1990 - 1991 
Schirripa, M. J., and C. P. Goodyear (1994) Simulation modeling of conservation standards 
for spotted seatrout (Cynoscion nebulosus) in Everglades National Park. Bull. Mar. Sci. . 
54(3): 1019-35. 
A stock assessment was conducted on the spotted seatrout (Cynoscion nebulosus) stock 
of Florida Bay including simulated outcomes of six possible regulatory options. Female 
ovarian weight (g) was regressed on total length (in) (ovarian weight = 9.62E x 10' 4 
total length 3 - 542661 ; r = 0.78). Annual estimates of fishing mortality (F) for fully 
recruited fish (age 4-8) ranged from F = 0.28 in 1981 to F = 0.91 in 1974 with an 
overall average of F = 0.54. Annual estimates of spawning potential ratio ranged from a 
low of 28% in 1974 to a high of 35% in 1981. Yield-per-recruit analysis suggests that 
with 10% release mortality the fishery is now operating very near the level of 
mortality that would produce the maximum yield-per-recruit. However, a 25% release 
mortality would place the fishery beyond this level. Simulations indicate that if fishing 
mortality continues at the estimated levels for 1990 then increasing the minimum size 
to 16 in. would increase yield per-recruit by 15% and increase the spawning potential 
ratio to 40% within 5 yrs. Spotted seatrout gonad samples were collected from 
Flamingo and West Lake in 1990 and 1991. 
1990 - 1991 
Thayer, G. W., P. L. Murphy, and M. W. LaCroix (1994) Responses of plant communities in 
western Florida Bay to the die-off of seagrasses. Bull. Mar. Sci. . 54(3):718-26. 
Seagrass habitats in western Florida Bay have been undergoing changes from monotypic 
Thalassia testudinum meadows to large landscapes of barren bottoms or to increasingly 
heterogeneous Thalassia meadows as a result of seagrass die-off patch formation. The 
cause of die-off is unknown but current hypotheses point to environmental stress 
making this seagrass susceptible to disease. The potential exists for colonization and 
recovery of these die-off patches but the sequence of events and the persistence of the 
recovery have not been evaluated. Based on an existing model that represents 
theoretical successional steps toward the Thalassia climax, four habitat types were 
sampled in each of two basins of western Florida Bay. Data demonstrated a high 
potential for recovery of the denuded die-off patches. The alga Batophora oerstedii is 
the first colonizer with replacement by other algal species and subsequently Halodule 
wrightii and eventually Thalassia. Under the existing conditions of high resuspended 
carbonate sediment and biological turbidity, which are thought to be secondary 
responses of the system to the die-off of seagrasses, persistence of the colonizing 
habitats and the climax community itself is tenuous. Decreases in both Halodule and 
Thalassia in non-dieoff areas of Johnson Key Basin between spring and fall 1991 
occurred as did decreases in densities of these species in recovering patches. 
Subsequent visits in 1993 revealed that the sample sites were devoid of seagrasses. 
Plant densities were determined in Johnson Key Basin and Rabbit Key Basin during 1990 
and 1991. 
1990 - 1992 
Sheridan, P. F. (1994) Community response to seagrass die-off in Florida Bay I. Shallow 
banks. Bull. Mar. Sci. . 54(3):1083. 
Drop sampling in 1990 - 1992 compared fishes and decapods in healthy Thalassia, open 
water caused by die-off, and algal and Halodule regrowth. In waters <1 m depth, fishes 
were dominated by Lucania in Thalassia and by Floridichthys elsewhere. Decapods were 
dominated by Thor in Thalassia and by a mixture of Thor, Penaeus and Pagurus 
elsewhere. Fish and decapod densities were usually highest in Thalassia, lowest in open 
water, and intermediate in Halodule and algae. Fish and decapod species diversities 
were usually higher in disturbed habitats. These distributions may be affected by 
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