Florida Scientist Volume 39 Fall, 1976 No. 4 CONTENTS Benthic Algae of the Anclote Estuary | II. Bottom-Dwelling Species............ David Hamm and Harold J. Humm 209 »* Vegetation of Southeastern Florida-I. Pine Jog .................. Daniel F. Austin 230 Collection of Postlarval and Juvenile Hoplias malabaricus (Characoidei: Erythrinidae) aI NR esac voi ataiese nat esate Dannie A. Hensley 236 Twinning in the Gulf Coast Box Turtle, Terrapene carolina major................ John K. Tucker and Richard S. Funk 238 Element Content of Hydrilla 2 ATS ae 2 J. F. Easley and R. L. Shirley 240 Effects of a Hurricane on the Fish Fauna E00 0S on ee eee Stephen A. Bortone 245 Partial Food List of Three Species of Istiophoridae (Pisces) eee ortmeastern Gulf of Mexico... ..-........c.ccscececeeceseentineretesseeeres he Jay H. Davies and Stephen A. Bortone 249 The Influences of Intravenously Administered Dimethyl] Sulfoxide on Regional Blood Flow ...... David W. Washington and William P. Fife 254 The Spider Crab, Mithrax spinosissimus: An Investigation Including Commercial Aspects ..................::c::ecceee James A. Bohnsack 259 Occurrence of Bonefish in Tampa Bay.................. Lawrence J. Swanson, Jr. 266 Effects of Sewage Effluent on Growth of LEE 7 re G. Gordon Guist, Jr., and H. J. Humm 267 SE C21 (6 geen ceren- tae na 272 QUARTERLY JOURNAL OF THE FLORIDA ACADEMY OF SCIENCES FLORIDA SCIENTIST QuARTERLY JOURNAL OF THE FLORIDA ACADEMY OF SCIENCES Copyright © by the Florida Academy of Sciences, Inc. 1977 Editor: Harvey A. Miller Department of Biological Sciences Florida Technological University Orlando, Florida 32816 The Fiorina Scientist is published quarterly by the Florida Academy of Sciences, Inc., a non-profit scientific and educational association. Membership is open to indi- viduals or institutions interested in supporting science in its broadest sense. Applica- tions may be obtained from the Treasurer. Both individual and institutional members receive a subscription to the FLorma Scientist. Direct subscription is available at $13.00 per calendar year. Original articles containing new knowledge, or new interpretation of knowledge, are welcomed in any field of Science as represented by the sections of the Academy, viz., Biological Sciences, Conservation, Earth and Planetary Sciences, Medical Sciences, Physical Sciences, Science Teaching, and Social Sciences. Also, contributions will be considered which present new applications of scientific knowledge to practical problems within fields of interest to the Academy. Articles must not duplicate in any substantial way material that is published elsewhere. Contributions from members of the Academy may be given priority. Instructions for preparation of manuscripts are inside the back cover. Officers for 1976 FLORIDA ACADEMY OF SCIENCES Founded 1936 President: Dr. Patrick J. GLEASON Treasurer: Dr. ANTHONY F,. WALSH 5809 W. Churchill Court Microbiology Department West Palm Beach, Florida 33401 Orange Memorial Hospital Orlando, Florida 32806 President-Elect: Dr. RopERT A. KROMHOUT Department of Physics Editor: Dk. HARVEY A. MILLER Florida State University Department of Biological Sciences Tallahassee, Florida 32306 Florida Technological University Orlando, Florida 32816 Secretary: Dr. H. EDWIN STEINER, JR. Department of Education Program Chairman: Dr. MARGARET GILBERT University of South Florida Department of Biology Tampa, Florida 33620 Florida Southern College Lakeland, Florida 33802 Published by the Florida Academy of Sciences 810 East Rollins Street Orlando, Florida 32803 Printed by the Storter Printing Company Gainesville, Florida Florida Scientist QUARTERLY JOURNAL OF THE FLORIDA ACADEMY OF SCIENCES Harvey A. MILLER, Editor Vol. 39 Fall, 1976 No. 4 Biological Sciences BENTHIC ALGAE OF THE ANCLOTE ESTUARY Il. BOTTOM-DWELLING SPECIES Davip HAMM AND HAROLD J. HUMM Department of Marine Science, University of South Florida, St. Petersburg, Florida 33701 ABsTRACT: Some 122 species and 4 varieties of benthic algae are reported from one or more of 10 different substrata, excluding seagrass leaves, or in the drift in the Anclote estuary near Tarpon Springs, Florida Gulf coast. A THREE-YEAR study of the benthic algae of the Anclote River estuary, in- cluding Anclote Anchorage, was completed in 1974. The first part of the study dealt with those benthic algae that occur as epiphytes of seagrass leaves (Ballan- tine and Humm, 1975). All other benthic algae of the area comprise this conclud- ing report. The Anclote estuary is part of the Gulf of Mexico on the north side of Tarpon Springs, Florida. For a period of 4 yr, 1970-74, this general area was intensively studied to provide an accurate base-line description of the environment prior to construction and operation of a power plant (Humm et al., 1971; Baird et al., 1972, 1973, 1974). Power generation was initiated in October, 1974. ENVIRONMENT—Because a detailed description of the Anclote estuary was given by Ballantine and Humm (1975), only a summary is presented. Bottom salinity generally ranged from 23 to 35 °/,, with greater stability in Anclote An- chorage than in the lower part of the river. Salinities below 25 °/,, were brief. Water temperature ranged 11—31°C. Natural depths range to about 2 m and light penetration is such that at least some algae can grow at the maximum depth (except in dredged channels). Nutrients were similar to levels of inshore waters of the Gulf of Mexico, but in the lower Anclote River were somewhat higher and more variable than in Anclote Anchorage (Baird et al., 1973). PROCEDURES—In an effort to include all major habitat types in this study, periodic collections and observations were made in 11 categories as follows: (1) unconsolidated sediments; (2) scattered shells, (3) limestone rock; (4) oyster bars; 210 FLORIDA SCIENTIST [Vol 39 (5) mangrove aerial roots; (6) pilings, seawalls, and other submerged structures; (7) basal part of stems of the salt marsh grass, Spartina; (8) intertidal mud and sand; experimental substrates in the form of (9) concrete blocks and (10) plastic strips; and (11) drift algae. The 28 collection stations that included one to several of these categories were established throughout the estuary as shown in fig. 1. o F.PC. Plant Site Fig. 1. Map of Anclote estuary showing location of the 28 stations at which field studies and col- lections were made and of the town of Tarpon Springs. Stations 5, 6, 7, and 8 were located around an unnamed island just outside the Anclote River mouth on the south side of the channel. This island is referred to as Casuarina Key in the text in allusion to the dense stand of Australian pines, Casuarina equisetifolia, growing upon it. Following is a brief characterization of the collecting stations: Stations 1 and 2: rock jetties exposed to wave action at Howard Park. Station 3: Bird Key with No. 4, 1976] HAMM AND HUMM—BENTHIC ALGAE 211 intertidal Spartina that is relatively exposed. Station 4: chain of five small spoil islands just west of Casuarina Key with mangroves and exposed limestone rocks. Stations 5-8: Around Casuarina Key with red and black mangroves, intertidal sand beaches, oyster shell ridges, and several subtidal bottom types. Station 9: small mangrove island east of Casuarina Key. Station 10: old spoil island with collapsed house, dock, pilings, old oyster shells and chunks of limestone. Station 11: Dead Fish Pass on the north side of the Anclote River near the power plant intake with Spartina and scattered shells. Station 12: intertidal shell-strewn beach on the north side of the Anclote River. Station 13: Paul’s Fish Camp with seawall, boat ramp, docks, pilings, oyster bars and intertidal mud and muddy sand. Station 14: mangrove island opposite Paul’s Fish Camp in protected area with mangroves encrusted with barnacles and oysters. Station 15: base of seawall on north side of the Anclote River near highway bridge, the lowest salinity sta- tion. Station 16: narrow, shallow inlet at Anclote Point fringed with mangroves and saltmarshes and protected from wave action. Station 17: an oyster bar per- pendicular to the shore and intertidal off Bailey’s Bluff. Stations 17-22: off Bailey’s Bluff including an oyster bar that is intertidal and perpendicular to the _ shore (17), a Spartina-covered island (18), intertidal limestone outcropping (19), and seagrass beds with scattered shells at depths of 1-2 m (20-22). Stations 23-28: along the estuary side of the chain of keys constituting the outer (western) bound- ary of Anclote Anchorage having a mangrove fringe, scattered shells, and adja- cent seagrass beds. Field work was normally conducted during periods of low tide. Voucher specimens have been deposited in the herbarium of the Depart- ment of Marine Science, University of South Florida St. Petersburg Campus. ANNOTATED LIST OF SPECIES The 126 taxa of benthic algae identified were distributed among the major groups as follows: Cyanophyta 18, Rhodophyta 50, Phaeophyta 17, Xanthophyta 2, Chlorophyta 39. The monographs of Drouet (1968, 1973) and of Drouet and Daily (1956) were followed in treatment of the Cyanophyta. A key to identifi- cation of nearly all species in the following list is to be found in Dawes, 1974. CYANOPHYTA Order COCCOGONALES Family Chroococcaceae Agmenellum quadruplicatum Brebisson. In upper intertidal muddy sand at sta. 16, where quite abundant (Humm and Hamm, 1976). Agmenellum thermale (Kitzing) Drouet and Daily. Common in intertidal sand and muddy sand as at sta. 16, and colonizing plastic strips put out at sta. 5. Yr around, princi- pally intertidal. Anacystis aeruginosa Drouet and Daily. Evidently the most abundant coccoid blue- green in the estuary; common on mangrove roots at sta. 16, on concrete blocks at sta. 5 and 17, on plastic strips at sta. 5, 8, and 10, on scattered shells at sta. 20-22, and on inter- tidal sediments in many other places. Yr around. 212 FLORIDA SCIENTIST [Vol. 39 Anacystis dimidiata Drouet and Daily. In intertidal sand at sta. 3. Though rarely en- countered because it occurs as solitary cells, pairs, or as groups of four, it is probably com- mon and widely distributed. Anacystis marina Drouet and Daily. From upper intertidal sand at sta. 16 only. Prob- ably common but it is microscopic and difficult to find. Johannesbaptista pellucida Taylor and Drouet. Occasional in the upper intertidal zone of salt marshes or protected beaches. Family Chamaesiphonaceae Entophysalis conferta (Kiitzing) Drouet and Daily. At all sta. Entophysalis deusta (Meneghini) Drouet and Daily. Upon and penetrating shells and other forms of limestone at all sta. with this substrate yr around. Order HORMOGONALES Family Oscillatoriaceae Microcoleus lyngbyaceus (Kitzing) Crouan. One of the most abundant of bluegreens in its many forms (as interpreted by Drouet, 1968) producing intertidal mats, as an epi- phyte, and in the form of massive skeins during summer on seagrasses, especially in the warm water effluent of the power plant. Found on all substrates. Porphyrosiphon notarisii (Meneghini) Kitzing. On aerial roots of black mangroves at sta. 11 only, September, 1973. Schizothrix arenaria (Berkeley) Gomont. Common in the intertidal zone of protected beaches or mangrove areas where it formed a mat that contributed to sand stabilization at most stations the yr around. Schizothrix calcicola (C. Agardh) Gomont. At all sta and on all substrates the yr around as an epiphyte, mixed with bluegreen mats, and boring into limestone and shells. Schizothrix mexicana Gomont. On a cement block, sta. 17, September, 1973, and epiphytic on drifting algae, December, 1972, in the form referred to as Lyngbya gracilis Meneghini in the older literature. Spirulina subsalsa Oersted. In upper intertidal sand of protected beaches the yr around at many sta. Family Nostocaceae Nodularia harveyana (Thwaites) Thuret. In the entire range of the intertidal zone on moist sand or muddy sand at many sta. the yr around. Family Rivulariaceae Calothrix crustacea (Roth) C. Agardh. Common at all sta. as an epiphyte or forming a characteristic black band high in the intertidal zone on pilings, seawalls, mangrove roots, and other substrates the yr around. Family Scytonemataceae Scytonema hofmanni C. Agardh. On and among pneumatophores of black mangroves in mat form at station 18, November, 1972, but not abundant. Family Stigonemataceae Mastigocoleus testarum Lagerheim. Common, boring into limestone at nearly all sta. the yr around, but also found penetrating red mangrove prop roots at sta. 27 and 28 where mixed with Schizothrix calcicola. No. 4, 1976] HAMM AND HUMM—BENTHIC ALGAE 213 RHODOPHYTA Order BANGIALES Family Bangiaceae Erythrotrichia carnea (Dillwyn) J. Agardh. A microscopic epiphyte on larger algae at all sta. the yr around. Erythrocladia subintegra Rosenvinge. These microscopic disk-form plants were en- countered as epiphytes on larger algae in the drift in December, 1972, and in the drift and from concrete blocks in January, 1973. Goniotrichum alsidii (Zanardini) Howe. Epiphytic on larger algae and bryozoa at sta. 17, and on plastic strips put out at sta. 5 and 10 during winter and spring. Order NEMALIALES Family Acrochaetiaceae Achrochaetium sagraeanum (Montagne) Bornet. Occasional as an epiphyte on larger algae during winter at sta. 17. Tetraspores were observed in January, 1973, monospor- angia in December, 1972. Distribution of this species is discussed by Humm and Hamm (1976). Acrochaetium sargassi Borgesen. An epiphyte of larger algae in the drift during winter. Acrochaetium thuretii (Bornet) Collins and Hervey. A few plants found in January, 1973, as epiphytes on larger algae growing on a cement block that had been placed at sta. 5 in December, 1972. Order CRYPTONEMIALES Family Corallinaceae Fosliella atlantica (Foslie) Taylor. On algae in the drift and on plastic strips put out at sta. 3, 5-10. Fosliella farinosa (Lamouroux) Howe. Epiphytic on algae in the drift the yr around. Variety solmsiana (Falkenberg) Taylor was seen occasionally. Jania adherens Lamouroux. In several areas of Anclote Anchorage extensive beds of this species to 50 m sq occurred as loose masses or attached in part over seagrass beds, apparently inhibiting the seagrasses. It was also an epiphyte on other algae attached to concrete blocks put out at sta. 5. Jania capillacea Harvey. On Sargassum and Laurencia in the drift during winter. Family Grateloupiaceae Halymenia floresia (Clemente) C. Agardh. Occasional in the drift, April, 1974. Order GIGARTINALES Family Gracilariaceae Gracilaria foliifera (Forsskal) Borgesen. Although abundant in Tampa Bay, this species is rare in Anclote estuary, even in the drifting algae. Several small plants were found attached to a beer can at sta. 13 in November, 1973. Gracilaria verrucosa (Hudson) Papenfuss. Occasional in the drift. 214 FLORIDA SCIENTIST [Vol. 39 Family Solieriaceae Soliera tenera (J. Agardh) Wynne and Taylor. Though apparently absent from the Anclote estuary during 1972 and most of 1973, this species was found in the drift and attached to shells during the winter of 1973. A heavy stand developed on the rock break- water at Howard Park near sta. 2 at the same time. Family Hypneaceae Hypnea musciformis (Wulfen) Lamouroux. Occasional in the drift, and a few attached plants were found on a beer can near sta. 13 in November, 1973. Like the two species of Gracilaria and Soliera, this species is abundant in Tampa Bay but only occasional in Anclote estuary for reasons not understood. Hypnea spinella (C. Agardh) Kitzing. A single plant attached to a beer can was found at sta. 13 in November, 1973, and it was occasional in the drift. Order CERAMIALES Family Ceramiaceae Callithamnion byssoides Arnott, On large algae in the drift, March, 1974. Ceramium byssoideum Harvey. One of the most common epiphytes on larger algae below low tide at most sta. the yr around and also on non-living substrates. Variety alter- nans Ballantine and Humm was less common. Ceramium corniculatum Montagne. A single record in November, 1972, at sta. 13 on the floating dock at Paul’s Fish Camp. Ceramium fastigiatum (Roth) Harvey. Common on a variety of solid substrates at most sta., especially during the cooler months. Spyridia filamentosa (Wulfen) Harvey. One of the most abundant of the red algae in Anclote estuary, especially during the cooler months when it formed dense, drifting layers over the seagrass beds in shallow water. Centroceras clavulatum (C. Agardh) Montagne. Common on solid substrates in the lower intertidal zone and below at most sta. the yr around. The best development oc- curred on the jetties at Howard Park at sta. 1 and 2. Family Delesseriaceae Caloglossa leprieurii (Montagne) J. Agardh. Abundant on red and black mangrove aerial roots throughout the estuary the yr around. Family Dasyaceae Dasya pedicellata (C. Agardh) C. Agardh. Occasional in the drift during winter and spring; not found attached. Family Rhodomelaceae Acanthophora spicifera (Vahl) Borgesen. Common as a constituent of the drift algae, especially in late fall; on concrete blocks at sta. 10, November, 1973. Bostrichia moritziana (Sonder) J. Agardh. The predominant Bostrichia on mangrove roots at sta. 14, spring, 1973, but by January, 1974, it had been replaced almost entirely by B. radicans. In general, B. moritziana occurred in the more protected areas such as sta. 23 and 24, but was not abundant. Bostrichia radicans Montagne. The second most abundant species in the Anclote estuary, especially on the pneumatophores of black mangroves. It was often mixed with B. scorpioides. About half the plants of B. radicans were the form previously known as B. rivularis Harvey, the latter occasional around the base of the stems of Spartina also. No. 4, 1976] HAMM AND HUMM—BENTHIC ALGAE 215 In well-protected mangrove areas B. radicans forma moniliforme Post was present, often as much as 25% of the forms of B. radicans present. It bore monosiphonous branch tips 15-20 cells long. Bostrichia scorpioides (Gmelin) Montagne, var. montagnei Harvey. This yr around species was the most abundant alga on mangrove aerial roots in Anclote estuary. The plants grew to 6 cm tall in dense tufts or mats. Bostrichia tenella (Vahl) J. Agardh. The least common species of Bostrichia, this plant was occasional at sta. 7, 8, and 9 where it was yr around. Well-developed reproductive plants were found. Chondria baileyana (Montagne) Harvey. A species restricted to winter and spring in this area and found only once in the drift algae in January. Chondria collinsiana Howe. Several plants were found attached to concrete blocks at sta. 5 in March. The blocks were placed there in December. Chondria leptacremon (Melvill) De Toni. A few plants found in the drift in January, 1973. Chondria littoralis Harvey. Common in the drift during winter and spring. In March, 1974, many plants were present on the limestone outcropping off Bailey’s Bluff, sta. 19. Chondria tenuissima (Goodenough and Woodward) C. Agardh. Occasional on shells of living scallops during the fall and winter of 1973. Digenia simplex (Wulfen) C. Agardh. Common throughout Anclote Anchorage the yr around, and at times made up as much as 5% of the drift algae. Attached plants were mostly on shells in seagrass beds. Herposiphonia secunda (C. Agardh) Ambronn. Around the base of aerial roots of black mangroves at sta. 7 and 8, and on concrete blocks placed at sta. 17. Herposiphonia tenella (C. Agardh) Ambronn. More widely distributed in the estuary than the preceding species (or form), and present in abundance the yr around on oyster bars, limestone, pilings, and on larger algae at many stations. Laurencia intricata Lamouroux. Occasional in the drift during winter and spring. Laurencia obtusa (Hudson) Lamouroux. Abundant on the rock jetties at Howard Park, Sta. 1 and 2, during winter and spring 1973-74, but not found at these sta. the year before. One of the two most abundant members of the drift algae, often making up over 50%. Laurencia poitei (Lamouroux) Howe. Although common on seagrasses, this species was not found on other substrates. During the cooler months, however, it often made up 35 to 45% by wt of the drift algae. Lophosiphonia cristata Falkenberg. Found at sta. 16 in March, 1973, attached to a log in the intertidal zone. Lophosiphonia saccorhiza Collins and Hervey. Around the base of Spartina stems at sta. 3, on scattered shells at sta. 20-22, and on concrete blocks placed at sta. 5. Yr around in the lower intertidal zone and below. The rhizoids vary in size and shape with substrate. Murrayella periclados (C. Agardh) Schmitz. Occasional around the base of mangrove roots and extending outward into the intertidal algal mat at sta. 7 and 8 the yr around. Polysiphonia hemisphaerica Areschoug, var. boldii (Wynne and Edwards) Rueness. Occasional on solid substrates and also in the drift. This species until recently has been referred to P. denudata (Dillwyn) Kutzing. Wynne and Edwards (1970) described it as P. boldii. Rueness (1973), after culture and hybridization studies, decided that it was a variety of P. hemisphaerica; P. denudata apparently does not occur south of South Caro- lina. | Polysiphonia echinata Harvey. Common in the drift from November to April, but not found attached in Anclote estuary. Polysiphonia subtilissima Montagne. Yr around at many sta. this is the most euryha- line species of Polysiphonia in Florida. Polysiphonia havanensis Montagne. A few plants were found on the shells of living scallops at sta. 20-22 in September, 1973. 216 HAMM AND HUMM—BENTHIC ALGAE [Vol. 39 PHAEOPHYTA Order EcTOCARPALES Family Ectocarpaceae Bachelotia antillarum (Grunow) Gerloff. On shells and other solid substrates, in- cluding plastic strips placed at sta. 10, November to April. It has been collected in the summer in Tampa Bay, however. Ectocarpus elachisteaeformis Heydrich. On a colonial bryozoan, Zoobotryon verti- cillatum, that was loose and drifting, December, 1972. Ectocarpus intermedius Kitzing. On solid substrates from low intertidal and below, November to April, and also in the drift. This species has been known as E. confervoides (Roth) LeJolis. Earle (1969) pointed out that Ceramium confervoides Roth, upon which E. confervoides is based, is a nominum superfluum. Ectocarpus siliculosus (Dillwyn) Lyngbye. On solid substrates low in the intertidal zone and below, February to April. Not reported south of Tampa Bay or south of Cape Canaveral on the Atlantic coast. Giffordia conifera (Borgesen) Taylor. Occasional on solid surfaces in fall and early winter. For several weeks in the fall of 1973 it was the most common alga on concrete blocks placed at sta. 10. This area is its northern known limit in the Gulf of Mexico (Earle 1969, 1972). Giffordia mitchelliae (Harvey) Hamel. The most abundant of the brown algae. Pres- ent the yr around but best developed from September to May at most sta. on all types of solid substrates. Giffordia rallsiae (Vickers) Taylor. Occasional during the cooler months as small plants less than 5 mm tall on a variety of solid surfaces. Order SPHACELARIALES Family Sphacelariaceae Sphacelaria furcigera Kitzing. Occasional during the cooler months as an epiphyte or around the base of larger algae, or on stones, shells, and woodwork at many sta. Order DICTYOTALES Family Dictyotaceae Dictyota dichotoma (Hudson) Lamouroux. One plant was found in the drift in March, 1974, and it was abundant on the rock jetties at Howard Park, sta. 1 and 2, during the summer of 1975. Order CHORDARIALES Family Chordariaceae Cladosiphon occidentalis Kylin. Common in the drift from January through May; apparently plants that were originally epiphytic on seagrass leaves. It colonized plastic strips at sta. 5 and 10 in February and March, 1974, but was not found on any other non- living substrate. The strips had been put out in February, 1973. Order PUNCTARIALES Family Striariaceae Myriotrichia subcorymbosa (Holden Blomquist. Common the yr around on shoal grass, Diplanthera wrightii, and to some extent on other seagrasses, but also found on oyster shells at sta. 13, and on concrete blocks and plastic strips at sta. 5, 7, 8, and 10 dur- ing winter and spring. No. 4, 1976] HAMM AND HUMM—BENTHIC ALGAE 217 Stictyosiphon subsimplex Holden. Previously reported (Ballantine and Humm, 1975) on seagrass leaves from November to May; recorded here on plastic strips and concrete blocks at sta. 5, 7, 8, and 10 from January to April. Apparently this species and Myrio- trichia subcorymbosa have not been reported previously from non-living substrates. Fiore (1970) has shown by culture studies that M. subcorymbosa is the gametophyte and S. subsimplex the sporophyte of the same plant, but he has not yet published his proposed change of name. | Order Fucales Family Sargassaceae Sargassum filipendula C. Agardh. This most eurythermal species of the genus was found the yr around in the drift, but not attached. During winter and spring, when most common, it made up about 5% of the drift by wt. Sargassum hystrix J. Agardh, var. buxifolium Chauvin. Several large plants were found in the drift in September, 1973. Sargassum pteropleuron Grunow. Occasional in the drift the yr around but more common during winter and spring. Sargassum natans (L.) Gaillon. See S. fluitans. Sargassum fluitans Borgesen. These two pelagic species are occasional in Anclote Anchorage. They are blown in by prolonged westerly winds during the warmer months of - the yr when the Gulf loop current is active. CHLOROPHYTA Order ULoTRICHALES Family Chaetophoraceae Phaeophila dendroides (Crouan) Batters. Recorded as an epiphyte on black mangrove aerial roots low in the intertidal zone at sta. 5 and 6, March, 1973. It is probably common but overlooked because of its microscopic size. Entocladia viridis Reinke. On Laurencia poitei in the drift in March, 1973, but prob- ably widely distributed in the Anclote estuary. Ulvella lens Crouan. On larger algae in the drift, winter and spring. Family Chaetopeltidaceae Diplochaete solitaria Collins. Found once as an epiphyte on drifting algae in Decem- ber, 1972. Easily overlooked as it is one-celled. Family Ulvaceae Enteromorpha chaetomorphoides Borgesen. Entangled in other algae on the floating dock at Paul’s Fish Camp, sta. 13, November, 1972. This species is apparently a tropical Enteromorpha. Enteromorpha clathrata (Roth) J. Agardh. One of the most common and conspicuous of the green algae on a variety of substrates at many sta. the yr around, but best developed during winter and spring. Enteromorpha compressa (L.) Greville. Recorded only at sta. 13 in the river in No- vember and December, 1972, on pilings and the floating dock. Enteromorpha erecta (Lyngbye) J. Agardh. A common and often abundant species, especially at sta. 10, December to February, on a variety of substrates, mostly intertidal. Plants attached to limestone rocks at station 10 were trimmed to 1 cm height in late 218 FLORIDA SCIENTIST [Vol. 39 January and placed in the upper, mid, and lower intertidal levels. After 2 wk, the upper intertidal plants had grown an av of 9.6 mm per day; those at mid-tide 15.4 mm per day; those near low tide 10.1 mm per day. At sta. 5, plants treated similarly grew 11.4 mm per day in the mid to upper intertidal level. During February, plants at sta. 10 avg 7.6 mm per day, a time when this species appeared to be declining in abundance throughout the estuary, and many plants were reproductive. Enteromorpha flexuosa (Wulfen) J. Agardh. Abundant from September through February at many sta., especially on small shells in the intertidal zone. Probably present the yr around. At sta. 11 where sea water from a canal was being pumped over a sloping piece of plywood during construction of the power plant, this species formed two con- spicuous bands on each side of a band of mixed algae during winter months. Enteromorpha intestinalis (L.) Link. Occasional at sta. 10 from December through April, usually in small clumps. This northern species is absent in the vegetative state during the warmer months. Enteromorpha lingulata J. Agardh. Occasional in the lower intertidal zone from Sep- tember through April, sta. 10 on submerged woodwork and elsewhere on shell fragments, pebbles, limestone rocks. Enteromorpha plumosa Kitzing. Low in the intertidal zone forming a fine turf or fuzz on woodwork, and most abundant during January through March. During winter it colonized plastic strips and concrete blocks placed at sta. 5, 6, 7, 8, and 10. Enteromorpha prolifera (Muller) J. Agardh. Found from January through April only on concrete blocks that had been placed at sta. 8 and 10. Enteromorpha salina Kitzing. Present from September through May at all sta., but most abundant in January on concrete blocks placed at sta. 17, 18, and 19. The var. poly- clados Kiitzing was common in January, 1973, at sta. in the river mouth on a variety of substrates. Monostroma oxyspermum (Kitzing) Doty. Present from November to April on black mangrove aerial roots in the intertidal zone, and larger plants grew on other substrates in the drift. Ulva lactuca L. Rarely found attached in Anclote estuary although it is abundant in Tampa Bay. Large plants occurred in the drift during winter and spring when its growth is most rapid. Order CLADOPHORALES Family Cladophoraceae Chaetomorpha brachygona Harvey. A minor component of the algal mat or mass in protected areas among mangrove roots, where it is apparently always loose. Chaetomorpha gracilis Kitzing. Present as part of the algal mat among the pneumato- phores of black mangroves; occasional in most areas but abundant locally; entangled among drift algae during winter. Cladophora crystallina (Roth) Kitzing. Small plants with main axes about 35 p in diam. were common on scattered shells, oyster bars, and mangrove roots the year around. They colonized plastic strips at sta. 5 and 8 during spring and winter. Cladophora delicatula Montagne. On a wide variety of substrates at nearly all sta. the yr around and also on the drift algae. Cladophora repens (J. Agardh) Harvey. Forming a thin mat in the intertidal zone under mangroves at sta. 8 and 9, apparently yr around. Rhizoclonium kochianum Kiutzing, var. kerneri Kitzing. Common on a variety of substrates on and around oyster bars (sta. 10 and 13), on mangrove roots (sta. 14), and entangled in the drift algae. Colonizing plastic strips placed at sta. 5 and concrete blocks at sta. 10. Yr around. No. 4, 1976] HAMM AND HUMM—BENTHIC ALGAE 219 Rhizoclonium riparium (Roth) Harvey. Yr around on nearly all substrates at most stations, but most abundant on mangrove roots and on intertidal muddy sand under man- groves where it was a major constituent of the algal mat. The cells were 2-3 diam. long during summer and fall, 1-2 diam. long during the cooler months. Rhizoclonium tortuosum Kitzing. Occasional on or among black mangrove roots at sta. 8 and 9 the yr around. Order SIPHONOCLADIALES Family Dasycladaceae Batophora oerstedi J. Agardh. Abundant along the north edge of a cove at sta. 16 near low tide line and below on mangrove roots, wood, shells, or shell fragments during the spring. Family Valoniaceae Cladophoropsis membranacea (C. Agardh) Borgesen. On and among the pneumato- phores of black mangroves, especially on the outmost band of roots, at sta. 5, 7, 8, and 25-27. During the winter months the plants appeared to degenerate but did not dis- appear. Anadyomene stellata (Wulfen) C. Agardh. Occasional as an epiphyte of large plants in the drift, especially Digenia, during winter. Order SIPHONALES Family Derbesiaceae Derbesia vaucheriaeformis (Harvey) J. Agardh. At sta. 10 and 13 in December, 1972, on pilings, oysters, other shells, and stones or shell fragments on intertidal protected beaches and below. Family Caulerpaceae Caulerpa ashmeadii Harvey. Common in seagrass beds over a major part of Anclote Anchorage the yr around and in the drift during winter. Caulerpa cupressoides (West) C. Agardh, var. turneri Weber-van Bosse. Occasional in the drift in March, 1974, but not found attached in Anclote estuary. Caulerpa mexicana (Sonder) J. Agardh. Among the drifting algae but not found attached. Caulerpa prolifera (Forsskal) Lamouroux. Present the yr around on seagrass beds in Anclote Anchorage but not as common as C. ashmeadii. Family Codiaceae Boodleopsis pusilla (Collins) Taylor, Joly, and Bernatowicz. Plants forming a fine turf in unconsolidated muddy-sand sediments in protected areas of the intertidal zone under mangrove thickets. Best development occurred among black mangrove aerial roots during fall and winter at sta. 4, 7, and 8, but patches were also found on an oyster bar at sta. 13 and among scattered shells at sta. 20-22. Mats of Boodleopsis tend to accumulate fine sediments. Codium isthmocladum Vickers. Occasional in the drift during the winter of 1973-74, but not found the previous yr. Halimeda incrassata (Ellis) Lamouroux. Common the yr around on seagrass beds throughout Anclote Anchorage growing upon unconsolidated sediments and spreading by elongating rhizoids under the sediments that give rise at intervals to erect branches. On September 19, 1973, several reproductive plants were found near Bailey’s Bluff. The 220 FLORIDA SCIENTIST [Vol. 39 gametangia were 150-225 uw in diameter, 300-485 yw long, obovoid to pyriform, on long, dichotomously-branched pedicels in dense clusters. By September 27, all reproductive plants had lost the gametangia and were dead and decomposing. Penicillus capitatus Lamarck. Common the year around in Thalassia-Syringodium beds throughout Anclote Anchorage, the plants in dense and tall seagrasses often exceed- ing 20 cm tall. Penicillus lamourouxii Decaisne. Plants having the same distribution as P. capitatus but taller and with a less dense capitulum; probably less abundant. Udotea conglutinata (Ellis and Solander) Lamouroux. Having essentially the same distribution as Halimeda and Penicillus though perhaps somewhat less abundant. XANTHOPHYTA Order HETEROSIPHONALES Family Vaucheriaceae Vaucheria bermudensis Taylor and Bernatowicz. Dense mats of this alga occurred in the intertidal zone at sta. 13 and 15 from late fall until spring. Vaucheria thuretii Woronin. Plants forming dense turf or mats low in the intertidal zone were present from September to May at sta. 8. DISTRIBUTION ACCORDING TO SUBSTRATE—In connection with field work, the type of substrate upon which each species was growing was recorded for 10 dif- ferent types and also the loose, drifting algae that continue to grow until they wash ashore or are swept out to sea. Table 1 lists all species recorded and the substrata upon which each occurred. Epiphytes are listed with the substrate upon which their host was growing. TABLE 1. Species list by habitat or substrate type: A= Unconsolidated sediments, sublittoral G = Mangrove roots B= Spartina stems H = Pilings and other submerged C= Scattered shells structures D= Intertidal mud and sand I= Concrete blocks E= Limestone rocks J= Plastic strips F = Oyster bars K= Loose and drifting AOPOB ve DD: EB. BE 3G Teil J K Acanthophora spicifera X X Acrochaetium sagraeanum X > Sieg) X xX A. sargassi X A. thuretii X Agmenellum quadruplicatum X A. thermale xX X X X X X Anacystis aeruginosa X X X XX A. dimidiata xX A. marina X Anadyomene stellata xX Bachelotia antillarum xX XO) Xe X X Batophora oerstedi X X XX Boodleopsis pusilla X X Ko eX No. 4, 1976] HAMM AND HUMM—BENTHIC ALGAE 221 TaBLE 1. Species list (continued) Bostrychia moritziana B. radicans X B. scorpioides B. tennela Callithamnion byssoides Caloglossa leprieurii Calothrix crustacea Xs X Caulerpa ashmeadii X C. cupressoides C. mexicana C. prolifera X Centroceras clavulatum X X X Ceramium byssoideum >), ed: Gh WE’ C. corniculatum C. fastigiatum X Chaetomorpha brachygona X C. gracilis X Chondria baileyana C. collinsiana C. leptacremon C. littoralis X C. tenuissima X Cladophora crystalline X X X C. delicatula X C. repens Cladophoropsis membranacea Cladosiphon occidentalis X Codium isthomcladum Dasya pedicellata Derbesia vaucheriaeformis X X X X Dictyota dichotoma Digenia simplex Diplochaete solitaria Ectocarpus elachistaeformis E. intermedius E. siliculosus Enteromorpha chaetomorphoides E. clathrata X E. compressa E. erecta E. flexuosa X E. intestinalis E. lingulata X X E. plumosa E. prolifera E. salina X Xa XX Entocladia viridis Entophysalis conferta X E. deusta Erythrocladia subintegra Erythrotrichia carnea », cea, 4 > a. Fosliella atlantica xX F. farinosa Giffordia conifera xX x xX G. mitchelliae Grex XO XG Xe EXE POX XC G. rallsiae x xX xX ~ rx | OO ~ x x x MX ~ AH MM KR OM ~ x ~ ~ ~ KX ~ ~ ~ ~ A Kem x KM ~xK~KM KM KK Ame ~K~ KM KK KKK OM KKK KKM KM OM x~ KK KM ~ xX ~~ ~ ~~ KK KM 222 FLORIDA SCIENTIST [Vol. 39 TABLE 1. Species list (continued) > oe) @ ) 9) hry ?) on a A Goniotrichum alsidii X X », Ge Be. Graaciilaria foliifera xX G. verrucosa Halimeda incrassata X Halymenia floresia Herposiphonia secunda X xX H. tenella X X xX Hypnea musciformis H. spinella Jania adherens J. capillacea Johannesbaptistia pellucida X X Laurencia intricata L. obtusa X L. poitei Lophosiphonia cristata L. saccorhiza X Mastigocoleus testarum Microcoleus lyngbyaceus X XxX Monostroma oxyspermum Murrayella periclados Myriotrichia subcorymbosa Nodularia harveyana Penicillus capitatus P. lamourouxii Phaeophila dendroides X Polysiphonia echinata P. havanensis X P. hemisphaerica X P. subtilissima Porphyrosiphon notarisii X Rhizoclonium kochianum R. riparium X X R. tortuosum Sargassum filipendula S. fluitans S. hystrix var. buxifolium S. natans S. pteropleuron Schizothrix arenaria S. calcicola XX S. mexicana Scytonema hofmanni X Solieria tenera X Sphacelaria furcigera X X X X Spirulina subsalsa X Spyridia filamentosa xX X. we Stictyosiphon subsimplex Udotea conglutinata X Ulva lactuca Ulvella lens X Vaucheria bermudensis V. thuretii X KX a a a ~ x ~~ XX ~ KH KM KM ~ ~ mx mM ~ x ~ xX ~*~ X xx KM ~ ~ x rv ~~ *K xxx OM ~ ~ xX ~ x mx xX ~ x ~~ ~ x * ~ KKK a a a os ee ~ x ~ No. 4, 1976] HAMM AND HUMM—BENTHIC ALGAE pipes, Unconsolidated Sublittoral Sediments: The most extensive substrate of the Anclote estuary, about 30 sq km, is in the form of unconsolidated sediments be- low the intertidal zone. About 40% of this area, 12 sq km, is covered by seagrass beds made up of 4 species: Syringodium filiforme Kitzing (manatee grass), Thalassia testudinum Konig (turtle grass), Halodule wrightii Ascherson (shoal grass), and Halophila engelmannii Ascherson (no common name), in that order of abundance (Zimmerman et al., 1972, 1973). Shoal grass has been reported also as Diplanthera wrightii (Ascherson) Ascherson in the literature. An estimate of the area occupied by seagrasses in Anclote estuary was obtained by aerial pho- tography (Feigl and Pyle, 1973). While most benthic algae require some kind of solid substrate for attach- ment, there are a few species capable of developing upon unconsolidated sedi- ments similar to land plants and seagrasses. Unique among benthic algae for the ability to anchor themselves upon unconsolidated sediments are certain genera of the order Siphonales of the green algae, an order that seems to us to be as highly evolved as the flowering plants. Representatives of this group (8 species) made up 62% total recorded on bottom sediments below the intertidal zone. Another group adapted to grow exclusively on this type of substrate is the family _ Vaucheriaceae of the Xanthophyta, although most stands of these are in the inter- tidal zone. One species, however, was found below low tide. The bluegreen algae are a third group capable of growing upon sediments, but for different reasons. Though usually not attached, both coccoid and fila- mentous species occur among sand grains near the surface or they form a thin film on the surface where the prevailing turbulence of the water is low. Four such species were found in Anclote estuary. Spartina Stems: There is a characteristic benthic algal flora upon and around the bases of the stems of salt marsh plants such as Spartina (Blum, 1968). In the Anclote estuary 11 species were recorded: 5 bluegreens, 45%; 3 reds, 27%; 2 greens, 18%; and, brown, 9%. Predominance of bluegreens in a salt marsh was noted by Webber (1967) in Massachusetts. The two most common bluegreens at the base of Spartina were Calothrix crustacea and Entophysalis deusta. The red algae Erythrotrichia carnea and Lophosiphonia saccorhiza were common; and Bostrichia radicans was present but rare. These species were yr around, but the one species of brown alga found on Spartina, Giffordia mitchelliae, was seasonal, but when present (April and May, 1973), exceeded all others in biomass. Scattered Shells: Living and dead mollusc shells in the intertidal zone and below are an important attachment surface for algae in the Anclote estuary be- cause of the scarcity of rocks; 37 species were found on shells. Red algae were predominant, making up 30% of the species, the greens 27%, bluegreens 24%, and browns 19%. Of the bluegreens recorded, 3 species were boring into shells: Schizothrix calcicola, Entophysalis deusta, and Mastigocoleus testarum listed in order of abundance. The first was found in 100% of the shells examined, the second in 75%, the third only in old, dead shells. These algae probably promote the gradual fragmentation and decomposition of shells. 224 FLORIDA SCIENTIST [Vol. 39 Of 7 species of brown algae found on shells, only Giffordia mitchelliae was present the yr around. All others were found only during winter and spring. Of the 11 species of red algae, all were yr around although many were best de- veloped during spring. Intertidal Sediments: Protected, low-energy beaches supported a greater variety of algae than exposed beaches, especially where there were aerial roots of black mangroves. Bluegreen and green algae each accounted for 33% (10 species) of the total; there were 5 species of red algae, 17%; 3 browns, 10%; and 2 species of Vaucheria (Xanthophyta), 7%. Although certain bluegreens, plus Vau- cheria and Boodleopsis, are adapted to grow on intertidal beaches, many other genera are not but were present because of protection afforded by dense stands of black mangrove aerial roots and the tendency to form algal mats that are not readily dislodged. On a protected beach, some algae are able to stay in place even though they are attached only to a small shell fragment or large sand grain. Unless this fact is taken into consideration, the ratios among 4 major groups on intertidal sand would be misleading. Limestone Rocks: The red, brown, and green algae comprising 22 species on limestone rocks, were equally represented with 6 species each or 27%, the blue- greens with 4 species or 18%. This type of substrate is scarce in the Anclote es- tuary, and most natural rocks are in the intertidal zone where many algal species cannot grow and where competition for space is greater from oysters and barna- cles than it is below low tide. Oyster Bars: Among the 33 species found on oyster bars, the green algae were predominant with 11 species (36%), 5 belonging to Enteromorpha. Bluegreen, red, and brown algae were about equal in numbers of species and there was one xanthophyte. Oyster bars are mostly intertidal and do not permit colonization of most species that require constant submergence. Vaucheria bermudensis grew on soft sediments among oyster shells and over them to some extent. Myriotrichia subcorymbosa was an epiphyte of larger algae on the oyster bars. Rhodes (1970), in a study of algae of an oyster bar on the Eastern Shore of Virginia both summer and winter, found 43 species of which 65% were red algae, 21% browns, and only 14% were greens. He omitted bluegreens. His area, however, was of uniformly higher salinity than the Anclote river mouth. Mangrove Roots: Of 38 species recorded from mangrove roots, 15 were greens (39%), 11 were reds (29%), 9 were bluegreens (24%), and 3 were browns (8%). In tropical and subtropical waters, few species of brown algae grow in the inter- tidal zone. The high percentage of green algae in this habitat was not because of Enteromorpha as on oyster bars, but because of Cladophoraceae with 3 genera represented. Enteromorpha does not do well in the shade. Two types of mangrove roots are found in the intertidal zone in Anclote estu- ary, both in abundance: the pencil-like pneumatophores of the black mangrove, Avicennia germinans (L.) L. and the arching prop roots of the red mangrove, Rhizophora mangle L. Each provides a habitat that is somewhat different and the algal communities differ mainly in the proportion of species present rather than a qualitative difference. Roots of both species are mostly shaded by the trees No. 4, 1976] HAMM AND HUMM—BENTHIC ALGAE 225 but, in the case of black mangroves, rows of pneumatophores often extend out beyond the canopy where they receive full sunlight at least part of the day. Mangrove roots support a characteristic algal community that has been in- tensively studied by Post (1963) and referred to by her as a BosTRICHIETUM in allusion to the dominance of species of the strictly intertidal genus Bostrichia. Four species of this genus and two varieties colonize the mangrove roots in the Anclote estuary, along with their common associates Caloglossa and Murray- ella. Catenella, a component of the BosTricHIETUM in south Florida was not found at Anclote. The most abundant green alga on and among mangrove roots was Clado- phoropsis membranacea. At sta. 7 and 8 it grew attached to almost all the pneu- matophores and formed dense cushions of coarse filaments between them in the outer m of the root fringe where light was most intense. Mangrove roots more ex- posed to wave action supported fewer algal species, but during the cooler months the proportion of green algae was higher, especially abundant were Monostroma oxyspermum and Enteromorpha erecta. In March these were re- placed by 3 species of filamentous brown algae until mid-May: Ectocarpus inter- medius. E. siliculosus, and Giffordia mitchelliae. From late May and throughout the summer, this area was colonized only by bluegreens. Rehm (1973), in a study of the algae of prop roots of red mangroves around the Florida coast, recorded 73 species of which 40% were greens, 51% reds, 5% browns, and 4% bluegreens. His work included the Florida Keys where man- groves grow in clear, highly saline water and algal diversity is high. Pilings and Other Submerged Structures: Included here are all forms of sub- merged wood, buoys, tin cans, tires, and the rock breakwaters at Howard Park where 40 species were recorded upon them; 15 were red algae (38%), 12 were greens (30%), 8 were bluegreens (20%) and 5 were browns (12%). The 12 green algae included 8 species of Enteromorpha. Of the 5 brown algae, only Giffordia mitchelliae was yr around, the others restricted to winter and spring. Concrete Blocks: Concrete blocks and polyethylene plastic strips were placed at 12 sta in order to determine the season of colonization of some species, to ob- tain an estimate of growth rates of Enteromorpha, and to provide a new surface for attachment by species that might otherwise be missed, especially small species that would be evident on the plastic strips. Concrete blocks were placed on December 12, 1972, and August 23, 1973, and examined at weekly or bi- weekly intervals. Colonization of the blocks required 5 wk during December-January. On January 19, pieces were chipped off, examined in the laboratory, and 10 species identified. A wk later 7 additional species were found. These 17 were the princi- pal constituents of the winter-spring seasonal flora of the estuary. After 15 wk (March 27, 1973), the previously-abundant species of Enteromorpha, had de- clined, filamentous brown algae had become predominant, and 4 additional species were recorded. During April and May the winter-spring flora on the blocks declined and disappeared and was replaced by a variety of bluegreens, the only algae on the blocks during the summer. Blocks set out in August were 226 FLORIDA SCIENTIST [Vol. 39 colonized faster, but initially only by green and bluegreen species. They were replaced or overgrown by the winter-spring flora beginning in November. During the second yr, algal colonization on the blocks was less dense, ap- parently because of the development of many barnacles and oysters, but the pattern was the same, and additional species were found bringing the total to 42. Three species were found only on concrete blocks: Acrochaetium thuretii, Chondria collinsiana, and Enteromorpha prolifera. Plastic Strips: Clear plastic strips were placed in the environment so that the substrate could be placed under a microscope to observe microscopic or very small species in situ. Strips 30 X 3 cm were put out on February 9, 1973, at the same stations as the concrete blocks. They were weighted at one end and allowed to trail in the water. After 4 wk, 2 brown algae, Myriotrichia subcorymbosa and Stictyosiphon subsimplex, and a bluegreen, Calothrix crustacea were present in abundance. After 6 wk 7 more species were present. Ultimately, 26 species were identified that were rather evenly distributed among the 4 major groups. There were 6 each of bluegreens, reds, and browns, and 8 greens. All species on the strips were found on other substrates as well. Drift Algae: Anclote estuary is an area where masses of loose and drifting algae can occur for long periods of time and continue to grow. The water is shallow enough for light penetration and the currents weak enough so that the drifting masses are only occasionally washed ashore or swept out to sea. Drift algae occur in greatest abundance from October to April, with a peak in the spring. Apparently northerly winds favor the accumulation of loose plants and large quantities tend to move into Anclote Anchorage from the Gulf of Mex- ico. The species are those characteristic of the open Gulf rather than of the estu- ary, and the biomass of the standing crop in the estuary is inadequate to account for the quantities found in the drift. A sample of drift algae that covered an area 0.5 X 1 m was collected and analyzed for algal species and associated fauna. Three small fish and a large blue crab were seen to escape when the mass was netted. Wet wt of the mass was 2494 g, of which 60 g were animals. The 2434 g of algae had a dry wt of 240 g. Most of the animals were crustaceans, but there were also tunicates, bryozoans, anne- lids, molluscs, and fish. During winter months, 2 species of red algae made up about 90% of the drift: Laurencia obtusa (about 50%) and L. poitei (30 to 45%). The red alga, Digenia simplex, and several species of Sargassum often made up 5% of the drift. Including epiphytes, 65 species were found in the drift. Of these, 32 were red algae (49%), 15 were greens (23%), 13 were browns (20%), and 5 were blue- greens (8%). Most of the bluegreens were epiphytes. Percentages on Substrates: Table 2 indicates the relative adaptation of species of each major group in Anclote estuary for attachment to the 10 substrates that were recognized. Bluegreen algae colonized the bases of Spartina stems more than any other group and made up 45% of the species found there. The red algae made up nearly 50% of species present in the drift, mainly species that had origi- nally grown upon some substrate in the open Gulf of Mexico and after breaking No. 4, 1976] HAMM AND HUMM—BENTHIC ALGAE 227 TaBLe 2. Percentage of the species of each of the major groups of benthic algae found on 10 different substrates or in the drift in Anclote estuary, 1972-74. Substrates are listed in decreasing order of occupancy by the species. CYANOPHYTA % RHODOPHYTA % Spartina stems 45 Drifting 49 Intertidal sediments 33 Pilings, etc. 38 Bottom sediments 31 Concrete blocks 36 Scattered shells 24 Scattered shells 30 Mangrove roots 24 Mangrove roots 29 Plastic strips 23 Limestone rocks 27 Oyster bars 21 Spartina stems 27 Pilings, etc. 20 Plastic strips 23 Limestone rocks 19 Oyster bars 18 Concrete blocks 16 Intertidal sediments 17 Drifting 8 Bottom sediments 0 PHAEOPHYTA % CHLOROPHYTA % Limestone rocks 27 Bottom sediments 62 Oyster bars 24 Mangrove roots 39 Plastic strips 23 Intertidal sediments 33 Drifting 20 Oyster bars 33 Concrete blocks 19 Plastic strips 31 Scattered shells 19 Pilings, etc. 30 Pilings, etc. 12 Concrete blocks 29 Intertidal sediments 10 Limestone rocks Qi Spartina stems 9 Scattered shells 27 Mangrove roots 8 Drifting 23 Bottom sediments 0 Spartina stems 18 loose drifted into the estuary. Brown algae made up a larger proportion of spe- cies found on limestone rocks than on any other substrate, but they were also well represented on oyster bars and plastic strips during the cooler months. The green algae accounted for 62% of species colonizing subtidal bottom sediments because of the abundance of members of the Siphonales, but they were also well represented on intertidal mangrove roots, especially the Ulvaceae and Cla- dophoraceae. Discusston—The algal population of the Anclote estuary is that of an area of fluctuating but relatively high salinity consisting of species that are moderately to highly euryhaline. During winter and spring, the dry season in Florida, there are more species present that are sensitive to salinity fluctuations, as there is greater stability than during summer and fall. Geographically, the flora is closely allied to that of the coastline of North and South Carolina, an area occupied by species of tropical affinities during the warmer months and by species of north temperate affinities during the cooler months. Within the Gulf of Mexico, the Anclote estuary is at the southern margin of Earle’s (1969) subregion C, Apalachicola to Anclote Keys, and at the northern edge of her subregion D, Tampa Bay to Cape Romano. Although just north of the 228 FLORIDA SCIENTIST [Vol. 39 latter, the Anclote estuary is more closely related to subregion D than to C be- cause of its shoreline of barrier islands and bottom characteristics. In her treat- ment of the entire Gulf of Mexico, Earle (1972) recognized the coastline from Port St. Joe to Cape Romano as “area E” in which the Anclote estuary is at the center. A total of 122 species were recorded in our study. In addition to these, Bal- lantine and Humm (1975) list 15 found only on seagrass leaves. This brings the total benthic algal flora of Anclote estuary to 136. Earle indicates that a total. of 351 species had been recorded in her “area E” of the Florida Gulf coast to 1972. Thus the Anclote estuary supports about 36% of all species known for the Florida Gulf coast between Port St. Joe and Cape Romano. If comparisons of each of the 5 major groups are made, the Anclote area supports 67% of the blue- greens, 45% of the greens, 39% of the browns, and 33% of the reds. The high per- centage of bluegreen algae in Anclote estuary is accounted for by the fact that these are typically inshore, estuarine species. The relatively high percentage of green algae is accounted for by the fact that members of two families, Ulvaceae and Cladophoraceae, are also highly tolerant of estuarine conditions and their species constitute nearly half of the green algae known for the Anclote estuary. The relatively high percentage of brown algae in Anclote estuary results from the fact that many species of browns, especially Ectocarpaceae and Chordari- aceae, are winter-spring species that occur in shallow water and become abun- dant in the estuary when the salinity is relatively high and stable. The red algae, with the lowest percentage of any group in the estuary, are to a great extent characteristic of warm, clear water of high and stable salinity like that of the open sea or among the Florida Keys. Relatively few species toler- ate the fluctuating conditions of estuaries. Of the 610 species recorded for the Gulf of Mexico (Earle 1972), only about 22% have been recorded for the Anclote estuary. ACKNOWLEDGMENT—A graduate stipend and expense funds for field work in support of this research were received from the Florida Power Corporation of St. Petersburg. We are grateful to James Schneidmuller for preparation of fig. 1. LITERATURE CITED Aziz, K. M. S. 1965. Acrochaetium and Kylinia in the Southwestern North Atlantic Ocean. Ph. D. dissert. Duke Univ. Durham, N. C. BALLANTINE, D., AND H. J. Humm. 1975. Benthic algae of the Anclote estuary. I. Epiphytes of sea- grass leaves. Florida Sci. 38:150-162. BairD, R. C. (ed.) 1972. Anclote Environmental Project Report for 1971. Dept. Marine Sci. Univ. S. Florida. 251 pp. (Mimeographed) . 1973. Anclote Environmental Project Report for 1972. Dept. Marine Sci. Univ. S. Florida. 219 pp. (Mimeographed) . 1974. Anclote Environmental Project Report for 1973. Dept. Marine Sci. Univ. S. Flor- ida. 136 pp. (Mimeographed) BLuM, J. L. 1968. Salt marsh Spartinas and associated algae. Ecol. Monogr. 38:199-221. Dawes, C. J. 1974. Marine Algae of the West Coast of Florida. Univ. Miami Press. Coral Gables. DrovET, F. 1968. Revision of the Classification of the Oscillatoriaceae. Acad. Nat. Sci. Philadelphia Monogr. 15. No. 4, 1976] HAMM AND HUMM—BENTHIC ALGAE 229 . 1973. Revision of the Nostocaceae with Cylindrical Trichomes. Hafner Publ. Co. New York. , AND W. A. Daly. 1956. Revision of the coccoid Myxophyceae. Butler Univ. Bot. Stud. 12:1-218. Ear Le, S. 1969. Phaeophyta of the eastern Gulf of Mexico. Phycologia 7:71-254. . 1972. Benthic algae and seagrasses. Folio 22:15-18; pl. 6. In BusHNELL, V. C. (ed.) Serial Atlas of the Marine Environment. Amer. Geogr. Soc. New York. FEIcL, J. L., anp T. E. Pyte. 1973. Application of aerial photography to the study of seagrass beds and turbidity in a Florida estuary. Appendix 3B:199-204. In Anclote Environmental Report for 1972. Dept. Marine Sci. Univ. S. Florida. (Mimeographed) Fiore, J. 1970. Life History Studies of Phaeophyta from the Atlantic Coast of the United States. Ph. D. dissert. Duke Univ. Durham, N. C. Hum, H. J. 1971. Anclote Environmental Project Report for 1970. Dept. Marine Sci. Univ. S. Flor- ida. 172 pp. (Mimeographed) , AND D. Hamm. 1976. New records and range extensions of benthic algae in the Gulf of Mexico. Florida Sci. 39:42-45. Post, E. 1963. Zur Verbreitung und Okologia der Bostrich-Caloglossa Assoziation. Internat. Rev. Gessamten Hydrobiol. 48:47-152. RexM, A. 1974. A Study of the Marine Algae Epiphytic on the Prop Roots of Rhizophora mangle L. from Tampa to Key Largo, Florida. Ph. D. dissert. Univ. S. Florida. Tampa. Ruopes, R. G. 1970. Seasonal occurrence of marine algae on an oyster reef in Burton’s Bay, Virginia. Chesapeake Sci. 11:61-71. RUENESS, J. 1973. Speciation in Polysiphonia in view of hybridization experiments: P. hemisphaerica and P. boldii. Phycologia 12:107-109. WesseR, E. E. 1967. Bluegreen algae from a Massachusetts salt marsh. Bull Torrey Bot. Club 94: 99-106. Wynne, M. J., AND P. Epwarps. 1970. Polysiphonia boldii sp. nov. from Texas. Phycologia 9:11-16. ZIMMERMAN, R. J., R. A. Dietz, T. E. PYLe, S. W. Rocers, N. J. BLAKE, AND H. J. Hum. 1973. Ben- thic community—seagrasses. pp. 115-141. In Anclote Environmental Report for 1972. Dept. Marine Sci. Univ. S. Florida. (Mimeographed) Florida Sci. 39(4): 209-229. 1976. Errata: In Florida Scientist 39(3), the following corrections are noted: page 191, line 11 for 400 psig read 40 psig; page 191, line 20 for at least 50% read at least 60%; page 196, line 24 for 120 psi read 1200 psi. 230 FLORIDA SCIENTIST [Vol. 39 Biological Sciences VEGETATION OF SOUTHEASTERN FLORIDA~—I. PINE JOG DANIEL F. AUSTIN Department of Biological Sciences, Florida Atlantic University, Boca Raton, Florida 33432 ABSTRACT: Historical documents, aerial photography and on-site studies have been used to docu- ment vegetation changes on the quarter-section where Pine Jog Environmental Sciences Center is located. Data indicate that the entire Pine Jog region is undergoing secondary succession. All analy- ses show that the original vegetation was wet prairie, marsh and low hammock. Due to lowering of the water table by drainage, many of the wet prairies have changed to pine flatwoods. Frequent burn- ing shortly after the turn of the century reduced diversity in the remaining wet prairies and marshes. The disturbance caused by drainage and fires has enhanced invasion by exotic plants, particularly Schinus terebinthifolius and Melaleuca quinquenervia. In FLoripa as elsewhere, vegetation patterns are largely controlled by physi- cal features. Davis (1943) and others have pointed out the close correlations be- tween hydrology, soil types, elevations and plant communities. Because of these interrelations any changes in the physical factors may greatly alter community structure. A factor that is at times even more important than the physical fea- tures is manipulation by man (Alexander, 1958; Austin and Weise, 1973). Some apparently harmless events may have long-range effects on the habitats (Austin, 1976). The following report is the first of several sites studied to determine how the major communities of southeastern Florida have changed in the past few decades. Once the data for the communities are compiled we will have a better understanding of secondary succession which is poorly understood at present (Alexander and Crook, 1974). History—Pine Jog Environmental Sciences Center, now affiliated with Flor- ida Atlantic University, is located in the S. E. quarter of Section 3, Township 44S, Range 42E, west of the city of West Palm Beach. Henry M. Flagler was the first owner, obtaining the land shortly after 1893 when he made his first land purchase on Lake Worth and established West Palm Beach. For several years land including Pine Jog was held by Flagler’s company, the Model Land Com- pany. In March of 1929 land now including Pine Jog was offered for sale at the West Palm Beach Court House, and the Lake Worth Drainage District took con- trol of the land in May of 1930. Between the time it was purchased in 1930 and the next time it changed owners, the land was occupied by a few “squatters” but there were apparently no permanent dwellings. The area around Pine Jog was “open” between the 1920’s and 1940’s, and various farm plots were pre- pared without regard to ownership (Klein, personal communication). The main crops of that time were squash, tomatoes and peppers. A substantial difficulty with farming during this period was fire. Palm Beach County was open range and had numerous semi-wild cattle. Because of this the cattlemen periodically burned hundreds of acres. These annual or perhaps more No. 4, 1976] AUSTIN—VEGETATION OF PINE JOG 231 frequent fires were designed to stimulate new tender forage for the cattle by releasing nutrients and reducing competition. The fires and the cattle had con- siderable effect on the natural vegetation and on the scattered farms. Mr. and Mrs. Alfred G. Kay purchased the quarter-section now including Pine Jog in April of 1946. The Kays, after numerous discussions with John Storer, David Fairchild, Marston Bates, and others, decided to provide the area with an environmental center. Early in 1960 Pine Jog was established as a conservation education center. Since it was purchased in 1946 by the Kays, the land has been protected from fire. Farming has been eliminated from the Center property since at least the early 1950's. The quarter section is now owned by the Kays, the State of Florida and Milton Klein, in order of size of land holdings. PHysiocGRaPHY—As in much of southern Florida, the relief on the Pine Jog property is slight (U.S.D.A., 1967). Elevations range from a 15 ft m.s.1. low in the marsh to a high of 18 ft in the hammock. Scattered through the property are ponded areas where the elevations are mostly near 16 ft; some of these dip to 15 ft. The “ridges” between these ponds are mostly 17 ft or slightly more. Some ponded areas have Basinger-Myakka soils (U.S.D.A., 1946, 1973). These are low soils, seasonally flooded, usually white or light grey in color and extend- ing down six feet or more to rock. The ponded marsh is Placid soil with a thin muck layer of up to 1-2 ft; below this is white or yellow sand supported by a shell- rock layer 6-10 ft below the surface. On the higher ridges the soils are Basinger. These soils are similar to the ponded Basinger-Myakka series, but have a darker color and shellrock within about 6 ft of the surface. Moreover, there is often a weakly cemented hardpan in Basinger soils. The Pine Jog property lies within a shallow drainage basin between the major systems of the Loxahatchee Slough on the west and the Lake Osborne Basin to the east. Since the ridges on both sides of the Pine Jog Basin direct water flow, much of the local surface runoff and water from farther north originally flowed south through the area. Drainage in this part of the state began as early as the 1870's when former Lieutenant Governor W. H. Gleason started canals on Lake Worth. The first effective drainage, however, occurred in the first years of the 1900's. During that time several canals were finished from Lake Okeechobee to the ocean. The ca- nals included the Miami Canal, the North New River Canal and the South New River Canal finished in 1912, and the Palm Beach Canal finished in 1917. The Palm Beach Canal was enlarged during the 1920's, in part to provide fill for Con- nor s Highway. Before the Palm Beach Canal was opened water was high enough in Lake Clarke east of Pine Jog that Seminoles came along the marsh edge to a trading post near what is now Dreher Park (T. T. Sturrock, personal communi- cation). Enough water was removed when the canal opened that the Indians could not use their canoes on the old lake route. Before the reduction of the water table through drainage (Parker, 1974) the water table in the region was at least 6 ft higher (Thomas, 1974). 232 FLORIDA SCIENTIST [Vol. 39 VEGETATION—Several documents indicate the past and present patterns of plant communities on Pine Jog. The earliest reports were made by MacKay (1845) who surveyed the township and range boundaries, and Reyes (1858) who laid out the section lines. Klein (personal communication) has pointed out sev- eral features that he remembers have changed since the 1930’s. Aerial photog- raphy (U.S.D.A., 1940), and soils maps (U.S.D.A., 1946) are consistent with the earlier reports. Plant community names used here follow Davis (1943). Original Associations: All of the early materials show that Pine Jog was low wetland from the late 1800's to as late as 1940 (MacKay, 1845; U.S.D.A., 1940, 1946). Between 1900 and 1929 the pine trees were harvested in the area sur- rounding Pine Jog. Following this harvesting there were annual fires and by 1934 there were few pine seedlings on the property over | m tall (Klein, personal com- munication). The present ponded prairies were termed in the 1930's “cypress bottoms.” This term historically has been used for wet prairies dominated by sand cypress or Hypericum fasciculatum. The present marsh has been similar in size and shape since before the year 1900, but before drainage there were two other marshes (Fig. 1). As late as 1940 (U.S.D.A., 1940) most of the ridges between the ponded prairies and marshes were also wet prairies. By 1940 pines had grown to several ft in a few areas, but most of the quarter-section was still wet prairie. Prior to this date all of the ridged land was covered by a wet prairie community. Ponded Wet Prairie ape Wet Prairie = Marsh Low Hammock Pd ofces Fig. 1. Detail of plant associations on the Pine Jog property about the year 1900. Interpreted from 1940, 1965 and 1973 aerial photography. No. 4, 1976] AUSTIN—VEGETATION OF PINE JOG 233 The low hammock was similar in shape in the 1940’s, but with smaller oaks (Quercus virginiana) and cabbage palms (Sabal palmetto). This habitat is not indicated in the 1800 reports and may have developed since the turn of the cen- tury. Fires in the early 1900's may also have been responsible for altering the hammock in the 1940 photography. Ponded wet prairies were only slightly different from the other prairies be- fore drainage. The largest difference was the abundance of Hypericum fascicu- latum and Stillingia aquatica in the ponded prairies and the reduced density of these species in the ridged prairies. There were three communities on the prop- erty before drainage: wet prairie, marsh and low hammock. Present Associations: All of the plant associations at Pine Jog are now in dif- ferent stages of secondary succession. Two of the original marshes have been all but obliterated by drainage, excessive burning and farming. These processes did not change the third marsh as drastically, probably because it was lower than the others and retained more water. A pond was dug in the third marsh in 1967 and enlarged in the Spring of 1974. Several native plants were introduced to the pond margins in order to stabilize the soil more rapidly. Thirty percent of the 175 species now found on the property are marsh plants. While the low hammock has recently decreased in size, it still contains many of the plant species originally present. Eight percent of the species present in Pine Jog are found in the hammock. The wet prairies are the most altered community on the property. Since the period of drainage and fires, pines have invaded from the northeast and north- west. These pines were beginning to become established in the 1930’s when they were seedlings (Klein, personal communication). Seventeen percent of the Pine Jog flora is found in the pine flatwoods. From all available data, the pine flat- woods areas now on Pine Jog are less than 40 yr old (Fig. 2). Another indicator that the vegetation of the Pine Jog area was originally prai- rie is the presence of scattered cypress, Taxodium distichum. Several other wet prairie systems in the county, such as Corbett Conservation Area, include cy- press heads and scattered individuals or clumps of cypress trees. Were it not for parallel cases, the Taxodium at Pine Jog would appear anomalous. Before it was bulldozed in late 1974, there was a fairly large cypress head north of the Palm Beach Canal. This head was only about 2 miles from Pine Jog. Without doubt the south-flowing water during wet seasons and storms carried Taxodium seeds and fruits into Pine Jog. The previously wet prairie margins and marshes were suit- able habitat for the cypress to germinate. Ponded wet prairies have experienced two changes in the past 70 yr. First, the frequent fires between the 1920’s and 1946 decreased total floristic diversity. Many wet prairie species were totally eliminated from several ponded prairies. This is the major reason that only 10% of the plants on the property are wet prairie species. In many sites it is still possible to walk on totally barren pond bottoms. The margins of these ponds retain a few wet prairie species such as Fuirena scirpoidea, Lachnanthes caroliniana, Syngonanthus flavidulus, and scattered Xyris sp. Furthermore, the majority of these ponds are fringed by lines 234 FLORIDA SCIENTIST [Vol. 39 OUD, Fallow Field Pine Flatwoods Marsh 4 Grove Temporary Pond Melaleuca Low Hammock Wet Prairie " ‘ van ae OA 1G a ‘ oy ia x v. a rarer’ ry Ma 500 FEET Fig. 2. Detail of the plant associations and major cultural features of Pine Jog in 1974. Inter- preted from 1965 and 1973 aerial photography. of Chrysobalanus icaco which delimit with some detail the old boundaries. During the past 5 yr, several of these plants have begun to invade the pond bottoms. The second change has been caused by the exotic tree Melaleuca. Exotics: Certainly the most abundant and noticeable exotic plant on the property is Melaleuca quinquenervia. In 1946 there were only six of these trees on the entire tract. Even at that time they were in such demand that they were periodically stolen for landscaping. Since 1946 these trees have reproduced pro- lifically both by seeds and vegetative suckers. In 1973 there were three large Melaleuca copses on the property. Two occupied former marshes degraded to wet prairies; the third had multiplied on the scarified surface of a wet prairie on the southeastern part of the property. Disturbed wet prairie sites are partic- ularly favored by these trees. During the 5 yr that my study has spanned, Mela- leuca has rapidly encroached on some of the other wet prairies. Various other exotic species are among the 35% disturbed site plants but the majority appear to be ephemeral and to compete little with native species. Three, I believe, are noteworthy. The second most frequent exotic tree at Pine Jog is the pepper tree, Schinus terebinthifolius. This tree was first introduced into Florida from Brazil and Para- guay in 1898 and has become widely naturalized since the 1950’s (Alexander and Crook, 1974). At Pine Jog it has invaded the margins of the marsh and dis- turbed sites near buildings. No. 4, 1976] AUSTIN—VEGETATION OF PINE JOG 2395 A plant called Florida elodea, Hydrilla verticillata, was introduced into the state in 1959. Until the artificial pond was enlarged in 1974, there was little prob- lem with this species. Now the population in the pond is increasing rapidly. While it provides some protection for young fish and micro-animals, the large masses of decaying plants usually cause a decrease in dissolved oxygen and lead to decreased productivity. The last exotic to be mentioned has apparently never been reported before in our state: Passiflora foetida. This is a West Indian species and the source of its introduction to Pine Jog remains unknown. Between 1971 and 1973 a single plant was noted on the property. If the plant flowered during this period, no one discovered the blossoms. In the fall of 1974 the first flowers were noted. Later seedlings were found in several sites on the property. Near Christmas of that year, plants were found in fruit 1-1.5 miles south of Pine Jog. The impact this species will have on the native flora cannot be predicted. ACKNOWLEDGMENTS—The staff at Pine Jog, particularly my wife Sandra Aus- tin, as well as Sarah Cass and the Director, Ray M. Iverson, have been most co- operative in helping with this study. Mr. Milton Klein has given me his impres- sions of the property and vegetation since he first saw it in the 1930's. To all of these I extend my thanks. Mr. Donald Vandergrift of the Soil Conservation Of- fice was most helpful in providing copies of unpublished U. S. Department of Agriculture Soil Conservation Service soil maps. This study was supported in part by a grant from the Joint Center for Environmental and Urban Issues. The checklist of plants and more detailed report has been deposited at Pine Jog and the Florida Atlantic University Library. LITERATURE CITED ALEXANDER, T. R. 1958. Ecology of the Pompano Beach Hammock. Quart. J. Florida Acad. Sci. 21: 299-304. , AND A. G. Crook. 1974. Recent vegetational changes in South Florida. In GLEAson, P. J., ed. Environments of South Florida: Present and Past. Mem. Miami Geol. Survey 2:61-72. AusTIN, D. F. 1976. Mangroves as monitors of change in Spanish River. Florida Environm. Urb. Issues 3:4-7; 15-16. AND J. G. Weise. 1972. Annotated checklist of the Boynton Beach Hammock. Quart. J. Florida Acad. Sci. 35:145-154. Davis, J. H. 1943. The natural features of southern Florida. Florida Geol. Bull. 25:6-301. MacKay, G. 1845. United States Survey of Township 44S, Range 42E, Florida. Parker, G. G. 1974. Hydrology of the pre-drainage system of the Everglades in southern Florida. In GueEason, P. J., ed. Environments of South Florida: Present and Past. Mem. Miami Geo. Survey 2:18-27. Reyes, W. J. 1858. The United States Survey of Township 44S, Range 42E, Florida. Tuomas, T. M. 1974. A detailed analysis of climatological and hydrological records of South Florida with reference to man’s influence upon ecosystem evolution. In GLEason, P. J., ed. Environ- ments of South Florida: Present and Past. Mem. Miami Geol. Survey 2:82-122. U.S.D.A. 1940. Soil Conservation Service, Aerial Photographs. Project ASI 20674. Philadelphia, Pa. . 1946. Florida Everglades Drainage District Soils Maps. Univ. Florida Agr. Exp. Sta., Soil Conservation Service, Washington, D. C. . 1967. Greenacres City, Florida, Topographic quadrangle. Washington, D. C. . 1973. Soil Survey Special Report, Palm Beach County, Florida. Unpublished county document. Florida Sci. 39(4): 230-235. 1976. 236 FLORIDA SCIENTIST [Vol. 39 Biological Sciences COLLECTION OF POSTLARVAL AND JUVENILE HOPLIAS MALABARICUS (CHARACOIDEI: ERYTHRINIDAE) IN FLORIDA’ DaANNIE A. HENSLEY Florida Department of Natural Resources, Marine Research Laboratory, St. Petersburg, Florida 33701 AssTRACT: Twenty-four postlarval and juvenile specimens of Hoplias malabaricus were col- lected in the Little Manatee River drainage, Hillsborough County, Florida. This collection confirms that H. malabaricus has become established in Florida. OccurRENCE of the South American erythrinid Hoplias malabaricus in Florida has been documented by Hensley and Moody (1975). They presented strong evi- dence that the species has reproduced in the drainage of the Little Manatee River. A large number of specimens (126-325 mm SL) was collected in one pond in this drainage system, and histological examination of the gonads has shown that they can become reproductively active in Florida. Because of research pri- orities, only a small section of the Little Manatee River drainage was sampled extensively. H. malabaricus was found in only one pond. Water levels at that time were low and the pond was isolated. In hopes that this was the only locality where H. malabaricus was found, they treated the pond with an ichthyocide. This effort failed to eradicate the species. The present paper verifies the estab- lishment of this species in Florida. During August and September 1975, 24 postlarval and juvenile specimens of H. malabaricus were collected by seine in the same small system of drainage ditches and ponds where Hensley and Moody originally collected them. Due to recent rains, water levels in the area were high, forming a system of intercon- nected swamps and weed-choked ditches and ponds. Aerial surveillance indi- cated that during periods of high water levels, this system has extensive connec- tions with the remainder of the Little Manatee River drainage (Vernon Ogilvie, personal communication). Two water temperature readings of 27 and 29°C were taken on two separate days in the area where the specimens were collected. Seventeen of these specimens are at the Exotic Fish Research Laboratory, Flor- ida Game and Fresh Water Fish Commission, Boca Raton. The smallest speci- mens (18.7-43.3 mm SL) are deposited at the Florida Department of Natural Resources Marine Research Laboratory, St. Petersburg, and were the only ones available to me for examination. An 18.7 mm SL specimen is illustrated in Fig. 1. With the exception of the pectoral fins this specimen resembles the adult. The pectoral fins are the “larval” type with a fleshy base and a fan-shaped membrane bearing only actinotrichia. ‘Contribution Number 268, Florida Department of Natural Resources Marine Research Laboratory. No. 4, 1976] HENSLEY—COLLECTION OF HOPLIAS Za Fig. 1 Postlarval Hoplias malabaricus, 18.7 mm SL. Pectoral lepidotrichia appear to begin to develop between 22 and 30 mm SL (Table 1). With development of the lepidotrichia, the fleshy fin base becomes reduced. Since none of the specimens available to me had developed the adult complement of pectoral lepidotrichia (14-15 total), I have called them postlarvae (Hubbs, 1943). The canine teeth were well developed in all specimens examined. The gut of a 30.6 mm SL specimen was found to contain two fishes which could not be positively identified due to the state of digestion; one cyprinodontiform (16.5 mm SL), probably Gambusia affinis, and one small unidentifiable speci- men. TABLE 1. Number of pectoral lepidotrichia for postlarval Hoplias malabaricus. Number of pectoral SL (mm) lepidotrichia 18.7 : 21.0 u 22.6 0 30.6 3 36.0 12 41.5 13 43.3 13 Due to the great amount of interconnection between localities where this species has been collected and the remainder of the Little Manatee River drain- age during periods of high water levels, H. malabaricus is probably widely dis- tributed within this drainage system. Thus, efforts to eradicate this species seem futile. However, due to its great potential for causing damage to native freshwater fish populations (Hensley and Moody, 1975), its dispersal should be rigorously monitored. It may be possible to contain this species to some extent or to pre- vent its dispersal into particular areas. ACKNOWLEDGMENTS—I thank Charles Futch, Derril Moody, and Mark Berrigan for assistance in the field. I am grateful to Vernon Ogilvie and Paul Shafland of the Florida Game and Fresh Water Fish Commission for their inter- est in this species and for their time spent with me collecting. I am especially thankful to James Seagle for the drawing of the postlarval specimen. Critical re- 238 FLORIDA SCIENTIST [Vol. 39 view of the manuscript was kindly furnished by Charles Futch, Gregory Smith, Dr. Walter R. Courtenay, Jr. and Dr. Frederick A. Kalber. LITERATURE CITED HENSLEY, D. A., and D. P. Moopy. 1975. Occurrence and possible establishment of Hoplias mala- baricus (Characoidei; Erythrinidae) in Florida. Florida Sci. 38:122-128. Husss, C. L. 1943. Terminology of early life history stages of fishes. Copeia 1943:260. Florida Sci. 39(4): 236-238. 1976. Biological Sciences TWINNING IN THE GULF COAST BOX TURTLE, TERRAPENE CAROLINA MAJOR JOHN K. TUCKER AND RICHARD S. FUNK Department of Biological Sciences, Illinois State University, Normal, Illinois 61761 OBSERVATIONS of complete twinning in turtles are rare (for a review, see Yntema, 1970). The only example reported for Terrapene is in T. carolina triun- guis (Agassiz) (Crooks and Smith, 1958). The present paper reports the first set of twins known for T. c. major (Agassiz). An adult female T. c. major collected 30 May 1975 on Fla. Hwy. 22, 2.3 km W of Wewahitchka, Gulf Co., Fla., laid 4 eggs 2 July, 3 of which hatched 12 Sept. 1975. The fourth egg containing dead twins was opened 13 Sept. Measurements of the first three eggs and their single hatchlings will be reported elsewhere. The twins were photographed before preservation and measured with vernier cali- pers shortly after preservation. The egg that contained the twins was somewhat smaller than the other eggs of the clutch at the time of oviposition. The twins’ egg was 32.9 X 21.2 mm while the other three eggs averaged 34.7 X 21.7 mm. Apparently the smaller twin died first; when injected with formalin, it failed to harden properly, while the larger one reacted normally to preservation. It is likely that decomposition products of the smaller twin poisoned the larger one. These twins, like those reported by Yntema (1970) and Crooks and Smith (1958), had a common yolk sac but separate allantoises and amnions. They were oriented plastron to plastron inside the egg, with their posterior ends directed toward the widest end of the egg (Fig. 1). The larger twin is morphologically normal but smaller than any of the normal hatchlings of the same clutch. The three normal sibling hatchlings averaged 32.1 mm in carapace length while the larger twin was 23.6 mm in carapace length. The measurements of the twins are not strictly comparable to those of normal hatchlings because the living hatchlings were measured after normal post-hatching carapace expansion had occurred. But all body parts of the twins are smaller than normal hatchlings. The No. 4, 1976] TUCKER AND FUNK—TWINNING IN BOX TURTLE 239 Fig. 1 (upper left). Twin Terrapene carolina major in situ, with part of egg shell cut away. Fig. 2 (upper right). Twins with entire egg shell cut away, showing intact embryonic membranes of small twin and position of common yolk sac. Fig. 3 (below). Twins removed from egg, showing size dis- parity and posterior curvatures of carapaces. small twin (carapace length 17.2 mm), like the small members of other known sets of turtle twins is deformed, with right pleurals 1-4 divided, central 2 divided, left pleural 4 divided, and left pleurals 1 and 2 fused. ACKNOWLEDGMENTS—We thank L. E. Brown and D. Moll for reviewing the manuscript. LITERATURE CITED Crooks, F. D., anp P. W. Smiru. 1958. An instance of twinning in the box turtle. Herpetologica 14:170-171. YnteMa, C. L. 1970. Twinning in the common snapping turtle, Chelydra serpentina. Anat. Rec. 166:491-498. Florida Sci. 39(4): 238-239. 1976. 240 FLORIDA SCIENTIST [Vol. 39 Biological Sciences ELEMENT CONTENT OF HYDRILLA AND WATER IN FLORIDA’ J. F. Easuey ann R. L. SHIRLEY Department of Animal Science, University of Florida, Gainesville, Florida 32611 AsstractT: Hydrilla verticillata and the water in which it grew were analyzed from a lake and a ditch over 12 mo. Hydrilla from the ditch, compared to that from the lake had more Ca (2.6), Fe (3), Na (1.8), similar amounts of P, Mg, Cr, and less Zn (.8), K (.66), Cu (.07), Mn (.25). Ditch compared to lake water had more Ca (5), Fe (9), Na (3), P (10), Mg (4), Zn (4), Cu (1.6), and similar amounts of Cr, K, Mn. MECHANICAL methods of harvesting aquatic weeds (Grinwald, 1968; Wun- derlich, 1967) are used at times because chemicals may leave undesirable resi- dues and biological controls are not available for most species of weeds. Chemi- cal analysis (Boyd, 1968) and feeding trials with steers (Stephens et al., 1972) de- monstrated that significant amounts of many mineral nutrients are present in aquatic plants. Plants used as feed should have a quantitative elevation of the elements as to season and collection site. Concentrations of 10 nutrient elements in hydrilla (Hydrilla verticillata Royle) and in water at the growing site were compared at approximately monthly intervals throughout a year. Metuops—Hydrilla and water were obtained from Little Lake Fairview, Winter Park and a drainage ditch on the eastern side of Sarasota. Samplings were made at intervals from March 1970 through February 1971. Hydrilla was re- moved from the lake with a mechanical harvester 5-15 m from shore and 1-2 m deep. The ditch was 3 m wide and 1 m deep. Plants from the ditch were gathered with large hand fork and samples of surrounding water were taken in plastic bottles and stored at 4°C. Hydrilla samples were air dried at 60°C and ground in a Wiley mill. Phosphorus was determined by the method of Fish and Subbarow (1925). Atomic absorption spectrophotometry was used to determine Ca, Mg, K, Na, Fe, Cu, Zn, Mn and Cr (Anonymous, 1964). Element content was calculated on the dry wt basis. RESULTS AND Discuss1on—Calcium. Lake hydrilla contained 1.8-5.6% (avg 3.2) Ca and ditch plants had 4.8-14.6% (avg 8.3), P < 0.01 (Table 1). Boyd (1969) reported mean Ca values greater than 4% for hydrilla. Calcium in lake water varied throughout the year from 14-21 mg/1 (avg 16) and in ditch water from 34 to 105 mg/1 (avg 75), P < 0.01, as shown in Table 2. The higher concentration of Ca in ditch water may account for the high Ca content of ditch plants. Cal- cium content varied little from month to month in both lake water and hydrilla. ‘Florida Agricultural Experiment Station Journal Series No. 4841. 241 EASLEY AND SHIRLEY—CONTENT OF HYDRILLA No. 4, 1976] TL61 6/61 ‘stseq yystom AIC, 6I Ee OI el 7 II 9 youd ZI 9 91 II Ee 9% € aye] By/3W ‘ID CSI col OF Cg 99 rP CP youd ELZ SOI FOI 16 ING GEL 998 oyeqy =—-s-3 4/3 ‘uy OFT SOI 961 €SZI_ _—_—‘I6I 9291 youd LLI LEI ESI 601 161 S191 OLFI oye] 3y/SUl ‘UZ, 6 CZ PI rI 91 II ra youd SSE 19 El Sel BGG Cel 9¢ oye] By/Su ‘ND gcse ss TLZST 9S SOIS G9SF_ ss BSL. OLIS youd SI6I FO0IT FOLT I6FI OISE O8IS O6FE oye] 8/3 ‘aq EA g" 0% 0% ET Gil 9'T youd g° g" gs" g’ iP g" 6 aye] % “EN 6'S oP aS I? OF CL 89 y~ud 18 IPD, SL gL £9 o8 ray | aye] % MI g" Gi 9° 9° 9° G; G youd 9° pe gs" 6 2 2 r axe] % ‘SIN ¢ ¢" @ 2 rr 8’ Ns youd ne Si vr e or 2 c oye] % ‘di 001 0'8 06 o9 6'8 SP rs youd VS 9'¢ LY (a 6% GG 61 oye] % “BO 1/01 13/8 PO/L GZ/9 2/9 ~=—-LG/¥ Z1/€ OL6I PPO, Y Ul S9OINOS OM} WOT eT[pAy UI SJUIW][9 [BIOUTUT JUOTIYNU JO UOTZEIYUBOUOT) “[ ATAV 242 FLORIDA SCIENTIST [Vol. 39 The Ca values for hydrilla are greater than those given for 12 land forages in Florida that ranged from 0.2 to 1.6% (Cunha et al., 1964). Phosphorus. Phosphorus concentrations in the water samples from the lake and ditch ranged from 0-0.4mg/1 (avg 0.2) and 0.4-4 mg/1 (avg 1.9), respec- tively, P< 0.01. The mean P concentration of 1729 samples of surface water in the United States was 0.087 mg/1 (0.001-5.0) in Storet (NAS, 1972). Hydrilla from the two sources was quite similar in P content, 0.3 to 0.7% (avg 0.4) and 0.2-0.8% (avg 0.5), respectively. These values are quite close to the 0.4% P for hydrilla reported by Steward (1970). Ditch water contained approximately 9 times more P than lake water, but hydrilla from the ditch had only slightly more P. The overall range in P values from 0.2 to 0.8% in the aquatic plant is double the range of 0.1-0.4% P reported in 12 land forages (Cunha et al., 1964). It is possible to obtain a very wide ratio of Ca to P by including hydrilla at high levels in diets. Stephens et al. (1972) observed that a Ca:P ratio of 17.6:1 in a 33% hy- drilla ration resulted in a retention of only 2.0 g P per day per steer whereas with a Ca:P ratio of 2.7:1 in a 33% hyacinth (Eichhornia crassipes) ration 6.1 g P was retained. Magnesium. Magnesium levels were 3 to 5 mg/1 (avg 3.4) in the lake and 7-16 mg/1 (avg 12.1) in the ditch, P <0.01. Lake values are quite low as concen- trations in 1143 waters had a mean of 14.3 mg/1 (8.5-137) (Storet NAS, 1972). The values for hydrilla from the lake and ditch, 0.3-0.9% (avg 0.6) and 0.4-0.8% (avg 0.6), were not influenced by the approximately 4-fold greater content of Mg in the ditch water. Boyd (1969) reported similar Mg values in three species of water weeds though other macrominerals varied. Values of 12 Florida land forages ranged from 0.02 to 0.5% (Cunha et al., 1964). Potassium. Potassium values for the lake were 2-4 mg/1 (avg 3.0) and 0.8-9 mg/1 (avg 3.3) for the ditch. The mean concentration of 1804 water samples in Storet (NAS, 1972) was 4.3 mg/1 (0.06-370). Hydrilla from the lake, however, had 6.3-10.2% (avg 8.1) K compared to 3.2-7.3% (avg 5.1) from the ditch, P < 0.01. These values are very high as 48 samples of pangola grass analyzed in our labora- tory had 0.11-1.08% (avg 0.54) and 29 samples of Pensacola Bahia grass had 0.72- 2.0% (avg 1.31) K. Sodium. Hydrilla from the lake contained 0.7-0.9% (avg 0.8) Na compared to 0.8-2.0% (avg 1.4) from the ditch, P< 0.01. Lake water varied from 9 to 36 mg/1 (avg 13) and ditch water 15-57 mg/1 (avg 39), P< 0.01. The amount of Na in the plants appears to be related to that in the water as occurred with Ca. Iron. Values for Fe in the hydrilla ranged from 1,104 to 5,180 mg/kg (avg 2,428) for the lake and 2,526-15,271 mg/kg (avg 7,118) for the ditch, P< 0.01. Concentrations of Fe in the water from the lake and ditch were 19-51 wg/1 (avg 34) and 45 to 1718 ug/l (avg 314), respectively. The mean of 1836 samples in Storet (NAS, 1972) was 43.9 pg/1 (0.10 to 4600). The elevated levels of Fe in the water were accompanied by greater concentrations of Fe in the plant. 243 EASLEY AND SHIRLEY—CONTENT OF HYDRILLA No. 4, 1976] 96 Il TL61 8/1 “T/T i Z I é 7 Z € G yud 0 Zz Zz ) € c Pp oye] 1/30 Ig 9 OI c 7 G G L 7 youd P 7 7 9 7 OI G axe] 1/30 ‘uy 6S SF ZE 8% rS 63 IS Se y~:ud FZ 8% oP nye 9I Ze 19 axe] 1/31 ‘uz, SI Ol LI VG GG SI 63 61 youd CI 91 8 II ZI ial OT oye] [/3i ‘no LY ZOE 6ZE IS Z8 Gr LIT LL youd Sh Ir IS GZ £3 Le ef oye] 1/30 ‘ag OF ES LS FS 9G cI 6I PF 6£ youd 9¢ OI 6 II ZI Il OI oyxe'] [/sw ‘en v 6 E € I g" g’ 9 € yud € 6 Z € € € Pp oye] 1/3u ‘yf cl €1 ZI el el D OI 91 g —ud € G G e € € € oye] [/3w ‘BWW 9° ¢ Z Z € (6 I 6) 7 yud Gi 2 I 0 c axe] 1/3w “g 99 £6 GL 6L 101 6S €9 SOI LG youd 0Z 61 1Z ial ial jj ial oye] [/Su ‘eg Z/Z1_ ~—«6G/ OI 1/01 LZ/8 PZ/L GZ/9 2/9 66/F Z1/€ OL6I ‘RPHO[Y Ul S9dINOS OM] WOOL, 19JVM UT SJUIWI]O [BIOUTUU JUSTAQNU JO UONBIQUIOUOT) °F ATAV TL 244 FLORIDA SCIENTIST [Vol. 39 Copper. Copper concentrations in the water were generally higher in the ditch, 10-29 pg/1 (avg 19) than in the lake which ranged 8-16 pg/1 (avg 12), P< 0.01. The mean Storet (NAS, 1972) concentration in 1871 samples was 13.8 pg/1 (0.8-280.0). Hydrilla samples from the lake, however, were much higher in Cu, 36-328 mg/kg, (avg 145) than those from the ditch, range 0-25 mg/kg (avg 10), P <0.01. Values for the hydrilla from the ditch are typical of land for- ages. The high concentrations of Cu in the hydrilla from the lake may have been due to treatment of the water for algae. The applied Cu may have remained at a high concentration only a short time due to rapid assimilation in the plant tissue, precipitation in sediment, or by dilution with fresh water. Sutton and Blackburn (1971) reported increased amounts of copper occurred in hyacinths when Cu in the water was increased from 0.5 to 4.0 mg/1. Buchman, Shirley and Killinger (1968) found that top-dressing star millet (Pennisetum americanum (L.) K. Schum.) with 28 kg copper sulfate per hectare 7 days prior to harvest in- creased Cu content from 8 to 88 mg/kg though the millet was irrigated with overhead sprinkling. Zinc. Ranges in zinc values for the hydrilla were similar; from the lake 109- 1612 mg/kg (avg 535) compared to 108-1626 mg/kg (avg 397) from the ditch. Land forages usually contain 15-30 mg of Zn/kg. Zinc concentrations in water from the lake and ditch were 13-61 yg/1 (avg 28) and 28-676 p/1 (avg 113), re- spectively. The mean Storet (NAS, 1972) value of 1883 samples was 51.8 wg/1 (1.0 to 1,182). Manganese. Lake hydrilla ranged from 97-866 mg Mn/kg (avg 360) with January, February, March and April values 2-4 fold higher than other months. Hydrilla from the ditch was in the range of land forage, 35-165 mg/kg (avg 92). Concentration in lake water was 4-10 (avg 5.3) and in the ditch, 4-10 ug/1 (avg 6.2). The mean Storet (NAS, 1972) Mn in 1818 samples was 29.4 wg/1 (0.2-3,230). Chromium. The Cr in hydrilla from the lake and ditch was 3-32 (avg 12) and 4-32 mg/kg (avg 13), respectively. Concentrations of Cr in the water from the lake and ditch were 0-5 (avg 2.3) and 1-5 ywg/1 (avg 2.6). Chromium has been demonstrated to be required in carbohydrate metabolism (Schwarz and Mertz, 1959). ACKNOWLEDGMENT—Support from the Florida State Department of Natural Resources is gratefully acknowledged. LITERATURE CITED Anonymous, 1964. Analytical Methods for Atomic Absorption Spectrophotometry. Perkin-Elmer Corp. Norwalk, Connecticut. Boyp, C. E. 1968. Evaluation of some common aquatic weeds as possible feedstuffs. Hyacinth contr. J. 7:26-27. . 1969. The nutritive value of three species of water weeds. Economic Bot. 23:123-127. Bucuman, D. T., R. L. SHIRLEY AND G. B. KILLINGER. 1968. Nitrate, ammonia and methemoglobin in sheep when fed millet containing different levels of copper. Proc. Soil Crop Sci. Soc. Florida 28:209-215. Cunna, T. J., R. L. Saintey, H. L. CHApMan, Jr., C. B. AMMERMAN, G. K. Davis, W. G. Kirk AND J. F. HentcEs, Jr. 1964. Minerals for Beef Cattle in Florida. Agric. Exper. Sta. Univ. Florida Bull. 683. Gainesville. No. 4, 1976] EASLEY AND SHIRLEY—CONTENT OF HYDRILLA 245 Fiske, C. A., AND I. SuBBAROW. 1925. The colorimetric determination of phosphorus. J. Biol. Chem. 66:375-400. GrINWALD, M. E. 1968. Harvesting aquatic vegetation. Hyacinth Contr. J. 7:31-32. NATIONAL ACADEMY OF SCIENCES. National Academy of Engineering. 1972. Water Quality Criteria. Supt. of Doc. Washington, D. C. ScHwarz, R., AND W. MErTz. 1959. Chromium (111) and the glucose-tolerance factor. Arch.Bio- chem. Biophys. 85:292-295. STEPHENS, E. L., J. F. Eastey, R. L. SHirvey Anp J. F. HENTGCEs, JR. 1972. Availability of nutrient mineral elements and potential toxicants in aquatic plant diets fed steers. Soil Pl. Sci. Soc. Florida Proc. 32:30-32. STEWARD, K. K. 1970. Nutrient removal potentials of various aquatic plants. Hyacinth Contr. J. 8: 34-35. Sutton, D. L., anp R. D. BLAckBuRN. 1971. Uptake of copper by water hyacinth. Hyacinth Contr. J. 9:18-20. WunbeErLIcH, W. E. 1967. The use of machinery in the control of aquatic vegetation. Hyacinth Contr. J. 6:22-24. Florida Sci. 39(4): 240-245. 1976. EFFECTS OF A HURRICANE ON THE FISH FAUNA AT DESTIN, FLORIDA—Stephen A. Bortone, F aculty of Biology, University of West Florida, Pensacola, Florida 32504 ABSTRACT: A pre- and post-storm SCUBA inspection of relative abundance of fish species was conducted at a rock jetty in the northern Gulf of Mexico. As little or no change occurred in the fish fauna between the sampling dates, it is concluded that the storm had little effect on the fauna. EFFECTS of severe storms and hurricanes on fish communities are docu- mented (e.g., Breder, 1962; Tabb and Jones, 1962; Hubbs, 1962). Additionally, several studies have assessed the effects of storms and hurricanes on fishes occur- ring at reef and reef-like areas in tropical-subtropical regions. However, reports of those effects have not shown consistent results. Robins (1957) indicated that several reef-associated fish species were found dead or injured because their gill areas were damaged by the heavy sand load and seas during a tropical storm near Key Biscayne, Florida. Beecher (1973) noticed a slight decrease in avg length of a population of Pomacentrus variabilis after the occurrence of hurricane winds and seas near a rock jetty at St. Andrews Bay, Florida. Springer and McErlean (1962) noted a lack of displacement of reef fish populations by a severe storm which otherwise destroyed much of the coral formation in the area. On the morning of 23 September 1975 Hurricane Eloise reached the coastal northern Gulf of Mexico between Destin and Panama City, Florida. The occur- rence of this storm presented a unique opportunity to evaluate the potential effects such a severe storm may have on a shallow rock-jetty community com- posed of many reef fishes. No weather recording station is located at Destin, but the storm severity was recorded a few km east of Destin at Fort Walton Beach. The highest winds were recorded at 145-195 kph and the severest winds were from the north. The tide surge was 1.5 m above normal and seas were approximately 4 m high. The east and west jetties at East Pass, Destin, Florida were finished in 1968 and numerous reef fishes have since taken up permanent or transitory residence 246 FLORIDA SCIENTIST [Vol. 39 at the jetties (Hastings, 1972). Hastings noted a preponderance of reef fishes during his long term study of seasonal and successional fish populations on these jetties. Pre-storm inspection of the ocean side of the west jetty was conducted on 20 September 1975 and a post-storm investigation was done on 28 September 1975. Pre-storm site data were: tide, flooding and flood; bottom and surface water temp, 28°C; bottom and surface salinity, 32 °/,,; time, 11:00-14:30 CDT; depth, 2-6 m; visibility, 3-5 m. Post-storm site data were: tide, ebbing; bottom water temp, 27°C; surface water temp, 23°C; bottom salinity, 32°/,.; surface salinity, 18 °/,,; time, 11:30-14:30 CDT; depth, 2-6 m; visibility, 1-2 m. SCUBA was uti- lized to conduct the underwater assessment of species present and their approxi- mate abundance according to the following scale: A=abundant, more than 25 individuals of a species per inspection dive; C=common, 11-25; F = frequent, 6-10; 0 = occasional, 2-5; R=rare, 1. Species occurrence and abundance data for both pre- and post-storm inspec- tion dates are presented in Table 1. Twenty-seven fish species (90% of the total fauna seen on both dates) were observed on the pre-storm inspection and only 20 (66.7% of the total fauna) were seen after the storm. However, a faunal com- parison through SCUBA observation is affected by water clarity and other fac- tors, thus it is reasonable to exclude from this analysis species which were _re- corded but once on either sample date. Even under ideal conditions experience indicates that a single representative of a species may be missed. If we exclude species which were seen once as single individuals, 91.7% of the total fauna (22 species) was present before the storm and 79.2% (19 species) after the storm. A Sign test (Seigel, 1956) indicated there is a significant difference (at the 0.05 level) between the pre- and post-storm fish faunas including all species. However, if species recorded only once are again excluded from the comparison, there is no statistically significant difference in the fish fauna between sampling dates. Little observable change was strongly evident in species populations which were abundant or common. However, I did note decreases in Orthopristis chry- soptera and Chaetodipterus faber and an increase in Lutjanus griseus after the storm. The most obvious change in the rock-jetty community was reduction in length of attached algae (principally Polysiphonia and Gracilaria) from approxi- mately 50-75 mm to only 10-20 mm. Also, more sand was seen on the rocks com- prising the jetty. No apparent behavioral differences were noted in the species common to both sample dates. Also, I saw no injuries or unusual wounds which may have been caused by large waves or tidal surge. Discussion—Few major changes in the fish community occurred as a result of a severe hurricane in the immediate vicinity of the Destin jetty in the Fall 1975. Some authors have noted dramatic changes in fish faunas due to storms, but the apparent lack of effect at Destin may be explained in several ways. Changes in fish populations in estuarine areas have been attributed to oxygen depletion brought on by the vertical mixing caused by turbulent seas (Creaser, 1942). Although dissolved oxygen was not measured during this study, the ocean No. 4, 1976] BORTONE—EFFECTS OF HURRICANE 247 TaBLE 1. Relative abundance of species observed prior to (20 September 1975) and after (28 September 1975) Hurricane Eloise at the West Jetty, Destin, Florida. (A = abundant, 25; C=com- mon, 11-25; F= frequent, 6-10; O= occasional, 2-5; R= rare, 1; +, -, and ¢ refer to an increase, de- crease, or no change in the number of individuals seen after the storm). Sampling Date Net Species 20 Sept. ’75 28 Sept. ’75 Change Narcine brasiliensis (Olfers) Dasyatis sp. Gobiesox strumousus Cope Serraniculus pumilio Ginsburg Serranus subligarius (Cope) Caranx bartholomaei (Cuvier) C. hippos (Linnaeus) Lutjanus griseus (Linnaeus) L. synagris (Linnaeus) Orthopristis chrysoptera (Linnaeus) Diplodus holbrooki (Bean) Lagodon rhomboides (Linnaeus) Chaetodipterus faber (Broussonet) Chaetodon ocellatus Bloch Holacanthus bermudensis Goode Abudefduf saxatilus (Linnaeus) Pomacentrus variabilis (Castelnau) Halichoeres bivittatus (Bloch) Thallassoma bifasciatum (Bloch) Nicholsina usta (Valenciennes) Sparisoma radians (Valenciennes) Astroscopus y-graecum (Cuvier) Hypleurochilus geminatus (Wood) Acanthurus chirurgus (Bloch) A. randalli Briggs and Caldwell Paralichthys albigutta Jordan and Gilbert Balistes capriscus Gemlin Cantherhines pullus (Ranzani) Sphoeroides nephelus (Goode and Bean) Chilomycterus schoepfi (Walbaum) mann ZArnmonmnonnr' © ! eval tr (@) 3 Cr@xe) Cre) 2 = ap (@). ' ' QQ! OOF Prod' CONF AROMAS D' SO Oe * i] ' OnDm ' side of the jetty is constantly flushed by oxygenated ocean water. Therefore, oxygen depletion is not likely to occur at the Destin jetty. Robins (1957) attributed deaths and injury to the strong surge and sediment load caused by storm winds. Even though seas and tidal surge were higher than normal at Destin, one must consider that the strongest storm winds were from the north. The ocean side of the jetty, therefore, was not subject to a long fetch and correspondingly, the severest storm seas. Springer and McErlean (1962) and Bortone (1971) noted that reef species may protect themselves from a strong surge or current by taking up positions under or behind reef structures. Numer- ous such protected areas exist at the Destin jetty which is composed of large, irregular rocks. Changes observed in several species may be explained by factors other than the storm. Orthopristis chrysoptera forms loosely aggregated schools and may 248 ? FLORIDA SCIENTIST [Vol 39 have migrated as a group to the bay side of the jetty. This species is often con- sidered an estuarine-bay species. Chaetodipterus faber has pelagic habits and schools are observed irregularly at reef sites and as they constantly move a diver may miss seeing them. Lutjanus griseus was more numerous after the storm, but they normally increase during the fall at the Destin jetties (Hastings, 1972). The storm may have long term effects on the area. Many species at Destin are presumed to migrate to deeper, offshore reefs at the onset of colder weather (Hastings, 1972). The hurricane may have lowered the water temperature in the coastal northern Gulf which could initiate a precocious offshore movement. Also the obvious depletion of algae may subsequently limit the number of grazers (Scaridae and Acanthuridae) which occur in the area. The apparent “survival” of the reef-fish fauna at Destin may be attributed to several of the previously mentioned factors or that the fauna is comprised of colonizing species, and these may be hardier and less susceptible to fluctuations in parameters than are other reef species which are indigenous to lower latitude coral reefs. ACKNOWLEDGMENTS—I thank Philip A. Hastings, Robert W. Chapman, and Michael Applegate for diving assistance; Dr. J. L. Oglesby for advice on statis- tical treatment; and Dan Rice and Phyllis Polland of the U.S. National Weather Service, Pensacola for data concerning Hurricane Eloise. Dr. Robert W. Hast- ings kindly commented on the manuscript and offered several suggestions. LITERATURE CITED BeEecueER, H. A. 1973. Effects of a hurricane on a shallow-water population of damsel fish, Poma- centrus variabilis. Copeia 1973:613-615. BorTong, S. A. 1971. Studies on the biology of sand perch, Diplectrum formosum (Perciformes: Serranidae). Florida Dept. Nat. Res. Tech. Ser. 65:1-27. BREDER, C. M. 1962. Effects of a hurricane on the small fishes of a shallow bay. Copeia 1962:459-462. Creaser, E. P. 1942. Fish mortality resulting from effects of a tropical hurricane. Copeia 1942:48-49. Hastincs, R. W. 1972. The Origin and Seasonality of the Fish Fauna on a New Jetty in the North- eastern Gulf of Mexico. Ph.D. dissert. Florida State Univ. Tallahassee. Husss, C. 1962. Effects of a hurricane on the fish fauna of a coastal pool and drainage ditch. Texas J. Sci 14:289-296. Rosins, C. R. 1957. Effects of storms on the shallow-water fish fauna of Southern Florida with new records of fishes from Florida. Bull. Mar. Sci. Gulf Carib. 7:266-275. SIEGEL, S. 1956. Nonparametric Statistics for the Behavioral Sciences. McGraw-Hill. New York. SPRINGER, V. G., AND A. J. MCERLEAN. 1962. A study of the behavior of some tagged South Florida coral reef fishes. Amer. Mid]. Nat. 67:386-397. Tass, D. C., anp A. C. Jones. 1962. Effect of Hurricane Donna on the aquatic fauna of north Flor- ida Bay. Trans. Amer. Fish. Soc. 91:375-378. Florida Sci. 39(4): 245-248. 1976. No. 4, 1976] DAVIES AND BORTONE—FOODS OF BILLFISHES 249 Biological Sciences PARTIAL FOOD LIST OF THREE SPECIES OF ISTIOPHORIDAE (PISCES) FROM THE NORTHEASTERN GULF OF MEXICO Jay H. Davies! AND STEPHEN A. BORTONE Faculty of Biology, University of West Florida, Pensacola, Florida 32504 AxssTRACT: Stomach analyses were performed on 53 white marlin, Tetrapturus albidus; 11 sail- fish, Istiophorus platypterus; and 5 blue marlin, Makaira nigricans captured in the Gulf of Mexico, 30-100 km S of Pensacola, Florida from May to October, 1974. Stomach content analyses were con- ducted using frequency of occurrence, numerical, and gravimetric (wet wt) methods. Stomachs of white marlin and sailfish most frequently contained Euthynnus sp., Auxis sp., squid, and Atlantic moonfish, Vomer setapinnis. White marlin were also reported for the first time feeding on barracuda and puffers. Thunnus sp., Euthynnus sp., and Auxis sp. were most common food items of blue marlin, however, cephalopods may be of some importance in their diet. BILLFISHES are economically important to the marine sport fishing industry of many coastal areas in the United States. Commercial longline fishing may be endangering this industry by over-fishing billfish populations in certain areas. Talbot and Wares (1975) reported that after entry of commercial longline fishing in the Pacific Ocean off Mexico, there was a decrease in the catch-per-unit-effort of striped marlin, Tetrapturus audax (Philippi); blue marlin Makaira nigricans Lacépéde; and black marlin, Makaira indica (Cuvier) and a decrease in the avg wt of striped marlin. In order to effectively manage existing billfish stocks, an understanding of their biology is essential. An analysis of the food of these fishes will help define the trophic relationships of billfishes and their pelagic environ- ment. While associated with the National Marine Fisheries Service at Panama City, Florida, the senior author had an opportunity to collect stomach contents of bill- fishes captured with hook-and-line by sport fishermen. These data are the first indication of the food of billfishes in the northeastern Gulf of Mexico. MATERIALS AND METHODs—The stomach contents of 53 white marlin, Tetrap- turus albidus Poey; 11 sailfish, Istiophorus platypterus (Shaw and Nodder); 5 blue marlin, Makaira nigricans Lacépéde captured in the Gulf of Mexico, 30-100 km S of Pensacola, Florida from May to October, 1974 were examined. Upon landing, stomachs (including the esophagus, but excluding the intestine) were removed and the contents preserved in 10% formalin. Some loss of food by re- gurgitation may have occurred prior to removal of stomachs. Body length of bill- fish was measured from the anterior tip of the lower jaw to the posterior margin of the middle caudal rays according to Rivas (1956). Food items were identified to species whenever possible. Hard parts such as skulls, gillrakers, vertebrae, 'Present address: 1206 Park Street, Elizabeth City, North Carolina 27909 250 FLORIDA SCIENTIST [Vol. 39 spines and rays proved valuable in the identification of fish items. Data presented by Mansueti and Mansueti (1962), de Sylva (1955) and Starks (1950) were used to identify scombrids. Carangids were identified according to Ginsburg (1952). TABLE 1. List of food items found in 53 white marlin stomachs (145-185 cm Body Length) col- lected in the northeastern Gulf of Mexico. Frequency of Percent Food Percent Wet Percent Occur- Occur- Item Number Number Wt (g) Wt rence rence SCOMBRIDAE: Euthynnus alletteratus 44 4.7 1235.8 19.5 16 30.1 Euthynnus sp. 73 7.8 1096.7 17.3 22 41.5 Auxis sp. 51 5.5 1322.4 20.9 20 Sail Thunnus sp. 1 0.1 19.0 0.3 1 1.8 Unidentified scombrids 10 1.0 70.2 1.1 8 15.0 TOTAL Scomsrips’ 179 19.3 3744.1 59.3 34 64.1 CARANGIDAE: Caranx crysos 3 0.3 902.4 14.2 3 5.6 Caranx sp. P 02 13.9 0.2 1 1.8 Chloroscombrus chrysurus 3 0.3 2.6 0.0 3 5.6 Vomer setapinnis 683 73.6 1136.8 18.0 15 28.3 Unidentified carangids 8 0.8 27.0 0.4 at 13.2 TOTAL CARANGIDS 699 75.4 2082.7 33.0 23 43.3 EXOCOETIDAE: Hemiramphus brasiliensis 2 0.2 196.0 Bal 2 Ont Hemiramphus sp. 3 0.3 154.9 2.4 2 Sn TOTAL EXOCOETIDS 5 0.5 350.9 5.9 4 7.5 SPHYRAENIDAE: Sphyraena sp. 1 0.1 se 0.0 1 1.8 TETRAODONTIDAE: . Unidentified tetraodontids 7 0.7 9.9 0.1 4 TE BALISTIDAE: Balistes sp. 2 0.2 3.2 0.0 2 3.7 Unidentified fish 9 0.9 19.7 0.3 i 13.2 CEPHALOPODA: Unidentified squid 25 2.6 99:6 1.5 17 32.0 Empty ae B8 on is 16 30.1 No. 4, 1976] DAVIES AND BORTONE—FOODS OF BILLFISHES 251 Coryphaenids were identified according to Collette et al. (1969). Stomach anal- yses were conducted according to methods described by Windell (1971): fre- quency of occurrence, number of stomachs in which each food item occurred; numerical, number of individuals of each food item; and gravimetric, wet wt of each food item, measured to nearest 0.1 g. OBSERVATIONS AND Discussion—The exocoetids (Tables 1 and 3) probably represent bait since ballyhoo, Hemiramphus brasiliensis, are a popular bait of local anglers and because all exocoetids found in billfish stomachs were relatively undigested compared to other food items examined. Stomachs of white marlin most frequently contained squid, Auxis sp., Eu- thynnus sp., and Atlantic moonfish, Vomer setapinnis (Table 1). The blue runner, Caranx crysos, accounted for 14.2% of the food by wt, but was not important in number or frequency of occurrence. Food item wt may be exaggerating the importance of this species in white marlin diet as one blue runner weighed 977 g and accounted for 97.1% of the food item wt. Importance of blue runner as a food item is probably more accurately reflected in the number of individuals (3) found and its low frequency of occurrence (5.6%). Wallace and Wallace (1942) and de Sylva and Davis (1963) reported round herring, Etrumeus teres, as occurring most frequently in stomachs of white marlin caught off the coast of Maryland, while scombrids and carangids occurred at a lower frequency of occurrence than re- ported in the present study. Differences in diet between areas may reflect dif- TABLE 2. List of food items found in 5 blue marlin stomachs (180-254 cm body length) collected in the northeastern Gulf of Mexico Frequency Percent Percent Wet Percent of Occur- Food Item Number Number Wt (g) Wt Occurrence rence SCOMBRIDAE: Euthynnus sp. 4 30.7 77.5 3.0 2 40.0 Auxis sp. 2 15.3 28.6 eT 1 20.0 Thunnus thynnus 1 7.6 30.7 1.2 1 20.0 Thunnus sp. 2 15.3 38.8 1.5 2 40.0 TOTAL SCOMBRIDS 9 69.2 175.6 6.9 3 60.0 CARANGIDAE: Caranx crysos 1 7.6 713.9 28.3 1 20.0 Chloroscombrus chrysurus 1 7.6 0.5 0.0 it 20.0 TOTAL CARANGIDS 2 15.3 714.4 28.4 1 20.0 CoryYPHAENIDAE: Coryphaena hippurus 1 7.6 1622.3 64.5 ] 20.0 Unidentified fish 1 7.6 2.8 0.1 ] 20.0 Empty ---- ---- ---- ---- 1 20.0 252 FLORIDA SCIENTIST [Vol. 39 ferences in distribution of prey species and their abundance between localities. Squid was one of the three most frequently occurring food items of white mar- lin in this study and studies by Wallace and Wallace (1942), de Sylva and Davis (1963), and Krumholz and de Sylva (1958). The present study reports for the first time white marlin feeding on barracuda and puffers. Euthynnus sp., Auxis sp., Atlantic moonfish, and squid were the most com- mon items in stomachs of sailfish (Table 3). Only one pompano dolphin, Cory- phaena equisetis, was found, and it accounted for 17.0% of the food wt. Voss (1953) examined 241 sailfish and reported little tuna, Euthynnus alletteratus; and flying squid, Stenoteuthis bartrami, as numerically important foods. Scombrids (i.e., Euthynnus sp., Auxis sp., and Thunnus sp.) comprised the largest portion of blue marlin stomach contents by frequency of occurrence and number of individuals, while blue runner and dolphin, Coryphaena hippurus, were dominant food items by wt (Table 2). The disparity between analytical methods occurs because only one blue runner and one dolphin were found, but they were large fish and accounted for 28.3% and 64.5%, respectively, of food wt. TABLE 3. List of food items found in 11 sailfish stomachs (149-167 cm body length) collected in the northeastern Gulf of Mexico. Frequency Percent Percent Wet Percent of Occur- Food Item Number Number Wt(g) Wt Occurrence rence SCOMBRIDAE: Euthynnus alletteratus 8 212 344.6 18.8 4 36.3 Euthynnus sp. 12 3.4 228.1 12.4 4 36.3 Auxis sp. : 5 1.4 174.6 9.5 3 27.2 TOTAL SCOMBRIDS 25 Ta WAG 40.9 8 one CARANGIDAE: Caranx crysos 1 0.2 14.3 0.7 1 9.0 Vomer setapinnis 310 88.3 632.8 34.6 6 54.5 Unidentified carangid 1 0.2 21.4 || 1 9.0 TOTAL CARANGIDS 312 88.8 668.5 36.6 6 54.5 EXOCOETIDAE: Unidentified exocoetidae 2, 0.5 37.8 2.0 ] 9.0 CORYPHAENIDAE: Coryphaena equisetis i 0.2 311.4 17.0 J) 9.0 Unidentified fish 5 1.4 34.8 1.9 3 27.2 CEPHALOPODA: Unidentified squid 6 1.7 25.2 1.3 5 45.4 Empty Bes we ees at 3 27.2 No. 4, 1976] DAVIES AND BORTONE—FOODS OF BILLFISHES 253 Frigate mackerel, Auxis thazard; blackfin tuna, Thunnus atlanticus; skipjack tuna, Euthynnus pelamis; dolphin, and cephalopods occurred in stomachs of blue marlin caught off the Bahamas (Krumholz and de Sylva, 1958). De Sylva (1974) reported tunas, frigate mackerel, and cephalopods as comprising the main food items of blue marlin in the Atlantic Ocean. Euthynnus sp., Auxis sp., Atlantic moonfish and squid apparently comprise the main food of white marlin in the northeastern Gulf of Mexico. Conclusions concerning the main diets of sailfish and blue marlin could not be made because of limited sample size (N=16). However, stomach contents of sailfish were similar to white marlin. The five blue marlin had consumed mostly scombrids, (Thunnus sp., Euthynnus sp., and Auxis sp.,) but cephalopods may also be impor- tant in their diet. Additional studies are still needed to make comparisons of bill- fish food from the Gulf of Mexico with other areas. ACKNOWLEDGMENTS—We thank the members of the Pensacola Big Game Fishing Club and other billfishermen of the Pensacola area, whose cooperation and interest made this study possible. We also thank Luis R. Rivas and the Na- tional Marine Fisheries Service, Panama City for their assistance. J. W. Jolley, Jr. gave valuable critical advice concerning the manuscript. LITERATURE CITED CoLLeETTE, B. B., R. H. Gisss, anp G. E. Ciiprper. 1969. Vertebral numbers and identification of the two species of dolphin (Coryphaena). Copeia 1969:630-631. Ginspure, I. 1952. Fishes of the family Carangidae of the northern Gulf of Mexico and three related species. Publ. Inst. Mar. Sci. Texas 2:43-118. KruMHO1z, L. A., AND D. P. DE SyLva. 1958. Some foods of marlins near Bimini, Bahamas. Bull. Amer. Mus. Nat. Hist. 114:377-416. MansvuETI, R. J., AND A. J. MANSUETI. 1962. Little tuna, Euthynnus alletteratus, in northern Chesa- peake Bay, Maryland, with an illustration of its skelton. Chesapeake Sci. 3:257-263. Rivas, L. R. 1956. Definitions and methods of measuring and counting in billfishes (Istiophoridae, Xiphiidae). Bull. Mar. Sci. Gulf Carib. 6:18-27. Starks, E. C. 1950. The osteology and mutual relationships of the fishes belonging to the family Scombridae. California Fish Game, Fish Bull. 79:77-99. Sytva, D. P. pe 1955. The osteology and phylogenetic relationships of the blackfin tuna, Thunnus atlanticus (Lesson). Bull. Mar., Sci. Gulf Carib. 5:1-41. . 1974. Life history of the Atlantic blue marlin, Makaira nigricans, with special reference to Jamaican waters (abstract). p. 80. In R. S. Soomura AND F, WILLIAMs (ed.). Proc. Internat. Billfish Symp. Kailua-kona, Hawaii, 9-12 August 1972. Part 2. Review and contributed papers. NOAA Techn. Rept. NMFS SSRF-675. , AND W. P. Davis. 1963. White Marlin, Tetrapturus albidus, in the Middle Atlantic Bight, with observations on the hydrography of the fishing grounds. Copeia 1963:81-99. TALsoT, G. B., anpD P. G. Wares. 1975. Fishery for Pacific billfish off Southern California and Mex- ico, 1903-69. Trans. Amer. Fish. Soc. 104:1-12. Voss, G. L. 1953. A contribution to the lift history and biology of the sailfish, Istiophorus ameri- canus Cuv. and Val., in Florida waters. Bull. Mar. Sci. Gulf Carib. 3:206-240. Wa . ace, D. H., anp E. M. WALLACE. 1942. Observations on the feeding habits of the white marlin Tetrapturus albidus Poey. Publ. Chesapeake Bio. Lab. Maryland Dept. Res. Educ. 50:1-10. WINDELL, J. T. 1971. Food analysis and rate of digestion. Pp. 215-226. In W. E. Ricker (ed.) Methods for Assessment of Fish Production in Fresh Water (2nd ed.). Blackwell Scientific Publ. Oxford. Florida Sci. 39(4): 249-253. 1976. 254 FLORIDA SCIENTIST [Vol. 39 Biological Sciences THE INFLUENCES OF INTRAVENOUSLY ADMINISTERED DIMETHYL SULFOXIDE ON REGIONAL BLOOD FLOW Davip W. WASHINGTON! AND WILLIAM P. FIFE Department of Biology, Texas A&M University, College Station, Texas 77843 Asstract: The effects of dimethyl sulfoxide (DMSO) on regional blood flow were determined in rats using Sapirstein’s method for the fractional distribution of **Rb. In the control, 60 white rats were anesthetized with sodium pentobarbital and then given approximately 4.5 million dpm of **Rb by the femoral vein. The experimental group was given 0.5 gskg of pure DMSO via the contra- lateral vein 5 min prior to “Rb injection. Animals in both groups sacrificed at 2, 5, 10, 30, 60, and 300 sec showed no significant changes in the blood flow to the heart, lungs, kidneys, thyroids, brain or skin; however, changes were observed in the livers, stomachs, spleens, guts, and carcasses of the experimental group. DIMETHYL SULFOXIDE (DMSO) has been used in the treatment of arthritis and has been reported to possess unique medicinal properties (Jacab and Wood, 1971). Clinical studies with DMSO began in the United States in 1963. However, its use was temporarily halted by the FDA when it was suspected that DMSO was capable of producing opacities in lenses. A partial resumption of clinical testing was permitted in 1966. Despite the wealth of information concerning the effects of DMSO, its exact mechanism of action remains a subject for debate. Many investigators have described its ability to enhance the absorption of other drugs by serving as a penetrant carrier (Jacab et al., 1969). Kligman (1965) and Adamson et al. (1966) suggested that the primary action of DMSO is to provoke a histamine-like response and therefore cause vasodilation of the peripheral arterioles. In the present study we wanted to determine whether DMSO (1) produces the same effect on the capillary beds of all organs, (2) alters blood flow or capil- lary permeability and, (3) has any effect on the permeability of the blood-brain barrier. We used Sapirstein’s technique (1956, 1958) for the determination of regional blood flow by the fractional distribution of an indicator. Accordingly, intravenous injections of **Rb were followed by rapid sacrifice of the animals at a predetermined exposure time and the removal of the organs for the determi- nation of their isotope content. This method has been widely used for the mea- surement of regional blood flow in small laboratory animals under a number of experimental conditions. MATERIALS AND METHODS—Sixty young rats of uniform stock ranging from 133-346 g wt were divided into a DMSO-treated series and a control series. All animals were in the post-absorptive state, having been fasted 12-16 hr. They were anesthetized with sodium pentobarbital injected intraperitoneally at a dose of 40 mg/kg body weight. The control series consisted of 30 animals subdivided into 6 groups of 5 rats each. These rats were used to establish the normal accumulation pattern of “Rb 'Present address: Department of Biological Sciences, Florida Technological University, Orlando, Florida 32816 No. 4, 1976] WASHINGTON AND FIFE—DIMETHYL SULFOXIDE 255 into the extravascular spaces or compartments described by Black et al. (1956). Following anesthesia, each animal received approximately 4.5 million dpm pf “Rb administered directly into the femoral vein. The animals were subdivided according to the following schedule and sacrificed with a mallet driven hatchet. In this technique the blood flow is abruptly interrupted by cutting through the thorax just below the axillae. The heart is unharmed by this action; however, the large vessels are severed and the circulation immediately interrupted. Time of Sacrifice After Number Subgroup Injection in Seconds of Rats 1 2 ) 2 5 5 3 10 5 4 30 5 5 60 5 6 300 5 The various organs were immediately removed, weighed and placed in plas- tic counting vials for assay in a gamma well. A vial containing *’Rb of equiva- lent activity and volume as the injected dose was prepared for each subgroup. It was absorbed in sponge strips of sizes approximating the mean volumes of the organ samples to be examined. These vials were counted and served as standards for each group. The DMSO treated series consisted of 30 rats subdivided in the same manner as the controls. Both femoral veins were exposed and 0.5 g/kg of pure analytical grade dimethyl sulfoxide was administered into one vein 5 min prior to the injec- tion of *Rb into the contralateral vein. Blood samples were not taken for assay and consequently a significant percentage of the injected **Rb was lost due to blood loss associated with the sacrifice procedure. The counts for each organ were, therefore, converted to percentage of recovered dose rather than the per- centage of the injected dose to maintain the quantitative relationship in flow distributions. The regional blood flow per g of organ wt was then calculated from these data in concert with the cardiac output taken to be 205 ml/kg/min as re- ported by Sapirstein (1956). ResuLts—Table 1 summarizes the fractional distribution of **Rb (regional blood flow) per g of organ wt. Intravenous injections of DMSO produced no significant changes in the blood flow to the heart, lungs, kidneys, thyroids, brain or skin. Although these organs exhibited several variations in flow patterns, none of the fluctuations between control and DMSO treated groups for the same time period were statistically significant. We noted that DMSO, under these experi- mental conditions, produced no significant changes in the permeability of the blood-brain barrier. Table 1 shows that DMSO influenced blood flow changes in the liver, stom- ach, spleen, gut and carcass (musculature minus the skin and viscera). The liver, gut and carcass each demonstrated a significant blood flow change during only one observational interval. The stomach, on the other hand, demonstrated changes at 2, 5 and 300 sec after the injection of **Rb, while the flow in the spleen was changed at 5 and 300 sec. FLORIDA SCIENTIST [Vol. 39 256 a 3 ee eee es EE ae ia Iv Iv vO" FO’ LOG LOE ro) 6LV 19 e¢ ol 61 269° 6 89° OL ESI OT CLG 9S E ydxq = “1yu0D OO€ LY OT It ‘ydxq oT cl cl Li 9T cl oT ae (ae Iv Iv (ae ae (ae £0" vO’ v0 vO" cO" ST 0c PST O$'T 6E'T scl LTT 89'€ PLS 69'¢ cO'r OGY Sle cVe SLE cee Iv ol a c¢ OV cc ¢¢ cy 8s" Lg €s 18’ cg oL9 EST I¢ Lei cg LG OS oVV i SV olV 8¢ Lo OV €S SEs 66° col OTT Sel EST 9¢'T col CoG 68G OLS IVG I6'T (YES GOG ‘quo’ "ydxq ‘quoy ydxq “quop ydxq “QUOD 09 Ol ‘(eg =e) adueyo jue [equouttiedxe pur (43U07)) [o1QUOD BUIPN[OU! QyYy, spuooes “OUT, oylusis e peonpoid yuowyee1 OSG IU} seyeorpul jo UONNLSIp [euoTORIy oy} Aq poutuiiayep se uri /3 ul passoidxa MOTJ poo[q OT 9T sseoled Unis uleig splorA sAouply my uaa{ds yoruloys IOAVT ssun’] yeoy NV9YO (,) AY, ‘sye1 ¢ JO UKTI ay} Syuasoidas onjeA YoRy ‘speurtue (‘ydxq) jeuoisey “| aTaV.L No. 4, 1976] WASHINGTON AND FIFE—DIMETHYL SULFOXIDE 257 Table 2 lists the percentage distribution of “Rb per g of organ weight. It compares the percentage of “Rb found in the control and DMSO treated groups of each organ. TABLE 2. Distribution of Rb in the organs of rats after single intravenous injection. Legend: a. the upper figures in this row represent sacrifice times used by Sapirstein (1958); b. the lower figures represent sacrifice times used by us; c. the upper figure in each box represents Sapirstein’s data; d. the lower figure in each box represents our data. Percentage of **Rb Per Organ Sacrifice Time in Seconds ORncaN 3 6 9 12 16 32 64 : Qe SEO : : 30 60 300 Beart -e 7 2.7 24 2.7 2.6 : 5.28 36 26 f t 3.6 3.3 3.8 Lungs - - - - - - - - 10.4 3145 30 pace TGR: 3.6 2.9 3.8 Bec 3.1 4 68 6.8 : 17 8.1 é 3.0 AG i b 73 6.2 91 Stomach a = = Z : 3 s 0.4 07 09 : : L7 12 13 Cut 93 14.7 19.7 19.3 18.5 29,4 23.0 2 8.8 13.1 147 ‘ 14.7 12.2 15.1 Kidneys 10.5 149 143 14.4 13.7 15.8 16.1 : 97 114 138 : f 14.7 11.8 146 Thyroids : : : : : : é : 0.03 0.1 0.05 : , 0.06 0.08 0.09 Skin 3.9 72 88 91 12.5 95 12.2 : 113 23 111 : : 10.4 13.5 96 Ga 314 TOS | Aes 46.5 48.1 43.2 43.9 : 50.1 49.7 48.0 : é 43.8 48.6 44.6 Brain 0.7 08 Ol 0.1 0.1 0.1 0.1 : 0.8 08 Ol : ; 0.1 0.1 0.1 Discussion—We sought to determine the efficacy of dimethyl sulfoxide to penetrate and pass through the blood-brain barrier. Such a demonstration would indicate that DMSO might serve as a vehicle for the transport of other chemicals across the barrier. It is well known that one of the principle obstacles in the treat- ment of neural infections is the resistance encountered in transporting medi- cation into the brain. Brink and Stein (1967) reported barrier breakdown as a result of intraperitoneal injections of pemoline-C™ dissolved in DMSO. However, their interpretations were challenged by Kocsis et al. (1968) who, in analyzing Brink and Stein’s data, concluded that it was not clear that DMSO affects either the brain’s uptake of pemoline specifically, or the blood-brain barrier in general. Our results seem to corroborate Kocsis et al’s conclusion and extend it to indi- cate that, under the regime of this experiment, DMSO treatment has no effect on the blood-brain barrier (Table 1). We sought to evaluate the influence of DMSO on the capillary beds of the various organs. We wished to determine whether DMSO caused changes either 258 FLORIDA SCIENTIST [Vol. 39 in permeability or blood flow. The sacrifice intervals were subdivided into 3 phases for analytical purposes. Firstly, the 2-10 sec phase was the accumulation period. Immediately after injection, the values obtained represent transient con- centrations of **Rb. These values were artificially high in organs which received blood almost directly from the heart, such as the lungs and the brain, and prob- ably reflect portions of the injected bolus present intravascularly. The 5-10 sec segment is assumed to represent the period during which the tracer is being dis- tributed. This was a highly unstable phase and should not be used to measure blood flow to the organs. The 10 through 60 sec interval represents the second phase. It was con- sidered to be the period in which regional blood flow is measured. Only two ob- servations of possibly significant changes between the 2 groups occurred during the 10 through 60 sec interval indicating that DMSO generally affects neither the permeability nor the blood flow at the capillary beds of the organs. It was assumed that permeability changes would be manifested by significant increases in flow values at 10 sec followed by decreases at 30 sec. This would indicate an increase in diffusion to the extravascular pools. Thus the pools would fill faster under the influence of DMSO and, consequently, begin returning the labelled Rb to the vascular system faster. The 60 through 300 sec interval constituted the third phase and represents the redistribution of “Rb. Sapirstein (1956) observed that with the passage of time (1-2 min) a sufficient quantity of measuring agent will then yield false values for flow. In the case of organs with high perfusion rates, the apparent fractional flow will become falsely low; organs with low perfusion rates will yield fractional flows which are correspondingly high. LITERATURE CITED ADAMSON, J. E., C. E. Horton, H. H., CRAWFORD, AND W. L. Ayers. 1966. The effects of dimethyl sulfoxide on the experimental pedicle flap: a preliminary report. Plast. & Reconstruct. Surg. 37:105-110. Buack, D. A. K., H. E. F. Davies, E. W. Emery, AnD E. G. Wape. 1956. Renal uptake of radioactive potassium. Clin. Sci. 14:241-244. Brink, J. J., AND D. G. STEIN. 1967. Permoline levels in brain enhancement by dimethyl sulfoxide. Science 158:1479-1480. Jacas, S. W., anv D. C. Woop. 1971. Dimethyl] sulfoxide (DMSO) a status report. Clin. Med. 78(11): 21-31. AND J.H. Brown. 1969. Therapeutic potential of dimethyl sulfoxide (DMSO) in aerospace medicine. Aerospace Med. 40:75-84. KuicMan, A. M. 1965. Tropical pharmacology and toxicology of dimethyl sulfoxide (DMSO). J. Amer. Med. Assoc. 193:796-804. Kocsis, J. J., S. HaRKAway, AND W. H. VocEL. 1968. Dimethyl sulfoxide: breakdown of blood-brain barrier? Science 160:1472-1474. SaPIRSTEIN, L. A. 1956. Fractionation of the cardiac output of rats with isotopic potassium. Circu- lation Res. 4:689-692. . 1958. Regional blood flow by fractional distribution of indicators. Amer. J. Physiol. 193: 161-168. Florida Sci. 30(4): 254-258. 1976. No. 4, 1976] BOHNSACK—SPIDER CRAB 259 Conservation THE SPIDER CRAB, MITHRAX SPINOSISSIMUS: AN INVESTIGATION INCLUDING COMMERCIAL ASPECTS JAMES A. BOHNSACK Department of Biology, University of Miami, Miami, Florida 33124 ABsTRACT: Mithrax spinosissimus in Lower Florida Keys canals has an avg density of 2-4 indi- viduals larger than 6 cm carapace width per 100 sq m of canal wall; abundance increased with more and larger crevices. Tagged adults had an 18 mo molt period. Males comprised 25%, were territorial, and showed a marked increase in claw size near 8 cm carapace width. Avg crab size was estimated, 5- 10% were missing claws, and 15-20% were missing walking legs. Although loss of a claw seems to have little effect on survival, claw removal and release is not recommended for commercial use. Com- mercial exploitation does not appear sustainable at this time. IN RECENT YEARS the fishing industry for the Alaskan King Crab, Paralithodes camtschatica, has declined (Idyll, 1971), resulting in the search for other species. One suggested possibility (Bayer, in prep.) is the spider crab (Fig. 1), Mithrax spinosissimus (Lamark), common in Florida waters and about which little is known. One characteristic of potential economic significance is the herbivorous nature of this crab, based on the chela structure, suggestive of greater produc- tion from a given area compared with carnivorous crabs. A field study was initi- ated in the fall of 1973 and continued for one yr to obtain information necessary before commercial exploitation occurs. Hazlett and Rittschof (1975) made a detailed study on the behavior and movements of M.spinosissimus in a canal on the Florida Keys. Determining the full range and distribution of M. spinosissimus was not an objective of that study. Rathbun (1897, 1825) reported a geographical distribution from Carolina to the West Indies. Most crabs were observed in artificial habitats, either in holes in canal walls or under bridge pilings. Few were observed in what can be called “natural” environments. A female was observed on Looe Key Reef at night and several juveniles were seen in cavities of sponges (Speciospongia sp.) in New- found Harbor Channel. Local divers report large numbers of these crabs in shal- low “potholes” and small caves such as those found near the Content Keys, Flor- ida. My observations suggest M. spinosissimus tends to occupy rocky substrate with suitably sized holes or crevices. METHODS AND MATERIALS—Four study sites were used (Fig. 2). Site 1 was an artificial enclosure at Newfound Harbor Marine Institute (N.H.M.I.) on Big Pine Key, Florida and was used only to test tagging and claw removal tech- niques. Site 2 consisted of caves formed by erosion under the east seawall of N.H.M.I. Site 3, on the eastern side of Little Torch Key, was a 130 m section of canal wall exposed on one side to the open water of Newfound Harbor Channel. Other sections in this area lacked suitable rocky substrate and were not used. Site 4, on Little Torch Key, consisted of a series of inland finger canals, each approximately 90 m long. Most of the information came from site 4 because crabs were numerous, the area was sheltered from wind, the canal limited crab move- ments and was easy to search. 260 FLORIDA SCIENTIST [Vol. 39 ‘s | Fig. 1 Mithrax spinosissimus. A. Male, dorsal view; B. Female, dorsal view; C. Male, ventral view; D. female, ventral view. Spider crabs were sought by swimming an up and down search pattern along a canal wall. Data were recorded underwater on plastic sheets on sex, carapace width (C. W.), ventral claw length (C. L.), lost appendages, and the position and depth along the canal. Crabs were handcaught using heavy gloves and a small dip net. After tagging, each individual was returned to the location where ini- tially sighted. Crabs caught in holes were released at the mouth of the hole. When several crabs occurred in one hole (referred to as a cluster), I first at- tempted to determine the number and sex of all individuals before capturing them. If a crab could not be captured, I moved along and returned later to try again. Approximately 15% of the observed crabs (28 of 181) evaded capture. Tagging and recapture attempts occurred from September through Decem- ber 1973 and in August 1974. Tags consisted of nylon self-locking wire ties num- bered by burning near the base and by punching holes in a binomial code. Tags were placed at the base of the merus and the excess cut off. I observed that tags did not adversely affect claw movement and could not be removed. One obvious disadvantage of this tagging method was that tags were lost upon molting. Spa- ghetti tags used elsewhere (e.g., Cleaver, 1963) were not available and could not be adequately tested in time for this study. During most of the study I removed one claw underwater from every other tagged crab, just before release. Both breaking off a claw and cutting off a claw at the merus were investigated. No. 4, 1976] BOHNSACK—SPIDER CRAB 261 U.S. HIGHWAY 1 a SITE 4 ae => HANNEL jie , 3 LITTLE MY 2 TORCH : COUPON KEY BIGHT Fig. 2 Location of study sites on the Lower Florida Keys. Population sizes were estimated by two methods: a visual census and an un- biased estimate given by the following formula as described by Ricker (1958), based on Bailey’s modification (1951) of the Peterson type single census estimate. N=M(C +1) R+1 Where: N= population estimate M = number of marked crabs released C =total number of crabs captured R=recaptured crabs Population estimates apply only to site 4 because other sites lacked replicate samples or the recapture interval was excessive. The Schnabel type of multiple census estimate was considered inappropriate because of the time interval be- tween samplings and tag loss from molting. RESULTS AND Discuss1oN—Table 1 summarizes field data from initially sampled populations. Approximately 5-10% of the population had only one claw and 15-20% were missing walking legs. The largest observed crab (out of approxi- mately 300) had an 11.5 cm C. W. and 12.5 cm C. L. which was considerably smaller than the largest reported by Rathbun (1925): 17.4 cm C. W. and 18.7 cm C. L. The relationship between carapace width and total crab weight is shown in Fig. 3. Males were slightly heavier than females with the same carapace width because of larger claws. | 262 FLORIDA SCIENTIST [Vol. 39 TaBLE 1. Field data on initially sampled populations of Mithrax spinosissimus. The numbers in parentheses refer to the total number of crabs used to determine the estimate. The avg wt were based on the avg carapace width and wt curves plotted in Fig. 3. Confidence intervals were determined according to Clopper and Pearson (1934). Total Males Females Avg Claw Length (cm) 6.7 (101) 9.7 (27) 5.6 (74) Avg Carapace Width (cm) 8.9 (101) 9.6 (28) 8.6 (73) Avg Weight (gm) 333 430 290 Percent Missing a Claw 7% (103) 10% (29) 5% (74) (95% C. I.) 2%-13% 5%-28% 2%-13% Percent with One Small Claw 4% (103) 7% (29) 3% (74) (95% C. I.) 1%-10% 0%-22% 0%-10% Percent Missing Legs 17% (103) 21% (29) 15% (74) (95% C. I.) 10%-26% 10%-39% 8%-27% Cleaned crab meat from both males and females avg 15% of fresh wt. The maximum yield was 20% from a large male, compared to 25% for a king crab (Iverson, 1966). Mechanical processing could possibly increase the yield. Almost all observed crabs were larger than 6 cm C. W. The reason for not seeing smaller crabs is unknown. Eggs were observed on females from August through November. None were observed in December. Observations were not made during other months although Hazlett and Rittschof (1975) reported a few ovigerous females between January and May. Male sexual maturity may occur near 8 cm C. W. based on increased claw size (Fig. 4). Age could not be deter- mined although an 18 mo interval between molts was calculated for adults based on tag returns (Fig. 5). A total of 103 crabs were tagged of which 6 died from claw removal and 12 were tagged too late for recapture. Over 50% of the remaining crabs were re- captured at least once. The possibility that crabs were harvested from the study sites during the study was unlikely. Recapture results appear in Table 2. Crabs with a claw removed had nearly the same recapture rate as crabs with both claws, suggesting claw loss does not significantly affect survival. However, when xX 800 X MALES e FEMALES xX a — 600 — = x O x > 400 a es 200 ° 7 ot By Qe Oe seen CARAPACE WIDTH (cm) Fig. 3. Crab weight as a function of carapace width. No. 4, 1976] BOHNSACK—SPIDER CRAB 263 > MALES —— - FEMALES ------- 0 2 4 6 8 10 Carapace Diameter (cm) 12 Fig. 4. Claw size as a function of carapace width. claws were broken off, the crabs resisted autotomy and damage often occurred at the base of the coxa; 5 of 10 crabs bled to death and the other 5 moved out of sight and were not seen again. Cutting off the claw at the merus was more suc- cessful because a crab could autotomize the stub with minimum blood loss by using its remaining claw. Only one of 40 was known to die. Fight visual estimates avg 8 crabs (s.d.=3.6) per 100 m of canal wall and was considered the minimum estimate because some crabs were undoubtedly not observed. The Peterson method avg 17 crabs (s.d. = 8.7) based on 13 samples and was considered the maximum estimate because of bias from tag loss due to molt- ing and possible amputation mortality. Assuming 4 m avg depth, the calculated density was 2-4 adults per 100 m of canal wall. The standing crop was 3000-5600 g per 100 m of canal wall (7.5-14 g/m’) based on 333 g avg wt. My observations agreed with Hazlett and Rittschof’s findings (1975) that crab density was highly correlated with crevice density, and food was probably not limiting. This sug- gests that increasing the number of suitable holes could increase crab production. My observations confirmed Hazlett and Rittschof’s findings (1975) that M. spinosissimus remained in crevices during the day, moved and fed nocturnally, ate algae scraped off rocks, and usually returned to the same crevice occupied the day before. In addition, one crab was seen eating Cassiopeia sp. and crabs in aquaria ate dead meat. Table 3 gives crab composition for 151 occupied holes. Almost 55% of the crabs were in clusters of 2 to a maximum of 11 individuals. A chi-square test for goodness of fit showed male and female presence in any sized cluster was no dif- ferent than expected by chance (p <.05). However, results suggest aggression occurs between males because only one of 42 clusters had more than one male. The one exception had two males in a large partially divided cave. Possible aggression between males could account for males comprising only 25% of the sample (64 of 241) and having greater incidence of claw and walking leg losses 264 FLORIDA SCIENTIST [Vol. 39 100 (7p) oO Z 80 — ag Ln s 60 ep) {ea}