1983 - 1985 
Ehrhardt, N. M. (1985) Cooperative stone crab research program Everglades National Park. 
Final Rep. University of Miami (RSMAS) to US Fish and Wildlife Service and South Florida 
Research Center, Everglades National Park, Homestead, FL. 55 pp. 
[NO COPY OF PAPER AVAILABLE. ABSTRACT FROM SCHMIDT (1991).] Several surveys 
conducted to assess the amount and spatial distribution of stone crabs traps fished in 
Park waters showed that during the period of this study, fishing for stone crabs was 
substantially reduced from past trends and that most fishing operations were 
restricted to an area along the coast of Cape Sable, and to a lesser extent on the 
southeast boundary of the park, along the Florida Keys. The sampling design used in this 
study assessed the stone crabs stocks exploited off Cape Sable and abundance estimates 
were obtained by direct censuses mostly through diving and by tagging. An analysis of 
the temporal-spatial location of increased stock abundance demonstrated that fishing 
operations were closely associated with areas of maximum crab abundance. Standing 
stock abundances in the study area ranged from 200,000 to 1,333,000 individuals 
based on diver surveys. Population size estimates based on tagging experiments 
indicated that an average of 35,071 males were in the study area during October 1984 
and that this population level declined to 15,211 males through February 1985 as a 
result of fishing exploitation. Based on catchability coefficients, instantaneous 
mortality rates, it was concluded that the exploitation rate observed (0.50) during the 
1984/85 fishing season in the Cape Sable area was 88.8% of that required to fully 
exploit the stock. Without a closed season a severe overexploitation of this resource 
would occur. 
1983 - 1985 
Scott, G. P., M. R. Dewey, L. J. Hansen, R. E. Owen, and E. S. Rutherford (1989) How many 
mullet are there in Florida Bay? Symp. on Florida Bay: A Subtropical Lagoon. Miami, FL. 
June, 1987. Bull. Mar. Sci. . 44(1 ):89-107. 
A fishery independent sampling survey design was implemented in Florida Bay to 
estimate the monthly biomass of mullet (Mugil spp.) in the area during 1983 - 1985. 
The method was an application of aerial visual sampling, photogrammetric sampling, 
and shipboard sea-truth sampling. Aerial visual sampling was used to estimate the 
density (D M ) and number of "muds' in the study area. Photogrammetric sampling was 
used to estimate mud surface area, and shipboard sampling was used to estimate the 
proportion of muds containing mullet and the biomass of mullet per unit area of mud (b). 
Total biomass was estimated as the product of these four variables. The method applied 
proved to be appropriate for silver mullet. Biomass of silver mullet estimates were 
found to be characterized by a high degree of variation (CV = 35%), owing primarily to 
variability of estimates of b and D M . Mud density estimates were found to be a 
relatively precise (CV = 20%) index of presumed mullet abundance based on comparison 
with fishery data. Bias was estimated to result in underestimation of mullet biomass on 
the order of a factor of 9.6 to more than 19.0. The major source of bias was due to 
estimates of b. Estimated monthly harvest of silver mullet in April-December 1984 
ranged from 2.4 to 12.0% of the bias-adjusted estimates of biomass. 
1983 - 1985 
Loftus, W. F. (1987) Possible establishment of the Mayan cichlid, Cichlasoma urophthalmus 
(Gunther) (Pisces: Cichlidae), Everglades National Park, Florida. Fla. Sci. . 50( 1): 1 -6. 
The first United States collections of the Mayan cichlid (Cichlasoma urophthalmus), a 
native of Central America, were made in January 1983 in Everglades National Park. 
The estuarine sampling site was Snook Creek, which empties into Joe Bay, 
northeastern Florida Bay. Subsequent surveys have shown that its distribution is 
limited to two areas in the Taylor Slough drainage basin. Several dozen specimens, both 
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