Variation of C, N, and P content of leaves of Thalassia testudinum was measured on two 
spatial scales: locally (10-100 m) in relation to a point source of nutrients associated 
with a bird colony in eastern Florida Bay, and regionally (10-100 km) across all of the 
Florida Bay. Locally, the P content of leaves decreased from a high of 0.16% P (wt/wt) 
30 m from the nutrient source to a low of 0.08% 120 m from the source; the C and N 
content (34.9 and 2.19%) was independent of distance from the nutrient source. Due to 
variations in P content, C:P and N:P, but not C:N, varied locally. Regionally, P content 
varied greatly, from 0.05 to 0.209%. Carbon (29.4 - 39.5%) and N (1.7 - 2.7%) 
showed considerably less variation. Variation in C:P and N:P across the Bay 
encompassed a range nearly as great as reported for all seagrasses around the world 
combined. The C:N ratio showed little variation. Local variation around the nutrient 
point source indicated that C:P and N:P were indicators of P availability, and trend 
analysis of the regional spatial variation in C:P and N:P showed that P availability was 
greatest in northwest, and least in eastern Florida Bay. This pattern mirrored 
abundance of seagrasses and productivity in the Bay. T. testudinum from the Bay 
appears to be P limited and N saturated, even in the sparsest seagrass communities. 
This study was carried out from 1987 to 1989. 
1987 - 1989 
Strong, A. M., R. J. Sawicki, and G. T. Bancroft (1991) Effects of predator presence on the 
nesting distribution of white crowned pigeons in Florida Bay. Wilson Bull. . 103(3):415-25. 
From 1987-1989, surveys were conducted throughout Florida Bay, Card and Barnes 
Sounds, the southern portion of mainland Florida, and the mainline Keys south to Long 
Key to determine the breeding distribution of white-crowned pigeons ( Columba 
leucocephala). We found pigeons nesting on 88 of 169 keys over a wide range in Florida 
Bay, Card and Barnes Sounds, and in one location in the mainline Keys. Their nesting 
distribution appeared to be limited by the presence of raccoons ( Procyon lotor). Of the 
33 keys on which we found evidence of raccoons, only six had nesting white-crowned 
pigeons. Other potential nest predators did not seem to influence nesting distribution. In 
Florida, white-crowned pigeon breeding populations apparently are limited by the 
availability of nesting sites without raccoons. 
1987 - 1990 
Robblee, M. B., T. R. Barber, P. R. Carlson, M. J. Durako, J. W. Fourqurean, L. K. 
Muehlstein, D. Porter, L. A. Yarbro, R. T. Zieman, and J. C. Zieman (1991) Mass mortality 
of the tropical seagrass Thalassia testudinum in Florida bay (USA). Mar. Ecol. Prog. Ser. . 
71:297-9. 
This report documents the rapid and widespread mortality of the seagrass Thalassia 
testudinum Banks ex Konig (turtlegrass) in Florida Bay. More than 4,000 ha of seagrass 
beds have been completely lost in recurring episodes of mortality since the summer 
1987. An additional 23,000 ha have been affected to a lesser degree. Loss of T. 
testudinum, the dominant macrophyte species in this highly productive system, may 
affect the ecosystem function within the Bay as well as estuarine-dependent sport and 
commercial fisheries. A pathogenic protist related to the causal agent of the eelgrass 
wasting disease may be involved in the mortality and may place T. testudinum 
populations outside Florida Bay at risk. Environmental factors and chronic hypoxia of 
below-ground T. testudinum tissue may also contribute to the die-off. Blade density 
data of test beds in Johnson Key Basin collected from June 1988 to March 1990 are 
presented in the paper. 
1988 0 
Knight, C. D. (1988) Mechanical compaction of Recent carbonate sediments in Florida Bay. 
The Compass . 65(2): 111-15. 
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