1979 - 1980 
Lutz, P. L., and A. C. Dunbar-Cooper (1984) Nest environment of the American crocodile, 
Crocodylus acutus. Copeia . 1984( 1): 153-61. 
In the southern tip of the Everglades, Florida, a small population of the American 
crocodile, Crocodylus acutus builds nests in two quite different substrates, sand/shell 
and marl. Changes in temperature, soil, water and gaseous composition were monitored 
in selected nests throughout incubation, and the gaseous resistance of the soils 
measured. Temperatures increased from approximately 30°C to a maximum of 34°C 
over incubation and no differences were found between the two nest types. The marl 
nests had a higher water content than the sand/shell nests and had a significantly 
higher resistance to gaseous diffusion. In both nest types there was a decline in P0 2 and 
an increase in PC0 2 over incubation, with greater extremes reached in the marl nests. 
In sand/shell nests, eggs lost 15% of initial wet weight over incubation. It is suggested 
that the crocodile embryo adapts to the characteristics of the different substrates by 
matching its metabolic rate to the gaseous environment of the nest. Important 
similarities in bird and crocodilian egg development suggest that the birds have been 
highly conservative in this feature of their biology. 
1979 - 1980 
Schmidt, T. W. (1993) Community characteristics of dominant forage fishes and decapods 
in the Whitewater Bay/Shark River estuary, Everglades National Park, Florida. Rep. 
NPS/SEREVER/NRTR-93/12. South Florida Research Center, Everglades National Park, 
Homestead, FL. 67 pp. 
This report presents the results of studies on the community characteristics (relative 
abundance, seasonal occurrence, size, reproductive activity, and food habitats) of the 
following dominant epibenthic forage fish and decapod crustacean species: pink shrimp 
(Penaeus duorarum), blue crab (Callinectes sapidus), pinfish (Lagodon rhomboides), 
silver jenny (Eucinostomus gula), pigfish (Orthopristis chrysoptera), and silver perch 
(Bairdiella chrysura). Juveniles and adults were collected with trawl and gill nets from 
five sites among open water bay habitats in the Whitewater Bay-Shark River system, 
March 1979 through May 1980. Macrobenthos sampling was usually conducted at each 
site on the day fish collections were made. Silver jenny, silver perch, and blue crab 
were classified as residents in the estuary while pink shrimp, pinfish, and pigfish were 
seasonal visitors which spawn offshore. Juvenile pink shrimp, the most abundant 
animal studied, occurred year-around, most abundantly during summer, fall, and 
winter, while pigfish showed abundance maxima in spring/summer. Blue crab and silver 
perch occurred most often in winter-spring while nearly equal numbers of silver jenny 
and pinfish occurred year-around. All species, except for silver jenny, occurred in 
greatest numbers at the Clearwater Pass site in mid-Whitewater Bay. This site, 
reflecting potential food sources for these species, had: (1) the greatest macrobenthic 
diversity, and abundance maximas of crustaceans (amphipoda), polychaetes, and 
mollusks (bivalves), and (2) the most dense vegetative cover of all sites sampled. 
Spatial and temporal variations in abundance of the dominant epibenthic species were 
explained, in part, by spatial and temporal patterns of food availability and habitat 
quality (i.e. sediment, vegetative cover). Salinity and temperature may only be 
autocorrelates with spawning activities and recruitment, and were not shown to be 
important limiting factors for these species. In this study, catches of small juveniles of 
pink shrimp and pigfish suggests post-larval settlement at Clearwater Pass, whereas 
catches of young silver jenny and pinfish indicates post-larval settlement in eastern 
Whitewater Bay for these species. Except for blue crab, catches of larger specimens of 
all species studied occurred at the deep water, high salinity Oyster Bay site. Diets of 
seasonal visitors (pink shrimp, pinfish and pigfish) suggested omnivory, with feeding 
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