. About May, June, or July , a large proportion of that stock, then up to about 9 or 10 cm long, leaves for offshore Gulf water. Nevertheless, enough 2- and 3-year-old croaker remain in the Sound to support a sports fishery. 'This study wa.s eonducteU in cooperation with the U. S. Depart- ment of Commerce, NOAA, National Marine Fisheries Service, under PL 88-309, Project Nos. 2 262-Rand 2-325-R. Manuscript received October 10, 1978; accepted October 23, 1978. MATERIALS AND METHODS Croaker were collected by a variety of means for differ- ent purposes. From Mississippi Sound, a total of 221 commercial-size fish between June 1976 and October 1977 were seasonally trawled, gill-netted, or hooked and immedi- ately placed on ice for the primary purpose of removing and assessing the food contents. We trawled many other croaker from Mississippi Sound during 1970-1972 and 1975-1977 and maintained them alive for up to 2 days so that they could be critically examined for parasites. As for food contents, however, only the first few fish from each collection had nondigested items. Still, that material pro- vided most of the data on croaker less than 7 cm SL (all measurements in this paper are standard lengths) plus a few from larger fish. Fishes from the Gulf of Mexico were col- lected from the R/V OREGON II and GEORGE M.BOWERS by members of the National Marine Fisheries Service (NMFS) between June 1974 and October 1977. Over 1,000 offshore fish came from many stations ranging from off Mobile Bay, Alabama, to off Galveston, Texas, from near shore in 1 1 meters depth to farther offshore at 90 meters. These fish were immediately frozen upon capture so that food contents and specific parasites could be preserved. Most had no food items when examined. Possibly as many as a half had their stomachs partially or entirely protruded by the rapid pressure difference when raised from rela- tively deep to surface water; consequently, they regurgitated their food. Once removed from the measured fish, food contents were placed in 10% formalin for later identification. Because the nature of the study was not to deal with energy conver- sion and because the different fish had all possessed their food for different periods of time, no attempt was made to assess the volume or weight of food material. RESULTS Prevalence of recently fed Atlantic croaker with various dietary items appears as general, moderately general, and specific categories (Tables 1 , 2, and 3). A large percentage (44%) of sampled croaker from Mississippi Sound had 145 146 Overstreet and Heard TABLE I. Percentage of Atlantic croaker of moderate and large sizes from inshore (I) and offshore (O) habitats containing various food items according to general category. Fisli Length in mni SL 95-198 76-195 200-350 200-351 Total I O I O I O No. Exam. 131 1169 119 137 250 1306 No. w/Food 117 144 108 42 225 186 Food Item Occurrence (%) Annelida 44.4 38.2 43.5 11.9 44.0 32.3 Mollusca 22.2 33.3 44.4 52.4 32.9 37.6 Crustacea 82.9 48.6 68.5 71.4 76.0 53.8 Fishes Other 17.9 0.7 28.7 14.3 23.1 3.8 animals 4.3 1.4 13.9 7.1 8.9 2.7 Plants 15.4 6.5 7.1 11.1 1.6 Detritus 22.2 1.4 15.7 9.5 19.1 3.2 TABLE 2. Prevalence of feeding Atlantic croaker from Mississippi Sound with various stomach contents in relationship to season according to moderately general category. Season No. E.xamined No. with Food Food Item Spring 62 52 Summer 100 87 Fall 56 54 Winter 32 32 Total 250 225 Occurrence (%) Hydrozoa 1.1 0.4 Annelida 48.1 50.6 37.0 31.3 44.0 Gastropoda 7.7 9.4 3.1 Scaphopoda 1.9 0.4 Pelecypoda 28.9 31.0 20.4 56.3 31.5 Cephalopoda 1.9 0.4 Ectoprocta 2.3 0.9 Echinoderma 3.9 3.1 1.3 Osiracoda 1.9 4.6 2.2 Cirripeda 1.9 0.4 Copepoda 3.9 12.5 2.7 Slomatopoda 15.4 3.7 3.1 4.9 Mysidacca 9.6 20.7 5.6 12.5 13.3 Arnphipody 28.9 50.6 9.3 3.1 28.9 Isopoda 3.9 11.5 5.3 Penaeidae 21.2 41.4 16.7 40.6 20.7 Palaemonidae 1.9 9.2 4.0 Callinectes 7.7 14.9 3,7 3.1 8.9 Other Decapoda 51.9 28.7 8.8 25.8 Other Crustacea 13.5 3.7 31.3 8.4 Insecta 3.9 9.2 1.9 4.9 Other luvertebrata 3.9 1.1 6.3 2.2 Ostcicluhyes 26.9 16.1 29.6 25.0 23.1 Algae 15.4 14.9 1.9 9.8 Vascular plants 3.1 0.4 Deliitus 11.5 28.7 22.2 6.3 20.0 receiUly eaten annelids (Table 1). 01" these, 79% shorter than 200 mm ate Nereis SHCemea; fewer large ones did (13%). Considering all the annelids together, possibly all poly* chaetes, little difference occurred between the percentage of relatively large and small fish feeding on them. Other primary dietary items consisted of pelecypods, amphipods, fishes, and penaeid shrimps (Table 2). Mufinia lateralis was the most prevalent pelecypod (in 28% of the 32% of croaker with bivalves), and both Corophium louisiamim and Ampelisca abciita were commonly encountered amphipods (45 and 29% of the 29% of croaker with amphipods, respectively). Actually, the broad crustacean assemblage constituted the primary dietary group, being in 76% of the fed croaker. Mysids and blue crabs were common, in 13 and 9% of the fish, but less so than amphipods and shrimps. Most fish in the croaker stomachs had been digested beyond a stage necessary for identification. Croaker-length, as already indicated, had some, bearing on items consumed. Small croaker (95 to 198 mm) had more crustaceans than larger ones (83 versus 69%, respectively); whereas, an opposing relationship between item and croaker- length for both molluscs and fishes occurred: in 22 opposed to 44% and in 18 opposed to 29% of the croaker, respec- tively. When considering the crustaceans, we note (he dif- ference in abundance appears to reflect mostly amphipods and mysids which were found in 44 and 12% and in 19 and 7% of the large and small Rsh, respectively; the amphipod Corophium louisianum occurred in 21 and 4%, involving a total of 45% of the croaker with amphipods, and the mysid Myskiopsis almyra was in 16 and 4% of large and small fish, involving 77% of those fish with mysids. Seasonality has an obvious influence on diet. Table 2 shows that the presence of amphipods, algae, portunid crabs, isopods, and miscellaneous crustaceans are most prominent during spring arid summer and much less conspic- uous during fall and winter. For example, amphipods occurred in 29 and 51% of the croaker in spring and sum- mer, respectively, opposed to 9 and 3% in fall and winter. Other food items occurred more frequently during other seasons, such as penaeid shrimps in summer and winter. Separate collections of smaller fish from the same locality provided comparative data on fish less than 70 mm long. Fish less than 25 mm fed on amphipods, ostracods, and copepods including unidentified harpucticoids, Acartia tonsa, Pseiidndiaplomm corona tus, Temora turhimta, and others. Of 36 recently fed croaker 25 to 74 mm long, 25 contained copepods exclusively .Others contained Palaemorh ctes plight mysids, other shrimps, amphipods, fisli remains, the spionid polychaete Paraphonospio pinnata, or a com- bination of items usually includitig copepods. Atlantic croakci caught offshore demonstrated a differ- ent diet in many respects than croaker from Mississippi Sound. Jn two cases these results are listed in the same tables as data for inshore samples (Tables 1 and 3). The Food of the Atlantic Croaker 147 TABLE 3. Prevalence of feeding Atlantic croaker from Mississippi Sound and from combined offshore Gulf of Mexico stations containing various food items. Mississippi Sound Gulf of Mexico (Fish Length in mm SL) (Depth in Meters) 95-198 200-350 Total <30 >30 Total Number Fish Examined 131 119 250 77 111 188 Number Fish with Food 117 108 225 77 109 186 Food Item Occurrence (%) Hydrozoan 0.9 0.4 1.3 0.5 Platyhelminth Stylocus ellipticus 0.9 0.4 Nemertean 1.9 0.9 Polychaetes Capilallid or oligochactc 2.6 1.3 Diopatra cuprea 0.9 1.9 1.3 2.6 1.1 Drilonereis sp. 1.3 0.5 Glycera amt'ricana 0.9 4.6 2.7 Glycinde sp. 4.3 2.2 1.3 0.5 Goniada sp. 0.9 0.4 Hypaniola florida 1.7 0.9 1.3 Nereis sp. 1.9 0.9 2.6 1.1 Nereis suecima 35.0 5.6 20.9 Paraprionspio pinnata 0.9 0.4 Pectinana gouldii 0.9 0.4 Unidentified polychaetes 7.7 33.3 20.4 49.4 18.3 31.2 Unidentified tcrebellid 2.6 1.1 Gastropods Acieocina canaliculata 0.9 0.4 Amchis sp. 0.9 0.4 2.6 1.1 Nassarius acufus 0.9 0.5 Natica canrem 1.8 1.1 Neritina re diva t a 0.9 0.5 Retusa sp. 0.9 0.4 Sinum perspectivuni 2.6 1.1 Unidentified gastropod 4.6 2.2 2.6 1.1 Scaphopod Dentalium sp. 3.7 2.2 Pelecypods /) my^dalurn papyrium 7.7 4.0 Anadara transversa 1.3 0.5 Corbiculid remains 1.3 0.5 Corbula sp. 0.9 0.4 0.9 0.5 Ensis minor 0.9 0.9 0.9 Ischadium rccurvum 4.3 2.2 Maconia mitchdli 0.9 0.9 0.9 Mulinia lateralis 9.4 8.3 8.9 12.9 5.4 Mydlopsis leucophaeuta 0.9 0.4 Nucukixa conccntrica 0.9 20.3 10.2 10.4 22.9 17.8 Tagetus pleheius 1.9 0.9 1.3 Tellina sp. 1.7 1.9 1.8 Varicorbula operculala 0.9 0.5 Unidentified bivalve remains 0.9 10.2 5.3 1.3 1.8 1.6 Cephalopod Octopus sp. 0.9 0.4 Ostiacod 0.9 0.4 1.8 1.1 Cirripeds Balanus improvisus 3.4 1.8 Unidentified barnacle 0.9 0.4 148 Overstreet and Heard TABLE 3 (Continued). Prevalence of feeding Atlantic croaker from Mississippi Sound and from combined offshore Gulf of Mexico stations containing various food items. Mississippi Sound Gulf of Mexico (Fish Length in mm SL) (Depth in Meters) 95-198 200-350 Total <30 ^30 Total Number Fish Examined 131 119 250 77 111 188 Number Fish with Food 117 108 225 77 109 186 Food Item Occurrence (%) Elopepods Calanoid 0.9 3.7 2.2 Unidentified copcpod 0.9 0.4 1.8 1.1 Stomatopods Squilla diceptrix 1.3 0.5 Squilla edentata 0.9 0.4 Squilla cmpusa 0.9 3.7 2.2 5.2 2.2 Squilla remains 0.9 4.6 2.7 1.3 11.9 7.5 Mysid Mysidopsis almyra 20.5 6.5 13.8 Cumacean 6.5 3.1 0.9 0.5 Amphipods Ampelisca ahdita 14.5 1.9 8.4 Ampelisca sp. 3.4 3.7 3.6 0.9 0.5 Cerapus sp. 11.9 4.6 8.4 Corophium louisianum 21.4 3,7 12.8 Gammarus mucromtus 5.1 2.7 Gamfrtorus tigrinus 1.7 0.9 Hausiorid 0.9 0.4 Mehta nitida 2.6 1.3 Unidentified amphipod 0.9 2.8 1.8 Tanaidacean Leptocheta sp. 9.3 4.4 0.9 0.5 Isopods Cassidinidea lunifrom 0.9 0.4 Cyathura polita 2.6 5.6 4.0 Edotea montosa 0.9 0.4 Isopod remains 0.9 0.4 Penaeids Parapenaeus longirostris 0.9 0.4 1,8 1.1 Pemeus aztecus 3.4 5.6 4.4 Pcnaeus remains 30.8 21.3 26.2 3.9 8.3 6.5 Penaeus setifcrus 1.7 0.9 1.3 Sicyonia dorsalis 1.8 1.1 Ttachypemeus sp. 1.3 0.5 Sergestid Acetes americanus 2.6 4,6 3.8 Cartdeans Alpheus floridanus 9.3 4.4 8.3 4.8 Alpheus sp. 1.3 0.9 1.1 Ogyrides Umicola 1.7 0.9 1.3 0.9 1.1 Palaemonetes pugio 5.9 1.9 4.0 Symlpheus townsendi 0.9 0.4 1.3 0.5 Unidentified caridean 2.8 1.3 1.3 3.7 2.7 Anomurans Albunea gibbesi 0.9 0.4 3.9 0.9 2.2 Callianassa jamaceae 1.7 2.8 2.2 Callianassa remains 0.9 0.4 0.9 1.1 Pagurus spp. 0.9 0,4 2.6 21.1 13.4 Food of the Atlantic Croaker 149 TABLE 3 (Continued). Prevalence of feeding Atlantic croaker from Mississippi Sound and from combined offsliore Gulf of Mexico stations containing various food items. Number Fish Examuied Number Fish with Food Food Item Mississippi Sound (Fish Length in mm SI.) Gulf of Mexico (Depth in Meters) 95-198 131 117 200-350 119 108 Total 250 225 <30 77 77 '^30 111 109 Total 188 186 Occurrence (%) Brachyurans Ca lappa sp. 0.9 0.5 CalUnectes remains 2.8 1.3 Callinectes sapidus 11.1 4.6 8.0 2.6 1.1 CalUnectes similis 1.9 0.9 Chasmocorcinus mississippiensis 0.9 0.5 Eurypanopeus depressus 1.7 0.9 Euryplax nitida 6.5 3.2 Hepaius epheliticus 1.3 0.5 Hexapanopeus angustifrons 0.9 0.4 0.9 0.5 Leiolambrus ndidus 1.9 0.9 1.3 0.9 1.1 Pinnixa sp. 0.9 0.5 Ponunus gihbesi 1.3 0.5 Poriunus spp. 3.7 1.8 4.6 2.7 Raninoides louisianensis 2.8 1.6 Rhithropanopeus harrisi 17.1 2.8 10.2 Solenolambrus sp. 0.9 0.5 Unidentified hianchyuran larva 0.9 0.4 Unidentified goneplacids 0.9 0.4 6.5 13.8 10.7 Unidentified xanthid 5.1 4.6 4.9 1.3 0.5 Unidentifiable decapod remains 2.8 1.3 Insect Chironoraid midge larva 6.8 2.8 4.9 Ectoprocts Bowerhankia gracilis 0.9 0.4 Membranipora arborescens 0.9 0.9 0.9 Chaetogiiatli 1.3 0.5 Echinoderms Echinoid remains 2.8 1.3 0.9 0.5 HemiphoUs elongaia 3.9 0.9 2.2 Fishes Anchoa hepsetus 0.9 0.4 Anchoa mi t chilli 1.7 5.6 3.6 2.6 1.1 Anguilliform remains 0.9 0.4 Gohiosoma bosci 2.6 0.9 1.8 Microdesmus longipinms 0.9 0.4 Symphurus plagiusa 0.9 0.4 Unidentifiable fish parts 11.1 24.0 17.3 7.8 1.8 4.3 Unidentifiable goby 0.9 0.9 0.9 Plants Algae and unidentified plant matter 18.8 1.9 10.7 1.3 0.5 Sea grass 0.9 0.4 Detritus and other organic matter 23.1 17.6 20.4 7.8 3.2 offshore croaker feed most commonly on crustaceans (54% of the fish with food), but also on moUuscans and annelids (38 and 32%, respectively). Crustaceans occurred most fre- quently in samples from water deeper than 30 meters (69 versus 33% in water less than 30 m) and from larger fish (7 1 versus 49% in relatively short fish). Actually , crustaceans, the general food most frequently observed to be consumed from both inshore and offshore habitats, had a higher preva- lence in inshore croaker. In fact, of the major general cate- gories, only molluscs occurred in more offsliore croaker, 150 OVERSTREET AND HEARD and then not substantially (Table 1). Offshore molluscs, primarily bivalves, show similar relationships as the offshore crustaceans with water-depth and with fish-length. On the other hand, offshore annelids, primarily polychaetes, occurred most commonly in the slrallower samples (in 52 versus 18% of the fish) and in smaller fish (38 versus 12%). Other less common items such as fishes, plants, and detritus all occurred slightly more frequently in the large croaker from shallower offshore water. Specific animals, as expected, typically occurred most frequently in specific regions. For examples, the bivalve Nuculana concentrica occurred most frequently in deeper water as did the hermit crabs, Fagunis spp. We also point out that more smaller fish had hermit crabs than those fish longer than 20 cm. On the other hand, the stomatopod Squilla empusa occurred in fish only from the shallower localities. DISCUSSION The long list of different food items in the Atlantic croaker constitutes the most important aspect of this study. Differences in dietary organisms taken from insliore tind offshore samples reflect a difference in components of the communities from the two general regions. A more complete delineation of the localities would have emphasized the differences in communities even more. Stomach contents of croaker had not been previously reported from Mississippi waters. Our data reveal some differences among samples according to depth, length of fish, and season, as well as to locality. In addition to mere examination of tables listing and comparing the percentage/ frequency of occurrence for different items, we compared some of the values statistically. For example, using Wil- coxon’s signed rank test (Steel and Torrie 1960:402) we accept the hypothesis that the frequencies of the various food items differ between fish less and greater than 200 rnm in both Mississippi Sound (Tiggser ~ 147.5 and 147. .5 > hla:=.0l, n=24) and the Gulf of Mexico (T^esj^er " and 33 > 23«=.01, n=;17)’. however, the ranks of the frequencies of those items do not significantly differ between inshore and offshore stocks (Tigjjsgr “ and 61.5 < 68 q=. 01, n=25)- Still a Spearman's rank test (Fritz 1 974) suggests that compared ranks in all three comparisons are correlated: Tj. = 0.582, 0.627, and 0.521 with “t” ^ 3.360 > 2.8iya='.01, 22df, 3.116 > 2.947a. 01 , ISdt.and 2.924 > 2.807 cf=. 01, 23df, respectively. A Friedman test (Conover 1971) was used to compare the generalized items by season. In this case, T = 5.06, and 5.06 < 1 1.34ft=,oi,3dfi allowing us to accept the null hypothesis that no difference exists for the croaker’s diet among any of the seaons. This result, however, might be misleading becau.se of the high prevalence of fish in the croaker stomachs during the fall and the low prevalence during the summer. Inspection of the less generalized items in Table 2 shows a lower prevalence in fall than in other seasons for crustaceans, as well as other variations. Parker (1971) used the Spearman’s rank test to compare differences in ranked frequencies between food items from Texas and Louisiana in different croaker-length groups. In order to compare our findings for large fish with his, we joined some less common groups together, deleted the group for mud and sand since we did not always docinnent that category in our material, ranked the values, and com- pared them with the corresponding ones for croaker from Louisiana and Texas. The results of the tests do not indicate that a correlation exists between the paired groups (rs = 0.467 and 0.155 when compared with values from Louisi- ana and Texas, respectively; “t” = 2.243 and 0.667 v/ith those values less than = 2,878). Wlien ranking the least frequent item as I (as suggested by Fritz [1974]) rather than the most frequent one, we obtained rs = 0.465 and 0.138 with ‘‘t” ~ 2.231 and 0.589, indi- cating the same conclusions. Additionally we used Wilcoxon's test and accept the alternative hypothesis that the croaker’s diet in Mississippi Sound differs from that encountered in both Louisiana (T|es^er “ 45.5, 45.5 > 38a=.01, n=20) and Icxas (T|csscr = ^^’ 56 >38). Several analyses of the croaker’s food contents have been conducted. Of these, no reason exists not to believe that the croaker acts opportunistically, feeding on any easily available prey. Some learning behavior may occur because specific individuals from a collection of confined fish occasionally had exclusively fed on specific food items different from those found in their counterparts. This observation was especially conspicuous for small croaker heavily packed with Pseudodiapkvnm coromtus, Cow- phiurn louisianurn, or other small cnislaceans, but it also occurred for larger croaker feeding on large prey. Darnell (1958) noted the same tendency for a few young croaker to specialize on chironomids, inysids, or amphipods. We found that most individuals fed on a variety of items. A large number of authors have reported mostly unident- ified food items from croaker. One paper by Stickiiey et al. (1975). however, presented an extensive list with 58 differ- ent taxa in croaker from Georgia. We found over 83 taxa in Mississippi Sound and 60 in the Gulf including 36 that overlapped between the two regions. Chao and Musick (1977) referenced most of the studies from the Atlantic coast. Those studies from the Gulf of Mexico are by Gunter (1945), Reid (1955), Reid et al. (1956), Darnell (1958). Inglis (1959), AvaulL et al. (1969),Hanson (1969), Fontenot and Rogillio (1970), Parker (1971), Day ct al. (1973), Diener et al. (1974), Weaver and Holloway (1974), Roussel and Kilgen (1975), and Chen (1976). Croaker from different localities feed on the same general items, but often in different proportions and on different specific components. In general, croaker feed on crustaceans, polychaetes, pelccypods, fishes, detritus, and mi.sccllan£c)u.s invertebrates and plants. Several factors obviously dictate the proportions and compositions of these food items, but Food of the Atlantic Croaker 151 these factors have been inadequateJy studied. Reid (1955) found 45% of a sample from East Bay, Texas, fed on molluscs and 1 3% on shrimp. After construction of Rollover Pass, an entrance allowing introduction of water from the Gulf into the Bay, Reid et al. (1956) found a decreased frequency of croaker, and of the sample, 98% fed on molluscs, but still 13% on shrimp. Data from our tables reveal some differences according to length of fish, season, locality, and depth of water. Other papers also revealed differences related to various variables. As an example, Farrell (1970) showed a seasonal variation in amphipod consumption with most ampliipods eaten in spring and early summer in Mississippi Sound, but differing somewhat, by exact locality. Species oi Corophmm predominated. Commercial shrimps and blue crabs constituted a .size- able portion of the diet in croaker from Mississippi and a few, but not all, other Gulf locations. In spite of the high prevalence of penaeids in localities inhabited by the croaker in Georgia and North Carolina, few individual croaker ate these shrimp; rather, they utilized Neomysis americana (Stickney et al. 1975). Stickney and coworkers pointed out that few taxa occurred in large numbers of croaker, citing N. americana in 1 7% of the croaker as the most frequent item the authors encountered. We observed several food items that occurred more often. In croaker from Mississippi Sound, spp, (in most cases, the remains of Penaeus aztecus were not differentiated from those of P. setiferus) occurred in 30% of the fish and the polychaete Nereis snccinea in 21%. Members of neither taxon was common offshore (5% of offshore croaker did contain Penaeus spp.), but hermit crabs in the genus Pagurus occurred in 1 3% of the offshore fish, 21% of those fish from deeper than 30 m, and rarely in croaker from the Sound. The bivalve concentrica was found in 18% of the offshore croaker and 10% of the inshore ones. Primary species comprising each general group differ from habitat to habitat. As an example, we consider clams. Whereas the razor clam constitutes the most common bivalve food item for the croaker along many Atlantic coast local- ities, its role is substituted elsewhere. Rangia cimeata fills this role inLakePontchartrain,Mu/mw/fl^erafoand Nuculana concentrica in Missi.ssippi Sound, and Macoma mitchelli in East Bay, Texas. In regions where more diversified bivalve populations occur such as in the Gulf of Mexico, dominant. forms may be less conspicuous. Nuculana concentrica occurred in many of the croaker wc examined, but large samples from other sites would probably yield other common species. Our offshore samples do not represent a single locality. In fact, fish with food came from 32 different stations over a 3-year period. As indicated earlier, most individuals did not have food present and obtaining food data was a sec- ondary mission. Nevertheless, our data reveal some valuable generalizations about the food of the offshore Gulf croaker. Food contents of croaker also collected by the NMFS during a portion of the same period* but with only two over- lapping stations, were analyzed by Chen (1976). She grouped data from different stations and found contents in 300 croaker 26 to 339 mm SL to have a frequency of occurrence greatest for polychaetes (53%), followed by iialantian deca- pods (47%), mysidaceans (20%), amphipods (12%), brachy- urans (11%), brittle stars (11%), and other less common items. Ninety percent of the croaker had organic or inor- ganic matter, presumably most of which were partially digested items. The primary differences between our findings and those of Chen are that in our samples molluscs occurred more frequently and the diet was much more diversified. We did not encounter a.s many polychaetes and found no mysids or ophiuroids. According to Chen’s graphs separating diet by size of fish, the fish in three unspecified size-groups gener- ally appeared to have similar diets. Comparison of Chen’s and our data, just like comparison of most data from the same or from different area.s, shows that portions of croaker diet may vary significantly among compared samples. The difference probably primarily reflects the availability of the specific items al a specific collecting site. ACKNOWLEDGMENTS We gratefully thank the following people for their help in different aspects of the study: Ronnie Palmer, Roswitha Buxton, Laurie Toomey, Kay Richards, Ann St. Andrie, Thomas Dcardorff, Alan Fusco, Harriet Perry, and Beryl Heard, We also thank members of the Southea.st Fisheries Center of the National Marine Fisheries Service for collecting offshore croaker. Those of whom we are aware are Elmer Gulherz, Bennie Rohr, Perry Thompson, and Nathaniel Sanders, Jr. REFERENCES CITED Avauli, J. W., Jr., C. L. Birdsong & W. G. Perry, Jr. 1969- Growth, survival, food habits and sexual development of cxoakci, Micrn- pogon undulaius, in bracki.sh water ponds. Proc. Southeast. Game Fish Comm. 23:251. Chao, L, N- & J, A, Milsick. 1977. Life history, feeding habits, and functional morphology of juvenile sciaenid fishes in the York River estuary, Virginia. Fish. Bull., U.S. 75(4j:{\2Y\9^~2QA. Brinkmann, A. 1936. Die nordischen Munidaarlen und ihre Rhizoccphalen. Bergens Mus. Skr. 1 8: 1 - 1 1 1 . Brown, F. A., Jr. 1944. Hormones in the Crustacea. Their sources and activities. Quart. Rev. Biol 19:32—46, 118-143. - — 1948. Hormones in Crustaceans, pp. 159-199. In: Pincus, G. and K. V. Thimann (eds.), The Hormones. Vol. 1, Academic Press, New York. Bruntz, L. & J. Gaulrelet. 1902. Etude comparee des liquides organiques de la Sacculinc ct du Crabe. Compt. Rend. Acad. Sc., Paris 134:349-350. Bulgurkov, K. 1938. Study of Rliizocephala and Bopyridac from the Bulgarian Black Sea Coast. Trud. na Chernorskata Biol. Sta. V ’Varna. No. 7:69—81. Butler, T. H. 1955. Re-discovery of the parasitic cirripede Mycetomorpha vancouverensis Potts, in British Colombia waters. J. Parasit. 41:321. Cameron, T. W. M. \9 56. Parasites and Parasitism. Methuen & Co. Ltd. 322 pp. Cantacuz^ne, A. 1925. Reaction du crabe Sacculine vis-a-vis d'une infection experiinentale de la Sacculine. Compt. Rend. Soc. Biol, Paris 93:141 7-1419. CantacuzSne, J. 1913, Observations relatives a certains proprietes du sang de Carcinus maenas parasite par la sacculine. Compt. Rend. Soc. Biol, Paris 74(2): 1 09-11 1 . Carol!, E. 1929. La presenza del genere Thompsonia Koss- mann nel golfo di Napoli. Arch. Zool. Ital 13(3-4): 493-498. 1931. Azione modificatrice dei bopiridi e dei rizocefali sui caratteri sessuali secondarii delle callianasse. Arch. Zool Ital, Torino 16(1 2):3l6-322. Caullerv, M. 1906. Sur un amoebien parasite des embryons de Peltogasicr curvatus Kossm. Compt. Rend. Soc. Biol, Paris, an. 58, v, 61 , v. 2 (28):266— 269. Bibliography of Rhizocephala 159 Caullery, M. 1907a. La castration parasitaire produite sur les rhizocephales par les cryptonisciens. Compt. Rend. Soc. Biol., Pans 62(3):113-116. J907b. Stir les liriopsidae, crustaces isopodes (epicarides), parasites des rhizocephales. Compt. Rend. Acad. Sc„ Paris 144(2): 100 102. 1908. Recherches sur le^ Liriopsidae, epicarides cryptonisciens parasites des rhizocephales. Mitth. Zool. Station Neapel 1 8(4) : 5 83 -643 . Causey, D. 1954. Parasitic barnacles. Educational Focus (Rochester) 25:9-10. Cavolini, F. 1787. Memoria sulla generazione dei pesci e dei granchi. Napoli, in-4°. Cendrero, 0. 1972. Dates sobre el parasitismo de Sacculina carcini en Carcinus maenas de la baliia de San Lauder. Bol. R. Soc. Espanola Hist. Nat, (Biol.) 70:131-136. Charniaux-Colton, II. 1956. De'terminisme hormonal de la differenciatJon sexuelle chez les Crustaces. Ann. Biol. 32:371 399. Chassard'Bouchaud, C. &, M. Hubert. 1975a. Etude ultra- structurale de I’organe Y de Carcinus maenas L.: com- paraison cntre des animaux sains et des animaux parasites par Sacculina carcini Thompson, Compt. Rend. Acad. Sc., Paris 281:893 895. & 1975b. Donnies preliminaires sur I’ultrastructure de To range Y du crabe Carcinus maenas L. sain el parasiti par Sacculina carcini Thompson. J, Micr. et Biol. Cellulaire 23(3 8a). & 1976. On the fine structure of the regressing ecdysial glands of Carcinus maenas L. (Crus- tacea Decapoda) parasitized by Sacculina carcini Tliomp- son. Cell. Tis. Res. 167(3):35 1-361. Chia, V. 1967. Thompsoniu sp., a rhizocephalan from Singapore. Mfl/flvswrt Vet. J. 4(2): 160. Christmas, J. Y, 1969. Parasitic barnacles in Mississippi estuaries with special reference to Loxothylacus texanus Bosch ma in the blue crab { Callinectes sapidus}. Proc. 22nd Ann. Conf. SE Assoc. Game <1 Fish Comm., pp. 272-275. Codreanu, R. 1941. Sur les Pagures du Littoral roumaiii de la Mer Noire et leurs Crustace's parasites. Analele Acad, Rep. Populare Romane, Mem. Sect. Stiintifice (ser. 3) 16:1095-1130. 1960. Sur quelques Pagures littoraux de I’Albanie et la presense du Rhizocephale Septosaccus cuenotti Duboscq 1911 dan I’Adriatique. Rapp. Comm. int. Mer. Medit. 15(2): 127-140. 1961, Crustaces parasites a affinitie^s indo- pacifiques dans la mer Noire. Hydrobiologia, Bucaresti 3:133-146. 1 968. Y a-t-il des especes biologiques (jumelles) chez les e'picarides et les rhizocephales? Trav. Mus. Hist. Nat. **Gr. An/Z/za, "Bucaresti 8(2):60i— 614. & M. Codreanu. 1959. Donnees biologiques et statisliques sur un Pagure, Diogenes pugilator (Roux) de la Mer Noire et ses Crustace's parasites. Essai d’analyse de ses caract'bres sexuels. Lucrarile Sesiunii Stiintifice Agigea 21:315-348. Cornubert, G. 1952. Influence de la sacculine Sacculina carcini Thompson sur le crabe Pachygrapsus marmoratus Fabricius.Cbmph Rend, Acad. Sc., Paris 234(1 1):1218— 1220 . 1953. Effets de I’ablation des pedoncules oculaires sur la fe'minisation de Tabdomen du crabe Pachygrapsus marmoratus Fabricius male parasite"^ par Sacculina carcini Tliompson. Compt. Rend. Acad. Sc., Paris 236(10): 1082-1084. 1954. Influence de Tablation des pedoncules oculaires sur la mue du crabe Pachygrapsus marmoratus Fabricius parasite' par Sacculina carcini Thompson. Bull. Inst. Oceanogr. Monaco 1039:1—4. Courrier, M. R. 1921. Sur le determinisme des caracteres sexuels secondaires chez les Arthropodes. Compt. Rend. Acad. Sc., Paris 173:668-671. Coutiere, H. 1902a. Sur un nouveau type de rhizocephale, parasiti des Alpheidae. Compt. Rend. Soc. Biol, Paris 54(13):447-449. 1902b. Sur un nouveau type de rhizocephale gregaire parasiti des Alpheidae. Compt. Rend. Soc. Biol, Paris, 54(19):625-626. 1902c. Sur un nouveau type de rhizoce'phale grdgaire parasite des Alpheidae. Compt. Rend. Soc. Biol, Paris 54(21):724-725. 1902d- Sur un type nouveau de rhizocephale, parasiti des Alpheidae. Compt. Rend. Acad. Sc., Paris 134(16):913-915. Dahl, E. 1949. Epicaridea and Rhizocephala from northern Norway with a discussion on llie bathymetrical distribu- tion of Rhizocephala. Troms0 Mus. Arrshefter 69(1); 1-44. Damboviceanu, A. 1928. Variations des substances pro- te'iques coagulables par la chaleur dans le plasma des Carcinus nwenas normaux et sacculines. Compt, Rend. Soc. Biol, Paris 98(18):1633-1635. 1932. Composition chimique et physico-chimique du liquide cavitaire chez les Crustaces Decapodes. Arch, rournaines pathol e.xptl microbiol 5:239- 309. Darnell, R. M. 1959. Studies of the life history of the blue crab {Callinectes sapidus Rathbun) in Louisiana waters. Trans. Amer. Fish. Soc. 8 8(4): 294 —304. Daugherty, F. M., Jr. 1949. Blue crab investigation 1948— 49. Ann. Rept. Mar. Lab. Texas Game, Fish and Oyster Comm, for 1948-49. (Unpublished). 1952. The blue crab investigation, 1949-1950. Texas Jour. Scl 4(1): 77-84. Daugherty, S. J. 1969. Aspects of the ecology, life history, and host-parasite relationship of Loxothylacus panopaei (Sacciilinidae) in Chesapeake Bay. M. A. Thesis. College of William and Mary, Williamsburg, Va. 68 pp. 160 Lawler and Shepard Day, J- H. 1935. The life-history of Sacculina, Quart. J. Micro. Sci. 77:549 583. Delage, Y. 1883a. Sur I’anatoinie et la physiologic de la Sacculine a fetal adulte. Compt. Rend. Acad. Sc., Paris 97:961 -964, 1883b. Sur la Sacculine interne, nouveau stade du developpernent de la Sacculina carcini. Compt. Rend. Acad. Sc., Paris 97:1012-1014. 1 883c, SurPemhryogenie dela Sacculina carcini, Crustace endoparasile de fordrc nouveau de Kentrogon- ides. Compt. Rend. Acad. Sc., Paris 97: 1 145 -1 148. 1883-1884d. Note sur la Sacculine. Bull. Soc. Linn. Normandie r 3 e serie, 8:1 7-24. 1 884. Evolution de la sacculine {Sacculina carcini Thomps.) crustace endoparasile de Tordre nouveau des kentrogonides. Arch. Zool Exp. Gen., 2. s. 2:417-736. 1885a. De I’existence d’unsystemenerveu.xchez le Pe/lo^fls/^r.Contribution k Thistoire des kentrogonides. Compt. Rend. Acad. Sc., Paris 100(1 5): 1010-1012, 1885b. On the existence of a nervous system in Peltogaster; a contribution to the history of the Centro- gonida,/4wn. and Mag. Nat. Hist., 5 s. (90), 15:495-498. (Translation of previous entry.) 1 886a. Sur la Sacculine. Compt. Rend. Acad. Sc., Paris 102:1336-1338. 1886b. Sur le systfeme nerveux et sur quelques autres points de I’organisation du Peltogaster (Ralhke). Contributions k I’ordrc des Kentrogonides. Arch. Zool. Exp Gen. 2. s. 3:17-36. 1886c. Sur le syst^me nerveux el sur quelques autres points de Porganisation du Peltogaster (Ralhke); contribution a I’histoire des kentrogonides. v4rc/z. Zool. Exp. Gen., 2, s. 4:17-36. . 1900. La question de la Sacculind Bull. Soc. Zool. France 25:72-73. Dillon, W. A. & D. E. Zwerner. 1966. Contributions to the biology of the sacculinid parasite Loxothylacus panopaei (Gissler, 1884) Boschma, 1928. Trans. Arner. Microsc. Soc. 85(3);407-4l4. Dornesco, G. T, & E. Fischer-Piette. 1931. Donnees cytol- ogiques sur les “racines” de la Sacculine, Crustac^ para- site. Bull. Histol. Appl. 8:213—221. Drilhon, A. 1936. Quelques constantes chimiques et physicochimiques du milieu interieur de crabe sacculine, Carcinus moenas. Compt, Rend. Acad. Sc., Paris 202(1 1):981 -982. 1937. Influence du parasitisme sur Pequilibre mineral des tissus (la sacculine chez le crabe). Compt. Rend. Acad. Sc., Paris 204(1 1):913-915. & E. A. Pora. 1936a. Sacculine et Crabe. filude chimique ct physico-chimique. Trav. Sta. Biol. Roscoff 14:111-120. & 1936b. Ionisation et tampons du milieu interieur du crabe parasite, Carcinus moenas sacculine. Compt. Rend. Acad. Sc., Paris 202(14): 1309— 1311. Duboscq, 0. 1901. Sur revolution du testicule chez la Sacculine. Arch. Zool Exp. Gen., 3. s-,9. Notes et revue, XVII-XXIX. 1912. Sur les peltogaslrides des cotes de France: Peltogaster (Chlorogasrer) pruvoti n. sp., Peltogaster {Chlorogaster)delagei n. sp., et Septosaccus cuenoti n. g., n. sp.Arch. Zool Exp. Gen., 49, 5. s.,v. 9(1):9— 15. 1937. Gemmosaccus nov. nom. au lieu de Chloro- gasterDu'o. pour \es Peltogaster du typeP. sulcatus. Zool Mededeel Rijksmus. Nat. Hist., Leiden 19(3— 4); 180. Durand, D. & A. Veillet. 1972. La spermatog^nese chez les Rhizocephales Gemmosaccus sulcatus (Lilljeborg) et Sacculina carcini Thompson. Bull Acad. Sco. Lorr. Set 11(2):119-131. Fischer, E. 1927a. Sur le tlssu constituant les “racines” endoparasitairesde la sacculine. Compt. Rend, Soc. Biol, Paris 96(5):329-330. 1927b- Connexions tissulaires intimes entre la sacculine et le crabe qu’elle parasite. Les foUicules lageni- formes. Compt. Rend. Soc. Biol, Paris 97(21 ):203— 205. 1928a. Association chez le crabe d’un tissu parasite et d'une trame conjonctive, analogue a certains processus tumoraux. Bull Ass. Franc. Etude Cancer, an. 21, 17: 468-470. 1928b. Sur les interactions tissulaires: Les effets du parasitisme de la Sacculine surle tissue conjonctif du Crabe. Compt. Rend. Soc. Biol, Paris 98:662-664. 1928c. Sur les modifications d’un organisme (crabe) envahi par un parasite (sacculine). Compt. Rend. Soc. Biol, Paris 98(1 1);837-839. Fischer-Piette, E. 1930. Sur la glande lymphatique des crabes sacculines. Bull la. maritime rnusee natl hist. nat. St. Servan 5:23-25. Fox, H. M, 1953, Haemoglobin and biliverden in parasitic cirripedc Crustacea. Nature, London (4343), 171: 162— 163. Foxon,G. E. H. 1940. Notes on the life history of Sacculina carcini Thompson. J. Marine Biol Ass. U. K. 24(1): 253-264. Fratello, B. 1966. [Cytotaxonomy and systematics of Rhizo- cephala (Crustacea. Cirripedia)] .Boll Zool 33: 147-148. 1967, Osservazioni cariologiche sui Crostacei Rizocefali. Pubbl Staz. Zool Napoli 35(3):300-306. 1968. Carioiogia e tassonomia dei sacculinidi (Cirripedi, Rizocefali). Caryologia 21 :359-367. 1969. Cariology and sistematics in Crustacea Rhizocephala. A/rf Ass. genet, ital 14:38-40. Frentz, R. I960. Contribution a iVtude biochimique du milieu interieur de Carcinus maenus Linixe.Edit. Societe d'impressions typographiques. Nancy, pp. 1-176. A. Veillet. 1953. Teneur en lipides et d^ter- minisme des caracteres sexuels externes chez le crabe Bibliography of Rhizocephala 161 Carcinus nmenas Pennant, parasile par le rhizoc4>hale SaccuJina carcini Thompson. Compt, Rend. Acad. Sc., Paris 236(22): 2 168-2 170. George, A. 1. 1959. Heiemsaccus rugirwsu.^ (Boschrna) a rhizocephalan parasite of the crab Neptmus sanguinolen- tus (Herb St). J. Zool Soc. India 1 1(2): 1 71-204. Gerbe, J. 1862. Sur les Sacculina. Extrait d’une leitre de M. J. Gerbe, adressee a M. van Beneden. Bull Acad. Roy. Belgique, 2. s., 13:247-248. Giard, A. 1873. Sur Ics cirripedes rhizoce^phales. Compt. Rend. Acad. Sc., Paris 77(1 7): 945 -948. 1874a. Sur I’embryoge'nie des rhizoce^hales. Compt. Rend. Acad. Sc., Paris 79(1): 44 -46. 1874b. Sur Pethologie de la Sacculina carcini Compt. Rend. Acad. Sc., Paris 79(4): 241 -243. 1886a. Sur I’oricntation dc Sacculina carcini Compt. Rend. Acad. Sc., Paris 102(1 9): 1082-1085, 1886b. De Pinfluence de certains parasites rhizo- ce'phalessur Ics caractcres sexuels exte'rieurs de leur hote. Compt. Rend. Acad. Sc., Paris 103(1): 84— 86. 1887a. De [’influence de certains parasites rhizo- cephalessur les caracferes sexuels exterieurs de leur hote. (Abstract of Giard, 1886b) Centralbi Bakteriol I.J., 1(1 4): 4 27-428. 1887b. La castration parasitaire et son influence sur les caracteres exterieurs du sexeinale chez les crustaces decapodes. Bull Scient. Dept. Nord. v. 18, 2. s.,v. 10 (1-2): 1-28. 1887c. Sterllitat durch Parasiten verursacht und ihre Einfluss auf die ausseren Charaktere der Mannchen bei den Dekapoden Crustaceen. (Abstract of I887d) Nature. Rundschau 2(28): 227—228. 1 887d. Parasitic castration, and its influence upon the external characters of the male sex, in the decapod Crustacea. (Transl. of \%%lb) Ann. and Mag. Nat. Hist., 5.S. (113),v. 19:325-345. 1887e. Sur les Danalia, genre de cryptonisciens parasites des sacculines. Bull Scient. Dept. Nord., v. 1 8, 2. s.,v. 10(l-2):47-53. 1 887f. Sur la castration parasitaire chez VEupagu- rus bernhardus Linne' et chez la Gebia stellata Montagu. Compt. Rend. Acad. Sc., Paris 104:1 1 13—1 1 15. 1888a. La castration parasitaire. Nouvelles re- cherches. Bull Scl France et Belg. 19, s. 3, 1:12-45. 1888b. Analyse critique de description de Sylon challengeri, n. sp., par le Dr. P. P. C. Hoek. Bull Soc. France-Bclgique, s. 3,1 ; 433 437. Gissler, C. F. 1884a. The crab parasite, Sacculina. Ant Naturalist 18(3):225-229. Goldschmidt, R. 1920. Mechanisnius und Physiologic der Geschlechtsbestimmung. Berlin . Goldschmidt, R. B. 1923. The mechanism and physiology of sex determination. (Trans, by W. J. Dakin). Methuen, London. 259 pp. Goldschmidt, R. . Die sexuellen Zwischeristufen. Julius Springer, Berlin, 528 pp. Guerin-Ganivet. J. 1910a. La repartition geographique du Triangulus munidae G. Smith, rhizoc^phale parasite des especes du genre Munida Leach. Bull Inst. Oceanogr. (189):3pp. 1910b. La repartition geographique du Triangulus munidae G. Smith, rhizoce^hale parasite des espbees du genre Munida Leach. Trav. Scient. Lab. Zool et Physiol Maritimes Concarneau 2(4) :3pp. . 1911. Contribution a I’etude systematique et biologique des rhizocepbales. Trav. Scient. Lab. Zool et Physiol Maritimes Concarneau 3(7): 1 97. 1912. Les pelt ogast rides du Musee Ocebno- graphique de Monaco. 7>flrv. Scient. Lab. Zool et Physiol Maritimes Concarneau 4(5): 8 pp. Gunter, G. 1950. Seasonal population changes and distribu- tions as related to salinity, of certain invertebrates of the Texas Coast, including the commercial shrimp. Publ Inst. Mar. Scl Univ. Texas 1(2): 7— 51. Hafele, F. 1911. Notizen ilber phylogenetisch interessante Rhizocephalen. Zool Anz., Leipzig 38(7-8): 1 80— 185. 1912. Anatomic und Entwicklung eines neuen Rhizocephalen Thompsonia japonica. Abhandl K. Bayer. Akad. Wissensch. Math.-Phys. Kl, Suppl-Bd. 2, 7. Abhandl: 25 pp. Hale, H. M. 1927. The Crustaceans of South Australia. 1. Harrison Weir, gov’t printer, North Terrace. Adelaide, 201 pp. Halstead, B. W. 1965. Poisonous and venomous marine animals of the world. 1. Invertebrates. U. S. Gov’t. Ptg. Office, Washington, D.C. 994 pp. Hanslrom,B. \939. Hormones in Invertebrates. The Claredon Press, Oxford, England. 198 pp. Harris, A. H. & J. G. Ragan. 1970. Observations on the ecology and incidence of Loxothylacus texanus (Bosch- ma), parasitic in the blue crab {Callinectes sapidus Rathbun) in south Louisiana. Proceedings SW Assoc. Parasit. (Abstract). Hartnoll, R. G. 1962. Parasitic castration of Macropodia longirostris {F^bnciu&) by a sacculinid. (French summary) Crustaceana 4(4); 295— 300. 1967. The effects of sacculinid parasites on two Jamaican crabs. J. Linn. Soc., London, (Zoology), (310), 46:275-295. Haswell, W. A. 1889. On Sacculina infesting Australian crabs. Proc. Linn. Soc. N. South Wales (1888), 2. s.,v. 3:1711-1712. Heath, J. R. 1971. Seasonal changes in a population of Sacculina carcini Thompson (Crustacea: Rhizocephala) in Scotland. / Exp. Mar. Biol Ecol 6: 15-22. Henry, D. P. 1954. Cirripedia: the barnacles of the Gulf of Mexico. V. S. Fish Wildl Serv., Fish. Bull 55:443- 446. 162 Lawler and Shepard Herberts, C. 1974. Etude du Crustace Decapode Cardmis mediterraneus et du Rhizoceplmle Sacculim carcini. Ana- lyse des serums du crabe et de son parasite. Compt. Rend. Acad. Sc., Paris 279(20): 1625- 1628. Hesse, E. 1867. Observations sur des crustace's rares ou nouveaux des Cotes de France. Description de deux sacculinidiens, d*un Peltogaster, d’un Polychliniophile et de deux cryptopodes nouveaux. Ann. ScL Natur. (5) Zool 8;199--216- Hiraiwa, Y. K. 1924. Parasitic castration in Pachygrapsus crassipes, “aburagani” by Succulina (Japanese text). Dobuts. Zasshi, Tokyo (433), 36: 468-471. 1 939. Effect of Rhizocephala and parasitic Isopoda on the sexuality of higher Crustacea. A review (Abstract of report before 2- Sc. Cong. Japan, Genetics, Feb. 23) (Japanese lexi) Japan. J. Genetics 15(4): 24 1—247. Hoek, P. P. C. 1888. Description of Sylon challengeri n. sp., a parasitic cirriped. Rep. Scient. Results Voyage H. M. S. Challenger 1873-76, Zool., v. 24, App, A, pp. 919-926. Hoshino, K. 1965. On the root-system of Sacculina con- fragosa Boschma, a rhizocephalan parasite attached to Pachygrapsus crassipes Randall. Recherches Crust. No. 2: 3 - 9 ^ Hubert, M., C. Chassard-Bouchaud & J. Bocquet-Vedrine. 1976. Aspects ultra structuraux des hemocytes de Carci- nusrnaenas L. (Crustace decapode), parasite par Sacculina carcini Thompson (Crustace Cirripede): activite reaction- elle, genes« de collagene. Compt, Rend. Acad. Sc . , Paris, Sdr.D.,283(7):789-792. Ichikawa, A. & R. Yanagimachi- 1957. The sexual nature of a rhizocephalan, Pel togas terella socialis. J. Fac. Sci. Hokkaido Univ., Ser. 6,Zool. 13:384-389. & 1958. Studies on the sexual organiza- tion of the Rhizocephala. 1. The nature of the “testes” of Pel togas terella socialis Kruger. Annot. Zool. Japan 31:82-96. & 1960. Studies on the sexual organi- zation of the Rhizocephala. II. The reproductive function of the larval (cypris) males of Peltogaster and Sacculina. Annot. Zool Japan 33(1):42— 56. Kampen,P. N. van &H. Boschma. 1925. Die Rhizocephalen der Siboga Expedition. Siboga-Exped. Uitkom. Zool, Nederl. Oost-Indie (1899—1900), Livr. 101, Monogr. 31 bis., 61 pp. Kauri, T. 1966. On the sensory papilla x organ in cirriped larvae. Crustaceana 11:11 5-122. Kleinholz, L. H. 1942. Hormones in Crustacea. Biol Revs. 17:91-119. KoUer, G. 1938. Hormone bei wirbellosen Tieren. Akad. Verlag. Leipzig. 143 pp. Kollmann, M. 1908. Recherches sur les leucocytes et le tissu lymphoide des Invertebres. Ann. Sc. Nat. Zool 8(9); 1 -240. 1909. Notes sur les rhizocephales. Arch. Zool Exp. G^., an. 41, 5 s., v, 1, Notes et Rev. (2):xliii- xlix. 1910. Remarques sur quelques rhizocephales et speciaJement sur Lernaeodisats. Ann. Sc. Nat., Paris, 2001. (1909), an. 85, 9 s., v. 1 0(3-6):255-273. Kossinann, R. 1872. Beitrage zur anatomic der schmarotzen- den Rankenfiissler. Verb, phys.-med. Ges. Wurzburg, N. F.,3:296-335. 1872—1873, Beitrage zur anatomic der schmar- otzenden Rankenfiisser. Arb. Zool Inst. Wurzburg 1: 97-137. 1874. Suctoria und Lepadidae. Untersuchungen liber die durch Parasitismus hervorgerufenen Lfmbildungen in der Familie der Pedunculata. Arb. Zool Inst. Wurzburg 1:179-207. Kruger, P. 1912. Uber ostasiatische Rhizocephalen. Beitrage Naturgesch. Ostasiens, hrsg. von F. Doflein. Abh. math.- phys. Kl. K. Bayer. Akad. Wiss., II. Suppl.-Bd, 8. Abh. pp. 1-8. 1940. In: Bronn, H. G., Klassen und Ordnungen des Tierreichs, Bd. 5, Abt. 1, Buch 3, Tcil 3. 560 pp. Kuris, A. M. 1974. Trophic interactions: similarity of para- sitic castratorS to parasitoids. Quart. Rev. Biol 49(2): 129-148. Lang, A. 1892. Traite' d’anatomic comparcc crustaces. Deuxieme Fascicule, Paris, pp. 355—356, 449—453. La Vaulx, R. de. 1922 . L*intersexualite. Rev. Ge'n. Sc.Pures et Appliq. 33(6): 1 74-181. Lenel, R. 1954. Sur I’absorption des pigments carotenoides du crabe Carcinus moenas Pennant par son parasite Sacculina carcini Thompson. Compt. Rend. Acad. Sc., Paris 238(8):948-949. Leuckart, K. G. 1859a, Carcinologisches. Einige Bemerkun- gen uber Sacculina Thomps. {Pachybdella Dies., Peltogas- ter Rathke p. p.). Arch. Naturg., Berlin, 25. J., 1:232— 266. 1859b. Observations on the genus Sacculina, Thompson {Pachybdella, Diesing; Peltogaster Rathke). Ann. and Mag. Nat. Hist., Zool., 3. s. (24), 4:422— 429. (Translation of previous entry). Levy, R. 1923. Sur la loxicite des tissus de la Sacculina (Sacculina carcini) vis-a-vis du crabe (Carcinus moenas) et sur la recherche de re'actions d’immunite' chez ce dernier. Bull Soc. Zool France 48:291—294. 1924, Sur la constatation de differences d’ordre physico-chimique entre le se^'ium des crabes Sacculines et celui des crabes nortnaux. Bull Sac. Zool France 49:333-336. Lilljeborg, W. 1859a. Les genres Liriope et Peltogaster, H. Rathke. Upsala. 36 pp. 1^596. Liriope och. Peltogaster H. Rathke. Ofvers. K. Vetensk.-Akad. Fork 16(4):213-217. 1 860a. Om de parasitiska Crustaceerna: Liriope och Peltogaster, H. Rathke. Arsskr. K, Vetensk-Soc. Upsala \ :\^1-\A1. Bibliography of Rhizocephala 163 lilljeborg, W. 1860b. Ucber Liriope und Peltogaster Rathke. (Abstract of \ 2>59h) Ztschr. Ges. Naturw. 1 5(2-3); 153- 154. 1861a. Supplement au memoire sur les genres Liriope ct Peltogaster. H. Rathke. Upsala. 30 pp. 1861b. Liriope et Peltogaster, H. Rathke. iVova Acta Reg. Soc. Set LJpsal ser, 3»3:l-35. 1861c. Supplement au memoire sur les genres Liriope et Peltogaster, H. Rathke. Nova. Acta Reg. Soc. Set Upsai ser. 3, 3:73—102. 1861d, Om Liriope och Peltogaster, H. Rathke. (Abstract of 1861b) Porh. Skand. Naturforsk. (1860), 8. M^de: 677-685. 1861e. Supplementary memoire on the genera Liriope Peltogaster, Rathke, (Trans, of 1861c)>l«/7. and Mag. Nat Hist. 3. s. (37), v. 7:47-63. 1864a. Memoire sur les genres Liriope ei Pelto- gaster. Rathke. (Same as 1861b). Ann. Sc. Nat., Zool. 5. s., V. 2 (5-6): 289-324. 1864b. SuppleWnt au memoire sur les genres Liriope et Peltogaster (Same as 1861c). Ann. Sc. Nat., Zool., 5. s., V. 2 (5-6): 325-355. Malm, A. W. 1881. Om Cirrepeder funna vid Bohuslans Kust. Gdteborgs Naturhist. Mus. zool.-zoot. Afdel. 3: 26-32. Manwcll, C. 8c C. M. Baker. 1963. Starch gel electrophoresis of sera from some marine arthropods: studies on the heterogeneity of hemocyanin and on a “ceruloplasmin- like protein,” Comp. Biochem. Physiol. 8(3): 193— 208. Matsumoto, K. 1952. On the saccuUnization of Charybdis japonica (A. Milne- Ed wards). Biol. J. Okayama Univ. 1:84-89. 1954. Neurosecretion in the thoracic ganglion of the crab, Eriocheir japonicus. Biol. Bull 106:60—68. McGinitie, G. E. 1955. Distribution and ecology of the marine invertebrates of Point Barrow, Alaska. Smithson. Misc. Coll 128(9):1-201. McMullen, J. C. & H. T. Yoshihara. 1970. An incidence of parasitism of deepwater king crab, Lithodes aequispina, by the barnacle Briarosaccus callosus. J. Fish. Res. Bd. 27:818-821. Menzel, R. W. 1971 . Checklist of the marine fauna and flora of the Apalachee bay and the St. George Sound area. Dept, of Oceanography, Fla. St. Univ. 126 pp. More, W. R. 1969. A contribution to the biology of the blue crab (Callinectes sapidus Rathbun) in Texas, with a description of the fishery. Texas Parks & Wildl Dept. Tech. Ser. Mouchet, S. 1931 . Spermatophores des Crustaces Decapodes Anomoures et Brachyoures et castration parasilaire chez quelques Pagures. Annls. Stn. Oceanogr. Salammbd 6: 1-203. 1934. Castration parasitaire de VEupagurus pri- deauxi par le Peltogaster curvatus. Trav. Stat. Biol Roscoff n\\\ -19. Muller, F- 1862, Die Rhizocephalen, eine neue Gruppe schmarotzender Kruster. Arch. Naturg., Berlin 28:1-9. 1863. Die zweite Entwickelungsstufe der Wurzel- krebse (Rhizocephalen). Arch. f. Naturgesch. Jahrg. 29: 24-33. Nagabhushanam, A. K. 195S. Sacculina gonoplaxae Gue'rin- Ganivet, 1911, a rhizocephalan parasite new to British waters. London (4601) 181:57—58. Nayar, N. B. & 0. N. Gurumani. 1956. On the occurrence of three Sacculina parasitising the edible crab Neptunus sanguinolcntus, J. Bombay Nat. Hist. Soc. 53(4): 730- 732. Nielsen, S.-O. 1970. The effects of the rhizocephalan para- sites Rathke and Gemmosaccus sulcatus (Lilljeborg) on five species of paguridan hosts (Crustacea Decapoda). Sarsia (42): 17— 32. Nilsson-Cantell, C. A. 1926. Ueber Veranderungen der sekundaren GesclUechtsmerkmale bei Paguriden durch die Einwirkung von Rhizocephalen. Ark. Zool, Stock- holm, 18(3), pt. A, art. 13. pp. 1—21. Oguro, C. 1955. On the sacculinization of the hermit crab Eupagurus ochotensis (Brandt). Annot. Zool Japan 28(2):100-105. 1956. On the change caused by Rhizocephalan parasites in the hermit crab Eupagurus lanuginosus. J. Fac. Set Hokkaido Univ., Ser. VI., Zool. 12:511-515. Okada, Y. K. & Y. Miyashila. 1935a. Ueber die vollstHndige Geschlechtsumkehr bei den mit Sacculina infizierten MSnnchen der japanischen Wollhandkrabbe, Eriocheir japonicus deWaan. Biol Zentralbl 55(1 1— 12):625-634. & 1935b. Sacculinization \w. Eriocheir japonicus de Haan, with remarks on the occurrence of complete sex-reversal in parasitized male crabs. Mem. Coll Sc., Kyoto Imp. Univ., s. B., 10(3): 169—208. & Y. Okasaka. 1939. On the modification of the sexual characters of PetroHsthes japonicus (de Haan) by the parasite Lernaeodiscus cornutus Boschma. L Secon- dary sexual characters and their changes. Scl Repts. Tokyo Bunrika Daigaku, B., 4:63-88. Orton, J, H. 1936. On the rate of growth of Sacculina carcini Thompson in Carcinus maenas (Pennant). Ann. and Mag. Nat. Hist., 10 s. (102), 17:617-625. Park, J. R. 1969. Preliminary study of Biscayne Bay. Quart. J. Fla. Acad. Scl 32(1): 12-20. Pearse, A. S. 1953. Parasitic crustaceans from Alligator Harbor, Florida. Quart. J. Fla. Acad. Scl 1 5(4): 187— 243. & L. G, Williams. 1951. The biota of the reefs off the Carolinas. J. Elisha Mitchell Set Soc. 67(1): 133-161. Pearson, J. 1908. Memoir on Cancer pagurus, the edible crab. no. xvi, Liverpool. Pe'rez, C. 1903. Sur iin isopode parasite d’une sacculine. Proc.-Verb. Soc. Sc. Phys. et Nat. Bordeaux (1902-03): 109-110. 164 Lawler and Shepard Perez, C. 1908. Sur la presence ^\x Lernaeodiscus galatheae Smith dans le golfe de Gascogne. Proc.-Verb. Soc. Sc. Phys. etNat (1907-1 908):27 -28. 1922. Sur deux Crustace's parasites de la Galathea squamifera Leach. Bull Sac. Zool France 47(5): 132- 133. 1926- Sur quelques caracteres sexuels secondaires chez les Galathees. Compt. Rend, Acad. Sc., Paris 183: 86-89. 1927. Pleopode de type lemelle chez un crabe male sacculine'’. Bull Soc. Zool France 52(1): 29-31. — 1928a. Sur le cycle cvolutifdes rhizoce'pliales du genre Chlorogaster. Compt. Rend. Acad. Sc., Paris 187(18):77l-773. 1928b. Notes sur les Epicaridcs et les Rhizo- cephales des cotes de France. 11. Nouvelles observations sur les parasites de VEupagums bernhardus. III. LEupagu- ms evanensis et ses parasites. IV. Diogenes pugilator et Septosaccus cuenoti. Bull Soc. Zool France 53:523— 528. 1929. Differences sexuelles dans rornementation et dansle systeme pigmentaire chez un Crabe oxyrhynque (Macropodia rostraia L.). Compt. Rend. Acad. Sc,, Paris 188:271-273. 1 930. Sur Tovogenese chez les Rhizocd'phales du genre Chlorogaster. Compt. Rend. Soc. Biol, Paris 104: 1273- 1275. 1931a. Notes sur les Epicarides el les Rhizo- ce’phales des cotes de France. VI. Epicarides fourvoyes dans le coelome des Crustace's Decapodes. Vll. Peltogaster et Liriopsis. Bull Soc. Zool France 56(6): 506—5 12. 1931b. Sur les racines des rhizocephaies parasites des pagures. Compt. Rend. Acad. Sc., Paris 192(12): 769-772. 1931c. Statistique d’infestation des pagures par les Chlorogaster. Compt. Rend. Acad. Sc., Paris 192(20): 1274- 1276. 1931 d. Remplacement successif des sacs visceraux chez les Gi/orogasre/vrhizoce'phales parasites des pagures. Compt. Rend. Acad. Sc., Paris 192(26): 1753— 1755. 1931e. Organogencse dcs bourgeons de remplace- ment chez les Chlorogaster, rhizoce^phales parasites des pagures, Compt. Rend. Acad. Sc., Paris 193(3): 195—197. — 193 If. Les rhizocephaies parasites des pagures. Verhandl Schweiz. Naturf, Gesellsch. (112) Jahres- versamml., 24-27 Sept., Ui Chaux-de-Fonds), 261—276. 1932a. Sur les racines des rhizocephaies parasites des pagures. Arch. Zool Ital, Torino 16(3— 4): 1315— 1318. 1932b. Cycle evolutif des rhizocephaies du genre Chlorogaster. Arch. Zool Ital, Torino 16(3— 4); 1319— 1329. 1932c. Idem. Atti 11. Cong. Internal. Zool (Padova, 4-11 Set. 1930), 3:1319-1329. 1932d. Sur quelques caracteres differenticls des sexes chez le Bernhard I’Eremite. Compt. Rend. Acad. 5c., Paris 194:1187-1189. I932e. Caracteres diffeVentiels des sexes des Pagures du genre Diogenes. Compt. Rend. Acad. Sc., Paris 195:1044-1046. - 1933a. Restriction de la fecondite' ches les femelles d’un crabe, Macropodia rostrata, sous Tinfluence de la sacculine, Compt. Rend. Soc. Biol, Paris 112(10):958- 960. 1933b, Processus de resorption phagocytaire des oocytes dans Tovaire chez les Macropodia sacculinees. Compt. Rend. Soc. BioL, Paris 112:1 049— 1051. 1933c. Action de la sacculine sur les caracteres sexuels exteVieurs du Pachygrapsus marrnoratus. Compt. Rend. Soc. Biol. Paris 1 13(25): 1027-1 029. 1934a. Atrophic de Tovaire chez le crabe Macro- podia rostrata sous I’influence de la sacculine. (In Hom- mage 'a la memoire du Professeur Jean Canlacuzene. Paris. 601-609.). 1934b. Notes sur les epicarides et les rhizocephaies des coles de France. VIIL Infection simultanee des pagures par un Athelges et un rhizoce^hale. Arch. Zool Exp. Gen. 75(32): 541 -565. 1935a. Titres et Travaux Scientifiques, fasc. II. Hermann et Cie, ed,, pp. 112—260. 1935b- Sort des racines du Peltogaster apres la chute du sac visce'ral. Compt. Rend. Acad. Sc., Paris 20l(4):286-288. 1935c. Sur une Eriphia spinifroms sacculinec. Bull Trav. Station Exper. Aquic, et Peche Castiglione (Algene)(]933):49-58. 1937. Sur les racines des Rhizocephaies. Xlf Congresint. Zool, Lisbonne, C. R. 3:1555—1563. 1939. Demonstration de stades internes du Septo- saccus cuenoti Uuhoscq, Peltogaster parasite du Diogenes pugilator Roux. Bull. Soc. Zool France 64(2): 137, 1941 . Recherchessur les Rhizocephaies. I. Rameau re'eurrent et formations ovariennes des racines chez le '‘Peltogaster paguri*' Mem. Acad. Sc. 65:1—29. & E. Basse. 1928. Sur un monstre double de sacculine. Bull Soc. Zool France 53(3): 139-145. Perry, H. M. 1975. The blue crab fishery in Mississippi. Gulf Research Reports 5(l):39-57. Phang, V. P. E. 1975. Studies on Thompsonia sp. a parasite of the edible swimming crab Portunus pelagicus. Malay. Nat. /. 29(2):90-98. Pilsbry, H. A, 1907. The barnacles (Cirripedia) contained in the collectioos oCthe U. S. National Museum, EuJi U S Nat. Mm. 60:1-121, Pochon-Masson, J. 1971. Re"serves glycoge'^niques dans le materiel peTiflagellaire du Spermatozoide des Cirripedes. J. Microsc. (Paris) 12(1):139-144. , J. Boequet-Vedrine, & Y. Turquier. 1969. Con- Bibliography of Rhizocephala 165 tribution a Tetude du spermatozoide des crustaces cir- ripedes,pp. 205— 209.//?: Baccetti, B. (Ed.), Comparative sperrmtology. Proc, Intermt. Symp., Rome and Siena 1—5 July 1969. Accademia Nazionale dei Lincei, Rome. Academic Press, New York and London. Popov, V. K. 1929. Rhizocephala and Bopyridae of the bay of Sevastapol (Russian text). Trudy Sevastapol. Biol. Stantsii 1 : 1 —26. Potts, F. A. 1906. The modification of the sexual characters of the hermit crab caused by the parasite Peltogaster (castration parasitaire of Giard). Quart. J. Micr. Sc., n. s. (200), 50(4)1599-622. 1909. Observations on the changes in the common shore-crab caused by Sacculina. Proc. Cambridge Phil. Soc. 15(2):96-100. 1912. Mycetomorpha, a new rhizocephalan (with a note on the sexual condition of Sylon). ZooL Zahrb. Abt. Syst. 33:575-594. 1914. Thompsonia, a little known Crustacean parasite (Preliminary note). Proc. Cambridge Phil. Soc. 17:453-459. 1915. On the rhizocephalan genus Thompsonia and its relation to the evolution of the group. Publication Carnegie Inst. Washington (212), 8:1—32. Ragan, J. G. & B. A. Matherne. 1974. Studies on Loxothyla- cus texanus, pp. 185—203, In: R. L. Amborski, M. A. Hood, & R. R, Miller (eds.), Proceedings of Gulf coast regional symposium on diseases of aquatic animals, April 16-17, 1974, Louisiana State University, Publ. No. LSU- SG-74-05. Ramult, M- 1935. Observations on the embryonic and larval development in Sacculina in changed osmotic conditions of medium. Bull. Intern Acad. Polon 2:87—109. Rasmussen, E, 1959. Behaviour of sacculinized shore crabs {Carcinus niaenas Pennant). Nature 1 83 :479— 480. Rathke, H. 1 842. Beitrage zur vergleichenden Anatomic und Physiologic, Reisebemerkungen aus Skandinavien, nebst eincm Anhange uber die riickschreitende Metamorphose der Thiere. VI. Peltogaster paguri. N. Schrift. Naturf Gesellsch. Danzig 3(4): 105- 111. Reinhard, E. G. 1939- Rediscovery of the rhizocephalan Peltogaster paguri on the North American coast. Science, n.s.(2300), 89:80-81. 1940a. The endoparasitic development of Pelto- gaster paguri. Amt. Rec. 78(4): 104. 1940b. Studies on the rhizocephalan Peltogaster paguri. Anat. Rec. 78(4): 125. 1942a. The endoparasitic development oi Pelto- gaster paguri. J. Morphol. 70(1):69— 79. i942b. The reproductive role of the complemen- tary males of Peltogaster. J. Morphol 70:389—402. 1942c. Studies on the life history and host- parasite relationship of Peltogaster paguri. Biol Bull 83(3):401-415. 1944. Rhizocephalan parasites of hermit crabs from the northwest Pacific. J. Wash. Acad. Sc. 34(2): 49-58. 1946, Rhizocephala from New England and the Grand Banks. 7. Wash. Acad. Sc. 36(4):127— 131 . 1948. Tortugaster fistulatus n. gen., n. sp., a rhizocephalan parasite of Munidopsis robusta. Proc. Helminth. Soc. Wash. 15(l):33-37. 1949. An analysis of the effects of a sacculinid on the external morphology of Callinectes sapidus Rathbun. Anat. Rec. 105(3): 503. 1950a. An analysis of the effects of a sacculinid parasite on the external morphology of Callinectes sapidus Rathbun. Bull 98(3);277-288. 1950b. Two species of Lermeodiscus (Crustacea: Rhizocephala) from North Carolina and Florida. Proc. Helminth. Soc. Wash. 17(2): 126-132. 1950c, The morphology of Loxothylacus texanus Boschma, a sacculinid parasite of the blue crab. Texas J. Sci. 2(3):360-365. 1951. Loxothylacus, a parasite of the blue crab in Texas. Texas Game and Fish 9(5): 14- 17. 1952. Notes on regeneration in the Rhizocephala (CrusUce-d). Proc. Helminth. Soc. Wash. 19(2): 105-108. 1954. A case of conjoined twins in Loxothylacus (Crustacea, Rhizocephala). Proc. Helminth. Soc. Wash. 21(2):67-71. 1955. Some Rhizocephala found on Brachyuran crabs in the West Indian region. J. Wash. Acad. Sci. 45:75-80. 1956. Parasitic castration of Crustacea. Exptl Parasit. 5:79-107. 1958. Rhizocephala of the family Peltogastridae parasitic on West Indian species of Galalheidae. Proc. a S. Nat. Mus. 108:295-307, &, T. von Brand. 1942. A hyperparasitic amoeba in Peltogaster. Proc. Helminth. Soc. Wash. 9(1): 27— 28. & 1944, The fat content of Pagurus parasitized by Peltogaster and its relation to theories of sacculinization. Physiol Zool 1 7(1 ): 31-41. & F. W. Buckeridge. 1950. The effect of para- sitism by an entoniscid on the secondary sex characters of Pagurus longicarpus, J. Parasit. 36(2): 131-138. & J. T. Evans. 1951. The spenniogenic nature of the “mantle bodies” in the aberrant Rhizocephalid Mycetomorpha. J. Morph. 89:59—69. & P. G. Reischman, 1958. Variation in Loxo- thylacuspanopaei{G\sslei), 2 i common sacculinid parasite of mud crabs, with the description of Loxothylacus perartmtus, n. sp.7. Parasit. 44(l):93-99. & T. Stewart. 1956. The hermaphroditic nature of Thompsonia (Crustacea Rhizocephala) with the de- scription oi Thompsonia cubensis, n. sp.iVoc. Helminth. Soc. Wash. 23:162-168. 166 Lawler and Shepard Reischman, P. G. 1959. Rhizocephala of the genus Pelto- gasterella from the coast of the state of Washington to the Bering Sea. D'oc. K. Akad. Wetensch., Amsterdam (C),62; 409-43 5. Reverberi, G. 1941. Sul determinismo die caratteri sessuali secondari e sulla femminilizzazione da parassitimo nei crostacei. jBo//. Zool 12(5-6): 187— 198. 1942. Annotazioni biologiche sulla Parthenopea subterranea Kossman e sulla Thompsonia rnediterranea Caroli e dati sulla modificazioni dei caratteri sessuali prodotte da parassiti sui loro ospiti. Pubbl Staz. Zool Napoli 19:89-102. 1943. Sui significato della “castrazione paras- sitaria.” La tiansformazione del sesso nci Crostacei paras- sitai da Bopiridi e da Rizocefali Pubbl Staz. Zool Napoli \9\22S-3\6. 1944-45- La determinazione del sesso nei Cros- tacei e i fenomeni della castrazione parassitaria. Rend. Inst. Lombardo di Scienze e Lettere (Cl. di Scienze) 78(1):217- 246. 1949. La ‘"'castrazione paraSvSitaria” e la determi- nazione del sesso nei cwitaLcel Attualita Zool (1942- 1949), 1:1-116. (Arch. Zool. Ital., 34, Suppl.) 1950a. Parassitismo, iperparassitismo e “castra- zione parassitaria” nei crostacei. Boll Zool 17(4—6): 88-90. 1950b. Problem! del sesso nei crostacei. (La “castrazione parassitaria”). Quaderno Accad. Naz. Lincei, Roma (22) 347:38-55. Robertson, D. 1894. Jottings from my notebook, Sacculina carcini, Thompson. I'rans, Nat. Hist. Soc. Glasg., N.S., 4:79. Robson, G. C. 1911. The effect of Sacculina upon the fat metabolism of its host. J. Micro. Sci. 57:267-278. 1912. The effect of Sacculina upon the fat- metabolism of the crab Inachus mauritanicus. Brit. /Iss. Adv. Sc. (81. Meet., Portsmouth, Aug. 31-Sept. 7, 1911), p. 415. Rudloff, O, & A. Veillet. 1954. Influence du Rhizocephale Septosaccus cuenoti sur le metabolisme lipidique du Pagure Diogenes pugilator. Compt. Rend. Soc. Biol, Paris 148:1464-1467. Salt, G. 1927. The effects of stylopisation on aculeate Hymenoptera. /. Expti Zool 48:223-331. Samuelson, T. J. 1970. Peltogaster curvatus Kossmann, a rhizocephalan parasite new to the Norwegian fauna with notes on the synonymy of one of the hosts, Pagurus prideauxi Leach. Sarsia 43:8 1—86. Sandifer,P. A. 1973. Distribution and abundance of decapod crustacean larvae in the York River Estuary and adjacent lower Chesapeake Bay, Virginia, 1968—1969. Chesapeake ScL 14(4):235-257. Schimkewitsch, W. 1895, Ober die untersuchungen von J.O. Pekarsky iiber die Entwicklung von Peltogaster pagurl Trav. Soc. Nat. Petersourg 2^:21^. Schram, T. A. 1972. Record of larva of Peltogaster paguri Rathke (Crustacea, Rhizocephala) from the Oslofjord. Norweg. J. Zool 20(3):227 232. Semitu.K. 1944. Sacculinization, with a note on the mecha- nism of sexual differentiation in the host (in Japanese). Annot. Zool Jap. 22:175—184. Shiino, S. M. 1931. Studies on the modification of sexual characters in Eupagurus samuelis caused by a rhizo- cephalan parasite Peltogaster sp. Mem. Coll Sc. Kyoto Imp. Univ. 7(2):63-101. 1943. Rhizocephala of Japan. J. Sigenkagku Kenkyusyo 1(1): 1-36. Shirase, S. & R. Yanagimachi. 1957. The early development o( Peitogasterella socialis Kruger (a rhizocephalan). Zool Mag. Tokyo 66:253-257. Sindermann, C. J. & A. Rosenfield. 1967. Principal diseases of commercially important marine bivalve Mollusca and Crustacea. U. S. Fish Wildl Serv., Fish. Bull 66:335— 385. Smith, G. W. 1906. Rlrizocephala. Fauna und Flora des Golfes von Neapel, Monographe 29:1—123. 1907. The fixation of the cypris larva of Sacculina carcini (Thompson) upon its host, Carciniis moenas. Quart. J. Micr. Sc., n. s. (204), 51(4):625-632. 1910. Studies in the experimental analysis of sex. Part 2. On the correlation between primary and secondary sexual characters. Quart. J. Micr. Scl 54:590—604. 1910. Studies in the experimental analysis of sex. Part 3. Further observations on parasitic castration. Quart. J. Micr. Sc., n. s.,(218), 55(2):225-240. 1911. Studies in the experimental analysis of sex. Part 7. Sexual changes in the blood and liver of Carcinus maenas. Quart. J. Micr. Sc., n. s. (226), 57(2):25 1—265. 1913. Studies in the experimental analysis of sex. Part 10, The effect of Sacculina on the storage of fat and glycogen, and on the formation of pigment by its host. Quart. J. Micr. Sc., n. s. (234), 59(2): 267 -29 5. 1915. The genus Lernaeodiscus (F. Muller, 1 862). J. Linn. Soc., London, Zool. (2l9),32:429-434. Stead, D. G. 1900. Contributions to a knowledge of the Australian crustacean fauna. No. II. On Sacculina, para- sitic upon Pilumnopeus serratifrons. Proc. Linn. Soc. N. South Ifa/ei (1899) (96), 24(4): 687-690. Thompson, J. V. 1 836. Natural history and metamorphosis of an anomalous crustaceous parasite of Carcinus maenas, the Sacculina carcini Entom. Mag. 3(5):452— 456. Uglow, R. F. 1969. Haemolymph protein concentrations in portunid crabs. 3. The effect of Sacculina. Comp. Bio- chem. Physiol 31:969-973. Uspenskaia, A. V. I960. Parasitofaune des Crustaces benthiques de la mer de Barents (Expose preliminaire). Ann. Parasitol Hum. Comp. 35:221-242. 1963. Parasite fauna of benthic crustaceans from the Barents Sea. (Russian ie\\)Moskva, Leningrad. 127 pp. Bibliography of Rhizocephala 167 Van Engel, W. A. 1972. Subclass Cirripedia. p. 143. In: Wass, M. L. (ed.), A check list of the biota of lower Chesapeake Bay. Va. Inst. Mar. Set, Spec. Sci. Rep. No. 63. , W. A. Dillon, D. E.Zwerner & D.Eldridge. 1966. Loxothylacus panopaei (Cirripediae, Sacculinidae) an in- troduced parasite on a xanthid crab in Chesapeake Bay, U.S.A. Crustaceana 10:1 1 1—1 12. , R. L. May, J. Whitten & D. D. Liindt. 1967. Distribution of sacculinid-infected mud crabs in Chesa- peake Bay. Virginia J. Sc., n.s., 18(4): 166-1 67. Veillet, A. 1941. Observations sur les crabes sacculines et la Sacculine. I. Bull. Inst. Oceanogr. Momco^No. 802, 8 pp. 1943a, Note sur le dimorphisme des larves de Lernaeodisais galatheae Norman et Scott et sur la nature des “males larvarie.s” des Rhizoc^phales. Bull. Inst. Oceanogr. Monaco 841 ; 1 -4. 1943 b. Sur le parasitisme simultane du crabe Carcinus rnoenas L. par la sacculine Sacculina carcini Th. et par I’isopode ^picaride Portunion moenadis Giard. Bull. Inst. Oceatwgr. Monaco. No. 855, 8 pp. . 1945. Recherches sur le parasitisme des Crabes et des Galathees par les Rhizocephales et les Epicarides. Ann. Inst. Ocean., Monaco 22(4): 1 93— 341 . 1947. Metamorphose de la larvecyprisdu Rliizo- cephale Septosaccus cuenoti Dub. parasite du pagure Diogenes pugilalor. Compt. Rend. Acad. Sc., Paris 224: 957 959. . Sur I’elevage des larves des Rhizocephales. Bull. Inst. Oceanogr. Monaco, No, 990; 1 —6. 1952. Metamorphose de la larvecyprisdu Rliizo- cephale Gemmosaccus sulcatus Uiljborg. Compt. Rend. Acad. Sc., Paris 234: 1310-1312. 1955. Remarque sur rinfluence de la Sacculine sur les organcs cndocrines des crabes. Bull. Soc. Scient. Nancy, N. S. 14:73-74. . 1 960. Observation de la fixation des larves males chez le Cirripede parasites Septosaccus cuenoti Duboseq. Dimorphisme des larves de Rliizocephales. Bull. Soc. Sci. Nancy, N. S. 19(2-3): 90-9 3. 1962. Sur la sexualite de Sylon hippolytes M. Sars, Cirripbde parasite dc Crevettes.Cf7mpL Rend. Acad. Sc., Paris 254:176-177. 1963. Metamorphose de la cypris 9 du rhizo- cephale Drepanorchis neglecta Fray.sse.. Compt. Rend. Acad. Sc., Paris 256(7): 1609-1610. & F. Graf. 1958. Degenerescence de la glande androgyne des Cmstac^s decapodes parasites par les Rhizocephales. Bull. Soc. Scient. Nancy. N.S. 18: 123-127. Vernel-Cornuberl, G. 1958. Recherches sur la sexuality du crabe Pachygrapsus marmoratus (Fabricius). >lrc/7. Zool. Exp. Gen. 96:101-276. . 1959. Influence de Pablatioii des pedoncules oculaires sur les caract^res sexuels externes des femelles de Pachygrapsus marmoratus (Fabricius) parasitees par Sacculina carcini (Thompson). Bull Soc. Scient. Nancy, N. S. 18:263-275. Walker, A. M. & A. S. Pearse. 1939. Rliizocephala in Maine. Bull. Mt. Desert Island Biol. Lab. pp. 22-23. (Director s Report for 1938). Wass, M. L. 1955. Decapod crustaceans of Alligator Harbor. Quart. J. Fla. Acad. Sci. 18(3): 129- 176. Wells, H. W. 1966. Barnacles of the Northeastern Gulf of Mexico. Q. J. Fla. Acad. Sci. 29:81-95. Wharfe, J, R. 1977, An ecological survey of the Benthic invertebrate macro fauna of the lower Medway Estuary, Kent./. Anim. Ecol. 46(1):93— 1 13. Williams, A. B. 1966. The Western Atlantic Swimming crabs Callinectes ornatus, Callinectes danae, and a new, related species (Decapoda, Portunidae). Tulane Studies in Zool- ogy 13(3): 83-93. Yanagimachi, R. 1960. The life cycle of Peltogasterella gracilis (Rhizocephala, Cirripedia). Bull. Mar. Biol. Sta. Asamushi ]0(2):109— 1 10. 1961a. Studies on the sexual organization of the Rliizocephala. III. The mode of sex-determination in Peltogasterella. Biol. Bull. 120:272-283. 1961b. The use of cetyl alcohol in the rearing of the rhizocephalan larvae (German summary). Crustaceana 2(l):37-39. 1961c. The life cycle of Peltogasterella {Cimped'm, Rhizocephala). (French summary) Crustaceana 2(3): 183-186. 8l Fujimachi. 1967. Studies on the sexual organi- zation of the Rhizocephala. IV. On the nature of the “testis” of Thompsonia. Annot. Zool. Japan 40:98-104. Zerbib, C., N. Andrieux & J. Berreur-Bonnenfant. 1975. Donnees pr(^liminaires sur Tultrastructure de la gland de mue (organe Y) chez le crabe Carcinus mediterraneus sain et parasite par Sacculina carcini. Compt. Rend. Acad. Sc., Paris 281 : 1 167-1 169. Gulf Research Reports Volume 6 | Issue 2 January 1978 Silica and Ash in the Salt Marsh Rush Juncus roemerianus EC. Lanning Kansas State University Lionel N. Eleuterius Gulf Coast Research Laboratory DOI: 10.18785/grr.0602.07 Follow this and additional works at: http:/ / aquila.usm.edu/ gcr Part of the Marine Biology Commons Recommended Citation Lanning, R and L. N. Eleuterius. 1978. Silica and Ash in the Salt Marsh Rush, Juncus roemerianus. Gulf Research Reports 6 (2) : 169-172. Retrieved from http;//aquila.usm.edu/gcr/vol6/iss2/7 This Short Communication is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf and Caribbean Research by an authorized editor of The Aquila Digital Community. For more information, please contact Joshua.Cromwell(Susm.edu. Gulf Research Reports, Vol. 6, No. 2, 169-172, 1978 SHORT COMMUNICATIONS SILICA AND ASH IN THE SALT MARSH mm,JVNCUSROEMERlANUS F. C. FANNING AND LIONEL N. ELEIJTERIUS Department of Chemistry, Kansas State University , Manhattan, Kansas 66506 and Botany Section, Gulf Coast Research Laboratory , Ocean Springs, Mississippi 39564 ABSTRACT Silica content of living rhizomes from the perennial salt marsh rush Juncus roemerianus had values of 0.34, 0.20, and 0.60% of dry weight in three morphologically distinct populations along the Mississippi coast and was directly related to available silica conteni of the soil (29.7, 17.0, 1 69.6 mg/I OOg soil, respectively). On the other hand, living leaves had about the same average .silica content (0.93, 0.87, 0.90% of dry weight). The silica content of living leaves varied from 0.142% in younger leaves to 1.520% in older ones. Similarly, rhizomes also increased in silica content with age, varying from 0.137% in younger portions to 1.030% for older ones. Mature leaves collected in October all had a higher average silica content (0.7 37%) than those collected in April (0.4 1 3%), indicating that silica content also increases over the growing season, neiannpose.d leaves (dead-standing) had a relatively high silica content of 1.81%, obviously reflecting a loss of organic matter and soluble minerals. Roots contain considerable silica, but reliable results were not possible as the soil could not be completely removed from them. Petrographic microscope studies showed that the silica was clear, colorless and i-sotropic with a refractive index of 1 .43, all properties typical of the mineral opal- No Of-quartz Nv-as present, as occurs in some species of Juncus. The silica was deposited in a sheet made up of small, irregular phyioUths arranged in rows lengthwise in the leaves. Ash percentages were much higher than those for silica and no dcllnite conclusions could be drawn from their variation, in comparison to the maximum silica content of leaves from Juncus interior (3.21%), the concentrations found in leaves of 7. roemerianus were relatively low. INTRODUCTION Silica occurs in numerous vascular plants, including the rushes m/ew/'Weig.and Juncus bufonimh. Lanning (1972) showed that these rushes contained much silica and that the content ot J. interior increased nearly eight-told over the growing season, Both J. interior and 7. bufonius contain opaline silica and o-quartz as do other plants such as Lantana (Lanning et al. 1958). From an extensive review of the literature, Ishizuka (197 1) states that the presence of silica increases the rigidity of the leaves of the rice plant, causing them to become erect. He also cites strong evidence that the presence of silica increases- the resistance of plants to fungal diseases and insect attack. Juncus roemerianus Scheele is a common rush of salt marshes througjiout the coastal area of Mississippi, south- eastern Louisiana and other parts of the Gulf and Atlantic coasts (Eleuterius 1975). Tlie rush grows erect, with stiff terete leaves, that arise terminally from short stems near the surface of the marsh (Eleuterius 1975, 1976). The leaves are coarse, long lasting in some populations, resistant to fungal attack and infrequently grazed by insects. This knowl- edge of J. roemerianus led to the hypothesis that the pres- ence of silica may account for the stiff, persistent and resis- tant leaves. This study was designed to determine: (1) if present, the types and quantity of silica; (2) the ash (A) and silica (S) Manuscript received April 7, 1978; accepted May 25, 1978. contents of the various parts Juncus roemerianus plants; (3) the A and S contents of plants from three morphologi- cally distinct populations; (4) the silica content of the marsh soil in relation to concentration in the rush plants; (5) seasonal differences, if any ; and (6) the A and S contents of young leaves and rhizomes in comparison to older ones. METHODS AND MATERIALS Juncus roemerianus plants were collected from several populations at different locations near Ocean Springs, Mis- sissippi (Figure 1): Belle Fontaine Beach (BFB) marsh; Weeks Bayou (WB) marsh; Salt Flats (SF). Samples with long rhizomes (LR) and a single plant (SP) were taken from Sim- mons Bayou Spoil (SBS). Plants found at WS have mature leaves 3 to 5 feet in length, while those at SF and BFB have leaves 1 to 1.5 and 5 to 7.5 feel in length, respectively. Decomposed leaf material was collected from the peripheral and terminal portions of Simmons Bayou marsh. Specific dates of collections are given with the tables of results. The plant materials were thoroughly washed and then air dried al 110°C. Whole plants were separated into above- ground parts, rhizomes and roots. All plant materials were ground in a Wiley mill before analysis. Silica content of plant material was determined by classical gravimetric tech- niques using platinum crucibles. The material was ashed at about 500°C and the ash treated repeatedly with 6N hydro- chloric acid to remove other mineral impurities. The silica was filtered out and ignited. The silicon dioxide content 169 170 Lanning and Eleuterius 55' 50* 45* 40' Figure 1, The study areas of the tidal salt marsh rush, Juricux roemerianus, were located at BeJIe Fontaine Beach; Weeks Bayou, and Salt Flats. The rush formed monotypic stands at each location. was determined as the difference of weights before and after treatment with hydrofluoric acid. Available silica in soil was determined as acetate soluble silica according to the Imaizumi and Yoshida (1958) modi- fications of Kahlei^s method (1941). A 10-gram sample of soil was extracted by 100 ml of IN acetate buffer of pH 4.0 for 5 hours at 40°C. To a lO-ml aliquot of extract, 5 ml of 0.60N hydrochloric acid and 5 ml of ammonium molybdate (102 grams per liter) were added. After the mixture had stood for 3 minutes, 10 ml of sodium sulfite (170 grams per liter) were added. This mixture was allowed to stand JO minutes, and then absorbance at 634 nm was measured with a Bauseh and Lomb Spectronic 20. The pH of the soil was determined with a Coleman pH meter. Mixtures of equal volumes of soil and water were used for the pH deter- minations. Spodograms were prepared by the Ponnaiya (1951) modification of the Uber (1940) method. The material to be examined was placed between microscope slides, and then ashed in a muffle furnace at 450° to 500°C. The ash was prepared for microscopic examination and photography by removing the upper slide, adding Canada balsam directly to the mass and covering with a cover glass. A petrographic microscope was used lo study the nature of silica deposits. Several specimens from each location were examined. RESULTS AND DISCUSSION Petrographic microscope studies of silica from ash of Juncus roemenatius showed it to be clear, colorless and isotropic with an index of refraction of 1.45. These prop- erties are characteristic of the mineral opal (Lanning et al, 1958). No a-quartz was present although it occurs in Juncus interior Weig. and Juncus hufnnius L. The silica is deposited in sheets which are made up of rows of small irregular phytoliths arranged lengthwise in the leaves. Some fibers arc also present (Figure 2). The soils differed considerably between the three marshes. The soil for SF plants was sandy, had a pH of 9.J0 and an acetate-available silica content of 29.7 mg/lOOg of soil. The BFB and VVB soils were a clay type and had pH values of 5.77 and 7.00, respectively. The acetate-available silica con- tents of BFB and WB soils were quite high, 17.0 and 169.0 mg/lOOg soil, respectively. The leaves of plants in the sandy alkaline soil (SF) grew from 1 to 1 .5 feet tall. The leaves from other locations (see Methods section) were much taller (WB = 3 to 5 feet ; BFB = 5 to 7.5 feet). Results from samples collected in January (Table 1) show that silica concentration is much higher in the leaves than the rhizomes. The leaves of plants from all three loca- tiomshad about the same silica percentage. The WB rhizomes growing in the soil with high available silica content had a much higher percentage of silica than rhizomes from the other loca lions. Ash concentrations were much higher than the silica concentrations and were lowest in SF planis. Living leaf material from the three locations (Table 1) all showed a considerably higher silica percentage in samples collected in October than those collected in April. This Short Communications 171 Figure 2. Spodogram of silica deposited in a Juncus leaf (100 X). Note tlie small, irregular phytoliths (P) and some fibers (hyaline streaks, F). TABLE 1. Ash and silica content of living Juncus roetnerianus from Belle Fontaine Beach (BFB) marsh, Weeks Bayou (WB) marsh, and Salt Flats (SF) on I>eei Island. Collections were made during January 1977. (imposition of living leaves taken in April (A) and Octo- ber (O) 1976 from the same three populations are also shown. Sample No, Leaves Rhizomes % Ash % Silica % Ash % Silica BFB-1 4.13 0.93 3.53 0.21 Bl'B 2 4.28 0.33 5.10 0.21 BFB-3 4.39 0.79 4.47 0.28 BFB-4 5.12 0.80 4.20 0.23 BFB-5 4.75 0.94 3.24 0.08 BFB 6 5.25 0.94 4.43 0.18 Average 4.65 0.87 4.16 0.20 VVB-1 4.93 0.95 5.34 0.40 WB-2 5.40 1.24 5.31 0.93 WB-3 4.90 0.86 4.74 0.43 WB-4 5.35 0.89 5.02 0.36 WB-6 4.70 1.11 6.55 1.28 Average 5.10 0.90 5.50 0.60 SF-! 4.26 0.90 3.57 0.22 SF-2 4.36 1.22 5.12 0.37 SF-3 3.80 0.88 3.64 0.43 SF-4 4.15 1.03 4.03 0.37 SF- 5 3.98 0.83 4.27 0.42 SF-6 3.85 0.71 4.02 0,23 Average 4.07 0.93 4.11 0.34 BFB-^A 4.93 0.56 BFB-0 4.47 0.69 WB-A 4.69 0.34 WB-0 4.40 0.83 SF-A 3.95 0.34 SF-0 3.68 0.69 increase over the growing season corresponds with results obtained by Lanning (1972) for other Juncus plants and Lanning and Linko (1961) {or Sorghum plants. The results of studies on plants to compare the silica concentrations of younger and older plant materials are shown in Table 2. For this study the rhizomes were cut in two, and the older halves analyzed separately from the younger. In all cases older leaves and rhizomes had consid- erably higher silica percentages than younger ones. Decom- posed leaf material had a much higher silica percentage than the living material analyzed. Loss of organic matter and soluable mineral matter obviously resulted in this higher silica percentage. Silica constitutes a small fraction of the mineral matter in the plants since the ash percentages were much higher. Root analyses were not accurate since it was not possible to remove all the soil. Ash content of the roots was abnormally high indicating that silica must also be too high to be accurate. TABLE 2. Ash and silica contents of young and old leaves, riii/oines and leaves of a single clump [clone or single plant (SP)] about 45 cm in diameter, of Juncus roernerianus collected from Simmons Bayou Spoil (SBS). Long rhizomes (LR), 30 to 45 cm in length, bearing intact shoots and roots were dug from a larger clump located at SBS and separated into younger and older parts. Com- parative samples were also taken from three populations; Belle Fontaine Beach (BFB) marsh. Weeks Bayou (WB) marsh and Salt Flats (SF) at E>car Island. Composition of decomposed (dead- standing, BFB) leaf material is also shown. All samples were taken during June 1977. Plant Part %Ash % Silica Single plant (small clump) — SBS-SP Young leaves 4.85 0.142 Old leaves 4.99 0.599 Dead leaves 4.63 0.783 Rhizomes 6.15 0.317 Roots 10.40 1.25 Long rhizomes with intact shoots and roots — SBS-LR Younger half of rhizomes 3.97 0.270 Older lialf of rhizomes 3.30 0.441 Leaves on younger half of rhizomes 4.94 0.960 Leaves on older half of rhizomes 4.47 1.520 Roots 15.36 2.53 Long rhizomes with intact shoots and roots from three populations BFB; Rhizomes — younger half 7.35 0.137 Rhizomes - older half 9.92 0.506 Roots 13.30 0.632 WB: Rhizomes - younger half 8.95 0.418 Rhizomes - older half 9.10 0.447 Roots 15.90 1.18 SF: Rhizomes - younger half 7.78 0.705 Rhizomes - older half 9.63 1.03 Roots 14.09 1.82 Decompo.sed leaf material — BFB 3.93 1.81 ACKNOWLEDGMENT The technical assistance of John Caldwell and Dolores Smith is acknowledged and appreciated. 172 Lanning and Eleuterius REFERENCES CITED Eleuterius, L. N. 1975. The life history of the salt marsh rush, Juncus roemerianus. Dull, Toney Dot. Club 102:135-140. . 1976, The distribution Juncus roemerianus in tlie salt marshes of North America. Chesapeake Sci. 17:389-292. Imaizumi, K. & S. Yoshida. 1958. Edaphological studies on silicon supplying power of paddy fields. Bull. NatL Insi. Agric. Sci. Ser. B (Soils Ferl) No. 8 (Japan); 261-301 . Ishizuka, Yoshiaki. 1971. The physiology of the rice plant. Adv. Agron. 23:241-315. Kahler, M, L. 1941, Determination of soluble silica in . Indus- trial and Engineering Chemistry: Analytical Edition. American Chemical Society, Washington, D.C, 13:536. Lanning, E, C. 1972. Ash and silica in Juncus. Bull. Torrey Bot. Club 99:196-198. , R. W. X. Ponnaiya & C. F. Crumpton. 1958. The chem- ical nature of silica in plants.. Plant Physiol. 33{5);339— 343. & Yu-Yen Linko. 1961. Absorption and deposition of silica by four varieties of sorghum. J. Agric. Food Chern, 9:463-465. Ponnaiya, B. W. X. 1951. Studies in the genwi Sorghum: The cause of resistance in sorghum to the insect pest Aniheriogna indica M. J. Madras Univ. Sect. B, XXI, No. 2 (India): 203-21 7. Tiber, F. M. 1940. Microincineration and ash analysis. Bot. Rev. 6:204-226. Gulf Research Reports Volume 6 | Issue 2 January 1978 Occurrence ofMysidopsis almyra Bowman^ M. bahia Molenock and Bowmaniella brasiliensis Bacescu (Crustacea^ Mysidacea) from the Eastern Coast of Mexico W Wayne Price University of Tampa DOI: 10.18785/grr.0602.08 Follow this and additional works at: http:/ / aquila.usm.edu/ gcr Part of the Marine Biology Commons Recommended Citation Price, W. 1978. Occurrence oiMysidopsis almyra Bowman, M bahia Molenock and Bowmaniella brasiliensis Bacescu (Crustacea, Mysidacea) from the Eastern Coast of Mexico. Gulf Research Reports 6 (2): 173-175. Retrieved from http:// aquila.usm.edu/gcr/vol6/iss2/ 8 This Short Communication is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf and Caribbean Research by an authorized editor of The Aquila Digital Community For more information, please contact Joshua.Cromwell(Susm.edu. Gulf Research Reports, Vol. 6, No. 2, 173-175, 1978 OCCURRENCE 0¥ MYSIDOPSIS ALMYRA BOWMAN, A/. BAHIA MOLENOCK AND BOWMANIELLA BRASILIENSIS BACESCU (CRUSTACEA, MYSIDACEA) FROM THE EASTERN COAST OF MEXICO W. WAYNE PRICE Department of Biology, University of Tampa, Tampa, Florida 33606 ABSTRACT Tl^ree species of mysids, Mysidopsis almyra, M. bahia and Bowmaniella hrasilicnsis are recorded for the first time from four locations along the eastern coast of Mexico. Data on geographical distribution, population structure, length, brood si/.e, and morphological variation are given. INTRODUCTION Only two mysid species have been reported from the shallow waters along the eastern coasl of Mexico between the Rio Grande and the Yucataii peninsula. Bacescu (1968) reported Bowmaniella dissimilis (Coifmann) from Veracruz, Veracruz, and Price (1975) reported Metamysidopsis swifti Bacescu from Tuxpan and Punta de Anton Lizardo in Vera- cruz. This paper reports the collection of three additional mysid species from four locations along the eastern coast of Mexico in May 1973- MATERIAL AND METHODS Collections were made with a 1.5 m hand-drawn beam trawl (Renfro 1963) and preserved in 5% formalin. Temper- ature was measured with a hand-held mercury bulb ther- mometer and salinity was measured with a rcfractometer. RESULTS i\ND DISCUSSION Collection sites are shown in Figure 1. The northern- most collection was made 1 km westofLaPesca.Tamaulipas (23°50'N; 97“46'W) in 1 m of water over an oyster-shell bottom. Thirty Av/o Mysidopsis almyra Bowman were found here. Collections were made at two locations on the western shore of Laguna de Tamialiua, Veracruz, a lagoon situated between Tampico and Tuxpan. Ninety-two M. Almyra and 16 Af. bahia Molenock were taken 3 km north of San Geron- imo (21°33'30''N; 97®36'30"W) in a natural oil seep area. The water depth was 1,5 m and the bottom consisted of shell mixed with nodules of tar-shell conglomerate. Six km north of this site. 155 M. bahia were collected in thick Ruppia maritima beds at the conlluence of Estero Cucharas River and the lagoon in Cucharas. The water depth was 1 .0 to 1.5 m and the bottom was muddy. Four specimen.^ of Bowmaniella brasiliensis Bacescu were collected 3 km north of the jetty at Tuxpan, Veracruz (21®00'N; 97‘'21 'W) at the seaside beach in 1 m ofwater over a sand-shellbottom. Table 1 shows the water temperature and salinity at each location. The previously known geographic ranges of M. almyra and M. bahia extended from the southwestern Everglades, Florida (Bowman 1964; Braltegard 1969, 1970; Odum and Heald 1972) to Baffin Bay, an embayment connecting with Manuscript received July 1 1, 1978; accepted August 15, 1978. Figure I. Location of collecting sites on eastern coast of Mexico. the Laguna Madre on the southern Texas coast (Mackin 1 97 1). This report extends the southern range of these two species approximately 650 km. Bowmaniella brasiliensis was pre- viously reported from Brazil, Georgia, the Caribbean coast of Panama (Brattegard 1974), the Galveston Bay area, Texas (Conte and Parker 1971;Price 1976) and Baffin Bay, Texas (Mackin 1971). The collection locality of B. brasiliensis reported by this study lies between the previously known locations of Baffin Bay, Texas and the Caribbean coast of Panama; this is in all likelihood indicative of a continuous distribution of this species along the coastal areas of the western Gulf of Mexico and Caribbean Sea. The developmental groups for the three mysid species at the four locations are shown in Table 1. For A/, almyra and M. bahia, brooding females comprised the largest portion of the population at each location, and mature individuals greatly outnumbered immatures. Females outnumbered males at each site, attaining ratios of 3.4; 1.0 for M.almyra at San Geronimo and 2. 5: 1.0 for M. bahia at Cucharas. 173 174 Price Table I, Number per developmental group for M. almyra, M. bahia and B. brasiliensis at each location. Developmental groups La Pesca (30^, 14*^) San Geronimo (31^^ 20^) Cucharas (34*, 18*^) Tuxpan (25*, 37*^) M. almyra M. almyra M. bahia M. bahia B. brasiliensis Brooding 99 11 44 5 87 Broodless mature 99 7 18 1 10 Mature 66 7 15 7 37 4 Immature 99 4 9 3 14 Immature 66 3 6 0 7 Total 32 92 16 155 4 ^Water temperature °C ^’Salinity ppt Length measurements (base of eyestalk to posterior ends of uropods, excluding setae) for collections of M. almyra and A/, bahia from San Geronimo and Cucharas revealed that females were larger than males for both species. Lengths of brooding M. almyra averaged 5.6 mm (range 5.0 to 6.7 mm) and mature males averaged 4.9 mm (4.0 to 5.5 mm). The mean length of brooding M. bahia was 5.3 mm (4.0 to 6.6 mm) and the mean length of mature males was 4.4 mm (3.8 to 5.4 mm). In Galveston Bay, Texas during May— June 1971/72 and 1973/74, the mean length of brooding A/. almyra was 4.9 mm (4.3 to 6.8 mm) and the mean length of gravid M. bahia was 5.3 mm (4.3 to 6.3 mm) (Price 1976). The average length of the four mature male specimens of B. brasiliensis was 6.5 mm (6.3 to 6.7 mm). Brood size measurements for the San Geronimo and Cucharas collections indicated that brood size uicreased with increasing length of the female for M. almyra and M. bahia. Mean brood size was 9.0 young (4.0 to 15.0) for AL almyra and 5.5 young (3.0 to 12.0) foryV/. bahia. A similar relationship between brood size and length of female was found for these two species in Galveston Bay, Texas during May— June 1971/72 and 1973/74. However, the mean brood size was 5.4 young (3.0 to 10.0) for M. almyra and 7.0 young (3.0 to 14.0) for M. bahia (Price 1976). Several differences exist between the specimens of M. almyra described by both Bowman (1964) and Brattegard (1969) and those from the present study. Bowman and Brattegard, respectively, reported 6—7 and 6—8 pairs of long slender spines on the telson apex; my adult specimens had 4-5 pairs of spines. Antennal scales as well as the first and fourth male pleopods of specimens examined during this study agreed with Brattegard rather than Bowman. 1 found no distal segment on the antennal scale reported by Bowman. In addition adult males had five setae on the pseudobranchial lobes at the base of the endopods of the first and fourth pleopods rather than six as reported by Bowman; in contrast to Bowman’s specimens the narrow lobe distal to the pseudobranchial lobe of the fourth male pleopod was lacking. Other characteristics agreed with previous descriptions. Specimens of M, bahia from Mexico agreed with those described by Molenock(1969)and Brattegard (1970) except for two characteristics. Molenock and Brattegard, respec- tively, reported 4-5 and 4 -6 pairs of long slender spines on the telson apex; my adult specimens had 3—5 (usually 4) pairs of spines. The curvature of the anterior dorsal margin of the carapace of my specimens was in agreement with Molenock’s illustration which showed it to be broadly tri- angular and slightly produced between the eyestalks. The anterior carapace margin of Brattegard’s specimens was broadly rounded and not produced between the eyestalks. Several differences were noted between the specimens of B. brasiliensis described by Bacescu (1968) and my spec- imens. Bacescu reported 6-7 lateral spines on the telson and 1 found 7-8 spines. The cleft depth/telson length ratio from Bacescu’s illustration was 0.08 as opposed to 0.12 in this study. The lateral lobes of the sinus and the posterior dorsal margin of the carapace of my specimens were more triangular than the oval-shaped lobes of Bacescu’s specimens. The corneal portion of the eye in my specimens was more oblique than the cornea in Bacescu’s .specimens. Other characteristics agreed with the original description. ACKNOWLEDGMENT I wish to express my appreciation to the government of Mexico in permitting this study and to Dr. N. E. Strenth for critically reading the manuscript. Short Communications 175 REFERENCES CITED Bacescu, M. 1968. Contributions to the knowledge of the Gastro- saccinae psammobionte of the tropical America, with the des- cription of a new genus {Bowmaniella , n.g.)and three new species of its frame. lYav. Mus. Hist. Nat. “Grigore Antipa*’ H Bowman, T. E. 1964. Mysidopsis almyra, a new estuarine mysid crustacean from Louisiana and Florida. Tulane Stud. Zool 12(1):15-18. Brattegard, T. 1969. Marine biological investigations in the Bahamas 10. Mysidacea from shallow water in the Bahamas and southern Florida. Fart 1. Sarsia 39:17 106. 1970, Marine biological investigations in the Bahamas 1 1. Mysidacea from shallow water in the. Bahamas and southern Florida. Part 2, Sarsia 41:1^35. 1974, Mysidacea from shallow water on the Caribbean coast of Panama. Sarsia 57:87 1 08. Conte, F. S. & J. C. Parker. 1971. Ecological aspects of selected Crustacea of two marsh ernhayments of the Texas coast. Texas A&M Univ. Sea Grant Program. 184 pp. Mackin. J. G. 1971. /I study of the effects of oil field brine effluents on biotic communities in Texas estuaries. Texas A&M Res. Found. Proj. 735-71 pp. Molenock, J. 1969. Mysidopsis hahia, a new species of mysid (Crustacea: Mysidacea) from Galveston Bay, Texas. Tulane Stud. ZooL 15(3):113-116. Odum, W. E. & E. J. Heald. 1972. Trophic analysis of an estuarine mangrove community. Bull. Mar. Sci. 22(3):671 738. Price, W, W. 1975. A new locality record (or Metamysidopsis swift i Bacescu 1969 (Crustacea: Mysidacea) from the Gulf coast of Mexico. Southwest. Nat. 20(1): 138. . 1976, The abundance and distribution of Mysidacea in the shallow waters of Galveston Island, Texas. Ph.D. Dissertation, Texas A&M Univ. 207 pp. Renfro, W. C. 1963. Small beam net for sampling postlarval shrimp. U.S. Fish Wildl. Ser\>. Circ. 161:86-87. Gulf Research Reports Volume 6 | Issue 2 January 1978 Procedures for Eradication of Hydrozoan Pests in Closed-System Mysid Culture Adrian R. Lawler Gulf Coast Research Laboratory Steven L. Shepard Gulf Coast Research Laboratory DOI: 10.18785/grr.0602.09 Follow this and additional works at: http:/ / aquila.usm.edu/ gcr Part of the Marine Biology Commons Recommended Citation Lawler, A. R. and S. L. Shepard. 1978. Procedures for Eradication of Hydrozoan Pests in Closed- System Mysid Culture. Gulf Research Reports 6 (2): 177-178. Retrieved from http://aquila.usm.edu/gcr/vol6/iss2/9 This Short Communication is brought to you for free and open access by The Aquila Digital Community. It has been accepted for inclusion in Gulf and Caribbean Research by an authorized editor of The Aquila Digital Community For more information, please contact Joshua.Cromwell(Susm.edu. Gulf Research Reports, Vol. 6, No. 2, 177-178, 1978 PROCEDURES FOR ERADICATION OF HYDROZOAN PESTS IN CLOSED-SYSTEM MYSID CULTURE ADRIAN R. LAWLER AND STEVEN L. SHEPARD Parasitology Section. Gulf Coast Research Laboratory, Ocean Springs, Mississippi 39564 ABSTRACT An unidenlilied species of hydrozoan in the family Eirenidae was inadvertently transported to the Labora- tory with a stock of Mysidopsis bahia. The hydrozoan competed for food, ate the young mysids, and subsequently repro- duced extensively. Hermit crabs provided minimal control. A detailed transfer procedure for the mysids eliminated the hydrozoans from cultures; hydrozoans were eradicated from tanks after removal of mysids by using 1 :1200 formalin, hot water, and Clorox. In early 1978, a culture stock of Mysidopsis bahia Molenock was obtained from the Environmental Protection Agency (EPA) Environmental Research Laboratory at Gulf Breeze, Florida, in order to initiate inhouse slocks for toxicity tests. The mysids were placed into six 10-gallon all- glass aquaria with undergravel fillers, a crushed oyster shell substrate, and a salinity of 20- 22 p[)t (Instant Ocean). They were fed Artemia salina Leach larvae twice dally. No problems in rearing occurred for about 2 months. However, during that time a slight brownish growth on the oyster shell in the tanks had become a dense rmt,Arternia quickly disappeared, and the mysid populations were decreasing. Examination of the growth revealed hydrozoans containing Artemia and young mysids, both polyps and medusae were present. Some problems with hydrozoans had occurred previously where our stocks were obtained, and hermit crabs were deployed to all tanks to consume the hydrozoans. Speci- mens of Pagurus sp. and Qibanarius vittatus (Bose) were introduced into all our tanks, eight to ten of the former and two to four of the latter per tank. The crabs ate the hydro- zoans from the bottom outside edges of all tanks, but not in the center or on the vertical glass sides. The mysid popu- lations continued to decrease; the hydrozoans both com- peted i ox Artemia as food and preyed on young mysids. In early May 1978, samples of the hydrozoan were sent to Dr.D. R.Calder. Calder (personal communication) replied that “the specimens belong to the family Eirenidae, which now also encompass the old family Eulimidae, . . . The hydroids of this family are very poorly known, as are the juvenile medusa stages. In fact it is likely that thishydroid is undcscribed.” From 26 May to I June 1978 formalin (Sandifer et al. 1974) was used in the tanks (two tanks treated every other day), according to our procedures, to control the hydro- zoan pest. During the following 5 months there was no recurrence of the pest, and it was considered to be success- fully eradicated. Manuscript received October 1 1, 1978; accepted November 1, 1978. PROCEDURES Procedures developed during this study are presented in a step-by-step order for ease in following. Mysid Handling 1. Set up one or more lO-gallon all-glass aquaria (isolation tanks) with an air stone, no oyster shell, a filter, and the same salinity as the mysid tanks. 2. Filter overnight, then switch to air stone. Introduce four to six hermit crabs whose shells have been scrubbed to remove hydrozoans. 3. Use a small-mesh dip net to collect mysids out of hydrozoan-infested tanks and put them into clean tank with air stone and hermit crabs (to eat transferred hydro- zoans). Feed mysids brine shrimp. Uave mysids in tank at least 2 days. 4. Follow procedures for eradication (see Hydrozoan Eradication section). 5. Net mysids (20 to 30 at a time so pan is not crowded with mysids and debris) out of isolation tank and put into white procelain sorting pan. 6. Sort out all hydrozoans observed in pan and discard. 7 . Then, using a small net(l emsq, small mesh) or eye drop- per, isolate and transfer each mysid individually to a small finger bowl. Remove any hydrozoans observed in bowl. 8. Put mysids in finger bowl back into cleaned original tanks; feed brine shrimp. 9. Do not put hermit crabs back into cleaned tanks as they may have hydrozoans attached to their shells. Hydrozoan Eradication 1. After mysids are removed, add 30 ml formalin per 10- gallon tank (concentration = about 1:1200, due to vol- ume of shell and filter parts). Let stand at least 2 hours. 2. Siphon off water and discard. 3. Remove shell and scald thoroughly with hot water in a bucket, or discard shell. 4. Rinse and scrub tank thoroughly with fresh water. 5. Fill tank with fresh water and add 2- 4 tablespoons of Clorox; put all filter parts into tank. Let stand at least 1 hour. 177 178 Lawler and Shepard 6. Rinse and scrub tank and filter parts with fresh water. Flush tank and filter parts, and shell in bucket, with flowing fresh water for at least 2 to 3 hours. 7. Set up cleaned tank with sea water and filter overnight. Nine days after the above procedures two of six tanks of mysids were lost, presumably due to residual formalin still in the oyster shell substrate or on the glass tank walls or filters. The lemaining four tanks were disassembled, thor- oughly scrubbed (four-five times), and rinsed with fresh water for 5 to 6 hours each; the shell was discarded. Tanks were set up with new shell; no further related die-offs have occurred. Thus, we recommend that the substrate be dis- carded and the tanks and all filter parts be thoroughly scrubbed and rinsed prior to re-introduction of mysids. Over three times the concentration of formalin suggested by Sandifer et al. (1974) was used due to the lack of response by the brine shrimp in the tanks to the formalin. They added 250 ppm ( 1 :4000); we added formalin in 10 ml doses three times (about 1:1200) before a majority of the brine shrimp were affected (swimming ceased), Polychaetes that reside in the shells were added to mysid tanks along with hermit crabs. Althougli the effects of poly- chaetes on mysid cultures are presently unknown, poly- chaetes did not appear to cause any harm in the tanks. Procedures similar to those presented here n>ay be used in eradicating hydrozoan pests in closed-system culture of other invertebrates. ACKNOWLEDGMENTS Dr. D. R. Nimmo of the EPA Environmental Research Laboratory at Gulf Breeze, Florida, kindly provided us with our stock of Mysidopsis bahia. Dr. D. R. Calder of the Marine Resources Research Institute, Charleston, South Carolina, provided information on the hydrozoan. REFERENCE CITED Sandifer, P. A., T. 1. J. Smith & D. R. Calder. 1974. Hydrozoansas pests in closed-system culture of larval decapod crustaceans. Aquaculture 4 :.S5-59. Gulf Research Reports Volume 6 | Issue 2 January 1978 Geographical Definition of Mississippi Sound Charles K. Eleuterius Gulf Coast Research Laboratory DOI: 10.18785/grr.0602.10 Follow this and additional works at: http:/ / aquila.usm.edu/ gcr Part of the Geography Commons, and the Marine Biology Commons Recommended Citation Eleuterius, C. K. 1978. Geographical Definition of Mississippi Sound. Gulf Research Reports 6 (2): 179-181. Retrieved from http;//aquila.usm.edu/gcr/vol6/iss2/10 This Short Communication is brought to you for free and open access by The Aquda Digital Community. It has been accepted for inclusion in Gulf and Caribbean Research by an authorized editor of The Aquila Digital Community. For more information, please contact Joshua.Cromwell^usm.edu. Gulf Research Reports, Vol. 6, No. 2, 179-181, 1978 GEOGRAPHICAL DEFINITION OF MISSISSIPPI SOUND CHARLES K. ELEUTERIUS Physical Oceanography Section, Gulf Coast Research Laboratory, Ocean Springs. Mississippi 39564 ABSTRACT Boundaries for Mississippi Sound are determined by application of definitions, established surveying practices and observations of the physical processes of the area. U.S. Coast and Geodetic charts 1266 (1972 edition), 1267 (1972 edition) and 1268 (1974 edition) were used in ascertaining the boundaries. These boundaries provide a formal geographical definition for Mississippi Sound. The geographical boundaries of Mississippi Sound are ill- defined by natural features especially at the western end. This lack of generally recognized boundaries is a cause of confusion among individuals and agencies with an interest in this water body. Because of this vagueness, it is presently necessary to provide a chart or clear description of the area one refers to as “Mississippi Sound.” Of the several definitions of a sound (Gary et al. 1972), two seem appropriate for Mississippi Sound: (1) “An arm of the sea forming a channel between a maiiiland and an island”; (2) “A long, large, rather broad inlet of the ocean, generally extending parallel to the coast.” Mississippi Sound (Figure 1) is an elongated basin with its major axis parallel to the Gulf of Mexico from which it is partly separated by a series of barrier islands. U.S. Coast and Geodetic charts 1266 (1972 edition), 1267 (1972 edition), and 1268 (1974 edition) were used in determining the boundaries of Mississippi Sound. The line segments shown are what the author proposes to be bound- aries that are justifiable by definitions, accepted surveying practices and observations of the physical processes within the basin. The problem of defining the specific limits between two bodies of water is not always a simple one. The solution lies Manuscript received August 11 , 1978; accepted October 2, 1978. in finding the exact place where the water bodies merger The “headland-to-headland” principle (Shalowitz 1964) has been deduced based on consideration of the physical config- uration of the water bodies. This principle considers the boundary between a tributary water body and a larger water body to be a line joining the headlands of the tributary water body. The headland rule has been applied in various contexts to bays and rivers. Two rules (Shalowitz 1 964) have been established in the case of determining boundaries where rivers flow directly into a water body. Cognizance has been taken internationally of the headland-to-headland principle at the 1930 Hague Conference for the Codification of International Law. The proviso contained in the final report of the Second Sub- committee of the conference slates that “when a river flows directly into the sea, the waters of the river constitute inland waters up to a line following the general direction of the coast drawn across the mouth of the river, whatever its width.” The second rule provides that “if a river flows directly into the sea, the baseline shall be a straight line across the mouth of the river between points on the low-tide line of its banks.” This rule is a recommendation of the Inter- national Law Commission in its final report to the United Nations, as is Article 13 of the 1958 Convention on the Territorial Sea and the Contiguous Zone. The recommend- ation of the International Law Commission is the convention Figure 1 . Mississippi Sound stiowing location of State and natural boundaries. 179 180 Eleuterius that was applied here in determining the boundaries between rivers and Mississippi Sound. A *‘bay'’ according to Geneva Convention (Shalowitz 1 964) is *‘a welbmarked indentation whose penetration is in such proportion to the width of its mouth as to contain landlocked waters and constitutes more than a mere curva- ture of the coast. The area of such an indentation must be as large as, or larger than the semicircle whose diameter is a line drawn across the mouth of the indentation.” This definition was applied to Mississippi Sound in distinguishing between true bays and those areas erroneously named bays. The Sound’s eastern boundary with Mobile Bay is defined by a line connecting the narrowest point between the Ala- bama mainland and Dauphin Island. The same convention would be used in detemiining the boundary between the barrier islands of Dauphin, Petit Bois, Horn, Ship and Cat. The boundary from Cat Island extends from the south end of the south spit to the Isle Au Pitre. This particular boundary, wliile somewhat arbitrary, was decided on for two reasons. First, the south spit of Cat Island which con- tinues south-southwest as a submarine topographic feature serves as a line of demarcation with the Gulf of Mexico. Second, the area south of Cat Island Pass is probably more properly labeled a tongue of the Gulf than an extension of Chandeleur Sound and therefore this boundary appears more appropriate than any alternative. The western boundary of Mississippi Sound is best defined by lines connecting Malheureux Point with Le Petit Island, Le Petit Island with Half Moon Island and Half Moon Island with Light House Point. Malheureux Point was connected with Le Petit Island across the narrowest point of Le Petit Pass. Le Petit Island and Light House Point were connected in a similar manner with Half Moon Island. These boundaries clearly separate Mississippi Sound from Lake Borgne. The boundary with St. Louis Bay is across the bay entrance at its narrowest point. The west entrance to Biloxi Bay is denoted by a line projected north to the mainland from the west lip of Deer Island. The Mississippi Sound/ Biloxi Bay boundary at the east bay entrance is a line connecting the easternmost tip of Deer Island with the mainland at the nearest point. There were two reasons for not projecting this boundary from Little Deer Island: (1) Sound waters pass freely between it and Deer Island; and (2) it is rapidly disappearing (personal observation) and will not long be available for boundary determination. A line projected across the mouths of Pascagoula River com- pletes the assigned boundaries of Mississippi Sound. Bays such as Pascagoula, Point Aux Chenes, Grand, Portersville and Heron are not considered separate and distinct water bodies, i.e., true bays, but integral parts of Mississippi Sound. This decision is based on the failure of the areas to qualify as “bays” under the definition of “bay” according to Geneva Convention. This determination of boundaries provides for the formal geographical definition of Mississippi Sound. The coordin- ates of latitude and longitude for the assigned boundary lines appear in Table 1 . These boundaries are practical in that they are easily remembered and almost as easily located at sea. It is hoped that this geographical definition in clarifying what constitutes “Mississippi Sound” will help end the present confusion. ACKNOWLEDGMENT I wish to thank Mrs. Joyce Edwards for her interest in the work and efficiency in handling the typescript. TABLE 1. Latitude (N) and longitude (W) of ends of assigned boundaries from east to west. From To From To Cedar Point, AL Dauphin Island, AL 30° 17.l' 88° 7.5' 30° 18.6' 88° 8.2' Dauphin Island Petit Bois Island, MS 30° 13.9' 88° 19.3' 30° 12.3' 88° 24,4' Petit Bois Island Horn Island 30° 12.8' 88° 30.4' 30° 13,3' 88° 33.9' Horn Island Ship Island 30° 14.6' 88° 46.5' 30° 14.6' 88° 52.3' Ship Island Cut (Camille Cut) 30° 13.8' 88° 53.6' 30° 13.0' 88° 56.1 ' Ship Island Cat Island 30° 12.6' 88° 59.2' 30° 14.2' 89° 4. o' Cat Island Isle Au Pitre 30° 10.8' 89° 6.8' 30° 9,5' 89° 11. o' Le Petit Island Malheureux Point 30° 4.8' 89° 28.6' 30° 5.l' 89° 29.0' Half Moon Island Le Petit Island 30° 7.6' 89° 26.6' 30° 5.9' 89° 28.l' Half Moon Island Light House Point 30° 8.8' 89° 26.7' 30° 10.4' 89° 27.7' Narrows of Entrance St. Louis Bay 30° 18.4' 89° 17.6' 30° 18.6' 89° 19.5' Deer Island (west) Biloxi (mainland) 30° 21. l' 88° 53.0' 30° 21. r 88° 53.r Marsh Point (mainland) Deer Island (east) 30° 20.3' 88° 47.9' 30° 19.2' 88° 48.9' Creole Gap (LA marsh) 30° 8.5' 89° 12.7' 30° 8.2' 89° 13.2' Grand Pass (LA marsh) 30° 7.7' 89° I4.0' 30° 7.3' 89° 14.7' Three-Mile Pass 30° 3.1 ' 89° 21.4' 30° 2.9' 89° 22.2' Kennedy Lagoon (LA marsh) 30° 3.0' 89° 25.3' 30° 3.1 ' 89° 25.8' Blind Bay (LA marsh) 30° 2.8' 89° 24.5' 30° 3.0' 89° 25.3' Short Communications 181 REFERENCES CITED Gary, M., R. McAfee, Jr. & C. L. Wolf, eds. 1972. Page 676 in Glos- Shalowitz, A. L, 1964, Shore and Sea Boundaries. Vol. II. U.S. saryof Geology. American Geological Institute, Washington, D.C. Department of Commerce, Coast and Geodetic Survey. Gulf Research Reports Volume 6 | Issue 2 January 1978 New Hosts for Lymphocystis Adrian W Lawler Gulf Coast Research Laboratory John T. Ogle Gulf Coast Research Laboratory Chad Donnes DOI: 10.18785/grr.0602.11 Follow this and additional works at: http:/ / aquila.usm.edu/ gcr Part of the Marine Biology Commons Recommended Citation Lawler, A. W., J. T. Ogle and C. Donnes. 1978. New Hosts for Lymphocystis. Gulf Research Reports 6 (2): 183-184. Retrieved from http;//aquila.usm.edu/gcr/vol6/iss2/ 1 1 This Short Communication is brought to you for free and open access by The Aquda Digital Community. It has been accepted for inclusion in Gulf and Caribbean Research by an authorized editor of The Aquila Digital Community For more information, please contact Joshua.Cromwell^usm.edu. Gulf Research Reports, Vol. 6, No. 2, 183-184, 1978 NEW HOSTS FOR LYMEHOCYSTIS ADRIAN R. LAWLER, JOHN T. OGLE AND CHAD DONNES Parasitology and Oyster Biology Sections, Gulf Coast Research Laboratory, Ocean Springs, Mississippi 39564, and Sileni World, Gretna, Louisiana 70053 ABSTRACT Lymphocystis disease is reported for the first time from the Koran angelfish, Pomacanrhus semicirculatus: the Moorish idol, Zanclus canescens; the foureye butlcrnyfish, Chaetodon capistralus; and the orbiculate bat fhh, Plaiax orbicularis. Also, lymphocystis is reported the second time from the queen angelfish, HoIacarUhus ciliaris. All hosts are commercially important exotic aquariuni fishes. INTRODUCTION Lymphocystis is an infectious viral disease of teleosts that causes hypertrophy of connective tissue cells and usu- ally occurs on the fins and skin. The enlarged cells (nodules) eventually slough off; there is no known treatment, but the disease is seldom fatal. A list of hosts reported to be .suscep- tible to the disease since the work of Nigrelli and Ruggieri (1965) was presented by us previously (Lawler et al. 1977). We add four more species to the host list. MATERIALS AND METHODS All the fish examined were imported for sale in tropical fish stores. They were relaxed with MS— 222 (Tricaine methanesulfonate, Cresent Research Chemicals Inc., Scotts- dale, Arizona) and examined alive, so that they could be returned to display tanks. Suspected lymphocystis tissue was removed with forceps, examined under a compound micro- scope for confirmation of lymphocystis, and preserved in 10% buffered formalin for future microscopic examination. No internal organs or gills were examined. The fish were revived in fresh sea water of about the same salinity fioril which they were removed. Preserved lymphocystis tumors were examined with a Siemens lA Elmiskop electron microscope following the procedures of Lawler ct al. (1974). Approximate diameters of viral particles (diameter = distance between opposite vertexes) are enclosed in parentheses in the discussion of each case report. CASE REPORTS 1. Pomacantlius semicirculatus (Cuvier and Valenciennes), Koran angelfish; family Chaetodontidae. The fish occurs from the Red Sea and Indian Ocean to the Indo-Australian Archipelago, the Philippines, China, Okinawa, and Melanesia (Axelrod and F.mmens 1969). On 29 August 1977 two juveniles were examined, both approximately 60 mm long (total length [TL] ). One had hypertrophied cells on the right pectoral fin; the other had Manuscript received October 1 1, 1 978; accepted November 1, 1978. small nodules on all fins. The fish had been imporled from the Philippines through California, and were heavily infected when received. They were held for about 4 weeks prior to microscopic examination, at which time most of (he nodules were gone. The course of the disease (287 nm) in this species appears to last at least 4 weeks. 2. Zanclus canescens (Linnaeus), Moorish idol or toby; family Zanclidae. The fish occurs widely in the tropical Indo-Pacific, from the Red Sea to Mexico (Axelrod and Emmens 1969). On 15 December 1977 one fish was examined. This fish, already infected, was imported from the Philippines through California on 19 November 1977 and was held in a tank at 32 ppt salinity until examination. The fish (70 mm TL) had clumps of lymphocystis cells on the dorsal fin and at the base of the left pecloral fin. Single nodules were scattered on the skin. Il appears, that in this species also, the disease (287 nm) lasts at least 4 weeks. 3. Chaetodon capistratus Linnaeus, foureye bmterflyfish; family Chaetodontidae. The fish occurs in the tropical Atlantic and Caribbean (Axelrod and Emmens 1969). On 21 December 1977 one fish recently imported from Florida was examined. This fish (51 mm TL) had clumps of lymphocystis cells on the left pectoral fin and single nodules scattered on both the dorsal and caudal fins. On 1 0 February 1978, four more fish were received; all had lymphocystis (287 nm). 4. Plat ax orbicularis (Forskal), orbiculate bat fish; family Platacidae. The fish occurs widely from the Red Sea, Indian Ocean, and Indo-Australian Archipelago to the Philippines, China, south Japan, and central to south Pacific islands (Axelrod and Emmens 1969). Three fish were observed infected on 28 January 1978. The fish having the greatest infection (259 nm) died on 19 January 1978 apparently from another cause and was examined microscopically the next day . The fish (64 mm TL) had clumps of lymphocystis cells on the caudal, dorsal, anal, right pectoral, and both pelvic fins; scattered lympho- cystis cells occilncd on the skin. 5. Holacantus ciliaris (Linnaeus), queen angelfish; family Chaetodontidae. The fish occurs from the Bahamas to Brazil, including the Gulf of Mexico (Bohlke and Chaplin 1968). 183 184 Lawler et al. A queen angelfish (210 mm XL) received from Florida was examined on 10 February 1978. It had lymphocystis nodules on the dorsal, anal, and pectoral fins; the infection later spread to the skin underlying the pectorals. The fish died on 3 April 1978, still showing numerous nodules. The course of the disease (287 nm) in this fish was greater than 2 months. This is the second report of lymphocystis on this species, the first being Nigrelli and Ruggieri (1965). 6. Zebrasoma velifentm (Bloch), sailfin tang; family Acan- thuridae. Tlie fish occurs in the tropical Indo-Pacific and Red Sea (Axelrod and Emmens 1969). On several occasions apparent lymphocystis nodules have been observed on fish of this species being held in display tanks. However, at present, lymphocystis has not been confirmed microscopically. DISCUSSION With increased new findings of infected hosts among imported fishes, we agree with McCoskei et al. (1976) who noted that “it is quite likely that many infected species remain unreported, particularly among families of tropical reef fishes. “ Although fish that were already infected, or soon showed signs of infection have been received, it has not been ascertained whether there is more than one strain of lymphocystis in these tropical fishes. Lawler et al.(l974) have already noted viral strain differences occurring in the Gulf of Mexico between two closely related hosts, Balrdiella chrymra (Lacepede) ^i\ 1.5 m but < 3.0 m; > 3.0 m but < 4.5 m; > 4.5 m. Stations in the fourth class were further separated into two groups: those stations located in either the Pascagoula or Gulfport ship channels; those located out- side of the channels. The differences in salinity between surface and near-bottom waters were then determined for all depth-classes on a total of 2,401 pairs of observations. The resulting differences for each depth-class were tallied into monthly frequency distribution tables. The tables con- sisted of three frequency classes: differences > 20.0 ppt, Type A; > 4.0 ppt but < 20.0 ppl, Type B; < 4.0 ppt, Type D. Inspection of the data revealed no pronounced trend differences between depths except for the channel stations; therefore, two composite frequency tables were constructed, one which included data from all stations and the other limited to data from outside the ship channels. RESULTS AND DISCUSSION Table 1 shows that the greatest variability in estuarine type occurs from January through June, corresponding to the high river flow of winter and spring. However, 65.2% of the paired observations taken during March indicated the water column to be well mixed, apparently the result of strong winds usually experienced during this month. Only 1.3% of the March surface-to-bottom salinity differences could class the water column asstratificd.With the exception of January, more than 50% of the paired observations for each month were in the well-mixed class. In January, 9% of the observations showed stratification while the remaining observations were equally divided between partially mixed and well mixed. A sharp change in the water column in July is apparent with 73,0% of the difference in the well-mixed category. TABLE 1. Distribution according to estuary type of observations of surface-bottom salinity differences (percent) from 90 stations in Mississippi Sound, Month Number of Paired Observations Stratified Partially Mixed Well Mixed .lanuary 143 9.0 45.5 45.5 Febiuaiy 265 2.7 42.6 54.7 March 164 1.3 33.5 65.2 April 214 2.3 44.9 52.8 May 248 3.3 42.3 54.4 June 276 1.5 43.1 55.4 July 274 1.1 25.9 73.0 August . 186 0.0 11,8 88.2 September 165 0.0 30.3 69.7 October 121 1.7 7.4 90.9 November 169 0.6 13.6 85.8 December 176 1.1 30.1 68.8 Average 2.05 30.92 67.03 Figure 2. Station locations in Mississippi Sound. Short Communications 1S7 This trend toward vertical homogeneity reaches a peak in October when 90.9% of the differences show a well-mixed system. River flow is at its low during October. The water column, while still dominaiely well mixed, becomes more varied during November and December. Averaging the monthly percentages showed the following; 2.0%, stratified; 3 1 . 0 %, partially mixed , 67.0%, well mixed. To evaluate the influence of stations located in the ship channels on the classification of Mississippi Sound, a second table, Table 2 , was constructed using only salinity observa- tions from stations located outside of the Pascagoula and Gulfport ship channels. The general trend is the same as TABLE 2. Distiibulioi) according to estuary type of observations of surface bottom salinity differences (percent) from 78 stations in Mississippi Sound outside of ship cliannels. Month Number of Paired Observations Stratified Partially Mixed Well Mixed January 132 5.4 42.4 49.2 February 233 0.9 38.2 60.9 March 149 0.7 29.5 69.8 April 192 0.5 41.2 58.3 May 221 0.5 39.8 59.7 June 242 0.4 37.2 62.4 July 241 0.5 18.8 80.7 August 170 0.0 10.0 90.0 September 149 0.0 25.5 74.5 October 111 0.9 4.5 94.6 November 153 0.7 11.1 88.2 December 155 1.3 25.2 73.5 Average 0.98 26.95 71.87 when the channel stations were included; however, there are notably smaller percentages in the stratified and partially mixed classes. The abrupt increase in the well-mixed class for the July- December period is primarily due to a shift from the partially mixed class. The month showing the greatest uniformity of the water column was again October with 94.6% of the salinity differences less than 4.0 ppt. The averaged mniulily percentages in each class show less than 1%, stratified; 26.95%, partially mixed; 7 1 .87%, well mixed. According to the classification of Pritchard (1955), Mississippi Sound varies between types A, B and D but is predominately Type D (well mixed). The period when the water column shows the greatest vadabilily is from January through June — the time of increased river flow. In July, Mississippi Sound becomes notably more homogeneous. This period of tendency to vertical homogeneity , peaking in October, lasts through December. When the channel areas are excluded from the classification procedure, the average of the monthly percentages indicating a stratified system is less than 1% while that for a well-mixed system is approxi- mately 72%. The channels are characteristically stratified or partially mixed. The results of this study were in good agreement with the previous classification by the author (Eleuterius 1978) which confirms that while dominately well mixed, Mississippi Sound also attains the characteris- tics of a partially mixed estuary and, highly localized, characteristics of a stratified estuary. ACKNOWLEDGMENTS 1 wish to express my appreciation to Drs. B. H. Atwell, Lionel Rleulerius and John Wanstralh for their constructive criticisms and helpful suggestions. Thanks are also due Mrs. Joyce Randall Edwards for her usual expert handling of the typescript, proofing and pertinent remarks. REFERENCES CITED Eleiiterius, Charles K. 1976. Mississippi Sound: Salinity distribution Higgins, George G. & Charles K. Eleuierius. 1978. Mississippi Sound: and indicated flow patterns. Mississippi-Alabama Sea Grant Con- Volume, surface area and bathymetric statistics. J. Miss. Aca. sortium Publication MASGP-76-023, Ocean Springs, Mississippi. Scf. Vol. XXHl. (In prc.s!>). 1978. Classification of Mississippi Sound as to estuary type by Pritchard, D. W. 1955. Estuarine circulation patterns. Proc. Amer. vertical salinity Structure, 7. Miss. Acad, Sci. Vol. XXIII. (In press). Sue. O'v. En^. VoL 81, Separate 717, pp. 1-11,