contents. Six hundred and thirty-six, or 48%, contained food. Crustacea, 
predominantly amphipods and palaemonid shrimp, are the main food (93% of mean food 
volume) of juvenile snapper from grass beds. Slightly larger snapper from around 
brush and debris in grass beds had 69.4% Crustacea; chiefly Penaeus duorarum, 
xanthid crabs and pertunid crabs. Fish made up 29.1% of food volume and Opsanus beta 
was the commonest fish. Snapper (largely adults) from an inshore channel contained 
59.5% Crustacea (mainly Portunus sp.) and 36.5% fish ( Opsanus beta again the 
commonest). Crustacea were chiefly shrimp and portunid crabs. Copepods, amphipods, 
palaemonid shrimp, penaeid shrimp and portunid crabs successively dominate the 
Crustacea eaten by gray snapper as they increase in size. Fish assume an increasing 
role in the diet of large snapper. Most food items are swallowed whole and most range 
in size from eight to 45% of SL though elongate forms such as eels may be eaten even if 
longer than the snapper. Juvenile gray snapper from grass beds feed in the day while 
larger snapper are nocturnal feeders. Stomachs examined in later afternoon were 
almost entirely empty. Schools of gray snapper break up at dusk and disperse into 
surrounding areas to feed. Large gray snapper may range a mile or more at night from 
points of diurnal concentration. The feeding habits of gray snapper are not highly 
selective and are more generalized than those of the other species of snapper. The 
over-all sex ratio of gray snapper is about equal though mature females predominate in 
shore channels and males on the reef. The smallest mature female was 195 mm SL and 
the smallest mature male was 185 mm SL among 722 specimens examined. No 
significant difference in size of sexes was noted though the four largest fish (430 to 
489 mm) were females. Ripe females were common in July and August and spent 
females common in early September. Spawning occurs more than once and probably 
around the time of full moon. The occurrence of small juveniles indicates some 
spawning as early as June. A 315 mm female gray snapper was estimated to have 
about one half million eggs. Schooling behavior is strongest in adult fish and is greatest 
in areas of reduced cover. Schools of mixed species including gray snapper are 
common. Small snapper from inshore areas show no directed seasonal movements other 
than being driven from certain exposed locations by low temperatures or storms. Adult 
gray snapper migrate to the offshore reefs to spawn in summer. A much smaller 
population of gray snapper are year-round residents of the reefs. Tagged snapper 
moved as much as 40.5 nautical miles in seven days following the fall break-up of the 
summer schools at Alligator Reef. Gray snapper occasionally submit to removal of 
ectoparasites by other fishes. The latter include the neon goby (Elacantinus oceanops). 
Spanish hogfish (Bodianus rufus) and juvenile porkfish (Anisotremus virginicus). The 
wide geographic and ecologic range of L. griseus is attributed to its generalized nature. 
Restrictive measures for the protection of this species are not needed at present or in 
the immediate future. Adult populations of gray snapper could probably be substantially 
increased by proper placement of manmade cover. 
1964, 1966 - 1967 
Smith, W. G. (1968) Sedimentary environments and environmental change in the 
peat-forming area of south Florida. Ph. D. Dissertation. Pennsylvania State University, 
University Park, PA. 254 pp. 
The kinds of sediments which occurred in 48 cores which are within or marginal to peat 
forming areas in South Florida were described. These were subdivided into various 
types based on ash content, kinds of mineral matter, floral elements, faunal elements, 
color, texture, and other properties. Comparisons of sulfur content elements from 
freshwater areas and areas of marine influence were also made. Observations on 
surface environments and plant communities presently existing in the area were used 
to relate these sediment types environments of accumulation. The sequences of 
sediments were described and relate to historical development of the area in the last 
thousand years. All of this information was used to make inferences about the 
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