territoriality exhibited by bald eagles toward ospreys, and quantifies the effect of this 
behavior on osprey nesting success and nest-site selection. This study took place from 
1968 to 1974 in Florida Bay. 
1968 - 1975 
Ogden, J. C. (1978) Status and nesting biology of the American crocodile, Crocodylus 
acutus, (Reptilia, Crocodilidae) in Florida. J. HerpetoL 12(2):183-96. 
This project was designed to determine the status of the American Crocodile in Florida 
and the factors regulating that population. Estimates of the historical and present range 
show that the nesting range has been considerably reduced during the 20th Century, 
including continued reduction in Florida Bay since that region became a part of 
Everglades National Park in 1950. Crocodiles in Florida Bay and on Key Largo are mound 
nesters, utilizing well-drained beaches, creek banks and abandoned canal levees as 
nesting sites. Females usually maintain primary and secondary mounds that are 
repeatedly used through many years. Average clutch size is 44; about 48% of the eggs 
hatch in successful nests, while the annual average number of successful nests is 65%. 
Most nesting failures are due to raccoon predation or failure of eggs to hatch, the latter 
probably a temperature problem in certain types of nests. The total number of 
crocodiles in south Florida early in the 20th century may have been between 1,000 and 
2,000 animals, but that total has steadily declined to the present. Based on an 
estimated 20 breeding females per year and an average 275 hatchling crocodiles 
produced annually, the 1970s population is estimated to be between 100 and 400 
animals. Factors that regulate the population, including low nesting success, human 
disturbance, and hurricanes, are discussed. 
1968 - 1984 
Fleming, D. M., N. C. Kline, and W. B. Robertson (1989) A comparison of osprey nesting 
distribution, abundance and success in Florida Bay from 1968 to 1984. Symp. on Florida 
Bay: A Subtropical Lagoon. Miami, FL. June, 1987. Bull. Mar. Sci. . 44(1):517. 
[ABSTRACT ONLY.] Declines in the Florida Bay osprey population have been documented. 
A 58% decrease in the number of nesting ospreys (Pandion halliaetus) occurred from 
1970 to 1980. This decrease was believed related to reduced productivity caused by 
lower food supplies. Objectives of this study were to: (1) assess the current status and 
trend of nesting ospreys in Florida Bay, (2) analyze the spatial distribution of osprey 
productivity throughout the Bay in relation to selected environmental factors; (3) 
examine possible hypotheses concerning the Bay osprey population decline, and (4) 
evaluate osprey population status and trend as indicators of habitat change in the Bay. 
Current osprey nesting distribution, abundance and success were compared to that 
reported in previous studies. The spatial distribution of osprey productivity throughout 
the Bay was investigated by factor and discriminate analyses of environmental 
variables. Although the number of nesting ospreys remained relatively low and 
productivity was variable, the population appeared to have stabilized in recent years. 
Osprey productivity occurred primarily on islands adjacent to the mainland coastline of 
northern Florida Bay. Within this region, areas with islands of high osprey productivity 
were characterized by high relative abundances of fish prey species in close proximity 
to bank and/or shallow water habitats, and relatively low occurrences of mammalian 
predators (i.e., raccoons). An apparent relationship was also noted between annual 
rainfall and salinity variability, the relative abundance of important fish prey species, 
and subsequent osprey productivity. No such relationship appears to exist with the 
number of breeding pairs. Excluding the adverse effects of unseasonal weather events, 
osprey productivity appears to be a good indicator of macrohabitat changes that may 
occur in Florida Bay each year as a result of annual stochastic environmental 
variability. However, the usefulness of osprey population trends as an indicator of long 
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