organic material between the near shore shallow-water environment and the coastal 
shelf zone. In the fall of 1979, surface drift material was collected from 42 stations 
encompassing 14000 km 2 west of Florida Bay. Two seagrasses, Thalassia testudinum 
and Syringodium filiforme, accounted for 90% of the drift material. Surface drift 
averaged 9.4 g dry weight m' 2 adjacent to the source seagrass beds, and decreased 
with distance from these beds. The total standing stock of drift material in the study 
area was 5000 metric tons dry weight. Samples from smaller studies in 1978 and 
1980 show that the transport of material is highly variable. The exchange of material 
between the inshore grass beds and to coastal shelf region is governed largely by wind 
speed and direction, with the majority of material being transported westward from 
Florida Bay and the lower Keys. A turnover time of approximately 20 days is estimated 
for the floating seagrasses, which could represent an annual input of 7.2 g nr 2 to the 
offshore sediments using the 1979 data. 
1982, 1985 - 1987 
Brasier, M. D., and O. R. Green (1993) Winners and losers: stable isotopes and 
microhabitats of living Archaiadae and Eocene Nummulites (larger forminifera). Mar. 
Micropaleontol. . 20(3-4):267-76. 
This paper discusses isotopes in larger foraminiferal calcite from two contrasting 
settings: modern Florida Bay, dominated by Archaiadae (the "winners'); and the Upper 
Eocene Banon Clay of England, locally dominated by Nummulites ("the losers"). The 
archaiads (plus peneroplids and soritids) were mainly collected from Thalassia leaves. 
They yield signatures that closely reflect strong isotopic gradients in seawater across 
Florida Bay and the outer patch reefs. Isotopic signatures of eurytopic Androsina lucasi 
record extreme conditions to the north of the Bay, which includes 5 13 C evidence for 
much nutrient-regeneration. Such tolerance of relatively eutrophic conditions may 
explain the capacity of Archaiadae for survival in the Caribbean region during the 
Neogene. Isotopes of Nummuliles prestwichianus from the basal Bartonian compare 
more closely with data from living nummulite Heterostegina. 8 18 0 indicates a yearly 
growth cycle under tropical bottom water temperatures with an annual range of 
approximately 2.5°C. Carbon isotopes show a trend towards heavier values with 
growth, here related to decelerating rates of calcification and, perhaps, the additional 
effects of test-thickening on carbon isotope fractionation by endosymbionts. The 
nummulitic data indicate a much more stable carbon and nutrient cycle in the basal 
Barton Clay than seen in the Florida Bay mud mound assemblage. This is consistent with 
their presumed stenotopic and oligotrophic life habit. It could well explain their 
vulnerability to extinction after the mid-Eocene, and the post-Aquitanian decline of 
larger rotaliids and reefs in the Caribbean region. Sampling took placed August to 
September during 1982, and 1985 to 1987 at various locations in Florida Bay. 
1982 - 1984 
Wilson, K. A. (1989) Ecology of mangrove crabs: predation, physical factors and refuges. 
Symp. on Florida Bay: A Subtropical Lagoon. Miami, FL. June, 1987. Bull. Mar. Sci. . 
44( 1 ):263-73. 
The relative importance and interactions of biological and physical factors as influences 
on microhabitat utilization of crabs in mangrove forests in Florida Bay was examined. 
Two experimental approaches were taken: (1) Estimation of the relative risk of 
predation among microhabitats in the mangrove on a tidal, seasonal, and annual basis; 
and (2) Measurement of responses of crabs to exposure in microhabitats in the field. 
Florida Bay mangroves are intertidal soft-sediment habitats in which four species of 
mangrove crabs broadly overlap in habitat utilization and share periodic shifts in 
microhabitat selection. Aratus pisonii is an arboreal crab; Eurytium limosum, Sesarma 
curacaoense, and Uca thayeri live in burrows and holes on the mud surface and 
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