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UN aa j Sa ye j on ih iy ; - if x ij Mi 1 # * und J > | id AS t ni ; 3) y i) ‘ ] WZ \ d v od 2 4 ¥ rm ie i ie aon “y ; t i q - os } e } - ISSN: 0098-4590 Florida cientist Volume 58 Winter, 1995 Number | CONTENTS Organic Farming: An Alternative For Florida Agriculture? .........0.0..0... M.E. Swisher and P.F. Monaghan 1 Reproductive Cycle and Colonization Ability of The Mediterranean Gecko (Hemidactylulus turcicus) In South-Central Florida Walter E. Meshaka, Jr. 10 An Analysis of Fecding In The Oak Toad, Bufo quericus (Holbrook), ic Loses TE erie Bae TE eae er a Fred Punzo 16 Culturable Airborne Fungi Identified From Heating, Ventilation Air Conditioning Units (HVAC) From Home Environments Within The Someeleeessbe ta Ml OTGal REGION <551.4..2-ccsussnccbscheseeestordscoeonesettentsleaecosnedesdersess K. A. Kuehn, Robert Garrison and Larry Robertson 21 Postpartum Regression of Corpora albicantia in White-Tailed Deer ............ Ronald F. Labisky and Andreas R. Richter 25 Attempted Use of Chiral Copper (II) and Nickel(II) Catalysts For Bee imeiesiie Clhic Carpene INSEMAOM .5...).ch0sn.sscec scene sass conetersonsutenceesntoceoees Venkatraj Narayanan, Leon Mandell and Dean F. Martin 32 Vervet Monkeys In The Mangrove Ecosystems of Southeastern Florida: Eacmmnany Census and Ecological Wata:..........+.ccoec.c0seecesiecrreeceeeseeee- William R. Hyler 38 Mexico: An Alternative Source of Mercury Contamination in Florida's eM iPM ies Meas Asa wade seoanaaed sea race sesoeseaoeeuecoceeeqeisess Jay W. Palmer 44 Population Estimate of Spotted Skunks (Spilogale putorius) On a Florida LICE ISIE cdogenece sehen neuen ioe sasee te nets) AMM i am eRe eh eae a A.E. Kinlaw, L.M. Ehrhart, P.D. Doerr, K.P. Pollock and James E. Hines 48 Developmental Responses of Established Red Mangrove, Rhizophora Mangle L., Seedlings to Relative fevels of Photosynthetically Active and iiilieavolet |RASVOMBTVO TI ee a eve k carte Ng an torn ae ae ogee ee en nC Stephen M. Smith and Samuel C. Snedaker 55 2 Ze ESTE TP a day eg eel ev R. Todd Engstrom 61 ee NN ey Re as UU ek, Patricia M. Dooris 63 OSL ANE lesa Barbara B. Martin and Dean F. Martin 64 FLORIDA SCIENTIST QUARTERLY JOURNAL OF THE F'LORIDA ACADEMY OF SCIENCES Copyright© by the Florida Academy of Sciences, Inc. 1995 Editor: Dr. DEAN F. Martin Co-Editor: Mrs. BARBARA B. MARTIN Institute for Environmental Studies, Department of Chemistry, University of South Florida, 4202 East Fowler Avenue, Tampa, Florida 33620-5250 Phone: (813) 974-2374, E-Mail: Martin@chuma.cas.usf.edu THE FLoripa ScIENTIsTis published quarterly by the Florida Academy of Sciences, Inc., a non-profit scientific and educational association. Membership is open to individuals or institutions interested in supporting science in its broadest sense. Applications may be obtained from the Executive Secretary. Direct subscriptions available at $40.00 per calendar ear. : Original articles containing new knowledge, or new interpretations 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 are accepted only from members of the Academy and so papers submitted by non-members will be accepted only after the authors join the Academy. Instructions for preparation of manuscripts are inside the back cover. Officers for 1994-1995 FLORIDA ACADEMY OF SCIENCES Founded 1936 President: Dr. Patricia M. Doors Institute for Environmental Studies Department of Chemistry University of South Florida Tampa, Florida 33620-5250 President-Elect: Lisa B. BEEVER Charlotte County — Punta Gorda MPO 2800 Airport Road, A-6 Punta Gorda, Florida 33982-2411 Secretary: Mrs. MARCELLA GUITERREZ-MAYKA 701 E. River Dr. Temple Terrace, Florida 33617 Treasurer: Dr. FREDERICK B. BUONI Florida Institute of Technology 150 W. University Blvd. Melbourne, Florida 32901 Business Manager: Dr. RicHarD L. TURNER Department of Biological Sciences 150 West University Boulevard Melbourne, FL 32901-6988 [(407)768-8000, ext 8196; e-mail: Turner@fit.edu] Executive Secretary: Mrs. BETTY PREECE P.O. Box 033012 Jacksonville, Florida 32211 Indialantic, Florida 32903-0012 Tel: 407:723-6835 Program Chair: Dx. DEL DELUMYEA Millar Wilson Laboratory for Chemical Research Jacksonville University Jacksonville, Florida 32211 Published by The Florida Academy of Sciences, Inc. P.O. Box 033012 Indialantic, Florida 32903-0012 Printing by C & D Printing Company, St: Petersburg, is Florida Scientist QUARTERLY JOURNAL OF THE FLORIDA ACADEMY OF SCIENCES DEAN F. Martin, Editor BarBARA B. Martin, Co-Editor Volume 58 Winter, 1995 Number 1 Agricultural Sciences ORGANIC FARMING: AN ALTERNATIVE FOR FLORIDA AGRICULTURE?! M.E. SwisHER” AND P.F. MONAGHAN”? Home Economics Department", Anthropology Department™, University of Florida, Gainesville, FL 32611. AssTRACT: We surveyed commercial organic vegetable and citrus producers using lists provided by the Florida Organic Growers and the Organic Crop Improvement Association, two of the largest certifying agencies currently active in the state. Production practices used by these growers are described, and we examine whether organic nutrient and pest management systems represent viable alternatives for Florida agriculture. Our discussion focuses on the availability and costs of non-synthetic nutrients, issues of scale, and the role of geographic isolation in protecting organic systems. The potential benefits and problems of organic production are considered. SoME perceive of organic agriculture as a sustainable alternative to conventional agricultural production because organic production does not depend on synthetic inputs. Florida-certified organic producers, for example, must avoid the use of synthetic fertilizers and pesticides and use instead organic manures, green manures and cultural and biological pest control techniques. While we do not argue that a purely organic system of production is either desirable or feasible in Florida, other studies show that organic production systems are less energy- and synthetic input- intensive than some conventional systems (Berardi, 1978; Craumer, 1979; Klepper et al., 1977). Therefore, we conducted a survey of commercial organic vegetable and citrus producers in Florida to identify organic production practices, especially nutrient and pest management techniques, that could be incorporated into the state’s conventional production systems. The survey documented impressive growth in the number of commercial organic farmers in the past ten years. Organic farmers are using diverse land management practices, often combining 10 to 30 different crops and using rotational fallows and leguminous cover crops. Most are small businessmen and women with 'Florida Journal series no. r-04141 2 FLORIDA SCIENTIST [VOL 58 farms and groves under 50 acres. Most of the producers that we spoke with were part- time farmers who had to be devoted entrepreneurs to gain a niche in the lucrative organic market of local health food stores, restaurants, and out-of-state brokers that supply organic produce nationwide. Like most producers who lie outside the mainstream o fagriculture, either because they produce a non- traditional commod- ity or because they farm in a non-traditional way, the mainstream agricultural support system often does not serve their needs. For example, organic producers may need special equipment or organically based weed control mechanisms, but because of the small market that they represent, the agricultural support industry usually pays relatively little attention to these needs. As a result, they struggle to find nutrient sources and experiment with different enterprise combinations on their small farms. Many acres of once-abandoned orange groves are being converted to organic practices of fertilizing and controlling pests and a handful of growers are starting new organic groves using standard commercial technology. There are several large commercial citrus producers in the state that have taken notice and are also experimenting with the organic market. Our survey raised several issues about how much organic producer have to offer conventional input intensive farms in the state. We conclude that organic production techniques have potential for specific geographic regions of Florida, for non- traditional crops and for small farmers. However, organic production cannot be compared to the state’s multibillion dollar vegetable and citrus industries unless a wider agricultural system is considered. We detail the constraints to widespread adoption of organic techniques in nutrient and pest management. A Perspective From Florida—Much of the research done on ecologically sustainable agriculture has focused on relatively low input systems, often based on livestock or agronomic crop production. Examples include the large body of research on reduced tillage methods (Hefferman and Green, 1986; Hendrix, 1987; House and Brust, 1989) and integrated pest management (Altieri et al., 1983; Clancy, 1 986; Edwards et al., 1988: Lockeretz, 1991; Pimentel et al., 1989). Much of this work focuses on agronomic crops such as cotton, soybeans, and corn. A considerable portion of the research about organic agricultural production has focused on the same crops and similar production systems, particularly mixed crop and livestock systems (Berardi, 1978; Dabbert and Madden, 1986; Klepper et al., 1977; Lockeretz et al., 1984: Pimentel et al., 1983). This research is of limited value to Florida, where citrus and vegetable sales are a $2.6 million industry. Both vegetable crop and citrus production depend on high inputs of labor, fossil fuel energy, and agrichemicals to compensate for poor soil fertility on Florida’s sands and the pest problems associated with the humid subtropics. Florida’s agricultural production must compensate for seasonal water scarcity, poor native soil fertility and the variety of pest problems common in the humid subtropics. Although average precipitation is high, most of Florida’s soils are sands. Their high porosity, combined with the high evapotranspiration rates experienced during the warm months, makes Florida a water-deficit environment for growers of horticultural crops and citrus during the warm months. During the cool season No. 1 1995] SWISHER AND MONAGHAN—ORGANIC FARMING 3 production cycle, rainfall is low. Conventional growers have responded to water quality and water supply regulations by switching to low volume irrigation and use of pest scouting, often carried out by professional consultants (Swisher and Bastidas, 1994). The low native fertility of Florida’s sandy Inceptisols and Ultisols require high nutrient application rates. While agricultural production on the state’s Histosols (mucks) is economically important, these soils represent a small percentage of the total agricultural acreage in the state. Further, some agricultural lands on the muck soils have been purchased by the state of Florida for wetlands restoration in the past decade. Florida’s subtropical climate, particularly in the major vegetable and citrus producing regions in the southern peninsula contributes to insect, disease, and weed problems that necessitate applications of ethyl bromide, herbicides, fungicides, and other pesticides for each crop. Because organic production eliminates the use of synthetic materials, we felt that the incorporation of some organic production techniques into conventional systems offered one possible avenue for reducing the potential environmental impacts from agrichemicals. Organic production would utilize animal wastes, which helps resolve the disposal problem of the state’s poultry and dairy farmers. Some studies (Berardi, 1978; Johnson et al., 1977; Klepper et al., 1977; Pimentel et al., 1983) have shown that non-renewable energy use is lower on organic than conventional farms. Others argue that use of organic soil amendments improves soil qualities such as tilth and moisture retention, reduces plant parasitic nematode populations, and reduces erosion (Buchanan, 1983; Heichel, 1978; Lockeretz et al., 1981; McGrady, 1992; Shennan, 1992). Organic Nutrient Management Techniques—The most common sources of nutrients used by organic producers in the survey were animal manure (mainly from broiler farms and some dairies) and fish emulsion with kelp or seaweed. Bagged organic fertilizers, most containing poultry manure, are used by many Florida organic farmers, particularly the producers of high value vegetable crops (Swisher et al., 1994a; Swisher et al., 1994b). In terms of quantity applied, chicken manure is the most commonly used nutrient source, either composted from nearby broiler farms or processed and bagged or liquefied for injection. Fish emulsion and kelp or seaweed mixes are also used by almost all growers. Although they account for a small quantity of fertilizer applied, due to their concentrated nature, they are sprayed on approximately 250 ha, sometimes two to three times per crop. Among organic citrus producers surveyed, chicken manure is also the preferred fertilizer source. Over three-fourths, 79%, used chicken manure as their primary nutrient source. Seventy- one percent of all growers interviewed sprayed fish emulsion on their citrus. Despite the potential advantages from organic nutrient sources, conventional vegetable producers have yet to utilize a significant amount of manure while conventional citrus producers have been quicker to increase use of organic nutrient sources. Compared to the research base for inorganic nutrient sources, relatively little research concerning the effects of organic soil amendments on soil physical and chemical properties has been conducted under the bio-physical conditions typical of 4 FLORIDA SCIENTIST [VOL 58 Florida. Several studies have been conducted which examine agronomic crop and forage response to manure application (Gallaher et al., 1994). Another advantage from the use of organic nutrient sources for Florida would be reducing the problem of manure disposal that the state’s animal producers face. The dairy industry is a good example. Florida dairies are large, averaging 500 cows per herd. Many dairy producers, particularly in the Lake Okeechobee watershed, face severe constraints in disposing of manure. It therefore appears that there is a good opportunity to solve two problems-nutrient supply and manure disposal—by increasing use of manure as a nutrient source. However, the nutrient sources and vegetable and citrus production areas do not necessarily coincide geographically. For example, much of Florida’s broiler production is located in North Florida, where there is no citrus production and limited vegetable production. Therefore, not all of the nutrients that are available in the state are economically viable as a source of nutrients for vegetable or citrus producers. The preferred source of organic soil amendments is broiler manure because it has a relatively high nutrient content, particularly nitrogen, the major limiting nutrient for most of Florida agriculture, and because itis a relatively dry manure, easy to handle and prepare for field application. However, Florida’s broiler manure is already scarce. Our survey showed that the cost of chicken manure has increased greatly in recent years. One chicken manure vendor indicated, for example, that his sales have increased eighteen-fold over the past eight years. Other manures are generally lower in nutrient content and harder to apply because of their high moisture content. The organic farmers interviewed often said that organic nutrient sources improve overall soil “health,” including enhancing biological activity in the soil and increasing soil organic matter content, with resulting improvements in water retention capacity. They also point out that the nutrients in organic sources are released slowly, reducing flushes of nutrients into the soil-moisture complex. The degree to which organic matter additions actually contribute to increase long term soil organic matter content is debatable. Swisher’s (1982) research in Costa Rica, for example, showed that soil organic matter content 90 days after application was not affected by application of compost, most probably due to high rainfall regimes and high temperatures leading to rapid oxidation of the organic addition to the soil. Very little research has been conducted about the effects - either positive or negative - of organic soil amendments on pests such as weeds, nematodes, and soil borne plant pathogens. For example, tomato growers can invest up to $4,000 per acre to produce a crop and are therefore unwilling to risk using technologies that are not well researched. Fossil fuel for fertilizer accounts for 11% of the total energy used in conventional citrus groves (Fluck, 1992a) and slightly over 7% (Fluck, 1992b) of all energy used in Florida vegetable production. Theoretically, organic production should save virtually all of this fossil fuel energy input. The actual energy savings is somewhat less because of the long distances that manure and other organic soil amendments are moved, their bulky nature, and the number of trips across the field required to apply them. No. 1 1995] SWISHER AND MONAGHAN—ORGANIC FARMING 5 The use of organic amendments may offer more promise for citrus than for vegetable production, and in fact citrus producers purchase much of the broiler manure available in Florida. First, the soil in citrus groves remains relatively undisturbed, enhancing the probability of soil organic matter accumulation. Further, a perennial tree crop is less sensitive than a short season vegetable crop to the time of fertilizer application. Therefore, citrus crops are better able to utilize nutrients released over an extended period of time than are vegetable crops. Some conventional citrus growers in Florida are using organic nutrient sources, also suggesting that this production technique may have considerable potential for the state’s citrus industry. Organic Pest-Management Techniques—Use of synthetic pesticides is under increasing restrictions both nationally and in Florida and the potential environmental damage from pesticides has been well documented (Pimentel, 1980). Integrated pest management, long an important research and extension thrust in Florida, represents a move away from reliance on pesticide application, particularly calendar application. Many Florida growers already apply the principles of integrated pest management (Swisher and Bastidas, 1994). It seems logical, therefore, that organic production techniques in the area of pest management would be particularly attractive to conventional producers. In our survey, pest management problems, particularly disease problems, were not viewed as serious by most organic growers. Even insect pests, though frequently mentioned, were not seen as a serious production problem by most of the producers who were interviewed. Most indicated that they “live with” insect pests. Diseases were mentioned, but often no specific management practices were used to control them, and nematodes were rarely viewed as an important problem. Few of the growers interviewed seemed to feel pests significantly reduced either yield or earnings. Avoidance was a major strategy used by organic producers, e.g., they plant vegetable crops that suffer relatively few pest problems. Organic growers repeatedly indicated that they could not raise tomatoes, particularly in the fall, due to insect pest and disease problems. Similarly, bell peppers, another very important Florida vegetable crop for conventional producers, accounted for very little of the organic acreage. We conclude that care should be used in making assumptions about the applicability of organic methods to major vegetable crop production systems. Comparative studies are needed, in which the same major vegetable crops are grown under the same bio-physical conditions. Multi-year studies are needed to measure the fluctuations in pests from year to year and scale needs to be included in the research agenda. Florida represents a particularly good opportunity for such studies because of the sub-tropical climate and associated insect pest and disease management problems cited by conventional growers. Our results also showed that organic vegetable farms lie outside the major vegetable producing regions in Florida. Further, most were geographically isolated from other farms producing the same or similar crops. Our review of the literature describing research on organic vegetable farms fails to reveal the degree to which the 6 FLORIDA SCIENTIST [VOL58 research sites were isolated from agricultural systems producing the same crops. We can find no comparative studies in which geographic location was used as a predictive variable for the occurrence of diseases and insect pests. Much more research is needed in Florida to understand the dynamics of pest management under organic production. In order to convince major agribusiness farmers to adopt organic pest management strategies, we will need to be able to predict pest behavior under a wide range of conditions. Sweet potato whitefly provides an example of the potential for disaster in these large, continuous production, contiguous cropping systems. Until we can assure growers that control of major pests such as this one is possible without the use of synthetic pesticides, the ae for adopting organic pest management strategies will be limited. Other Production Issues—Our study originally focused almost solely on production questions. Our original concerns were with finding environmentally sound alternatives to high-input vegetable and citrus production techniques. Examination of the production data, as well as discussions with organic producers about the problems that they face, raised additional, broader questions regarding the sustainability of both conventional and organic alternatives in Florida. Organicv egetable production is even more labor intensive than Florida vegetable production generally. This is largely due to the need to hand-weed. The labor force that would be required to substitute manual control for all herbicides and soil fumigants used in Florida would be very high. Labor scarcity is a problem for some organic producers, especially securing a sufficient labor force in a timely fashion. Conventional production systems depend on a migrant labor force, often immigrants. and have had to meet increasingly strict federal regulations regarding employment of temporary crews. Cost is another consideration. an of the biggest concerns with NAFTA for Florida vegetable producers was its potential for reducing the competitiveness of Florida production because of lower wages for agricultural labor in Mexico. Citrus, except at harvest, has a lower total labor demand than vegetable, again making the organic alternative potentially more attractive in the citrus industry. Increased management intensity is another potential objection to organic management approaches for conventional producers. Current production systems in Florida are competitive partly because they produce a large volume, partly because they are highly efficient, and because production i is possible during periods of the year when the other continental US producing regions are inactive in the market. Florida tomato yields, for example, average 1350 cartons (25 pounds per carton) per acre in the state’s three major aaa areas, compared to only 880 cartons per acre in Sinaloa, Mexico. Because of high yields, despite the fact that Florida production costs are anywhere from $900 to $2,000 per acre higher than those in Sinaloa, per carton production costs are nearly the same (Florida Grower and Rancher, 1992). Florida’s efficiency depends on effective management. Management time per unit areais reduced by adopting uniform production practices. Costs are lowered by reducing the number of skilled managers per production unit. Florida’s organic vegetable producers, on the other hand, use very complex No. 1 1995] SWISHER AND MONAGHAN—ORGANIC FARMING 7 management systems, applying a high level of management input per unit of production. Production practices are tailored to the requirements of small production units, often only a few acres in size. Conventional farms are managed, on the contrary, to produce uniform growing conditions. We found, for example, only two organic vegetable producers who use plastic mulch. Conventional tomato producers, regardless of size, use mulch (Swisher and Bastidas, 1994), which produces a uniform environment that reduces nutrient leaching, maintains soil moisture more uniformly, and helps prevent weed development. Further, a large number of crops are often raised on a single organic farm. There are several reasons for this, but polyculture appears to be related to pest management and small farm marketing. Again, management costs could increase significantly on large scale production units if they attempted to utilize this polyculture approach. The fresh vegetable market is a highly competitive one. Profit margins can be low, part of the reason why Florida producers are so concerned about the potential impact of reducing tariffs on imported vegetables under NAFTA. Organic producers simply do not compete in these markets. Rather, they are filling specialty markets with higher value and lower demand. Further, organic growers often do not have to meet strict grading standards for their products. Our analysis shows that production costs are similar for the same vegetable. Conventional and organic systems, for example, have nearly the same production costs for bush beans and summer squash. If yields were lower in organic systems, on the average, it is clear that Florida could not maintain its competitive position in the market relying on organic production techniques. Wide-scale adoption of organically produced products also implies major changes on the part of the US consumer. Consumers today expect a uniform product, free of blemishes and with a long shelf life. Organically produced vegetables may not meet consumers’ standards. Consumers also expect year-round availability of all major vegetable crops. Organic systems depend much more so than conventional systems on favorable environmental conditions for their production. Again, tomatoes provide an example. Conventional vegetable farmers in Florida can produce a fall tomato crop because they use synthetic pesticides to combat pests such as whitefly, which develop high population levels during the long, hot, humid Florida summer. Organic vegetable farmers simply avoid planting tomatoes in the fall. We conclude that changes in consumer preferences would be a major factor determining the degree to which organic production could be adopted on a large scale by Florida’s vegetable industry. Conc.Lusions—Agriculture in Florida has grown into an input intensive, multibillion dollar industry but it is facing a challenge from foreign producers, competition for water and strict regulation of pesticide and fertilizer use. Some would argue that Florida vegetable production is inherently non-sustainable because of its high dependence on fossil fuel energy and synthetic inputs. Often, organic production is posed as a “sustainable” alternative toinputintensive conventional systems. We conclude that the debate over organics as an alternative to current production needs to be redefined. It is not a question of either one system or the other. Past 8 FLORIDA SCIENTIST [VOL 58 research has tended to focus on comparing specific characteristics of organic and conventional production systems. However, organic production cannot be posed as a replacement for traditional, industrial agriculture without addressing the issues of scale of production, the location of services, shipping points, labor and consumer demand. Organics have developed to fill a niche, just like tomatoes in the poor soils of peninsular Florida. Clearly organic techniques have some promise in specific areas such as citrus and “nontraditional crops”, in specific geographic regions of the state and for small farms. Future research, however, must focus on meso and macro-scale phenomena and consider the production system as a component in a the totality of the overall agricultural production system. Questions such as the role of geographic isolation, avoidance strategies, and other issues should be addressed at these larger scales. ACKNOWLEDGEMENTS—This survey was supported by funding from the Florida Energy Extension Service. We also wish to thank the Florida Organic Growers and the Organic Crop Improvement Association for their assistance in providing us with lists of organic producers. Finally, we want to thank all of the growers who helped us with the survey. LITERATURE CITED AutierI, M.A., D.K. LETOURNEAU AND J.R. Davis. 1983. Developing sustainable agroecosystems. Bioscience 33(1):45-49. Berarbl, G.M. 1978. Organic and conventional wheat production: examination of energy and econom- ics. Agroecosys. 4:367-376. BucuaNnaNn, M.A. 1983. The effects of inorganic and organic soil amendments on nitrogen cycle components and nitrogen distribution in broccoli crop systems. Masters Thesis, University of California at Santa Cruz, Biology Department. Ciancy, K.L. 1986. The role of sustainable agriculture in improving the safety and quality of the food supply. Amer. J. Altern. Agric. 1(1):11-17. CrauMER, P.R. 1979. Farm productivity and energy efficiency in Amish and modern dairying. Agric. Environ. 4: 281-299. DasBERT, S. AND P. MADDEN. 1986. The transition to organic agriculture: a multi-year simulation model of a Pennsylvania farm. Amer. J. Altern. Agric. 1:99-107. Epwarps, C.A., B.R. STINNER AND N. CREAMER. 1988. Pest and disease management in integrated lower input/sustainable agricultural systems. Pp. 1009-1016. : Proc. British Crop Protection Conv., Vol. 3. FLoriDA GROWER AND RANCHER. 1992. Mexico versus Florida. Pp. 12-13. In: Florida Grower and Rancher. Fiuck, R.C. 1992a. Energy for Florida Tomatoes. Florida Energy Extension Service, Cooperative Extension Service, University of Florida, Gainesville, FL. 2 pp. . 1992b. Energy for Florida Oranges. Florida Energy Extension Service, Cooperative Extension Service, University of Florida, Gainesville, FL. 2 pp. GALLAHER, R.N., H.H. VANHorn, JR. AND T.A. Lanc. 1994. Nitrogen and phosphorus in waste-water from nine spray-fields on s even north Florida dairies. Agron. Res. Report AY-94-01, Agronomy Department, University of Florida, Gainesville, FL. HEFFERMAN, W.G. AND G.P. GREEN. 1986. Farm size and soil loss: prospects for a sustainable agriculture. Rural Soc. 51(1):31-42. HEICHEL, G.H. 1978. Stabilizing agricultural energy needs: role of forages, rotations and nitrogen fixation. J. Soil Water Conserv. Nov/Dec.:279-282. HENnpriIx, P.F. 1987. Strategies for research and management in reduced-input agroecosystems. Amer. J. Altern. Agric. II(4):166-172. House, G.J. AND G.E. Brust. 1989. Ecology of Low-input, no-tillage agroecosystems. Agric. Ecosys. Environ. 27:331-345. Jounson, W.A., V. STOLTZFUS AND P. CRAUMER. 1977. Energy conservation in Amish agriculture. Science 198:373-378. No. 1 1995] SWISHER AND MONAGHAN— ORGANIC FARMING 9 KLEpPER, R., W. LOCKERETZ AND B. COMMONER. 1977. Economic performance and energy intensiveness on organic and conventional farms in the corn belt: a preliminary comparison. Amer. J. Agric. Econ. 59:1-11. Lockeretz, W., G. SHEARER AND D. Kon. 1981. Organic farming in the corn belt. Science 211:540-547, ,G, SHearer, D.H. Koni AnD R.W. KLEpper. 1984. Comparison of organic and conven- tional farming in the corn belt. Pp. 37-48. In: Bezpicek, D.F. et al. (eds)., Organic farming: current technology and its role in a sustainable agriculture. Amer. Soc. Agron., Madison. . 1991. Information requirements of reduced-chemical production methods. Amer. J. Altern. Agric. 6(2):97-102. McGarapy, J. 1992. Sustainable vegetable production: introduction to the colloquium. Hort. Sci. 97(7):735-736. PIMENTEL, D. 1980. Environmental and social costs of pesticides: a preliminary assessment. Oikos 34(2):126-140. , G.J. BEarD AND S. Fast. 1983. Energy efficiency of farming systems— organic and conventional agriculture. Agric. Eco sys. Environ. 9:359-372. , T.W. Cu.iiney, I.W. Butter, D.J. REINEMANN AND K.B. BECKMAN. 1989. Low-input sustainable agriculture using ecological management practices. Agric. Ecosys. Environ. 27:3-24. SHENNAN, C. 1992. Cover crops, nitrogen cycling and soil properties in semi-irrigated vegetable production systems. Hort. Sci. 27(7):749-754. SwisHER, M.E. 1982. An investigation of the potential for the use of organic fertilizer on small, mixed farms in Costa Rica. Ph.D. Dissertation, Geography Department, University of Florida, Gainesville, FL. 261 pp. , AND E. Bastipas. 1994. Florida’s tomato growers: are they moving toward sustainability? Paper presented at the 58th Annual Meeting of the Florida Academy of Sciences, Tallahassee, Fl, March 26-28, 1994. , P.F. MONAGHAN AND J. FERcuson. 1994a. A profile of Florida’s commercial organic citrus growers. Florida Cooperative Extension Service, Energy Extension Service, University of Florida, Gainesville, FL. , P.F. Monacuan, D. SCHUSTER AND G.A. BrRINEN. 1994b. A profile of Florida’s organic vegetable farmers. Florida Cooperative Extension Service, Energy Extension Service, University of Florida, Gainesville, FL. Florida Scient. 58(1): 1-9. 1995. Accepted: September 2, 1994. 10 FLORIDA SCIENTIST [VOL 58 Biological Sciences REPRODUCTIVE CYCLE AND COLONIZATION ABILITY OF THE MEDITERRANEAN GECKO (HEMIDACTYLUS TURCICUS) IN SOUTH-CENTRAL FLORIDA WALTER E.. MESHAKA, JR. Archbold Biological Station, P.O. Box 2057, Lake Placid, Florida 33852 Apstract: The reproductive cycle of the Mediterranean gecko was studied from one site in south- central Florida. Egg laying took place between May and August. Sexual maturity of both sexes was possible within the first year at similar body sizes. Sex ratio of the annual sample was 1:1. Comparisons with Texas and Louisiana populations revealed great overlap in reproductive cycles despite geographic differences. The seasonally restricted reproductive cycle of this species in southern Florida may have contributed to a decline in its distribution and abundance as a result of competition with other recently established and rapidly dispersing hemidactylines that exhibit greater fecundity. HEMIDACTYLUS TURCICUS was first recorded from Florida on Key West, Monroe Co. by Fowler (1915) and later by Barbour (1936) in Miami, Dade Co. Like its initial introduction, the subsequent dispersal of this species through Florida and parts of the south-eastern/south-central United States (Conant and Collins, 1991) has been facilitated by humans (Davis, 1974; Wilson and Porras, 1983; Conant and Collins, 1991). Although H. turcicus was once locally common on Key West and Stock Island (Duellman and Schwartz, 1958), Meshaka and co-workers (1994c) reported its almost complete replacement by H. mabouia, a more recent invader of southern Florida. Similarly, on southern mainland Florida, H. garnotii and H. mabouia occur in large numbers and their success may be related to the apparent exclusion of H. turcicus (Butterfield et al., 1993; Meshaka, 1994; Meshaka et al., 1994a). Like H. garnotii, H. mabouia and the most recent hemidactyline invader of the lower Florida Keys, H. frenatus, are capable of continuous reproduction (Meshaka, 1994; Meshaka et al., 1994b & c). Populations of H. turcicus studied in Texas (Selcer, 1986) and Louisiana (Rose and Barbour, 1968) exhibit a highly seasonal reproductive cycle. King (1958) reported the same pattern from a population he observed in north- central Florida. The reproductive cycle of H. turcicus from one site in south-central Florida was examined in order to further examine geographic differences in its reproductive pattern and to compare its fecundity with that of recently introduced and rapidly expanding congeners in Florida. MeETHODs—From February 1993 to January 1994, one 0.5-hr visit was made each month to the same location in Lake Placid, Highlands Co., Florida. The three buildings of this site border the southeast corner of Lake Istokpoka on county road 621 and is surrounded on all sides by agricultural fields. The cement block and wood buildings were built in the 1950s. Artificial lighting provided a mosaic of light intensities including no light at all. Throughout the wet season (May-October), insects abounded at this site. I collected all geckos possible during two searches around the main packing house and the adjacemt bunk house and latrine. Geckos were frozen within 2 hrs of capture, fixed in formalin the next day, and No. 1 1995] MESHAKA—REPRODUCTIVE CYCLE OF THE MEDITERRANEAN GECKO 1] % TESTIS LENGTH 73 6-4 T =e eal T ! FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC JAN MONTH Fic. 1. Seasonal variation in testis length expressed.as a % of the snout-vent length of males of Hemidactylus turcicus from south-central Florida from February 1993 to January 1994. finally stored in 70% ETOH. Within one week of storage, specimens were dissected for examination of gonads. Coiled epididymis and enlarged testes of males and presence of yolking follicles in females indicated sexual maturity. Measurements of left testis length of males, diameter of follicles of females, and snout-vent length (SVL) were taken to nearest 0.1 mm with use of a vernier calipers. Mean values are followed by + 2 standard deviations. All specimens were deposited in the United States National Museum (USNM). REsuLts—Mean SVL of 75 adult males was 49.1 + 4.29 mm (range = 39.4 - 79.0). Testis length exhibited seasonal variation in size (Fig. 1) and was greatest during the dry season (November-April). Mean SVL of 66 adult females was 50.7 + 4.29 mm (range = 43.3 - 57). Shelled eggs (X= 9.54 + 0.68 mm; range = 8.4-10.6; N= 15) occurred in females from May through August (Fig. 2), and counts of follicles > 1.0 mm revealed that within a season females were capable of laying 1 to 5 clutches (X =a.on + 10,98: N= 57). Sexual maturity for both sexes could be attained in less than one year (Fig. 3). Both sexes achieved sexual maturity at similar body sizes, and mean adult body size of both sexes did not differ significantly (P > 0.05) using a t-test. Although more males than females were collected, a chi square test indicated that the sex ratio of the total sample did not differ (P > 0.05) from 1:1. 12 FLORIDA SCIENTIST [VOL 58 DIAMETER OF OVA Ol OVA m SHELLED EGGS Fic. 2. Seasonal variation in diameter (mm) of ova in Hemidactylus turcicus from south-central Florida from February 1993 to January 1994. Open squares indicate yolked ovarian follicles. Closed squares indicate shelled eggs. First hatchlings were collected in August (Fig. 3), however, the distribution of sizes of immatures from August was suggestive of a hatchling emergence in July, and perhaps after the mid June collection. Ninety-six immatures were collected and represented 41% of the total sample of geckos taken from this effectively isolated site. Discussion—The reproductive cycles of both sexes were seasonal in this population. Fertility of males, as determined by enlarged testis length, preceded ovarian development and was suggestive of spring mating. No gravid females were detected after August, and the condition of follicles indicated cessation of egg laying in that month. These findings agreed with King’s (1958) observations of seasonal reproduction (April-August) in north-central Florida and indicated no variation in reproductive season between geographically disparate populations in Texas (Selcer, 1986) and Louisiana (Rose and Barbour, 1968). In Lake Placid, H. turcicus and H. garnotii were in syntopy; however, the age of the colonies and relative abundance of both species appeared to be very different from one another. A specimen of H. garnotii in the vertebrate collection at Archbold Biological Station (ABS 869) was collected from Lake Placid in 1981 and documents its presence in Highlands County. Colonization by H. garnotii in lake Placid probably No. 1 1995] MESHAKA—REPRODUCTIVE CYCLE OF THE MEDITERRANEAN GECKO 13 “hen i ieee” Haale pea = ‘a = = = 5 | @ =e @ Fos fb fe) = ce a. es a : i 2 & (| f oe S mm 1 sy Is 5 ~«” «x 8 *K x >K adr ine te, SK SK Ror Gay ity * x : 3K “x *K betel eo segs dulcis . SK 3K foi Mi teary 2 aS ES aK Spapiaas > SK 2 3 4 5 6 7 8 9 10 11 12 1 MONTH * IMMATURE @™@ MALE OO FEMALE Fic. 3. Snout-vent length (SVL) in mm of males (solid square), females (empty square), and immatures (asterisk) from south-central Florida from February 1993 to January 1994. took place in the early to mid 1980s (Layne, 1994). Despite recent colonization, H. garnotii was very numerous in Lake Placid. During this study I found at least one or two and sometimes up to 20. H. garnotii on buildings seemingly everywhere in town. Unlike H. garnotii, the presence of H. turcicus in Highlands Co. was unknown prior to this study (Wilson and Porras, 1983; Conant and Collins, 1991), but colony age for H. turcicus of Lake Placid could be approximated by comparison to other records and by the nature of their dispersal. McCoy’s (1971) early record in St. Petersburg (Pinellas Co.), records from Tampa (Hillsborough Co.) in the early 1960s (Woolfenden, 1994), and King’s (1958) record in Gainesville (Alachua Co.) corrobo- rate discontinuous and historical presence of this species in Florida. Broward Co. (Wilson and Porras, 1983), St. Lucie Co. (Myers, 1978a), Indian River Co. (Myers, 1978b), Duval Co. (Meylan, 1977), and St. Johns Co. (Wise, 1993) records all follow US-1 along the east coast and likely represent colonies as old as the colonies I detected in 1993 which followed US-27 and SR-70 (Records- Glades Co., Moorehaven, USNM 2178235: Osceola Co., St. Cloud, USNM 217449-450: Reports- Okeechobee Co., Okeechobee; Hendry Co., Clewiston). These records and reports verify the scattered and haphazard pattern of colonization often associated with man-assisted transport along trucking routes (Davis, 1974; Godley et al., 1981) and suggest widespread presence longer than officially recognized. Indeed, much of the present- day range of H. turcicus in Florida, including Lake Placid, may have already been 14 FLORIDA SCIENTIST [VOL 58 established during the early 1960s, a time which coincided with the colonization and expansion of H. garnotii through southern Florida (Wilson and Porras, 1983). The population of H. turcicus was large at the study site and appeared to be growing, however, H. turcicus was nearly absent at the only other three buildings in Lake Placid where it was found. The virtual replacement of the once ubiquitous H. turcicus on the Lower Florida Keys by H. mabouia (Meshaka et al, 1994c), in southern mainland Florida by H. garnotii and H. mabouia (Meshaka et al., 1994a), and in Clearwater, Florida (Lewis, 1994) by H. garnotii may have been hastened by the greater fecundity of both species (Meshaka, 1994; Meshaka et al., 1994b). Like H. garnotii of extreme southern Florida (Meshaka, 1994), H. garnotii observed and collected in Lake Placid during this study exhibited continuous reproduction. If competition is playing arole in species replacement of exotic hemidactylines in southern Florida,.the same phenomenon may be at work in south- central Florida where H. turcicus lacked the high fecundity and reproductive versatility of other recently colonizing and rapidly expanding congeners. ACKNOWLEDGMENTS—John W. Fitzpatrick, Executive Director of Archbold Biological Station, kindly made this project possible. James N. Layne’s comments on an earlier draft greatly improved the quality of this manuscript. LITERATURE CITED Barsour, T. 1936. Two introduced lizards in Miami. Copeia. 2:113. BUTTERFIELD, B.P., J.B. HAUGE AND W.E. MEsnaka, JR. 1993. The occurrence of Hemidactylus mabouia on the United States mainland. Herpetol. Rev. 21:111-112. Conant, R. AND J.T. Cotins. 1991. A field guide to reptiles and amphibians of eastern and central North America. Houghton Mifflin Company, Boston, MA. 450 pp. Davis, W.K. 1974. The Mediterranean gecko, Hemidactylus turcicus, in Texas. J. Herpetol. 8:77-80. DUELLMAN, W.E. AND A. ScHwartz. 1958. Amphibians and reptiles of southern Florida. Bull. Florida St. Mus. 3:181-324. Fow er, H.W. 1915. Cold-blooded vertebrates from Florida, the West Indies, Costa Rica, and eastern Brazil. Proc. Acad. Natur. Sci. Philadelphia 67:244-269. Gop ey, J.S., F.E. Lourer, J.N. Layne anp J. Rossi. 1981. Distributional status of an introduced lizard in Florida: Anolis sagrei. Herpetol. Rev. 12:84-86. Kinc, F.W. 1958. Observations on the ecology of a new population of the Mediterranean gecko, Hemidactylus turcicus in Florida. Quart. J. Fla. Acad. Sci. 21:317-318. LaynE, J.N. 1994. Researcher, Archbold Biological Station, Lake Placid, Florida, Pers. Commun. Lewis, J. 1994. Naturalist, St. Petersburg, Blonde, Pers. Commun. McCoy, C.J. 1971. New records: Hemidactylus turcicus. Herpetol. Rev. 3:89. Mesuaka, W.E. JR. 1994. Reproductive cycle of the Indo-Pacific gecko, Hemidactylus garnotii in south Florida. Florida Scient. 57:6-9. B.P. BUTTERFIELD AND J.B. Hauce. 1994a. Hemidactylus mabouia as an Beoblished member of the Florida herpetofauna. Herpetol. Rev. B.P. BuTTERFIELD AND J.B. Hauce. 1994b. Reproductive characteristics of Hemidactylus mabouia in southern Florida. Herpetological Natural History. (In Press). B.P. BUTTERFIELD AND J.B. Hauce. 1994c. Hemidactylus frenatus established on the Lower Florida Keys. Herpetol. Rev. (In Press). MeyiaNn, P. 1977. Geographic distribution: Hemidactylus turcicus. Herpetol. Rev. 8:39. Myers, S. 1978a. Geographic distribution: Hemidactylus turcicus. Herpetol. Rev. 9:62. ________. 1978b. Geographic distribution: Hemidactylus turcicus. Herpetol. Rev. 9:107. Rose, F.L. anp C.D. Barzsour. 1968. Ecology and reproductive cycles of the introduced gecko, Hemidactylus turcicus, in the southern United States. Amer. Mid]. Natur. 79:159-168. No. l 1995] MESHAKA—REPRODUCTIVE CYCLE OF THE MEDITERRANEAN GECKO 15 Setcer, K.W. 1986. Life history of a successful colonizer: the Mediterranean gecko, Hemidactylus turcicus, in southern Texas. Copeia 4:956-962. Witson, L.D. AND L. Porras. 1983. The impact of man on the south Florida herpetofauna. Special Publ. No. 9. Univ. Kansas Mus. Nat. Hist. Lawrence, KS. Wise, M. 1993. Geographic Distribution: Hemidactylus turcicus. Herpetol. Rev. 29:109. WOoLFENDEN G.E. 1994. Department of Biology, University of South Florida, Tampa, FL., Pers. Commun. Florida Scient. 58(1): 10-15. 1995. Accepted: August 27, 1994. 16 FLORIDA SCIENTIST [VOL 58 Biological Sciences AN ANALYSIS OF FEEDING IN THE OAK TOAD, BUFO QUERCICUS (HOLBROOK), (ANURA : BUFONIDAE) FRED PUNZO Department of Biology, University of Tampa, 401 W. Kennedy Blvd., Tampa Florida 33606 -1490, USA Asstract: Although Bufo quercicus is a generalized predator that accepts a wide variety of insects and spiders, it exhibits a preference for certain prey types. In adult toads, 69.8 - 84.0 % of the stomachs examined contained ants, depending on the season, followed by spiders (54.2 - 56.1 %), termites (24.6 - 26.5 %) and carabid beetles (24.6 - 36.1 %). The diet of juveniles is dominated by collembolans (87.3 - 91.3 %), ants (87.0 - 92.5 %), spiders (44.3 - 49.3 %) and mites (22.2 - 25.3 %). Mites and collembolans were absent from the stomachs of adults. Soft-bodied prey (crickets and spiders) are digested in 60 - 72 hr following ingestion at 25°C, whereas it takes 96 hr for the digestion of more heavily chitinized insects. THE oak toad, Bufo quercicus (Holbrook), occurs throughout the southeastern United States and prefers cypress bogs and upland habitats including xeric hammocks and sand pine scrub (Ashton and Ashton, 988). However, little detailed information is available on the ecology of this species. Previous studies include general observations on food habits (Crosby and Bishop, 1925 ; Duellman and Schwartz, 1958), habitat selection (Hamilton, 1955 ; Dalrymple, 1990), breeding season (Duellman and Schwartz, 1958) and development (Hamilton, 1955 ; Lee, 1986). In view of the paucity of information regarding the feeding preferences of this species coupled with the fact that little is known about the status of oak toad populations in Florida, the present study was conducted in order to gain more detailed information on the feeding ecology of B. quercicus froma hardwood forest (hammock) habitat. Hammocks occur throughout Florida and have been significantly impacted by human encroachment (Platt and Schwartz, 1990). I investigated the following parameters: (1) seasonal diets as reflected by stomach content analysis; and (2) the time required for digestion of various prey items. MATERIALS AND METHODs—Animals were collected between April and October, 1992. The study area was located along the Aucilla River, 6.5 km east of Dills, Florida (Madison County). A detailed description of the geology and vegetation of this hammock is given by Platt and Schwartz (1990). Hammock forests are characterized by an array of understory and overstory species of trees with scattered herbaceous vegetation. The dominant overstory trees in the study area include Quercus falcata, Q. hemispaerica, Pinus glabra, P. taeda, and Carya tomentosa while dominant understory vegetation includes Cornus florida, Ostrya virginiana, Aralia spinosa, Acer rubrum and Carpinus caroliniana. A randomized block design (Krebs. 1989) was used to identify twenty 10 x 10 m quadrats. Toads were collected at drift fences and pitfall traps (Punzo, 1974, 1992) and on foot at night using head lamps (Punzo, 1990). Drift fences were constructed with 50 cm high aluminum flashing. Within each quadrat, drift fences were placed along parallel sides with pitfall traps (50 liter plastic buckets) on opposite sides of the fence at 2 - m intervals. Traps were placed in the ground with the lip of the bucket flush with the ground surface. Time, place of capture, snout - vent length (SVL), and sex were recorded for each animal. Sex determination was based on the presence of secondary sex, characteristics associated with the male No. 1 1995] PUNZO- AN ANALYSIS OF FEEDING IN THE OAK TOAD 17 such as nuptial excrescence’s and darker throat coloration patterns. Pitfall traps were checked at two - hr intervals throughout the day. Stomach contents were obtained from anaesthetized toads within 5 - 8 hr after capture utilizing the stomach - flushing technique described in detail by Legler and Sullivan (1979). Data from stomach contents were recorded for adults (SVL : 24 - 33 mm) and juveniles (SVL: 11 - 14 mm) (Table 1). Since itis known that many Florida insects exhibit distinct seasonal activity patterns that peak before or shortly after the latter part of June (Deyrup, 1990), prey items were listed separately for spring (April 2 - June 20) and summer (June 21 - Sept. 15) months. Toads were held by hand and their mouths were gently opened with a plastic probe. Plastic coupling rings (6 - 10 mm diameter) kept the mouth opened at a maximum gape during the procedure. A Teflon intravenous catheter (Abbott Laboratories, Chicago, Illinois) was attached to a disposable plastic syringe (1 - 10 em’) equipped with a compression spring mechanism which automatically refills the syringe to 70% capacity after the plunger is depressed. With the mouth opened, the flushing canula was passed through the ring into the esophagus and stomach where it eventually rested against the pyloric region. Once in place, water from the syringe was gently pumped into the stomach with sufficient force to flush out the food material. The emergent food bolus was quickly removed with forceps to prevent any obstruction of the pharyngeal region. The stomach contents for each toad were placed in individual glass vials containing 80% ethanol for later identification. Prey items were identified to Order or Family depending on the degree of digestion. The information obtained for stomach contents in this study represents data from different individuals (no recaptures). The length (a) and width (b) of each prey item was measured to the nearest 0.01 mm (excluding legs and antennae) and the volume was determined according to the volume (V) of a prolate spheroid (Dunham, 1983) : V = 4/3 (a/2) (b/2)?. Levins’ measure of standardized niche breadth (BA) was calculated from data based on the size category of prey (percent volume) as described by Krebs (1989). Values can range from 0 (prey species in only one resource category) to 1.0 (prey species represented equally in all resource categories). Digestion rates were determined for captive adult female toads according to the method of Corse and Metter (1980). Ninety toads were divided equally into three experimental groups (N = 30 per prey group); each group was fed on one of three different prey species: adult cricket (C), Acheta domestica (body weight: 0.5 + 0.02 g); wolf spider (S), Lycosa lenta (0.3 + 0.04 g); grasshopper (G), Schistocerca americana (2.1 + 0.31 g). All prey species occur at the sites where B. quercicus was collected. Toads were placed individually in 3 - liter aquaria provided with moist paper towels as a substrate. All digestion experiments were conducted at 25° + 1°C in a Percival Model 80 environmental chamber (Boone, Iowa). This temperature was chosen based on body temperatures exhibited by toads when collected in the field. Toads were deprived of food for five days prior to testing in order to ensure clearing of the gut. Each toad was allowed to feed on the appropriate prey item (one prey item per toad). Toads were randomly sacrificed at specific intervals (12, 24, 36, 48, 60, 72, 84 or 96 hr) and their stomach contents removed and weighed to the nearest 0.01 g (wet weight) on a Mettler electronic analytical balance. These weights were compared to the weight of the prey item before ingestion and expressed as percent digestion (Corse and Metter, 1980). RESULTS AND DiIscussIoN—The prey items found in the stomachs of B. quercicus adults and juveniles are listed (Table 1). There was no significant difference between the diets of adult males and females (ANOVA, F = 1.7, p > 0.52). The most abundant prey taken by adults as indicated by percent frequency of occurrence included ants (69.8 - 84.0 %), spiders (54.2 - 56.1 %), carabid beetles (24.6 - 36.1 %), and termites (24.6 - 26.5 %), depending on the season. Mites and collembolans were not found in any of the adult stomachs. However, these taxa were well represented in the diet of juvenile toads : collembolans (87.3 - 91.3 %); mites (22.2 - 25.3 %). This suggests that adults ignore prey items that are below a certain minimum size. I have found similar results in the diets of the spadefoot toads (Scaphiopus couchi, S. holbrooki, and Spea multiplicata (Punzo, 1991, 1992) , the southern toad Bufo terrestris (Punzo, 1992) as well as the teiid lizard Cnemidophorus sexlineatus (Punzo, 1990). Juvenile toads also feed extensively on spiders (44.3 - 49.3 %), ants (87.3 - 92.5 %), and termites (76.5 - 80.9 %). Although the results indicate that a wide variety of prey are taken by both juveniles and adults, Levins’ measure of standardized niche breadth 18 FLORIDA SCIENTIST [VOL58 TABLE 1.— Stomach content analysis for Bufo quercicus. Data represent different individuals (no recaptures). The results are expressed as number of prey (N), frequency (F, percent of toad stomachs containing a particular prey item), and percent volume (V). There were no significant differences in dietary composition between sexes. Adults (SVL : 24 - 33 mm) Juveniles (SVL: 11 - 14 mm) Spring’ (N=94) Summer(N=73) Spring (N=81) Summer (N = 63) Prey taxon* N EF V N F V N EF We N eee. Annelida I, WAST 6 3 A RSS Rt foe aD) 24 14 £490 OO Acarina 0 0 0 0 0 O¢ Sle 2 258 rAomels 2209 Araneae pe GL OB 56.1 12.1 (47 _ “493 Ss hONiee Ss 44.3 9.4 Insecta Coleopter Carabidae (A) 39 SOM LO sea 24.6 117 0 0 0 3 et Ord Scarabaeidae (A) 7 TAP 22 4 OA So e@ 0 0 0 Ret 10 Tenebrionidae (A) 4 4.2, 10:3 0 0 0 0 0 0 0 OnE 20 Unidentified (A) 36 SUAS Sis) Pi 30:1. 12.3...16 17.2) 4.8) ig ee Sees.4 Collembola (A) 0 0 0 0 0 0 94 — 91.3, I4.3) oO ee Sies shil=7 b) Diptera (A) Tl DO 0.3 4] 0.2 14 JAS es fe) ie 9 Heteroptera(A,N) 9 te! iD 4 5.4 ali 0 0) 0 0 0 0 Hymenoptera Formicidae (A)101 840 134 81 69:8) 11:3 117 925) Uae SPs 17.5 Isoptera (A) 38 26:9) 16.30 y24 246 4.2 74, 16:5, 68am 80.9 13.7 Lepidoptera (A) 9 9.5 or LSGr US 0 0 = 6.3 0.3 (QL) Se, 2a: 6 82.19 21 2098 Grain, DOs 1.0 Orthoptera Acrididae (A, N) 9 9.5 2.4 4 SA RF Eb 6:lin: KOR eS 4.7 0.5 Romalidae (A, N) 0 0 0 S) Sie Oe 0 0 0 2 Sor OSD Tettigoniidae (A) 5 3.3 0.5 3 All ee O aan 8.6) a 0 0 Unidentified(A,N) 14. 12.7 5.6 9 IDS ody 163 oT | GiGi Aas TA ies et Unidentified arthropod fragments 71 63:55 B20 ea 7, 03.4 26.9 31 33.3 18:3 42 49.2 26.9 Plant material 24 25.0 14 19:1 ae, 20.9 27 42.8 A Prey categories : A (adult) ,“N (nymph) , L (larva) B Spring (April 2 - June 20); Summer (June 21 - Sept. 15) No. 1 1995] PUNZO—AN ANALYSIS OF FEEDING IN THE OAK TOAD 19 TABLE 2.—The relationship between amount of time after feeding and percent digestion in Bufo quercicus (SVL : 25 - 32 mm ) for several prey species: C = adult cricket, Acheta domestica; S = wolf spider, Lycosa lenta; G = adult grasshopper, Schistocerca americana. Prey weights (g) are means + S.D. Percent digested ( % ) Time after digestion ©; S G (hr ) (0.5 + 0.02 g) (0.3 + 0.04 g) (2.1+ 0.5 ¢) 12 16.3 DNAS) 13.5 24 24.7 33.8 AD. 7 36 SUD 70.2 Sle 48 61.3 82.5 45.3 60 86.4 96.1 61.4 Tp Oiell 72.6 84 84.3 96 94.5 yielded the following values : adults (BA = 0.4784 for summer months; 0. 4258, spring); juveniles (0.3864 and 0.3672, respectively). These values reflect the fact that several prey species are eaten in much higher numbers than others (Table 1). Arthropods with well-known chemical defenses and aggressive behavior such as blister beetles (Meloidae) and velvet ants (Mutillidae), commonly found in the study area (personal observation), were not found in any of the stomachs. Digestion rates for various prey species are shown in Table 2. A Kruskal - Wallis test (Sokal and Rohlf, 1981) showed a significant difference in the rate of digestion between the more heavily chitinized grasshopper and the softer-bodied crickets (H = 11.2, p < 0.01) and spiders (H = 16.3 , p < 0.01). This may explain why acridid grasshoppers are found in low numbers in the diets of juveniles and adults (Table 1). Toft (1985) suggested that the prey of many anurans can be divided into two main categories: (1) ants and other slow-moving, chitinous arthropods, and (2) all other types. Ants have been shown to constitute a significant proportion of the diet in bufonids, dendrobatids and other anurans (Toft, 1980 ; Duellman and Trueb, 1986) and were found to be an important component of the diet of B. quercicus in this study ( 69.8 - 92.5 % of the stomachs contained ants ). However, the overall diet of B. quercicus is more varied than those reported for many tropical anurans (Toft, 1985). The diet of B. quercicus is similar to that reported for B. terrestris and S. 20 FLORIDA SCIENTIST [VOL 58 holbrooki from another area of Florida (Punzo, 1992). Since both of these species can be sympatric and/or syntopic with B. quercicus, future studies should assess the degree (if any) of competition and resource partitioning between these and other anurans . ACKNOWLEDGMENTS—1 would like to thank T. Punzo and A. Kirk for assistance in the field, and B. Garman, Dept. of Mathematics, for consultation on statistical analyses, and anonymous reviewers for comments on an earlier draft of the manuscript. A Faculty Development Grant from the University of Tampa made much of this work possible. LITERATURE CITED AsHToN, R.E. JR. anpD P.S. Asuton. 1988. Handbook of amphibians and reptiles of Florida. Part III. Amphibians. Windward Publs., Inc., Miami, Florida. Corse, W.A. AND D.E. METTER. 1980. Eeonornes adult feeding and larval growth of Rana catesbeiana on a fish hatchery. J. Herpetol. 14 : 231 - 238. Crospy, C.R. AND S.C. BisHop. 1925. A new genus and two new species of spiders collected by Bufo quercicus (Holbrook). Fla. Entomol. 9 : 33 - 36. DatryMPLeE, G.H. 1990. Habitat suitability index model : oak toad. In W. Richter and E. Myers, (eds.). Suitability index models used for the Bird Drive Everglades Basin Special Area Management Plan. Fla. Dept. Envir. Res. Management, Dade Co., Tech. Report 90 - 1. Deyrup, M. 1990. Footprints on the sands of time. Fla. Entomol. 34: 1 - 11. DUELLMAN, W.E. AND A. SHwarz. 1958. Amphibians and reptiles of southern Florida. Bull. Fla. State Mus. 3: 18] - 324. AND L. TRUEB. 1986. Biology of amphibians. McGraw - Hill, N.Y., 670 pp. Dunnam, A.E. 1983. Realized niche overlap, resource abundance and intensity of inter specific competition. In R.B. Huey, E.R. Pianka, and T.W. Schoener (eds.), Lizard Ecology, pp. 261 - 280, Harvard University Press, Cambridge, MA. HaMILTON W.]. 1955. Notes on the ecology of the oak toad in Florida. Herpetologica 11 : 205 - 210 Kress, C.J. 1989. Ecological Methodology. Harper and Row Publ., New York, N.Y. , 654 pp LEE J.C. 1986. Is the large male mating advantage in anurans an epiphenomenon ? Oecologia 69 : 207 = YI LEGLER, J.M. AND L.J. SuLtivan. 1979. The application of stomach flushing to lizards and anurans. J. Herpetol. 35 : 107 - 110. Piatt, W.]., M.W. Scuwartz, R. L. Myers AND J. Ewer Myers,. 1990. Temperate hardwood forests. pp. 194 - 229 In: (eds.), Ecosystems of Florida, Univ. of Central Florida Press, Orlando, Florida. Punzo, F. 1974. An analysis of the stomach contents of the gecko, Coleonyx brevis. Copeia 1974 : 779 - 780. . 1990. Feeding ecology of the six-lined racerunner (Cnemidophorus sexlineatus) in southern Florida. - Herp. Rev. 21 : 33 - 35. . 1991. Feeding ecology of spadefooted toads (Scaphiopus couchi and Spea multiplicata) in western Texas. Herp. Rev. 22 : 79 - 81. . 1992. Dietary overlap and activity patterns in sympatric populations of Scaphiopus holbrooki (Pelobatidae) and Bufo terrestris (Bufonidae). Fla. Scientist 55 : 38 - 44. SoKAL, R.R. AND F.J. RonF. 1981. Biometry (2nd ed.) W.H. Freeman and Co., N.Y., 859 pp. Torr, C.A. 1980. Feeding ecology of thirteen syntopic species of anurans in a seasonal tropical environment. Oecologia 45 : 131 - 141., 1985. Resource partitioning in amphibians and reptiles. Copeia 1985 : 1 - 21. Florida Scientist 58(1): 16-20. 1995. Accepted: August 27, 1994. No. 1 1995] 2] Biological Sciences CULTURABLE AIRBORNE FUNGI IDENTIFIED FROM HEATING, VENTILATION AIR CONDITIONING UNITS (HVAC) FROM HOME ENVIRONMENTS WITHIN THE SOUTHEASTERN FLORIDA REGION K.A. KuEHN”, ROBERT GARRISON?) AND LARRY ROBERTSON”) Department of Biological Sciences", University of Alabama, Tuscaloosa, AL 35487, Mycotech Biological Inc”., Route 1 Box 182, Jewett, TX 75846. Apstract: Circulating indoor air of 730 residential homes within the southeastern Florida region was examined over a three year period (1980-1992) for the presence of culturable airborne fungal propagules. Investigations involved the exposure of 2.5% malt extract agar to ventilation air streams emanating from HVAC (heating-air conditioning-ventilation) units. Cladosporium spp. (72%), Penicillium spp. (45%), and yeast spp. (38%) were the most common taxa identified during this study period. Some 54% of the homes investigated had fungal isolates that remained unidentifiable (sterile hyphae), and 8% of the homes sampled were negative for fungi. MicrosiAL contamination of indoor air has recently gained considerable attention as a possible cause of indoor air related illness or symptoms within home or work environment (Tobinetal., 1987; Moreyetal., 1990; Miller, 1992). Energy conservation measures introduced during the early 1970s in the United States and other countries have resulted in the construction of numerous “energy efficient” homes and commercial buildings, which are effectively isolated from the outdoor environment. Subsequently, many indoor habitats have severely reduced rates of fresh air exchange, which can result in the accumulation and proliferation of microorganisms (bacteria, fungi) and associated metabolites (endotoxins, mycotoxins) within circulating indoor air. Several investigators have sought to characterize airborne microbial communities of indoor air from both commercial and domestic environments (Gravesen, 1978; Hunter et al., 1988; Miller et al., 1988; Tarlo et al., 1988; Kuehn et al., 1992; Garrison et al. 1993). Since many individuals spend a majority of their existence indoors, the examination of the fungal community associated with indoor air may provide information on the population dynamics of indoor fungal contaminants from differing geographic localities, and thus contribute to our understanding of possible causative agents involved in hypersensitive reactions. This study was conducted to identify the prevalent culturable airborne fungal propagules from indoor air of residential environments within the southeastern Florida region using a forced air ventilation exposure technique. Metuops—730 homes were examined for the presence of airborne fungi over a three year period(1990-1992). Isolation of fungal propagules involved the exposure of culture plates containing 2.5% malt extract agar. A single plate exposure methodology was used, with the exception of only a few homes in which additional plates were utilized. A total 771 culture plates were examined. Culture plates were heat sealed to ensure sterility prior to transport to testing areas. 29 FLORIDA SCIENTIST [VOL 58 Culture plates were exposed to ventilation air streams emitting from HVAC (heating, ventilation and air conditioning) units within each home as described in Garrison and co-workers, (1993). HVAC units were turned off prior to sampling exposures. Access panels to units were removed, along with associated filters, to allow visual inspection of evaporative coils and plenum areas for fungal growth. Evaporative coils, plenum, and associated filters were tapped to dislodge any attached material prior to refitting of the access panels. The culture plate(s) were removed from sealed packaging and positioned at a 90° angle to emitting air flow. Units were manually turned on and operated continuously for 10 min, after which culture plates were removed and resealed for transport. Cultures were returned to the laboratory and incubated at ambient temperatures (22-25°C) and (12h:12h) normal light:dark cycles. Cultures were examined 5-7 days after exposure and sporulating fungi identified by standard microscopic techniques. Further examination of cultures was conducted over a 5-wk period for identification of slower sporulating species. Deuteromycotina Hyphomycetes Zygomycotina 0 10 20 30 40 50 60 70 80 90 100 0 10 20 30 40 50 60 70 80 90 100 Cladosporium Rhizopus Sterile hyphae Penicillium Unidentified Yeasts Mucor Unidentified (Mucorales) 0.5% < Aspergillus ce Drechslera Mycotypha Rowe eee-e Alternaria Epicoccum Ascomycotina 0 10 20 30 40 50 60 70 80 90 100 Aureobasidium Curvularia Geotrichum Chaetomium Acremonium Myxotrichum Candida Sordaria Rhodotorula Trichoderma Monocillium Basidiomycotina Gras 0 10 20 30 40 50 60 70 80 90 100 Fusarium Isaria 1.0% < Sporobolomyces Scopulariopsis Pithomyces Stemphylium Negative : 0 10 20 30 40 50 60 70 80 90 100 Botyrtis ‘ Verticillium v Negative for fungi Ceolomycetes 0 10 i) 30 40 50 60 70 80 90 100 re ee on Or | Phoma Fic. 1. Percentage frequency of fungal taxa indentified from exposed culture plates. No. l 1995] KUEHN ET.AL.—CULTURABLE AIRBORNE FUNGI 93 RESULTs AND Discussion—The composition of fungi identified from exposed cultures encompassed the Deuteromycotina, Zygomycotina, Ascomycotina and Basidiomycotina (Fig. 1). The predominant fungi identified during this study comprise common fungal taxa, particularly hyphomycetes. The dominance of such fungal taxa, particularly Cladosporium and Penicillium is not uncommon as com- pared to other indoor studies (Gravesen, 1978; Hunter et al., 1988; Miller et al.,1988; Kuehn et al., 1992). Deuteromycete genera include well known soil and plant inhabiting species,and are often the most common mycoflora in aerobiological samples (Gregory, 1973). Penicillium species, in particular, is often one of the prevalent fungal organisms encountered from indoor air (Miller, 1992). The more frequent isolation of Penicillium species from exposed cultures is of interest in that “smaller” conidial species are less likely to be recovered by simple gravity plate exposure versus volumetric sampling (Burge and Solomon, 1987). The frequent isolation of Penicillium spp. from exposed culture plates in this study may indicate that conidial spores occur in airborne concentrations great enough to be successfully recovered within the homes investigated, or that the forced air ventila- tion techniques utilized in this study provide more favorable conditions for collection by maximizing entrapment of airborne fungal propagules on agar surfaces. The high percentage of unidentifiable (or sterile) fungal colonies obtained in this and other studies (Gravesen, 1978; Kuehn et al., 1992) represents a tremendous problem in identifying potential fungal allergens. Such isolates expressed no distin- guishing morphological structures under the culture conditions employed, and thus remain unidentifiable. Although the media utilized in this study is the accepted medium for fungal isolation and characterization (ACGIH, 1989), it is likely that such media lacks specific nutrient requirements for growth and or sporulation in these fungal isolates (e.g 54% of the isolates remained sterile). Additionally, these isolates may well represent potential indoor allergens. The condition of the indoor environment in terms of temperature, humidity (moisture) and utilizable substrates will determine the occurrence of fungi within the home and the severity of proliferation. The examination of indoor fungal propagules may provide useful information in determining the predominant fungi of certain geographic regions. In addition, such investigations may increase the scope of potential causal factors regarding hypersensitive reactions expressed among individuals within home environments, as patients can often be skin tested using antigens of fungi isolated from their homes (Tarlo et al, 1988). Culture plate analysis of indoor air and associated HVAC systems may therefore yield some useful information regarding indoor fungal bioaerosols. ACKNOWLEDGMENTS—The authors wish to acknowledge Deane Ellis and technical associates of Climate Control Services, Del Ray Beach, Florida for their support and participation in this investigation. 24 FLORIDA SCIENTIST [VOL 58 LITERATURE CITED AMERICAN CONFERENCE OF GOVERNMENTAL INDUSTRIAL HYGIENISTS (ACGIH). 1989. Guidelines for the assessment of bioaerosols in the indoor environment. American Conference of Governmental Industrial Hygienists, Cincinnati, Oh. BurcE, H.P. anpD W.R. SoLtomon. 1987. Sampling and analysis of biological aerosols. Atmos. Environ. 21:451-456. GarrISON, R.A., L.D. ROBERTSON, R.D. KOEHN AND S.R. Wynn. 1993. Effect of heating-ventilation-air conditioning system sanitation on airborne fungal populations in residential environments. Ann. Allergy 71(6):548-556. Grecory, P.H. 1973. The Microbiology of the Atmosphere, 2nd ed. Leonard Hill Books, Aylesbury, England. 377p. GravEsoNn, S. 1978. Identification and prevalence of culturable mesophilic microfungi in house dust from 100 Danish homes. Allergy 33:268-272. Hopcson, M.J. anD P.R. Morey. 1989. Allergic and infectious agents in the indoor air. W.R. Sevan (ed). Immunology and Allergy Clinics of North America, Vol.9, Airborne Allergens. (p. 399-412). W.B. Saunders, Philadelphia. PA. Hunter, C.A., C. Grant, B. FLANNIGAN AND A.F. Bravery. 1988. Mould in building: spora of domestic dwellings. Int. J. Biodeterior. 24:81-101. KuEHN, K.A., R. Garrison, L. RoBERTSON, R.D. KoEun, A.L. JOHNSON AND W.J. REa. 1992. isn Aeaten of AbOUe microfungal populations from home environments within the Dallas-Fort Worth (Texas) region. Indoor Environ. 1:285-292. MILLER, J.D., A.M. LaFLAMME, Y. Sopot, P. LAFONTAINE AND R. GREENHALGH. 1988. Fungi and fungal products in some Canadian houses. Int. J. Biodeterior. 24:115-123. 1992. Fungi as contaminants in indoor air. Atmos. Environ. 26:2163-2172. . 1992. Fungi as contaminants in indoor air. Atmos. Environ. 26:2163-2172. Morey, P.R., FREELY, J.C. SR. AND J.A. OTTEN (eds). 1990. Biological contaminants in indoor environ- ments. American Society of Testing and Materials STP 1071. 243 p. Philadelphia PA. Taro, S.M., A. FRADKIN AND R.S. Tosin. 1988. Skin testing with fungal extracts of fungal species derived from the homes of allergy clinic patients in Toronto, Canada. Clin. Allergy 18:45-52. Tosin, R.S., E. BARANOwsKI, A.P. GILMAN, T. Kurper-Goopman, J.D. MILLER AND M. Gippincs. 1987. Significance of fungi in indoor air: report of a working group. Can. J. Pub. Health 78(Special insert):Si-S 14. Florida Scient. 58(1): 21-24. 1995. Accepted: August 2, 1994. No. 1 1995] 25 Biological Sciences POSTPARTUM REGRESSION OF CORPORA ALBICANTIA IN WHITE-TAILED DEER RONALD F. LABISKY AND ANDREAS R. RICHTER! Department of Wildlife and Range Sciences, University of Florida, Gainesville, Florida 32611-0430 Asstract— Paired ovaries, collected from 51, 21'” year-old white-tailed deer (Odocoileus virginianus) in the upper Everglades system of south Florida during 1978-80, were examined by serial histology; the sample represented =2 paired ovaries from each calendar month, except December. Breeding occurred between 21 July and 11 October (mean = 10 August); parturition occurred between 1 February and 29 April (mean = 26 February). A corpus albicans of pregnancy was identified in 52 ovaries from 38 deer. The maximum diameter of corpora albicantia of pregnancy was approximately 4mm among females <1- month postpartum, but had regressed to <2mm by the onset of the breeding season in late July (5 months postpartum) and to <1 mm by the onset of the hunting season in mid-November (9 months postpartum). Corpora albicantia of pregnancy <1 mm diameter were inseparable from both corpora albicantia of pregnancy of the previous year and corpora lutea of estrus. Use of corpora albicantia of pregnancy to estimate productivity of white-tailed deer in subtropical Florida is restricted to a postpartum period of approximately 4 months, which (1) precludes the option for obtaining 2 years of productivity data from the paired ovaries of a given deer, and (2) limits the assessment of productivity to be derived from ovaries of hunter-collected females in autumn to those animals harvested within 4 months of parturition Probuctivity data provide important information for the management for deer populations. Fetal counts can be used to obtain productivity data from pregnant females, whereas other techniques must be used to determine productivity from females that are not pregnant. Cheatum (1949), who examined ovaries of pregnant white-tailed deer macroscopically, reported being able to distinguish between the corpus luteum of pregnancy from the breeding season of collection and the corpus albicans of pregnancy from the preceding breeding season, thereby facilitating the obtainment of productivity data for 2 breeding seasons from the ovaries of a single pregnant female. Similarly, Brokx (1972) reported that scars of the penultimate pregnancy in the Venezuelan white-tailed deer (O. v. gymnotis) remained recogniz- able for 8-18 months. However, productivity data similarly derived from the macroscopic interpretation of ovaries from black-tailed deer (O. hemionus) (Golley,1957), andthe conspecific red deer (Douglas, 1966) and North American elk (Cervus elaphus) (Morrison, 1960) often were invalid. In addition to true corpora lutea, accessory corpora lutea, i.e., unovulated luteinized follicles and other lutein- ized structures, have been identified in white-tailed deer (Mansell, 1971: Brokx, 1972), and red deer (Douglas, 1966) / North American elk (Halazon and Buechner, 1956). Size criteria have been used to separate accessory corpora lutea and other luteinized structures from true corpora lutea/albicantia of pregnancy in white-tailed Present address': Smith Lane R.R. 1, Box 234B, Canajoharie, NY 13317. 26 FLORIDA SCIENTIST [VOL 58 deer (Teer et al., 1965; Trauger and Haugen, 1965). Gibson (1957) reported histologic procedures for differentiating between the corpus albicans resulting from the corpus luteum of estrus and from the corpus luteum of pregnancy in white-tailed deer. The first ovulation of each breeding season in white-tailed deer (Harder and Moorhead, 1980) and black-tailed deer (Thomas and Cowan, 1975) appears to be associated with a “silent” estrus, i.e., no estrous behavior is exhibited by the female. The next ovulation occurs about 14 days later, which reflects an interovulatory interval of about half that of a normal estrous cycle. Females first express estrous behavior in conjunction with the second ovulation of the season. Although the corpus luteum from the silent estrus regresses quickly in size (Thomas and Cowan, 1975), the regression rate of the corpus luteum of pregnancy is poorly documented (Richter, 1981). Determination of the rate at which the corpus albicans of pregnancy regresses would document the length of time within which the structures are macroscopically identifiable, and, thereby, useful for estimating productivity of non- pregnant, postpartum does. Accordingly, the objective of this study was to determine histologically the postpartum rate of regression of the corpus albicans of pregnancy in white-tailed deer. Stupy AREA—Rotenberger Wildlife Management Area (WMA), an 11,400-ha tract in south Florida (26° 30' N; 81° 05' W), was a part of the Everglades ecosystem prior to drainage for agriculture, which began in the late 1890s. Although water levels in this region of low relief are now controlled by canals and structures, there is still a marked wet regime in summer and a dry regime in winter. Most of the annual rainfall (mean: 134 cm) occurs during summer; in autumn, the region begins to dry as the water drains slowly southward. The southern portion of the study tract is still primarily a sawgrass (Cladium jamaicensis )/hardwood tree island community, but the northern portion, which is now drier than during predrainage years, has been invaded by secondary successional vegetation—herbs and shrubs. Estimated deer density on the Rotenberger WMA was approximately 7 deer/km’ in the late 1970s (Breault, 1981). The study site was subjected to a 2-month hunting season, beginning in mid-November annually; hunting was restricted principally to males-only, although limited antlerless hunts were permitted. MeETHops—Fifty-one paired ovaries from 11/,- to 4'/, - year-old deer were collected from Rotenberger WMA between 1978 and 1980, and examined histologically. The sample consisted of >2 paired ovaries for each calendar-year month except December; the monthly samples, generally collected on the same day of the month, were spaced at 30-day intervals. Deer age was determined by tooth replacement and wear (Severinghaus, 1949). Ovaries were fixed in formalin, embedded in. paraffin blocks and sectioned at a thickness of 10 microns. Every 10th section was mounted and stained with Masson’s Trichrome (Luna, 1968). Breeding at Rotenberger WMA, estimated by ageing fetuses (Short, 1970), occurred between 21 July and 11 October (median = 8 August; mean = 10 August, SD = 16 days; n = 48) (Richter, 1981; Richter and Labisky, 1985); fawning, using a 200-day gestation period (Cheatum and Morton, 1946; Haugen and Davenport, 1950; Haugen, 1959), subsequently occurred between 1 February and 29 April (mean = 26 February). Corroboratively, Boulay (1992) reported a median fawning date of 22 February for a nearby study site in the Big Cypress National Preserve/Everglades National Park (25° 40' N., 81°15' W.). Microscopic histologic examination involved the ovarian corpora complex. The maximum diam- eter of ovarian structures was measured with an ocular micrometer under appropriate magnification (10x, 20x, 40x or 100x). No distinction was made between atretic and developing follicles. A corpus No. 1 1995] LABISKY AND RICHTER—POSTPARTUM REGRESSION IN WHITE-TAILED DEER 97 luteum of the estrous cycle (CLE), which regresses prior to a subsequent ovulation in the absence of conception, becomes a corpus albicans of the estrous cycle (CAE). If conception and implantation occur, the CLE persists as the corpus luteum of pregnancy (CLP), which regresses after parturition and is then termeda corpus albicans of pregnancy (CAP). Corpora albicantia were differentiated from corpora lutea by their staining properties. Although both structures have a luteal cell matrix that stains red with Masson’s Trichrome, corpora albicantia are surrounded by and infiltrated with connective tissue that stains blue with Masson’s Trichome. CAE and CAP were distinguishable because CAE lack the numerous thick-walled blood vessels that characterize CAP (Gibson, 1957). Luteinized ovarian struc- tures were more difficult to differentiate. Technically, true corpora lutea are formed through the luteinization of follicles that have released an ovum during ovulation; secondary corpora lutea are formed from follicles that ovulate and luteinize during pregnancy; and accessory corpora lutea are unovulated, luteinized follicles with an entrapped ovum (Haneeon and Weir, 1977). Some ovaries from pregnant deer contained small corpora lutea-type structures in excess of the number of fetuses; these structures, in the absence of a retained ovum, were called “luteal bodies”. Data were analyzed using Statistical Analysis System (SAS) procedures. Mean diameters of ovarian structures were expressed as the mean of the maximal sectioned length and width, and used as the dependent variable in the linear regression analysis (Steel and Torrie, 1980). REsuLTs—An average of approximately 70 histological sections from each of the paired ovaries from 51 females, 1'/, to 4'/, years in age, was examined and inter- preted. Forty-five of the 51 females (88%) showed overt signs of reproductive activity, i.e., lactation (n = 24), pregnancy (n = 14), or substantial asymmetry of the uterine horns (n = 7), and contained structurally distinct corpora lutea or corpora albicantia in their ovaries. The 6 females that exhibited no overt signs of reproductive activity were younger does, either 1'/,- or 2'/, -years old. However, histological examination of the ovaries revealed that 4 of the 6 females actually were reproduc- tively active—2 exhibited corpora lutea (attributable to coincident rut) and 2 exhibited CAE (1 of these, a 1'/,-year-old, had 6 CAE); the remaining 2 females exhibited only follicles. Thus, 49 (96%) of the 51 deer in the sample exhibited reproductive activity, which was similar to the 92% pregnancy rate reported for females >1 year of age in Florida (Richter, 1981). Fifty-two CAP were found in the ovaries of 38 of the 49 reproductively active females. CAP were largest, about 4 mm in diameter, immediately after the mean date of parturition. CAP regressed progressively thereafter, declining to measured diameters of about 2 and 1 mm at 4 and 9 months postpartum, respectively (Fig. 1). Fight of the 13 females that did not possess CAP, but were pregnant, were collected >8 months post-fawning (October-February); in these females, CAP from previous pregnancies had regressed to such an extent that they were no longer distinguishable from the ovarian stroma. Three of the 13 females (2- to 3-years old) that did not possess CAP were collected in May and June, a time when CAP should have been >1-mm in diameter; it is probable that these 3 females may not have bred the previous season. Similarly, 1 female collected in August and 1 in September did not exhibit CAP in their ovaries; these females either were barren the previous season or their CAP had already regressed to an indistinguishable size. Discussion—This histological analysis of ovarian structures measured the postpartum longevity of CAP to access the validity of using CAP counts for determining past productivity of white-tailed deer. Cheatum (1949) reported that FLORIDA SCIENTIST [VOL 58 9.0 Y = 3.81 - 038X ‘ : R? = 0.67 » 40 oe 5 P <0.001 Se ° = 52 eg ene --- 95%C.L. MEAN DIAMETER OF CAP (mm) » 0 1: 2 8 4 5:6 qo MONTHS POSTPARTUM Fic. 1. Postpartum regression of 52 corpora albicantia of pregnancy (CAP) from the ovaries of 38 female white-tailed deer, 1'/, to 4'/, years in age, Rotenberger Wildlife Management Area, Florida. The number of months postpartum is based on the mean date of fawning (26 February) for the Rotenberger population (Richter and Labisky, 1985). CAP , but not CAE, were pigmented; in contrast, Brolkx (1972) reported that both structures were pigmented. Golley (1957), citing evidence from the ovaries of an 18 year-old black-tailed deer that presumably had never been bred, reported that other ovarian corpora-structures, in addition to CAP, exhibited pigmentation. Therefore, the presence of or absence of pigmentation appears to be a questionable procedure for differentiating between CAP and CAE macroscopically. Productivity determined from counts of pigmented ovarian structures was 18% and 19% greater in black-tailed deer (Golley, 1957) and white-tailed deer (Teer et al., 1965), respectively, than that determined from fetal counts. Elevated CAP counts could result from the death and subsequent resorption of 1 fetus from a litter of 2 fetuses. Although rates of embryonic resorption in white-tailed deer are poorly documented, the frequency of dead fetuses in twin and triplet litters in New York herds was found to be low, 2% and 5%, respectively (Hesselton and Jackson, 1971). Depressed CAP counts could be a product of polyovulation and/or identical twins, i.e., 1 follicle would produce 2 ova (fetuses) but result in a single CAP. However, the frequency of polyovulation or identical twins among deer herds also is low, 0.05% in New York (Hesselton and Jackson, 1971) and 2.5% in Texas (Teer et al., 1965). No. 1 1995] LABISKY AND RICHTER—POSTPARTUM REGRESSION IN WHITE-TAILED DEER Ae) Nonetheless, the rate of productivity determined from histological counts of CAP in ovaries of the 38 females from Rotenberger WMA was 1.37 CAP per female, which was in relatively close agreement with the concurrently derived rate of 1.26 fetuses per pregnant female (Richter and Labisky, 1985). Numerous studies have reported the presence of more corpora lutea in ovaries than fetuses in the uteri of pregnant females (Hesselton et al., 1965; Teer et al., 1965; Trauger and Haugen, 1965; Hesselton and Jackson, 1974; Mansell, 1971; Haugen, 1975; Jacobson et al., 1980; Richter, 1981). These additional luteal structures, which are generally smaller than CLP, also will form corpora albicantia during the postpartum period. The postpartum regression rate of these additional corpora albicantia is not known, but is assumed to be similar to that of CAP. However, there is no known way of separating between these structures and CAP resulting from true CLP; thus, in this analysis they were all grouped as CAP. CAP decrease in size from about 4 mm in diameter at parturition to about 1 mm in diameter between 6 end 9 months postpartum, after which time they decrease only slightly before becoming indistinguishable (Gibson, 1957; Mansell, 1971; This Study). The variability in regression rates of CAP suggest that some may blend into the ovarian stroma sooner than others (Gibson, 1957; This Study). Also, CAE seem to regress more quickly in size than do CAP. CAE in the ovaries of 3 females, which were bred successfully during their second estrus period, had regressed to <2 mm in diameter after 2 months post-parturition; these CAE, very likely, were a product of the “silent” heat. At parturition, following a 200-day gestation period, CAE have regressed to <1 mm in diameter; in contrast, CAP are approximately 4 mm in diameter. Some of the smaller CAE persist throughout the postpartum period (Golley, 1957) before disappearing into the ovarian stroma; thus, the best way to distinguish CAP from CAE would be to count CAP before they have regressed to <1 mm in diameter. Thus, the appropriate time to count verifiable CAP is within the first 4 months after parturition, a time when CAP are >2 mm in diameter and can be readily separated from the smaller CAE and/or the smaller CAP that are older than 12 months (previous pregnancy). In summary, use of CAP to estimate productivity in white-tailed deer in subtropical Florida is restricted principally to a postpartum period of approximately 4 months, which (1) precludes the option for obtaining 2 years of productivity data from the paired ovaries of a given deer, and (2) limits the assessment of productivity derived from ovaries of hunter-killed females to those harvested within 4 months of fawning. ACKNOWLEDGMENTS—This study was supported by the Florida Game and Fresh Water Fish Commission; F. H. Smith, Jr., provided administrative assistance, and T. A. Breault, R. W. Ellis, V. J. Heller, T. W. Regan and J. D. West collected the sample of females. Histological facilities at University of Florida (UF) were provided by D. Caton and A. Watson. D. A. Labisky-McClung (UF), and D. J. Black and V. M. Shille (UF), assisted in the preparation and interpretation, respectively, of the histological sections. M. J. Fields and D. E. Fritzen (UF), and M. C. Conner (Remington Farms) 30 FLORIDA SCIENTIST [VOL 58 reviewed the manuscript. This paper is a contribution (Journal Series 8352) of the Florida Agricultural Experiment Station, Gainesville. LITERATURE CITED Bou ay, M. C. 1992. Mortality and recruitment of white-tailed deer fawns in the wet prairie/tree island habitat of the Everglades. M.S. Thesis, Univ. of Florida, Gainesville. 77 pp. BreEAULT, T. A. 1981. F fons Game and Fresh Water Fish Commission, Panama City, FL, Pers. Commun. Brokx, P. A. 1972. Ovarian composition and aspects of the reproductive physiology of V SOSELE Ia white- tailed deer (Odocoileus virginanus gymnotis). J. Mammal. 53: 760-773. CueatuM, E. L. 1949. The use of corpora lutea for determining ovulation incidence aad variations in the fertility of white-tailed deer. Cornell Vet. 39:282- 291. AND G. H. Morton. 1946. Breeding season of white-tailed deer in New York. J. Wildl. Manage. 10:249-263. Douc as, M. 7. W. 1966. Occurrence of accessory corpora lutea in red deer Cervus elaphus. J. Mammal. AT? las: Gipson, D. 1957. The ovary as an indicator of reproductive history in the white-tailed deer Odocoileus virginianus borealis, Miller. M.S. Thesis, Univ. Toronto, Toronto, Canada. 61 pp. Go -ey, F. B. 1957. An appraisal of ovarian analysis in determining reproductive performance of black- tailed deer. J. Wildl. Manage. 21:62-65. Ha.azon, G. C. anD H. K. BuEcHNER. 1956. Postconception ovulation in elk. Trans. North Am. Wildl. Conf. 21:545-554. Harber, J. D. AND D. L. Moorneab. 1980. Development of corpora lutea and plasma progesterone levels associated with the onset of the breeding season in white-tailed deer (Odocoileus virginianus). Biol. Reprod. 22:185-191. Harrison, R. J. AND B. J. Werr. 1977. Structure of the mammalian ovary. Pp.113-217. In: Zuckerman, L. and B. J. Weir (eds.) The Ovary. (2nd ed.) Volume 1: General Aspects. Academic Press, New York, NY. Haucen, A. O. 1959. Breeding records of captive white-tailed deer in Alabama. J. Mammal. 40:108-113. . 1975. Reproductive performance of white-tailed deer in Iowa. J. Mammal. 56:151-159. AND L. A. Davenport. 1950. Breeding records of white-tailed deer in the upper peninsula of Michigan. J. Wildl. Manage. 14:290-295. HESSELTON, W. T. AND L. Jackson. 1971. Some reproductive anomalies in female white-tailed deer from New York. N. Y. Fish and Game J. 18:42-51. AND L. W. Jackson. 1974. Reproductive rates of white-tailed deer in New York State. N. Y. Fish and Game J. 21:135-152. , C. W. SEVERINGHAUS AND J. E. Tanck. 1965. Population dynamics of deer at the Seneca Army Depot. N. Y. Fish and Game J. 12:17-30. Jacosson, H. A., D. C. Guynn, JR., R. N. GRIFFIN AND D. Lewis. 1980. Fecundity of white-tailed deer in Mississippi and periodicity of corpora lutea and lactation. Proc. Southeast. Assoc. Fish and Wildl. Agencies 30:30-35. Luna, L. G. (ed.). 1968. Manual of Histologic Staining Methods of the Armed Forces Institute of Pathology. (3rd ed.) McGraw-Hill Book Co., New York, NY., 258pp. MANSELL, W. D. 1971. Accessory corpora lutea in ovaries of white-tailed deer. J. Wildl. Manage. 35:369- 374. Morrison, J. A. 1960. Ovarian characteristics of elk of known breeding history. J. Wildl. Manage. 24:297- 307. RicuTER, A. R. 1981. Comparisons of reproductive characteristics in geographically disjunct white-tailed deer herds in Florida. M.S. Thesis, Univ. Florida, Gainesville. 81 pp. AND R. F. Lapisxky. 1985. Reproductive dynamics among disjunct white-tailed deer herds in Florida. J. Wildl. Manage. 49:964-971. SEVERINGHAUS, C. W. 1949. Tooth development and wear as a criteria of age in white-tailed deer. J. Wildl. Manage. 13:195-216. SHorT, C. 1970. Morphological development and aging of mule and white-tailed deer fetuses. J. Wildl. Manage. 34:383-388. STEEL, R. G. D. aND J. H. Torrie. 1980. Principles and Procedures of Statistics: A Biometrical Approach. (2nd ed.) McGraw-Hill Book Co., New York, NY., 633pp TEER, J. G., J. W. THomas anD E. A. WaLKER. 1965. Ecology and management of white-tailed deer in the No. 1 1995]LABISKY AND RICHTER—POSTPARTUM REGRESSION IN WHITE-TAILED DEER 3] Llano Basin of Texas. Wildl. Monogr. 15. 62pp. Tuomas, D.C. anpD I. McT. Cowan. 1975. The pattern of reproduction in female Columbian black-tailed deer, Odocoileus heminonus columbianus. |. Reprod. Fert. 44:261-272. TrauceEk, D. L. AND A. O. HaucEN. 1965. Corpora lutea variations of white-tailed deer. J. Wildl. Manage. 29:487-492. Florida Scient. 58(1):; 25-31. 1995. Accepted: October, 1994. 39 FLORIDA SCIENTIST [VOL 58 Chemical Sciences ATTEMPTED USE OF CHIRAL COPPER(UI) AND NICKEL(II) CATALYSTS FOR ENANTIOSPECIFIC CARBENE INSERTION VENKATRA] NARAYANAN, LEON MANDELL, AND DEAN F. MARTIN ~ Institute for Environmental Studies, Department of Chemistry, University of South Florida, Tampa, Florida 33620 Asstract: Metal complexes having a chiral carbon center can precisely discriminate between enantiotropic atoms, groups, or faces in achiral molecules and catalyze production of a broad array of natural and synthetic substances of excellent enantiomeric purity. This work describes attempts to use as catalysts metal complexes of the type M[RCOCHC(NR")R']:, which have overall chirality and which can be resolved. Nickel(II) and copper(II) compounds were studied. The former, when resolved, have smaller racemization rates, but they did not catalyze the reaction of interest at reasonable yields. The copper(II) compounds catalyzed the desired reaction, but the enantiomeric purity was poor, presumably because of the rate of racemization of the chiral catalyst. FLORIDIANS generally are not aware of chiral syntheses, though they may find the products useful (Borman, 1990; Chan, 1993; Stinson, 1994). A chiral synthesis is one which produces a good yield of one enantiomeric isomer. The isomer obtained is significant because physiological properties can differ significantly, and some examples are listed (Fig. 1). One form of a certain compound is called aspartame and is a sweetener, whereas its isomer is bitter. The R-isomer of thalidomide is a sedative and a hypnotic, whereas the S-isomer is a potent teratogen. Thus synthesizing only the correct enantiomer would have saved misery. Economics can be involved, as in the extreme case when one form is active (S-ibuprofen, apain relieverin Motrin, N uprin, and Advil) and the other (R-isomer) is inactive. By synthesizing the desired isomer instead of the normal 50%-50% mixture, one can get more “bang for the buck.” [In the last example, the R-isomer is converted to the S-isomer in the body. ] The first metal-catalyzed asymmetric reaction of prochiral compounds was reportedly achieved in 1966 (Noyori, 1990, Lowenthal et al., 1990). A chiral Schiff base-copper(II) compound, bis-[N- (+)-a-phenylethylsalicylaldimato) |copper(ID) (Fig 2, compound 1), was found to catalyze the enantioselective carbenoid reaction between styrene and ethyl diazoacetate to give cis- and trans-2-phenylcyclo- propanecarboxylates (Fig 2, compound 2), in less than 10 % enantiomeric excess (ee) (Noyori, 1990). Subsequently, chiral cyclopropanation was achieved using bisoxazoline and copper(I) derivatives (Lowenthal et al., 1990, Lowenthal and Masamune, 1991; Evans et al., 1991, 1992; Maller et al., 1991) with quantitative selectivity (Evans et al., 1991). The preparative value of modified carbenes produced by copper-catalyzed decomposition of diazoalkanes is due to their highly discriminative reactivity (Nozaki 33 No. 1 1995] NARAYANAN, ET AL.—ATTEMPTED USE OF COPPER AND NICKEL Optical Isomer 1 Optical Isomer 2 H2N ot HRN, H PhC H3 CO2H i CO2H (R)-phenylalanine (S)-phenylalanine Sweet Bitter AA aK i = ‘i VAN = r cal Gg HOC NH ~CO,Me N-a-(S)-Aspartyl-( S)-phenylalanine methyl ester ie a edeg peice hal pao a (Aspartane) Z Bitter Sweetener OH O2 ©2 = Ci2CHC(O)NH OH SAE OH 2,2-Dichloro-N-( S)-{(S)-2-hydroxy-1 (hydroxymethy!)- 2,2-Dichioro-N-{ R)-{(R)-2-hydroxy-1 (hydroxymethyl)- 2-(4-nitrophenylethyl}-acetame (chloramphenicol) Antibacterial Oy~ COH> (R)- Thalidomide (S)-Thalidomide Potent teratogen Sedative and hypnotic Fig. 1. Comparison of the physiological properties of selected optical isomers (after Chan, 1993) O 0 © foe IK YR aN, Q com ZN) Day ye 4 © © o Fic. 2. Structures of compounds considered. Compound 1, Bis-[N-(-)-a phenylethyl- salicylaldiminato|copper(ID); compound 2, . cis- and trans-2-phenylcyclopropanecarboxylic acid; com- pound 3, bis-(1-phenylimino-1,3-diphenylpropane-3-one]metal(II); compound 3a, copper(II) derivative; compound 3b, nickel(II) derivative. 34 FLORIDA SCIENTIST [VOL 58 et al., 1966). The mechanism of the reaction described was proposed to be a nucleophilic attack of the reactive carbene (of the diazo compound) on the copper center, forming a coordinate bond to a fifth coordinating atom; nitrogen is then evolved. The formation of the copper carbene transition state is supposed to be the key step in the formation of the three-membered ring. The carbene-copper complex then is presumed to react with the styrene double bond initiating the formation of two carbon-carbon bonds, to form a three-membered ring. Because of this, we wished to see how a catalyst for which the chirality Henved from asymmetry of the complex itself, rather than a substituted chiral ligand, would effect the enantiospecificity of the carbene insertion. Toward that end, we prepared a catalyst using compounds of the type [RCOCHC(=NR')R"|:M, where M is copper(II) and nickel(II), that deviate from planarity and thus have overall chirality. Materials of this type are resolvable into enantiomeric forms (Moeller and Gulyas, 1958;Hseu et al., 1963) by column chromatography using D-lactose in benzene. METHODS AND MaTERIALS—AIl compounds were obtained from Aldrich Chemical Company. Melting points were uncorrected. Synthesis of coordination compounds—Bis(1-phenylimino-1,3 diphenylpropane- 3-ono)-copper(II) -nickel(II) (Fig. 2, compound 3a,b) were prepared as before (Hseu et al., 1963; Struss and Martin, 1966). Bis-[N-(-)- a -phenylethyl- salicylaldiminato]copper(II), (Fig 2, compound 1) was prepared in two steps. Racemic a-methylbenzylamine was resolved (Ault, 1965), and the levorotatory isomer was converted into the coordination compound following the published procedure (Sacconi and Ciampolini, 1964). Resolution of chiral coordination compounds —The copper(II) compound (3a. Fig 2) was resolved using D-lactose in benzene (Hseu et al., 1963) in a 200-cm column (1.0-cm diameter)and eluting at a rate of 0.4 mL/min. Breakthrough was established by visual examination. All optical measurements were made at 598.3 nm with a Perkin-Elmer polarimeter (241MC). Readings were reproducible to + 0.003. Average weight of each 0.5-mL fraction was determined colorimetrically. Maximum values for specific and molecular rotations, respectively, were: +51,+330; -67, -440, with the dextrotatory fraction eluting first. Asymmetric synthesis using coordination compounds as catalysts (Nozaki et al., 1966)—Styrene (8.88 g., 0.085 mol) and compound 1 (Fig. 2) (0.26 mmol) in a 3- necked flask equipped with dropping funnel, condenser, and stirrer, were stirred for 20 min at 50°. The temperature was raised to 80°, and ethyl diazoacetate was added during a period of one hour, and the temperature was maintained for an additional 30 min. The cooled mixture was worked up using ethanol (20 mL) and 50 mL of 30% (v/v) aqueous ethanolic KOH (1.3 M). Base was added over a 10-min period, and the hydrolysis mixture was stirred for 12 hours. Evaporation under reduced pressure (50°, 124 mm) yielded a residue that was extracted with two 20-mL portions of hexane, then with 5 mL of 3 M HCl. The mixture was extracted with three 20-mL portions of dichloromethane, and the combined organic extracts were dried (sodium sulfate), then stripped. The infrared and nuclear magnetic resonance spectra of the residue agreed with literature values (Sadtler, 1968, 1971). The reaction was No. l 1995] NARAYANAN, ET AL.—ATTEMPTED USE OF COPPER AND NICKEL 35 TaBLe 1. Yields of cis- and trans-2-phenyleyclopropanecarboxylic acid in the presence of compounds of the type [o-CsHs1O(CH=NR)|2M R M(II) Yield,% PhCHMe Ni 19 PhCHMe Cu ak) 0.5{(CH2)sCH(COOMe) | Cu 58 a: sees 20 TABLE 2. Yields of cis- and trans-2-phenylcyclopropanecarboxylic acid in the presence of compounds of the type [RCOCHC(NR')R")2M R' R" M(II) Yield,% Ph Cu 62 Ph Ni 32 Me _ 0.5[(CH2CHCH2] Cu 58 TABLE 3. Polarimetric data for cis- and trans- 2* samples obtained from experiments in which optically active complexes were used. Catalyst used Observed rotation,° specific rotation,° dextro- 3 -0.011 -0.084 levo - 3 -0.007 -0.06666 -(S)-2 -0.918 -18.3 repeated using optically active fractions of compound 3a (Fig. 2), but the final products were dissolved in chloroform and analyzed for optical activity (Table 3). Approximate racemization rates—A resolved sample of compound 3a (Fig. 1) in benzene was heated at 82° for 0.5 hr, cooled to room temperature, and the optical activity changed from -0.045 to -0.015 (corresponding specific activities decreased from -38 to -11), whereas at room temperature the other sample changed from 0.059 to 0.055 (specific activity changed from -49 to 37.5) during a 2-hr period. RESULTS AND DiscussioN—The series of coordination compounds prepared were tested as catalysts for the synthesis of cis- and trans forms of compound 2 (Fig. 1) from styrene and ethy] diazoacetate. The yields, using unresolved compounds, are recorded (Table 1, 2). Based upon these results, bis(1-phenylimino-1,3 diphenylpropane-3-one |copper(II) (Fig. 2, compound 3a) was selected for further study. It was resolved by column chromatography using D-lactose in benzene (Hseu et al., 1963), and the results are summarized (Table 3). Specific rotations for 36 FLORIDA SCIENTIST [VOL 58 products using resolved fractions exceeded experimental error, but were negligible when compared with the copper catalyst used by Nozaki and co-workers (1966). Based on these results, we conclude that a specific chiral center, containing an asymmetric carbon in the ligand, was much more effective in effecting asymmetric synthesis than was a compound with an overall chirality of either enantiomer. It is possible, however, that there was an insufficient amount of compound 3a (Fig. 2) present during the reaction. The specific rate constant for racemization for 1 was 0.39 hr at 23-25° in benzene, but we have no value for this constant under reaction conditions. The nickel(II) analog (3b, Fig. 2) should have a greater tendency toward chirality, and the stability was much greater (the specific rate constant for racemization was 0.125 hr) (Hseuetal., 1963), but the yield of product was half of that when we used the copper compound (3a, Fig. 2). It is plausible that more stable bonds would be formed with nickel(II) compounds, which exhibit well- defined six-coordinate states, and decomposition of the carbene complex would be slower. A reasonable explanation for our lack of success is the racemization rate is too great at this temperature. The approximate racemization rate constant in benzene at 82° was 2.5 hr-1, which would indicate that 70% of the copper catalyst (3a, Fig. 2) would racemize during one-half hour at this temperature. We believe that discovering a more stable chiral copper complex could lead to the utility of the approach we have proposed. ACKNOWLEDGMENTS—The authors are grateful to the University of South Florida President’s Council for financial assistance. We appreciate the assistance of Patricia M. Dooris , who served as Consulting Editor, and we are grateful for a careful reading by Dilna Victor and Barbara Martin. LITERATURE CITED AuLtT, A. 1965. Resolution of D, L-a-phenylethylamine. J. Chem. Educ. 42, 269. Borman, U. 1990. Chirality emerges as key issue in pharmaceutical research. Chem. Eng. News 68: (July 9) :9-14. Cuan, A.S.C. 1993. An new route to important chiral drugs. Chemtech. 23: 46-51 Evans, D.A., K.A. WoERPEL, M.M. HINMAN AND M.M. Faut. 1991. Bis(oxazolines) as chiral ligands in metal-catalyzed asymmetric reactions. Catalytic, asymmetric cyclopropanation of olefins. J. Am. Chem. Soc. 113: 726-728. , K.A. WoERPEL AND M_J. Scott. 1992. “Bis(oxazolines)’ as ligands for self-assembling chiral coordination polymers—Structure of a copper(I) catalyst for the enantioselective cyclopropanation of olefins. Angew. Chem. Int. Ed. Engl. 31, 430. Hseu, T.M., D.F. Martin AND T. MOELLER. 1963. Partial resolution of some copper(II) and nickel(II)B- ketoimine compounds by means of a chromatographic technique. Inorg. Chem. 2: 587-590. LowENTHAL, R.E., A. ABIKO AND S. Masamune. 1990 . Asymmetric cyclopropanation of olefins: Bis- oxazoline copper complexes Tetrahedron Lett. 31: 6005- 6008. AND S. MasAMUNE. 1991. Asymmetric copper-catalyzed cyclopropanation of trisubstituted and unsymmetrical cis-1,2-disubstituted olefins: modified bis-oxazoline ligands. Tetrahedron Lett. 32: 7373-7376. MU.er, D., G. Umpricut, B. WEBER AND A. Prattz. 1991. 21. C2-Symmetric 4,4', 5,5'- tetrahedrobi(oxazoles) and 4,4',5,5'- tetrahydro-2,2'-methylenebis(oxazoles) as chiral ligands for enantioselective catalysts. Helv. Chim. Acta 74, 232-239. MOELLER, T. AND E. Gutyas. 1958. The partial resolution of certain inner complexes by means of a chromatographic technique. J. Inorg. Nucl. Chem. 5: 245-248. No. l 1995] NARAYANAN, ET AL.—ATTEMPTED USE OF COPPER AND NICKEL Wi Noyori, R. 1990. chiral metal complexes as discriminating molecular catalysts. Science 248: 1194-1199. Nozaki, H., S. Moriuti, H. Takaya AND R. Noyort. 1966, Asymmetric induction min carbenoid reaction by means of a disymmetric copper chelate. Tetrahedron Lett. 43: 5239-5244. Sacconl, L. AND M. CiAMPoLini. 1964. Pseudo- tetrahedral structure of some a-branched copper(II) chelates with schiff bases. J. Chem. Soc. 276-280. SapTLER. 1968. 1971. The Sadtler Standard Spectra, Sadtler Research Labs, Philadelphia, PA, Vols. 6, 9. Stinson, S.C. 1994. Chiral drugs. Chem. Engn.News 72 (38):38-42, 44, 46, 48, 50, 57-58, 60-62. Srruss, A.W. AND D.F. Martin. 1966. Bis(4-imino-2-pentanonato)-copper(II) and bis(3-phenylimino- 1-phenyl-butanonato)-copper(II). Inorganic Syntheses 8: 2-4. Florida Scient. 58 (1): 32-37. 1994. Accepted: October 4, 1994 38 FLORIDA SCIENTIST [VOL 58 Biological Sciences VERVET MONKEYS IN THE MANGROVE ECOSYSTEMS OF SOUTHEASTERN FLORIDA:PRELIMINARY CENSUS AND ECOLOGICAL DATA WILLIAM R. HYLER 3020 S.W. Ist Avenue, Gainesville, Florida 32607 Apstract: Observations were made on free-ranging, introduced troops of the vervet monkey (Cercopithecus aethiops) in the mangrove communities of southeastern Florida. The founder popula- tions were animals released from unsuccessful tourist attractions. Census information was obtained for two troops. An analysis of the vervets’ time budget shows resting (36.9%) and foraging (35.2%) predominate. The distribution data on food sources reveal a reliance on seeds (23.2%), flowers (21.8%), fruit (20.2%), and invertebrates (17.4%). Tus study was directed by the concerns of the Broward County Parks and Recreation Department, the focus being Westlake Park in Dania, Florida. The park was established in 1962 as part of the parks system. Wild, non-native monkeys inhabit the park and are the descendants of animals released in the mid-1950’s and early to mid-1970’s by the proprietors of failed tourist attractions. In the past, as many as four species of primates may have lived within park boundaries (MacAdam, 1994). The objectives of this study were to ascertain what species of monkeys still inhabit the park, census the population(s), and identify their food sources. At the conclusion of the first stage of this study, with approximately 70% of the park area covered, only vervet monkeys have been observed. Metuops—Study site—The parkis primarily a mangrove ecosystem covering approximately 3,700 hectares, located 1.2 kilometers west of the Atlantic Ocean. The salinity of the park’s water is 30 parts per thousand (MacAdam 1994). Consequently, the predominant plant species are mangroves: black mangrove (Auicennia germinans), red mangrove (Rhizophora mangle), and white mangrove (Languncularia racemosa). The gross geographic features of the park are those of the typical mangrove swamp, with the exception of the superimposition of a grid-like network of drainage canals and mosquito control ditches. The climate in the area is characterized by warm weather, light but persistent winds, and more than 1524 mm of annual rainfall (Ferguson 1985). Study animal—The study species was the vervet monkey, Cercopithecus aethiops, amember of the largest Family of Old World monkeys, the Cercopithecidae. Lernould (1988) classifies the vervet as a super species consisting of four species: C. aethiops, C. pygerythrus, C. sabaeus, and C. tantalus. This same source lists 21 subspecies of the primary four species. Kingdon (1971) states that hybridization is common in both wild and captive populations. According to Kingdon, interbreeding between C. tantalus and C. pygerythrus has occurred in southern and western Uganda, resulting in hybrids. After comparing current study photographs to Dorst (1970) and Kingdon (1971), it seems probable the study groups were composed of such hybrids. Data collection—The study was conducted from 27 July 1991 to 26 August 1992, resulting in 731 scan samples. Contact was made on the first day with a troop of vervets. They were designated A Group, in reference to the area of the park they inhabited. Eleven days later the first observations of another troop of vervets was made. This second troop was designated T Group, since it obtained supplemental food at a trailer court near the park. Due to the inaccessibility of A Group, I decided at the beginning of February 1992 to concentrate observational efforts on T Group. Four months were needed to No. 1 1995] HYLER—VERVET MONKEYS IN THE MANGROVE ECOSYSTEMS 39 TABLE 1. Census information. Values represent means. Group Adult male Adult female Juvenile Infant Total A(1) 3 5 3 2 13 mC) 4 6 4 5 19 T(2) 5 9 4 5 23 A(1) Census information from 27 July 1991 through 17 February 1992 T(1) Census information from 7 August 1991 through 22 May 1992 T(2) Census information from 23 May 1992 through 26 August 1992 TABLE 2. Time budget. Activity % Resting (A) 36.9 Locomotion (B) 19.3 Social behavior (C) 8.6 Foraging (D) 30.2 100.0 (A) Pausing for extended periods (not feeding, not socializing). (B) All movement not directly associated with foraging, including travel between food trees. (C) All interactions between individuals. (D) Movement associated with feeding, plucking, peeling, inducing food into mouth. habituate the monkeys. Data were collected by scan sampling every fifteen minutes, allowing fifteen seconds per observed individual in the troop (Altmann, 1974). The data sheet used to record observations was constructed after Hinde (1973). Individual recognition, when possible, was based on study photographs and a field identification sheet for the notation of physical characteristics. Further identification was derived from Lehner (1979) and food typology was adapted from Kavanagh (1978). 40 FLORIDA SCIENTIST [VOL 58 TABLE 3. Dietary components by food class. Food class Number of observations % Seed 170 23.2 Flower 159 21.8 Fruit 148 AQ) 2 Invertebrates NPAT 17.4 Foliage 110 15.0 Pith 15 Delt Gum/bark 2 0.3 NS Jel 100.0 TABLE 4. Complete list of all observed food items from both groups (food typology from Kavanagh, 1981). Food part * Food source flw frt fol g/b pth sed inv Black mangrove x x Button wood x Gumbo limbo X Red mangrove x x x x x % White mangrove x x x Ss Brazilian pepper x Shelf fungi x Periwinkle x Ants x Caterpillars | x Damsel fly x Moths x Pupae/grub x ° flw, flower; oth, pith; frt, fruit; sed, seed; fol; foliage; inv, invertebrate. g/b, gum/bark; No. 1 1995] HYLER—VERVET MONKEYS IN THE MANGROVE ECOSYSTEMS 4] RESULTS AND DiscusstoN—Population numbers are derived from scan samples. The numbers listed in Table 1 are the means. In using the means I acknowledge that visibility difficulties have forced me to assume that the sexes were not differentially visible. Census dates for T Group show an arbitrary division on my part just prior to the 1992 birthing season. The time budget for the study troops is shown in Table 2 Table 3 gives the dietary components by class and represents the combined observations of both study groups as recorded within park boundaries. The same is true for Table 4, which gives the dietary breakdown by source and part. Neither Table 3 nor Table 4 show the daily food supplements provided by an individual who distributed fruit to the T group; therefore, the dietary tables are representative of only those foods procured by foraging. A vervet troop will generally be made up of 1 to 7 adult males and 2 to 10 adult females with the accompanying juveniles and infants (Cheney and Seyfarth, 1990). This multi-male and age-graded group will range from 7 to 53 with a mean of 24 monkeys (Struhsaker, 1967). Table 1 shows that both study groups fall within these parameters. The mean sex ratio of 1:1.7 for the two troops conforms well to field reports for this species (Hall and Gartlan, 1965; Struhsaker, 1967; Galat and Galat- Luong, 1976; Cheney and Seyfarth, 1990). Table 1 also shows that a combined average of 60% of adult females from the two troops were with infants. This birthing rate falls within established ranges (Struhsaker, 1967; Gartlan, 1969; Turner et al., 1987). Although direct comparisons of the vervets’ time budget (Table 2) are not possible due to differences in data collection methods, this study and previous ones are analogous (Dunbar and Dunbar, 1974; Galat and Galat-Luong, 1976; Kavanagh, 1981; Harrison, 1985). Richard (1985) defines primates who quickly or dramatically alter their diet as opportunists. In a survey of 131 primates, Harding (1981) found that the vervet monkey has one of the most omnivorous diets of all the primates, thus earning it the title of opportunistic omnivore (Gautier-Hion, 1988). The vervets’ dietary adaptabil- ity is further enhanced by the lack of specialization in motor patterns associated with feeding techniques (Kavanagh, 1981). The vervetis classified as semi-arboreal, semi- terrestrial, being limited in its range only by water and the availability of sleeping trees (Cheney and Seyfarth, 1990). This ability to feed on the ground, as well as in the trees, affords the monkeys a varied diet. Table 3, which gives the diet for this study shows that the Florida vervets’ diet is consistent with other field studies (Dunbar and Dunbar, 1974; Galat and Galat-Luong, 1976; Kavanagh, 1981; Wrangham and Waterman, 1981; Harrison, 1984). The three mangrove species in the study area provided a substantial percentage of the vervets’ diet, especially the red mangrove (Table 4). Galat and Galat-Luong (1976) noted that the red mangrove and the white mangrove species were the most frequently exploited plant species in their study of the mangrove swamps of Senegal, Africa. 492 FLORIDA SCIENTIST [VOL 58 This preference is most likely due to the red mangrove’s use of a salt exclusion mechanism to maintain salt balance. The black mangrove and the white mangrove use a salt excretion method (Scholander et al., 1962). The difference in the maintenance of salt balance translates into a salt sap concentration that is as much as ten times lower for the red mangrove (Atkinson et al., 1967). Mangrove leaves contain secondary compounds which curtail the nutritional content of polysaccharides and soluble plant proteins. They also disrupt the opera- tion of symbiotic and digestive enzymes in the vervets’ gut (Swain, 1979). Vervets are able to consume the foliage of mangroves by eating the immature leaves (Wrangham and Waterman, 1981; Harrison, 1984). In this study roughly 60% of the parts of red mangrove consumed were budding leaves and/or shoots. Invertebrate food items constitute an important source of protein and fat for the vervet that is not supplied by the other components of their diet (Harrison, 1985). Table 3 shows that 17.4% of the two study groups’ diet were invertebrates (pupae, grubs, caterpillars, ants). While Kavanagh (1981) stated that vervets are not adept at catching flying insect forms, on numerous occasions in this study juveniles were observed catching damsel flies on the wing. MacClaud (1906) mentioned that vervets frequently consumed crabs and Galat and Galat-Luong (1976) reported daily hunts for fiddler crabs (Uca tangeri). This study recorded no observations of vervets consuming crabs; however, on several occasions fresh carcasses of the mangrove tree crab (Aratus pisonii) were found with open abdomens and the interior eaten away in the manner described by Galat and Galat-Luong. (1976). Study observations show comparable behaviors between the two introduced troops and previous studies of native or long established transplanted vervet populations. Future research will thoroughly investigate the release dates of the Westlake vervets for a clearer picture of the monkeys’ population growth rate. ACKNOWLEDGMENT —I would like to thank the commissioners of Broward County, Florida for allowing me access to Westlake Park. Iam extremely grateful to Gil MacAdam for his continued support. A special thanks is due to Godfrey Bourne and Colin Chapman. | also would like to thank the anonymous reviewer for the constructive comments. LITERATURE CITED ALTMAN J. 1974. Observational study of behavior: sampling methods. Behaviour 49:227-267. ATKINSON, M., G. Finp.ay, A. Horr, M. Pitman, H. SADLER AND H. West. 1967. Salt regulation in the mangroves Rhizophora mangle Lam. and Aerialitis annulata R. Aust. Jo. of Biol. Sci. 20:589-599. CHENEY, D. AND R. SEYFARTH. 1990. How Monkeys See The World. Univ. of Chicago Press, Chicago, IL. Dorst, J. 1970. A Field Guide to Larger Mammals of Africa. Houghton Mifflin Company, Boston, MA. Dunpar, R. aND E. Dunspar. 1974. Ecological relations and niche separation between sympatric terrestrial primates in Ethiopia. Folia primatal. 21:36-60. FERGUSON, G.E. 1985. Water Resources of Southeastern Florida. Department of the Interior, United States Government Printing Office, Washington, D.C. Ga.at, G. AnD A. Gatat-Luonc. 1976. La colonisation de la mangrove por Cercopithecus aethiops No. 1 1995] HYLER—VERVET MONKEYS IN THE MANGROVE ECOSYSTEMS 43 sabaeus au Senegal. La Terrer et La Vie: Rev. d’Becol. Appl. 30:3-30. GartTLANn, J. 1969. Sexual and maternal behavior of the vervet monkey, Cercopithecus aethiops. ]. of Reprod. Fert. 6:137-150. Gautier-Hion, A. 1988. The diet and dietary habits of forest guenons. Pp. 257-283. In: GAuTIER-HIoN, A. (ed.), A Primate Radiation: Evolutionary Biology of the African Guenon. Cambridge Press, Cambridge, UK. HALL, K. anp J. GartLan. 1965. Ecology and behavior of the vervet monkey (Cercopithecus aethiops) , Lolui Island, Lake Victoria. Proc. Zoo. Soc. London. 145:37-56. Harpinc, R. 1981. An order of omnivores: Non-human primate diets in the wild. Pp. 191-214. In: HarDING, R. AND G. TELEK!I (eds.), Omnivorous Primates: Gathering and Hunting in Human Evolution. Columbia University Press, New York. Harrison, M. 1984. Optimal foraging strategies in the diet of the green monkey (C. aethiops) at Mt. Assirik, Senegal. Internat. J. Primat. 6(4):351-376. . 1985. Time budget of the green monkey (Cercopithecus sabaesus): Some optimal strategies. Internat. J. Primat. 7(2): 201-213. Hinpe, R. 1973. On the design of check sheets. Primates 14(4): 393-406. Kavanacu, M. 1978. The diet and feeding behavior of Cercopithecus aethiops tantalus. Folia primatol. 30:30-63. . 1981. Variable territoriality among tantalus monkeys in Cameroon. Folia primatol. 36:76-98. Kincpon, J. 1971. East african mammals: An atlas of evolution in Africa. Academic Press, New York. Leuner, P. 1979. Handbook of ethological methods. Garland STPM Press, New York. LERNOULD, J. 1988. Classification and geographical distribution of guenons: A review. Pp. 54-77. In: Gautier-Hion, A. (ed.), Evolutionary Biology of the African Guenons. Cambridge University Press, Cambridge, UK. MacApaM, G. 1994. Personal Communication. Broward County Parks and Recreation Department, Oakland Park, FL. MacC.oup, C. 1906. Notes sur les mammiferes el les oiseaux de l'Afrique occidentale: Casamance, Foutadjalon, Guinee francaise et portugaise. Paris, Viletle. RicHarD, A. 1985. Primates in Nature. W.H. Freeman and Company, New York. SCHOLANDER, P., H. HAMMEL AND E. HEMMINGSEN. 1962. Salt balance in mangroves. Plant Physiol. 37:722-729. STRUHSAKER, P., H. HAMMEL AND E. HEMMINGSON. 1967. Social structure among vervet monkeys. Behaviour 29:83-121. Swain, T. 1979. Tannins and lignins. Pp. 657-682. In: RosENTHAL, G. AND D. JANZEN (eds.), Herbivores: Their Interaction with Secondary Plant Metabolites. Academic Press, New York. TUNRNER, T., P. WHITTEN, C. JOLLEY AND J. ELsE. 1987. Pregnancy outcome in free-ranging vervet monkeys (Cercopithecus aethiops). Amer. J. Primatol. 12:197-203. WrancuaM, R. AND P. WaTERMAN. 1981. Behavior of vervet monkeys on Acacia tortilis and Acacia xanthophloea: with special reference to reproductive strategies and tannin production. J. Animal Ecol. 50:715-731. Florida Scient. 58 (1): 38-43. 1995. Accepted: October 7, 1994 A4 FLORIDA SCIENTIST [VOL 58 Chemical Sciences MEXICO: AN ALTERNATIVE SOURCE OF MERCURY CONTAMINATION IN FLORIDA’S BIOSPHERE Jay W. PALMER Institute For Environmental Studies Department of Chemistry, University of South Florida, Tampa, Florida 33620 ApstracT: It is suggested that the major source of mercury for the contamination of Florida’s biosphere results from the use of mercury in silver refining in Mexico during 1550-1900 A.D. Since Florida is downwind from Mexico, volatilized mercury rained down on Florida (1550-1900) to become immobilized in a large organic mercury sink. However, clearing and burning of underbrush, draining of swamps for large-scale farming, and construction of roadways and living communities over large areas have resulted in air oxidation of organic matter in the mercury sink, liberating mercury to be volatilized back into the atmosphere. This mercury is becoming a problem in Florida’s biosphere. IN RECENT years, there has been considerable media publicity concerning real or perceived increasing amounts of mercury in the Florida biosphere. Theories on potential sources include fossil fuel-burning power plants, garbage incinerators, medical waste incinerators, massive drainage of low-lying lands and agricultural practices as well as past use of mercury-containing farm chemicals. Even the suggestion has been made that we look “upwind” for possible sources of contamina- tion (Baker, 1994; Brunais, 1994; Gunter, 1993). Elevated mercury levels in the biosphere, especially in fish, are of concern in Florida, because of the direct health threat to humans, other mammals, and birds which consume mercury contaminated fish. By early 1989, health advisories had been issued for nearly 800,000 hectares of Florida fresh waters, warning consumers of the health risk of eating fresh water fish (Lange et al., 1993). Nearly all of the mercury in fresh water fish is methyl mercury. However, the influence of physical and chemical variables on mercury accumulation in fish varies greatly, indicating localized effects play an important part in the biological availabil- ity of mercury. Lack of data on atmospheric deposition and sediment profiles in Florida precludes determination of the influence areal transport has on mercury concentration (Lange et al., 1993). Thus, it is imperative to investigate Bepetua: mercury sources upwind of lgnde In a recent article (Renberg et al., 1994), evidence is presented that silver smelters had been spewing lead and other toxic metals into the atmosphere for more than 2,000 years before the Industrial Revolution, leaving a toxic fallout that remains a threat to modern humans. This included a significant increase with the beginning of silver production in the New World. Perhaps we should look there for our major source of mercury in Florida. When Mexico was conquered by Hernan Cortes’ Conquistadors and Indian allies in 1521, Aztecs were already working silver deposits in two of Mexico’s richest No. 1 1995] PALMER—MEXICO: AN ALTERNATIVE SOURCE OF MERCURY 45 areas, Taxco and Pachuca. The Spaniards increased mining as quickly as possible, and by 1550 had also discovered rich silver deposits in San Luis Potosi, Zacatecas, and a most important one in Guanajuato (Motten, 1972:14). The Spanish brought technical knowledge including that of the Germanic countries which was the best in Europe. However, refining of silver was only economical with rarer, high-grade silver ores. Most Mexican silver ores were not very rich but were plentiful. When Spanish smelting and refining processes soon proved inadequate, a Spaniard named Bartolomé de Medina commercialized a profitable new process for silver extraction from low-grade ores, called patio amalgamation. Medina is usually given credit for discovering the process in 1557; however, he did not discover amalgamation for the ancient Greeks knew of it, and his process was in commercial production by 1555 (Motten, 1972:21-22). Even though the Patio Process is often called the Cold Process, heating of ores was not completely discontinued when the character of the ores and the presence of ample fuel supplies allowed traditional smelting. In other cases, including some using the Patio treatment, roasting was considered a necessary preliminary step. In every case though, the first step was to reduce silver-bearing ore to pebbles small enough to pass through a screen made of a cow’s hide punctured with holes. This preliminary crushing was usually done by women hammering the rocks apart (Motten, 1972:22). At this point, high-grade ores were set aside for smelting, and lower-grade ores were placed in mills for pulverizing. These mills were usually floored and walled with hard basalt. At the center was a hole in which a post was fixed with a suspended boom to which heavy basalt blocks were attached. The front end of the mill was tipped so that ore pebbles could slide under and receive full crushing action. Arranged in batteries, the mills were operated by relays of mules pulling the boom around until the ore was the texture of fine sand. Then water was added to make a slime. Contents of the mills were dumped onto great flagstone patios sometimes as large as two acres. When piles had been accumulated to a depth of two feet and often as large as 100 feet in diameter, the azoquero (metallurgist) began his work (Motten, 1972:23). The azoquero had to determine the basic characteristics of the slime. To some slime he added salt, others lime, and still others roasted copper pyrites. After these adjustments, mercury was added. Mercury was expensive because it was a crown monopoly and very scarce, so the azoquero was very careful how much he added. Usually it was about 6 times the amount of silver he expected to extract (Motten, 1927:23-24). The patio process was slow because it depended upon rainfall and temperature. Sometimes it would take 5 months, although 5 weeks was more common. Other times, the azoquero would heat the mass; and still others, he would add more mercury. Finally, when he felt the amalgamation was complete, the cake was scraped up and washed in large vats. The heavy silver amalgam and excess mercury would settle to the bottom, and the water and tailings drawn off. The amalgam was separated from liquid mercury by squeezing the mixture through cloth sacks and molding it into little pyramids placed on a metal platform under which a charcoal fire was built. Originally, heat forced the mercury to evaporate into the atmosphere as AG FLORIDA SCIENTIST [VOL 58 gaseous atoms. Eventually all mercury was driven off leaving relatively pure silver behind but one containing a small percentage of gold (Motten, 1972:22-24). The initial process was very wasteful due to the atmospheric loss of mercury; however, in 1575 Juan Capellin, devised a bronze, bell-like hood (now called a Capellina) that was placed over the amalgam before it was heated. The heat forced the mercury to evaporate, but contact with the cool bell caused it to condense and run down the inside, where it dropped off into a little trough (Motten, 1972:24-27). While this substantially reduced the amount of mercury evaporating into the atmosphere, some continued to be lost in all phases of processing. In 1788-1798, German miners led by Elhuyar and Sonneschmid attempted to develop a faster more efficient silver refining method called the Born Process; but it turned out to be more inefficient and wasteful of mercury than the Patio Process. Finally in about 1850, a modified Born Process called Barrel Amalgamation was developed and re-introduced in Mexico. Again, the process proved to be more inefficient and wasteful than the Patio process, but also more profitable. Both processes continued to be used very profitably until they were superseded about 1900 by the Cyanide Process (Motten, 1972:47-48,53). Some appreciation of the amount of mercury vaporized into the atmosphere can be gained from the amount of silver shipped to Europe. When the first trickle began in 1500, an estimated 20,000 tons of silver was in circulation in Europe. By 1650, this amount was almost doubled with Mexico accounting for about two-thirds of the shipments (Kandell, 1988:184-185). Thus, since Florida is downwind of Mexico, much of the mercury volatilized during silver refining from 1550 to 1900 may have rained down on Florida. However, since Florida consisted of a lush countryside with much decaying vegetation, this mercury was immobilized by organic materials to form a mercury sink (Schroeder et al., 1991; Westling, 1991). By 1900, the lush Florida vegetation was being cut down and burned; large swamp areas were being drained for large scale farming; enormous acreages were being converted to new living communities and roadways. The exposure of these soils to the atmosphere resulted in increased oxidation and loss of organic matter which eventually turned the mercury sink into a mercury source (Westling, 1991). This is still taking place - mercury that might have rained on Florida during 1550 to 1900 and was immobilized in an organic sink, now has been liberated and is being volatilized back into the atmosphere. Of course much of the volatilized Mexican mércury may also have been deposited on eastern Mexico and in the Gulf of Mexico en route to Florida, as well as in the Atlantic Ocean along the northeast coast of North America. Mercury analyses have been done on deep-sea fish, Antimora rostrata, collected between 2000 and 3000 m in the western North Atlantic Ocean. In both recent and old fish, mercury increased as a function of length of fish, but comparison of the two concentrations vs. length relationships shows that there has not been an increase in mercury concentration in deep-sea fish in the last century (Barber and Whaling, 1984). However, more analyses are needed, especially from the Gulf of Mexico near the Mexican coast. Perhaps core samples from the floor of the Gulf of Mexico could No. 1 1995] PALMER—MEXICO; AN ALTERNATIVE SOURCE OF MERCURY AT be taken and analyzed for mercury as a function of time of deposition as shown by Carbon-14 analyses. If it can be demonstrated that major mercury contamination occurred many years ago, then attention can be directed towards new methods to reduce mercury volatilization such as selenium treatment (Paulsson and Lundbergh, 1991) or removal of mercury from soil using specialized processes such as steam volatilization. In this way, more fruitful approaches might be devised to solve our mercury problem. ACKNOWLEDGMENT—I wish to thank Professor Robert Braman for his helpful comments on mercury analyses. LITERATURE CITED Baker, D. 1994. High levels of mercury in Broward rain. Tampa Tribune, 20 February. BarBER, R.T. AND P.J. Wuatinc. 1984. Mercury in recent and century-old deep-sea fish. Environ. Sci. Technol. 18:552-555. Brunals, A. 1994. Mercury levels tip the scales away from fish. Tampa Tribune, 2 February. Gunter, B. 1993. Mercury level increasing in Everglades, study says. Tampa Tribune, 5 November. KANDELL, J. 1988. La Mexico, The Biography of Mexico City. Henry Holt and Company, New York. Lance, T.R., H.E.Royats anp L.L. Conner. 1993. Influence of water on mercury concentration in largemouth bass from Florida lakes. Trans. of the Amer. Fisheries Soc., 122:74-84. Morten, C.G. 1972. Mexican Silver and the Enlightenment. Octagon Books, A Division of Farrar, Straus and Giroux, New York. PAULSSON, K. AND K. LUNDBERGH . 1991. Treatment of mercury contamination by selenium addition. Water, Air, Soil Poll. 56:833-841. RENBERG, I.M., W.K. PERRSON AND O. EmTErYD. 1994. Pre-industrial atmospheric lead contamination detected in Swedish lake sediments. Nature 368:323-326. SCHROEDER, W.H., G. YaRWOOD AND H. Nikt. 1991. Transformation processes involving mercury species in the atmosphere. Results from a literature survey. Water, Air, Soil Poll. 56:653-666. WESTLING, O. 1991. Mercury in runoff from drained and undrained peatlands in Sweden. Water, Air, and Soil Pollution. 56:419-426. Florida Scient. 58 (1): 44-47. 1995. Accepted: October 7, 1994 48 FLORIDA SCIENTIST [VOL 58 Biological Sciences POPULATION ESTIMATE OF SPOTTED SKUNKS (SPILOGALE PUTORIUS) ON A FLORIDA BARRIER ISLAND A.E. Kintaw*, L.M. Exruart®, P.D. Doerr, K.P. PoLLock”), AND JAMES E. Hines®) (1)Department of Zoology, Campus Box 7617, North Carolina State University, Raleigh, NC 27695-7617; (2)Department of Biological Sciences, 4000 Central Florida Boulevard, University of Central Florida, Orlando, FL 32816; (3)Department of Statistics, Campus Box 8203, North Carolina State University, Raleigh, NC 27695-8203; (4)Patuxent Wildlife Research Center, U.S. Fish and Wildlife Service, Laurel, MD 20708; *Current address: 99 Hillside Drive, Eustis, FL 32726 Apsract: Mark-recapture experiments on a closed population of spotted skunks (Spilogale putorius) on Canaveral National Seashore (a barrier island) were conducted in 1973-74 to obtain a population estimate; we achieved geographic and temporal closure by choosing a 16-km linear section of the island and a 10 day trapping period. The closed model M,, in the computer program CAPTURE yielded an estimate of 96.0 + 11.2 skunks, yielding a density of 40 skunks/km?, much higher than the only previous estimate from Towa. THE only reported estimate of population density of spotted skunks was 5 skunks/kmm? in an Iowa agricultural area that had ample den sites and an abundance of carrion of Mearns cottontail rabbit (Sylvilagus floridanus mearnsii) scavenged by the skunks (Crabb, 1948). Researchers that have attempted studies have encoun- tered various problems, including inability to catch individuals with hand nets (Patton, 1974); very low population density (McCullough and Fritzell, 1984), loss of ear-tags (Crabb, 1948), and difficulty in obtaining adequate sample size because of insufficient trapping intensity (Kinlaw, 1990). Our objective in this study was to determine if a high density of spotted skunks still occurred in the palmetto scrub as reported by Schwartz (1952) and Manaro (1961). This was timely ecological research with this mustelid since eastern spotted skunk populations have been declining and are now listed as endangered or threatened in many states (Kaplan and Mead, 1991). In 1973-74, one of the authors (LME) conducted a mammal trapping program on Merritt Island National Wildlife Refuge, Brevard County, Florida (Ehrhart, 1976). Recognizing that the geography of the adjacent Canaveral National Seashore would fulfill the geographic component of closure (White et al., 1982), he made an intensive effort to capture intermediate- sized mammals there. Data were analyzed in 1974 using available methods (Ehrhart, 1974). Major advances in analysis techniques of mark-recapture data on closed populations (Otis et al., 1978) allowed us an opportunity to retrospectively re-analyze this dataset and we present our results in this paper. Mark-recapture experiments that deal with large or intermediate-sized carni- vores often involve inadequate sample sizes due to logistic constraints imposed by a species’ large home range or secretive behavior. Historically, many researchers have failed to adequately define their study population (Tacha et al., 1982) or delineate No. 1 1995] KINLAW ET AL.—POPULATION ESTIMATE OF SPOTTED SKUNKS AQ study boundaries (Caughley, 1977). Grossly inaccurate estimates of population size are obtained if geographic or temporal closure of the population is not achieved (White et al., 1982). In particular, the geographic component of closure needs more attention by biologists, as no generally valid analysis exists when animals move in and out of a study stratum (Arnason and Baniuk, 1978), except for a two sample experiment on a closed population (Chapman and Junge, 1956) or for a three sample experiment on a population subject to losses only (Arnason, 1973). Field data are often inadequate when a study is attempted during a season or weather period when the study animal has a low capture probability (Otis et al., 1978). Inappropriate methods of analyses are still being used by some authors when better methods have been developed (Seber, 1982); in particular some mammalogists still use enumera- tion or index statistics over probabilistic capture-recapture models when the popu- lation and survival estimators of the enumeration method have more bias (Nichols and Pollock, 1983). We tried to avoid these pitfalls by first selecting an “island” population. Secondly, in order to have a clear and comprehensive definition of the population we followed the procedure outlined by Kish (1969) that included content, units, time frame, and extent. Our population, then, included all spotted skunks at risk of capture during a 10-day trapping period 20-29 March 1973 within the confines of the southern 16-km section of Canaveral National Seashore, Florida, a barrier island. We used probabilistic estimation models in computer program CAPTURE (Otis et al., 1978) for closed populations that utilize hypothesis testing, goodness of fit tests, and robust estimators to estimate the population size. MaTERIALS AND MEeTHODS—The study site, Canaveral National Seashore (CNS, Fig.1) is an example of a relatively stable, pristine barrier island (Hoffman, 1981). Stout (1979) recognized three plant communities on CNS: coastal dune, coastal strand, and wetlands. Trapping reported in this paper was restricted to the coastal strand community, as extensive year-round trapping on CNS and adjacent Merritt Island National Wildlife Refuge (MINWR) demonstrated that skunks were never taken in wetland habitats (Ehrhart, 1976). Although spotted skunks will occcasionally use open beach dunes (Howell, 1906), both observational (Patton, 1974) and radiotelemetry (McCullough and Fritzell, 1984) studies have demonstrated that skunks rarely use open habitat. Coastal strand is composed of a continuous, dense thicket of woody vegetation that has little grass or forb understory. Saw palmetto (Serenoa repens) is the leading dominant in this community and wax myrtle (Myrica cerifera), buckthorn (Bumelia tenax), and snowberry (Chiococca alba) have high frequencies of occurrence. The seaward border is usually hedged by the salt spray (Stout, 1979). Average width of this community along the 16- km strip is 150 m. An asphalt highway bisects lengthwise the southern 8 km of the Seashore and a foot trail bisects lengthwise the remaining 8 km of the study area. A systematic sampling scheme was used. During March-April 1973, 200 traps were placed in the field with one row 25 m east and one row 25 m west of the road or trail with a north-south spacing of 80 m between traps. Two types of live traps were used: 1) non-collapsible single door Tomahawk traps measuring 25.4 by 30.4 by 81.3 cm, and 2) collapsible double door National traps measuring 22.9 by 66.0 em. Traps were baited daily with commercial cat food. Captured skunks were ear-tagged and weighed; data collected included included sex, weight, age (adult or juvenile), reproductive condition, ectopara- sites, hind foot length, and trap location (Ehrhart, 1976). Before proceeding with the analysis, we had to ensure that the 4 assumptions of the closed CAPTURE models were met: 1) the population is closed; 2) animals do not lose their tags; 3) all marks are correctly noted; and 4) each animal has a constant and equal probability of capture on each trapping occasion. By choosing a short 10-day trapping period on the 16-km strip, geographic and temporal closure of the population was achieved. Since closure should be assessed from a biological basis (Otis et al., 1978), we examined the ratio of average distance between successive captures to overall length of study area 50 FLORIDA SCIENTIST [VOL 58 Atlantic pe Canavera, “7 Canaveral 7 Air Force Station Fic. 1. General map of Cape Canaveral area and (A) detail of the 16 km study area. to determine if the study area was of adequate size; this ratio was less than 3% for both sexes. Tag loss occurred; skunks were recaptured with one or more notches in their ears where tags had torn out, so there was no way to back date to original capture date. We estimated minimum tag retention rates by calculating the percentage of animals recaptured that retained their tags over various time periods. Tag loss was then inferred from the shape of the graph. Since only 4% of tags were lost within 7 days, data were clumped into 7 trap-days out of 10 total days. Marks were assumed to be recorded correctly as they were double-checked during attachment and when animals were recaptured. We used two approaches to determine if catchability was constant. First, we wanted to know if environmental variables might cause time variation in catchability. Trap success (for the entire 1] month trapping period) was first standardized as the daily number of captures of skunks divided by the total number of available traps. The number of captures of other species and the number of inoperable traps No. l 1995 | KINLAW ET AL.—POPULATION ESTIMATE OF SPOTTED SKUNKS 5] TABLE 1. Daily weather variable affecting capture success of Spotted Skunks on Canaveral National Seashore in 1973-74. Variable P value p values < 0.01 Maximum temperature previous day 0.0018 Minimum temperature night of capture 0.0001 Dew point 0.0001 Cloud Cover 0.0161 Standard deviation of barometric pressure 0.0069 P. values > 0.01 Precipitation during 24 hours of capture 0.0759 Wind velocity 0.0914 were first subtracted from the total number of traps before calculating trap success. Trap success was then was used as a dependent variable and regressed against various climatological variables. Weather data were obtained from the National Climatic Data Center, Asheville, North Carolina, and moon phase from the Information Please Almanac. Our second approach to examining catchability was to review results of hypothesis tests provided by program CAPTURE (for the subset of data used to estimate population size). Specifically, we tested for temporal variation (M_ vs M,), behavioral response (M_, vs M,), and heterogeneity (M, vs M,). We feel that the first three assumptions were met as much as possible in a field situation. An advantage in using program CAPTURE for this analysis is that it allows the fourth assumption of equal catchability to be relaxed. ResuLts—Regression analysis demonstrated that 95% of the variability in skunk capture success during this period was explained by five climatic variables : minimum and maximum temperature, standard deviation of the barometric pressure, cloud cover, and dew point (Table 1). The test for time specific variation in trapping probabilities showed strong evidence for time variation (P = 0.001). The test for behavioral response after initial 52 FLORIDA SCIENTIST [VOL 58 capture also provided positive evidence for a behavioral effect (P = 0.023). The test for heterogeneity of trapping probabilities indicated strong evidence that different segments of the population had different capture probabilities (P = 0.001). The model selection procedure ranked model M,, with a 1.00 rating for maximum value and Model M,, as the second best model with a value of 0.97. Since model M,,, had no estimator available, we used the results of the generalized removal estnaten “(pollock and Otto, 1983) under model M,,, N = 96.0 (SE = 11.2), as the population estimate of spotted skunks on the 16-km section of CNS. This equates to an approximate density of 40 skunks/km’ on the 2.43 km? of available habitat. puie test for closure was rejected (P = 0.01). Discuss1on—Weather factors appeared to cause time variation in catchability (Otis et al., 1978), since more skunks were captured on cool, cloudy nights and fewer skunks were captured on hot, clear nights (Table 1). Model M,,, allows behavioral response to first capture (Pollock, 1974). This can accomodate the “trap-shy” response that occurred with females. In behavioral tests, females gave more handstands (a defensive behavior) than males (Zeiner, 1975), and females were less prone to enter our traps. Model M,, also allows this behavioral response to capture to vary with individual animal-so that all members of the population do not exhibit an identical response to first capture (Otis et al., 1978), allowing for differential trap response between males and females. Males were more easily captured and with greater frequency than females. Sex ratio for skunks in this data was 2.5:1.0, and a male bias has been reported in live-trapping data (1.8:1.0, Crabb, 1948). Since March is the beginning of the breeding season in Florida (Mead, 1968), males were more mobile, moving an average of 800 m. compared to 430 m. for females, and so were exposed to more traps. Although the test for closure in CAPTURE was rejected, this test is confounded in the presence of behavioral response (Otis et al., 1978), invalidating this test. Because of the geography of the barrier island and the short time period involved, we are confident that we met the closure assumption. Mares and co-workers (1981) felt that adherence to the closure assumption was so critical that they chose an island (closed) population of chipmunks (Tamias striatus) in which to evaluate different population methods; they point out that statistical differences between different population estimation models might be spurious if assumptions of the model used are not met. Otis and co-workers (1978) suggested that closure might be assumed for an 8-day study of cottontails (Sylvilagus floridanus) during a nonbreeding period in a well-defined area. Thus, we feel that we have chosen the best statistical tool to model the biological situation. Since we are confident that we met the closure and tag loss assumptions, we believe our CAPTURE estimate is both accurate and precise, since the closed models used are based on fewer assumptions than open models. No. 1 1995] KINLAW ET AL.—POPULATION ESTIMATE OF SPOTTED SKUNKS 53 Our density estimate is eight times larger than Crabb’s estimate. Possible reasons for the difference may relate to the abundance of Gopherus polyphemus burrows at CNS that skunks use as breeding dens (Toland, 1991). Other factors may include the availability at CNS of abundant food combined with almost 100% vegetative cover providing protection from great horned owl (Bubo virginianus) predation (Kinlaw, 1990). Extensive areas of coastal strand with similar scrub habitat occur south of the study site on Canaveral Peninsula. If Spilogale exist at the same density on the Peninsula as our study population, then a population approaching 2000 could occur there. ACKNOWLEDGMENT—We thank James Nichols for a critical review of the manuscript. LITERATURE CITED ArNaSON, A.N. 1973. The estimation of population size, migration rates and survival in a stratified population. Res. Popul. Ecology, 15:1-8. Arnason, A.N. AND L. Baniux. 1978. POPAN-2: a data maintenance and analysis system for mark- recapture data. The Charles Babbage Research Centre, Box 370, St. Pierre, Manitoba, Canada. Caucu_ey, G. 1977. Analysis of vertebrate populations. John Wiley and Sons, New York, N.Y. 234pp. Cuapman, D.G. and C.O. JUNGE. 1956. The estimation of the size of a stratified animal population. Ann. Math. Stat. 27:375-389. Crass, W.D. 1948. The ecology and management of the prairie spotted skunk in Iowa. Ecological Monographs, 18:201-232. Enruart, L.M. 1974. Ecological studies of the spotted skunk, Spilogale putorius Gray (Carnivora) on the east coast of Florida. Trans. First Internat. Theriolog. Congress, 1:154-155. . 1976. A study of a diverse coastal ecosystem on the Atlantic coast of Florida: mammal studies. Biomedical Office, National Aeronautics and Space Administration, J.F. Kennedy Space Center, Florida. HorrMan, D.W. 1981. Canaveral National Seashore. M.S. thesis, Univ. of Florida, Gainesville, FL. 72 Bete A.H. 1906. Revision of the skunks of the genus Spilogale. North Amer. Fauna, 26:1-55. Kaplan, J.B. AND R.A. MeEap. 1991. Conservation status of the Eastern Spotted skunk. Mustelid & Viverrid Conserv. Newsletter (4):15. KINLAwW, A.E. 1990. Estimation of a spotted skunk population (Spilogale putorius) with the Jolly-Seber model and an examination of violations of model assumptions. M.S. thesis, N.C. State Univ., Raleigh, NC 202pp. Kisu, L. 1969. Survey sampling. John Wiley and Sons, New York, NY 643pp. Manaro, A.J. 1961. Observations on the behavior of the spotted skunk in Florida. Quart. J. Fla. Acad. Sci., 24:59-63. Mares, M.A., E.K. STREILEIN AND M.R. WILLIc. 1981. Experimental assessment of several population estimation techniques on an introduced population of eastern chipmunks. J. Mammal. 62(2):315- 328. McCu.toucu, C.R. AND E.K. FritzELL. 1984. Ecological observations of eastern spotted skunks on the Ozark Plateau. Trans. Missouri Acad. Sci., 18:25-32. Meab, R.A. 1968. Reproduction in eastern forms of the spotted skunk (genus Spilogale). J. Zool. 156:119-136. NicHo.s, J.D. aND K.H. PoLLock. 1983. Estimation methodology in contemporary small mammal capture-recapture studies. J. Mammal., 164:253-260. Otis, D.L., K.P. BurNHAM, G.C. WuiTE AND D.R. ANDERSON 1978. Statistical inference from capture data on closed animal populations. Wild]. Monogr. 162. 135 pp. Patton, R.F. 1974. Ecological and behavioral relationship of the skunks of Trans Pecos, Texas. Ph.D. dissert., Texas A & M Univ., College Station, TX, 199 pp. Po.tock, K.H. 1974. The assumption of equal catchability of animals in tag-recapture experiments. Ph.D. Dissert., Cornell Univ., Ithaca, N.Y. 82pp. AND M.C. Orro. 1983. Robust estimation of population size in closed animal populations from capture-recapture experiments. Biometrics 39:1035-1050. 54 FLORIDA SCIENTIST [VOL 58 Scuwartz, A. 1952. The land mammals of southern Florida and the upper Florida keys. Ph.D. dissert., Univ. of Michigan, Ann Arbor, MI 189 pp. SEBER, G.A.F. 1982. The estimation of animal abundance and related parameters. (2nd ed.) Charles Griffin & Company Ltd, London, England. 654 pp. Stout, I.J. 1979. Terrestial community analysis I. A continuation of baseline studies for environmentally monitoring space transportation systems (STS). Biomedical Office, National Aeronautics and Space Administration, J.F. Kennedy Space Center, Florida Tacua, T.C., W.D. WarDE AND K.P. Burnuam. 1982. Use and interpretation of statistics in wildlife journals. Wildl. Soc. Bull., 10:355-362. ToLaND, B. 1991. Spotted skunk use of gopher tortoise burrow for breeding. Florida Scient., 54: 10. Wuite, G.C., D.R. ANDERSON, K.P. BURNHAM AND D.L. Oris. 1982. Capture-recapture staal removal methods for sampling closed populations. Los Alamos National Laboratory, LA 8787-NERP, Los Alamos, N.M. 235pp. ZEINER, H.G. 1975. Behavior of striped and spotted skunks. Ph.D. thesis., Univ. of California, Berkeley, 150pp. Florida Scient. 58 (1): 47-54. 1995. Accepted: November 15, 1994 No. 1 1995] yD) Biological Sciences DEVELOPMENTAL RESPONSES OF ESTABLISHED RED MANGROVE, RHIZOPHORA MANGLE L., SEEDLINGS TO RELATIVE LEVELS OF PHOTOSYNTHETICALLY ACTIVE AND ULTRAVIOLET RADIATION STEPHEN M. SMITH AND SAMUEL C. SNEDAKER Division of Marine Biology and Fisheries, Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, Florida 33149-1098 Asstract: Mature, viviparous seedlings of Rhizophora mangle L. were harvested from a variety of adult trees and subsequently grown under conditions of ambient natural sunlight, UVb-filtered sunlight, and shade to determine the effects of relative levels of UVb/PAR on early root and shoot development. Growth was generally reduced with exposure to UV, with shoot elongation exhibiting the largest treatment differences among all growth indices. The results suggest that open, exposed environments are suboptimal for the early development of R. mangle upon establishment. STRATOSPHERIC ozone depletion allows increased penetration of ultraviolet b (UVb, 280 -310 nm) solar radiation to the earth’s surface, a factor that is known to _ have deleterious effects on a wide variety of organisms (Levitt, 1972). A number of physiological processes in many plant species are altered during chronic exposure to enhanced UVb (Biggs et al., 1981; Sisson, 1984; Tevini et al., 1983). The red mangrove, Rhizophora mangle L., is a halophytic woody spermatophyte common to the land-sea interface of tropical and subtropical intertidal zones that experience relatively high doses of biologically-active and DNA-responsive UVb radiation (Roach, 1992; Tevini, 1993). Although R. mangle has presumably adapted to this type of environment, its physiological response thresholds to specific quantities and qualities of light, particularly UVb, remain unclear. The Rhizophora have hitherto been described as both shade-tolerant and shade-intolerant (Macnae, 1966, 1967). However, there is some evidence to suggest that ambient light levels may well exceed optimum levels. For example, isolated R. mangle seedlings exposed to dawn to dusk solar radiation often fail to develop in spite of the fact that all other environmental factors appear favorable. Seedlings of a related species, Rhizophora apiculata L. Blume, have been reported to exhibit better growth under shade (48% relative irradiance) than in full sunlight (Kathiresan and Moorthy, 1993). Bjorkman and co-workers (1988) showed that in general mangrove leaves had low water potentials, low stomatal conductance, and low light-saturated CO2 exchange rates compared to non-mangrove species. Additionally, mangrove sun leaves were characterized by a low energy conversion efficiency (ECE) com- pared to shade leaves, indicating that mangroves may often receive light in excess of physiological requirements. Furthermore, it has been postulated that the metabolic energy requirement of maintaining salt balance may contribute to decreased resistance to high light stress, although the relationship between these two physical BG FLORIDA SCIENTIST [VOL 58 factors remains unclear (Lovelock et al., 1992). Since studies of UV radiation effects on plant growth have been largely limited to high altitude species and crop plants (National Research Council, 1983), the main objective of this research was to characterize the growth and developmental responses of the viviparous seedlings of R. mangle to UV/PAR exposure. MetHops—Thirty mature propagules (mean length = 224 mm + 4.15 SE, mean mass = 23.94 g + 0.82 SE) were harvested from several adult R. mangle trees that were part of a fringe mangrove forest located within Matheson Hammock Park, Miami, Florida. Individuals of similar size and ripeness, as indicated primarily by protrusion of the cotyledonary collar (Banus and Kolehmainen, 1975), were selected. Previously abscised propagules lying on the ground were not used in this experiment for several reasons. First, it is impossible to determine the length of time, and thus the extent of physiological development, since abscission. Secondly, abscised propagules may be affected by acute exposure to environmental factors that would not be encountered on the parent trees. Also, differences in salinity, soil chemistry, water availability, etc., of the ground-surface microhabitat may affect the onset of early development processes which appear to be strictly regulated by the parent tree during viviparous development (Pannier and Pannier, 1975). Finally, the use of ripe propagules that are still attached to the tree assures a similar starting point in terms of physiological state. The 30 propagules were divided into three light-treatment groups. Each group was then further divided in half and planted in two identical 21L plastic containers to provide adequate soil space for root growth. The treatment groups were evaluated statistically, however, as single groups of ten since both containers for each group of five were placed side by side under the same experimental conditions. A commercial mixture of perlite, silica sand, and organic matter was used as substrate. Light treatments corresponded to natural ambient sunlight (aUVb), UVb-filtered sunlight (-UVb), and shade (Sh). A single sheet of 5 mm thick clear Plexiglas erected on four corner supports served as a UVb filter without significantly reducing the transmission of photosynthetic active radiation (PAR). The shade treatment employed semi-translucent fiberglass that essentially blocked all UVb, and reduced PAR to approxi- mately 13 percent full-strength sunlight. Four identical corner supports were also set up around the aUVb treatment containers in order to mimic the shadows present in the other groups. Light intensities recorded with an International Light™ IL1700 research radiometer are presented in Table 1. Air temperatures under the filters did not differ significantly from the uncovered treatment because the filters were flat and allowed for complete air circulation through the system. Also, the experiment was conducted near the shoreline in an area which receives a constant breeze from the ocean. All plants were watered daily with 1 L of ~ 10 - seawater following the technique described by Lin and Sternberg (1992). Since the exposed containers subjected to ambient conditions received normal rainfall, equivalent quantities of collected precipitation were added to the covered containers to insure that each treatment received equal amounts of the same quality of water. Holes in the bottoms of the containers allowed for drainage to prevent waterlogging effects and a buildup of soil salinity. Seedlings were monitored over a period of approximately 6 months from September 1993 to February 1994, during which time stem length, leaf index (sum of leaf lengths), leaf number, and mean leaf lengths were recorded seven times. Root index (sum of root lengths), root number, mean root length, were recorded only twice, at 17 and 37 days, due to the difficulty of excavating plants for measurement without damage. The data were compared using Analysis of Variance followed by apriori Least Significant Difference tests. ResuLts—Root development - After 17 days of growth, the mean root index for plants grown under UVb-filtered sunlight (-UVb) was slightly higher than for unfiltered, natural sunlight (aUVb) or shade (Sh) treatments (Fig. 1). By day 37, the mean root index in the -UVb treatment was significantly higher (p < 0.1) than the aUVb treatment, but not from the Sh treatment. The aUV root index was lower, but statistically similar to the Sh value. The mean root lengths (not shown) of seedlings exhibited a similar pattern. Values in the -UVb and Sh treatments were significantly higher than in the aUVb group after 17 days of growth. After 37 days, the differences were still evident but not statistically significant. In contrast, mean numbers of roots No. 1 1995] SMITH AND SNEDAKER—DEVELOPMENTAL RESPONSES OF ESTABLISHED MANGROVES Sor Root index Time (days) Fic. 1. Mean root index over time (days) for aUVb (empty bars), -UVb (light-shaded bars), and Sh (dark- shaded bars) treatments. Lowercase “s” represents significant difference (P<0.1) between adjacent groups; uppercase “S” represents significant difference between first and last groups (aUVb vs. Sh). Stem length Time (days) 160 Fic. 2. Mean stem lengths over time (days) for aUVb (empty bars), -UVb (light-shaded bars), and Sh (dark- shaded bars) treatments. Lowercase “s” represents significant difference (P<0.1) between adjacent groups; uppercase “S” represents significant difference between first and last groups (aUVb vs. Sh). Leaf index Time (days) Fic.3. Meanleafindexovertime (days) foraUVb (emptybars), -UVb (light-shaded bars), and Sh (dark-shaded bars) treatments. Lowercase “s” represents significant difference (P<0.1) between adjacent groups; uppercase “S” represents significant difference between first and last groups (aUVb vs. Sh). 58 FLORIDA SCIENTIST [VOL 58 per seedling in the a@UVb and -UVb treatments were slightly higher than those under shade. Shoot development—tThere were well defined patterns in stem and leaf development among treatments. The mean stem length in the Sh treatment was significantly longer than the -UVb value which, in turn, was significantly higher than the aUVb value in all stages of development after 37 days of growth (Fig. 2). Mean leaf index values in the -UVb and Sh seedlings were also significantly higherin aUVb propagules in the majority of measurements taken after 51 days of growth (Fig. 3). Leaves on the propagules in shade emerged first and were noticeably greener than those in both aUVb and -UVb groups, and, the mean number of leaves per seedling (not shown) in the Sh treatment was significantly higher than the aUVb and -UVb groups in the initial stages of development. Mean leaf lengths (not shown) exhibited differences among treatments primarily during the latter stages of development; values were highest for the Sh treatment but did not differ between the aUVb and UVb- treatments. After 121 days of growth, both the -UVb and Sh groups exhibited higher leaf numbers than the group exposed to aUVb. Discussion—The early growth of R. mangle seedlings appears to be favored by either shade or the absence of UVb . Over the longer term, stem elongation showed the largest response among treatments. In this regard, accelerated height growth (ie., stem elongation) in the shade was likely a result of etiolation, a natural phenomenon in most species of vascular plants. In ambient, high-intensity sunlight, lower endogenous levels of indoleacetic acid (which can be photoxidized by UVb radiation) and/or gibberellins may account for the reductions in stem elongation (Morgan, 1990). In fact, it has previously been suggested that the short, “umbrella- shaped” tree structure observed in mangroves in fully-exposed, open areas with a long duration of daily sunshine (Macnae, 1967; Saenger and Hopkins, 1975) may be a developmental consequence of alterations in levels of endogenous growth regu- lators or, alternatively, decreased tissue sensitivity to these substances (Hutchings and Saenger, 1987). Another general effect of UVb on plant development is a decrease in the rate of leaf expansion - a process believed to be controlled by gibberellin and/or cytokinin activity (Sisson and Caldwell, 1976). In these experi- ments leaf development was similarly inhibited by exposure to unfiltered sunlight. It thus appears that the interaction of growth regulators with the light environment may be an important aspect of developmental responses in mangroves. Seedlings subjected to the aUVb treatment never exhibited the highest values for any measured aspect of growth. This suggests that the open, fully-exposed type of environment is suboptimal for the early development of R. mangle. Light require- ments may change, however, over the course of the life cycle as plant tissues become acclimated or “hardened” with age. It is also possible that these responses are No. 1 1995] SMITH AND SNEDAKER—DEVELOPMENTAL RESPONSES OF ESTABLISHED MANGROVES 59 TABLE 1. Intensities of UVa, UVb, and PAR (W/cm2) and corresponding indices relative to the natural sunlight (i-ns) treatment among aUVb, -UVb, and Sh groups (values are means of 5 replicate measurements taken on Oct 21/1993, 12:00 pm). Treatment UVa i-ns UVb i-ns PAR i-ns aUVb 3.17E-02 1.00 3.40E-04 1.00 1.61E-03 1.00 -UVb 2.95E-02 0.93 6.50E-06 0.02 1.60E-03 (0.99 Sh 8.40E-03 0.26 6.00E-07 0.00 2.00E-04 0.13 indicative of a particular genotype of seedlings originating from the same adult population. Undoubtedly, a larger number of propagules selected from a wider variety of habitats would have provided better information on the UVb/high-light inhibitory response. Of further interest is the question as to whether viviparous propagules show more rapid development within the shade of the inner canopy compared with those developing in exposed locations such as the ends of sunlit branches. Such information may shed light on the degree to which vivipary mediates external factors of the environment. Plants in the two high-light treatments received similar doses of photosyntheti- cally active radiation (see Table 1); thus, it appears that UVb was the primary factor contributing to reduced or altered development. This is significant due to the fact that ambient levels of UVb are lowest at the time of the year that the experiment was conducted. It is also pertinent to note that these experiments were conducted on Virginia Key, Florida (25° 46' N, 80° 12' W) which is near the latitudinal range limit for this species. These plants therefore received comparatively lower doses of solar radiation than those growing at lower latitudes would generally experience (Tevini, 1993). Furthermore, we speculate that increased UVb exposure as a result of stratospheric ozone depletion may ultimately influence distribution patterns and the relative abundance of this species as a result of altered development and competitive ability. ACKNOWLEDGMENTS— This research was supported in part by the U.S. Environmental Protection Agency (CR820667). We thank the anonymous reviewers for suggestions that improved the substance of paper. 60 FLORIDA SCIENTIST [VOL 58 LITERATURE CITED Banus, M.D. anp S.E. KOLEHMAINEN. 1975. Floating, rooting and growth of red mangrove (Rhizophora mangle L.) seedlings: effect on expansion of mangroves in southwestern Puerto Rico, Vol. 1, Pp. 370-384. In: WaLsH, G., S. SNEDAKER AND H. Tas (eds.) Proc. International Symp. Biology and Management of Mangroves. Institute of Food and Agricultural Sciences, Univ. Florida, Gainesville, FL. 846 pp. Biccs, R.H., S.V. KossutH, AND A.H. TERAMURA. 1981. Response of 19 cultivars of soybeans to Aitmexrtollete B irradiance. Physiol. Plant. 53:19-26. Bjorkman, O., B. DeEmMic AnD T.J. ANDREWS. 1988. Mangrove photosynthesis: response to high- fediance stress. Aust. J. Plant Physiol. 15:43-61. Hurcuincs, P. AND P. SAENGER. 1987. Ecology of Mangroves. St. Lucia, Qld., Australia, University of Onaerslend Press. 388 pp. KATHIRESAN, K. AND P. Moortuy. 1993. Influence of different irradiance on growth and shove mate characteristics in seedlings of Rhizophora species. Photosynthetica 29:1-4. Levitt, J. 1972. Radiation - visible and ultraviolet radiation, pp. 447-459. In: Responses of plants to environmental stresses. Academic Press, New York, NY. 697 pp LoveLock, C.E., B.E. CLoucu, AND I.A. Wooprow. 1992. Distribution and accumulation of ultraviolet radiation absorbing compounds in leaves of tropical mangroves. Planta 88:143-154. Lin, G. AND L. STERNBERG. 1992. Effect of growth form, salinity, nutrient and sulfide on photosynthesis, carbon isotope discrimination and growth of red mangrove (Rhizophora mangle L.) Aust. J. Plant Physiol. 19:509-517. MacnaeE, W. 1966. Mangroves in eastern and southern Australia. Aust. J. Bot. 14:67-104. . 1967. Zonation within mangroves associated with estuaries in North Queensland, pp. 432-441. In: LAUFF, G.H. (ed.) Estuaries, Amer. Assoc. Adv. Sci., Washington, D.C. Publ. 83. Morcan, P.W. 1990. Effects of abiotic stresses on plant hormone systems, pp.113-146. In: Stress responses in plants: Adaptation and acclimation mechanisms, Wiley-Liss, New York. 407 pp. NaTIONAL RESEARCH CouNCIL. 1983. Effects of UVb radiation on plants and vegetation as ecosystem components, pp. 207-249. In: Causes and effects of changes in stratospheric ozone: update 1983. Academy Press, Washington, D.C. 254 pp. PANNIER, F. AND R.F. PANNIER. 1975. Physiology of vivipary in Rhizophora mangle, Pp. 632-642. In: Watsu, G.S. SNEDAKER AND H. Teas. (eds.) Proc. International Symp. Biology and Management of Mangroves. Institute of Food and Agricultural Sciences, Univ. Florida, Gainesville, FL. 846 pp. Roacu, M. 1992. Sun struck. Health May/June p. 41. SAENGER, P. AND M.S. Hopkins. 1975. Observations on the mangroves of the south-eastern Gulf of Carpentaria, Australia, Vol. I, Pp. 126-136. In: Watsu, G.S. SNEDAKER AND H. Teas (eds.) Proc. International Symp. Biology and Management of Mangroves. Institute of Food and Agricultural Sciences, Univ. Florida, Gainesville, FL. 846 pp. Sisson, W.B. 1984. Effects of UV-B radiation on photosynthesis. In: WorrEsT, R.C. AND M.M.CALDWELL (eds.) Stratospheric ozone reduction, solar ultraviolet radiation and plant life. Vol. 8, NATO ASI Series, Series G: Ecol. Sci. 324 pp. AND M.M. CaLpweLt. 1976. Photosynthesis, dark respiration, and growth of Rumex patientia L. exposed to ultraviolet irradiance (288-315 nm) simulating a reduced atmospheric ozone column. Plant Physiol. 58:563-568. Tevini, M., U. THomas and W. Iwanzik. 1983. Effects of enhanced UV-B radiation on germination, seedling growth, leaf anatomy and pigments of some cropplants. Zeit. fur Pflanzenphy. 109:435- 448. . 1993. UV-B radiation and ozone depletion: etieetat on humans, animals, plants, micro- organisms, and materials. Lewis Publishers, London. 248 pp. Florida Scient. 58 (1): 55-60. 1995. Accepted: October 26, 1994 No. 1 1995] 61 REVIEW William B. Robertson, Jr. and Glen E. Woolfenden, Florida Bird Species: An Annotated List, Florida Ornithological Society, Special Publication No. 6, Gainesville, Florida, 1992. Pp. ix + 260. Available from: Editor, Special Publications F.O.S., Archbold Biological Station, P.O. Box 2057, Lake Placid, Florida 33852. Softcover $17.95, cloth $22.95, plus $2.00 shipping fee per book (Florida residents must add 6% sales tax on the total price of the order). TWO premier ornithologists, who shared a combined ‘total of 75 years of experience in Florida at the time of writing, have produced an information-rich annotated list of the bird species that have occurred in Florida in historical time. From common species to ephemeral exotics, Robertson and Woolfenden succinctly present capsules of evidence supporting the composition of Florida avifauna and a remarkable amount of additional material. The authors have held a high standard of record-keeping for themselves and have fostered scientific ornithology for many years through their activities in the Florida Ornithological Society. Florida Bird Species is a tribute both to the efforts of many birders in the state and the high caliber of the authors. The book is organized as follows. The Introduction outlines the criteria for inclusion in the list, what constitutes verifiable evidence, and the distinction between “records” and “reports.” Four questions are addressed in the species accounts. First, if it is rare, what is the evidence that the species has occurred in Florida? Second, where in Florida has it occurred? Third, what are the important characteristics of its occurrence? And, fourth, how, if at all, has its pattern of occurrence changed during the period of record? Species accounts, a literature cited section with approximately 500 references, an index, anda checklist of the verified species follow. The list of 671 bird species that have occurred in the wild in Florida is divided into four categories. Inclusion in the largest category, Verified Species (461 species, including 11 exotic and 4 extinct species), hinged on “the existence of archived data which anyone who chooses may examine and form an independent opinion.” The other categories are listed in appendices: Unverified Stragglers (75 species), Probably Unestablished Exotics (16 species), and Unestablished Exotics (119 species). Both scientific and common names are indexed. Putting species into categories involves difficult decisions. Foremost of these is deciding how many categories to make. The authors must have wrestled with the tendency to proliferate categories, because on page 2 they announce that they will distinguish five categories, and then proceed to name only four. They won the battle to keep it simple. In categorizing species, the authors never hesitate to acknowledge ambiguity (e.g., Scarlet Ibis, Muscovy Duck, etc.) and then let the reader decide. This conservative inclusive approach is a strength of the volume. The authors admit that Appendix A, Unverified Stragglers, is “a scrap basket for some of the more intractable problems of the Florida ornithological record.” It contains diverse species such as Peruvian Booby, King Vulture, Great Auk, Common Potoo, Eurasian Jackdaw, and Black-capped Chickadee. Some of the reports of the occurrence of 62 FLORIDA SCIENTIST [VOL 58 these species in Florida are weak at best, but the authors present the best evidence supporting their judgment to provide future researchers with a firm foundation for reassessment. Another valuable aspect of the book is its treatment of exotics. The authors cast a wide net to assemble records and reports of the remarkable diversity of species that “probably required human assistance to reach Florida.” A total of 146 species, including 63 species of parrots, are listed, of which only 11 species (e.g. Red- whiskered Bulbul) have become established. This provides valuable documentation of potential Florida bird life. The result is an impressive amount of information presented in a clear and consistent fashion. The authors established operational definitions for terms used to describe distribution, population status, seasonality, abundance, and frequency of occurrence and then adhered to those definitions. In addition to the above, the authors also add knowledge of banding recoveries (e.g., Double-crested Cormo- rant), history (e.g., Cattle Egret), and habitat (e.g., Sedge Wren) where appropriate. This book will be essential to ornithologists and birders in Florida and elsewhere. Biogeographers, ecologists, and resource managers, who want a standard reference of what birds occur in Florida will find this an extremely useful volume at a very reasonable price. —R. Todd Engstrom, Tall Timbers Research Station, Rt. 1 Box 678, Tallahassee, Florida 32312. No. 1 1995] 63 REVIEW Humphrey, Stephen R. ed., Rare and Endangered Biota of Florida: Vol. 1, Mammals, University Press of Florida, Gainesville. 1992. Pp. vi + 392. THIS book is part of the series describing the rare and endangered plants and animals of Florida. The series was initiated by the Florida Committee on Rare and Endangered Plants and Animals (FCREPA), an organization of scientists, conserva- tionists, and citizens founded in 1973. The effort to update each of the volumes in the series has been the a cooperative endeavor of many scientists in the public and private sectors, and the work has been supported in part by the Florida Game and Fresh Water Fish Commission, Florida Power and Light Co., and the Save the Manatee Club. Ray Ashton, Jr. of Water and Air Research, Inc. is the editor of the series. This book is the second edition of the original volume published in 1978 and reprinted several times since then. The material included in the 1992 version has been substantially expanded and brought up to date, and an excellent list of references appears at the end of each chapter. A total of 54 species are treated in the new volume, and well-researched information is presented concerning all of the important aspects of each species’ taxonomy, morphology, population trends, habitat requirements, distribution and range, and vulnerability. In addition, a description of conservation measures already implemented and those which have been proposed is provided, giving the reader a perspective on the best thinking in the state for species preservation. The large amount of data, the thorough explanations of the causes of vulnerability, and the chapter references make the book a compendium of essential data on the 54 species covered. Several format and material improvements over the first edition are present in this edition. Range maps are printed at a larger size which are considerably easier to read, particularly in the case of species having very limited range in the state. Also, the book is available in a standard sized, hard cover version which will withstand years of use better than did the oversize 1978 soft cover. Photographs are more numerous, although not always of the best quality. A very helpful index, not present in the first edition, is also included. As in the case of the first edition, no biologist involved in work relating to Florida’s ecology or environment will want to be without this volume and all other volumes in this series. The libraries of all academic institutions, resource manage- ment agencies, environmental consulting firms, conservation organizations, and utility companies will also benefit by having the entire series.—Patricia M. Dooris, Saint Leo College, Saint Leo, FL 33574. | 64 FLORIDA SCIENTIST [VOL 58 REVIEW George Freedman and Deborah A. Freedman, Technical Editor's Handbook: A Desk Guide for All Processors of Scientific or Engineering Copy, Dover Publications, Inc., New York, 1994 (unabridged republication of 1984 edition of The Technical Editor's & Secretary’s Desk Guide). 592 pp. $14.95 A DecabDE can be along time, especially the last one in publishing. Ten years ago, we used a typewriter exclusively, and now we use it with reluctance. How valuable is a book that is unabridged after the past decade? The authors respond with remarkable candor in a useful introduction that the book is inevitably diminished “somewhat.” They are correct, but there is much that is useful here for editors and would-be editors. The life of editors is inevitably better when authors function as would-be editors and do more of our job for us. There is much that is useful to all who would publish. The book is flawed, not for what it contains, but what it lacks. The reference to the “automated office” was prophetic, but is now with us in different levels of desktop publishing. This volume is well organized into subject areas of Mathematics, Chemistry, Biology, etc. It is concerned with the useful mechanics: proper spelling, proper usage,symbols, what to do when the right symbols don’t come forth from your favorite word processor, how to organize data, how to make editors happier, how to get published more easily. It comes with a “Dictionary of Technical Terms” and 18 useful glossaries. 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Please include Florida sales tax if shipped toa Florida address, unless a‘copy of a valid Florida Consumer’s Sales Tax Certificate is enclosed. The Florida Academy of Sciences, Inc. NON-PROFIT P.O. Box 033012 ORGANIZATION Indialantic, Florida 32903-0012 U.S. Postage PAID Permit #26 Melbourne, FL seen snes ISSN: 0098-4590 Florida ocientist in Volume 58 Special Publication ber 2 SYMPOSIUM ON HUMAN IMPACTS ON THE ENVIRONMENT OF TAMPA BAY CONTENTS NN PRMA INRA IN EN NRE eee onc ge oc sacs casens ences noescocesvececurasisvsvicesnsdondesveresdatsnboeveceescassoudeossse R. Del Delumyea 65 Review of Historical Tampa Bay Water Quality Data ..0..... eee eeeseeeeeneeee E. Howard Rutherford, Brian J. Bendis, Gabriel A. Vargo and Kent A. Fanning 67 Vegetation Changes at a Sarasota Bay Tidal Creek Restoration Project................00 G.A. Blanchard and R. Williamson 82 Tampa Interstate Study, Hillsborough County: Impacts on Historic Resources ................ J.M. Weant 82 The Continued Use of Copper Sulfate Pentahydrate in the Hillsborough River Reservoir................. Jacqueline C. Hohman and Dean F. Martin 83 Preliminary Results and Analysis of Monitoring of Ambient Water Quality and Runoff to Nearshore (EDEN TT LE TTISLLTS COTY esa eee cnr oa a Ro re nes oe ep Donald D. Moores 92 A Map of Elemental Carbon Concentration of the Air around Tampa Bay, Florida, 1990 - 1991 Jon Leonard and R. Del Delumyea 101 Human Impact on the Shark Nursery Grounds of Tampa Bay. ............. C.A. Manire and R. E. Heuter 107 Interagency Data Sharing through GIS for Cockroach Bay .............eceeeeeeeeeeeeee Charles M. Courtney 108 Modeling Light Available to Seagrasses in Tampa Bay, Florida...... R.L. Miller and B.F. McPherson 116 Resource-Based Water Quality Requirements in Tampa Bay ................:ccsccseseeees Holly S. Greening and Richard Eckenrod 116 Watershed Management in Tampa Bay: A Progress Report .............ceeeeeseeeeeeneeeee Holly S. Greening and Richard Eckenrod 117 The Age Structure of Southwest Florida’s Population ............. tec eseesecereeeeeeees William M. Spikowski 123 Regional Wildlife Planning in the Tampa Bay Region ...............ceeceeesseeeeeeeeneee James W. Beever III 130 Diurnal Dissolved Oxygen in Two Tampa Bay Seagrass Meadows: Ramifications for the Survival of Adult Bay Scallops (Argopecten irradians concentricus).............. Jay R. Leverone 141 Recent Work on Anthropogenic Impacts to Freshwater Inflows to Tampa Bay, Florida..................... Hans Zarbock, David Wade and Anthony Janicki 153 0-18 Composition of Various Water Types in the Hydrological Cycle of West-Central Florida ......... T. Netratanawong and W.M. Sackett 155 Sediment Toxicity in Tampa Bay: Incidence, Severity, and Spatial Distribution .... Edward R. Long, R. Scott Carr, Glen B. Thursby and Douglas A. Wolfe 163 Long-Term Trends of Macroalgae in Hillsborough Bay .............ccccccssscssssotesseeesseees Bridget O. Kelly 179 Evaluation and Management of Propeller Damage to Seagrass Beds in Tampa Bay, Florida ............ Peter A. Clark 193 Recovery of Water Quality and Submerged Seagrass in Tampa Bay, Florida: Se ALPEN BE ROME LOM CONSIGETALONS ..:.02)-1.5.cevesceoecever