fishing intensity. Descriptions of some of the major fish and shellfish are 

 given in the following sections. 



FINFISH 



Ordinarily, seafood is divided into finfish (referred to as fish here- 

 after in this report) and shellfish (e.g., oysters, shrimps, crabs). In 

 addition to their commercial value, finfish support a highly valued sport 

 fishery. 



Snappers and Groupers 



Seven species of snappers are taken in the Florida fishery. Red snapper 

 is the most valuable and makes up most of the catch. Red snapper landings in 

 Southwest Florida averaged about 995,000 lb annually in 1970-80 (about 25% of 

 the statewide red snapper landings). 



Commercial landings of groupers in Southwest Florida have been relatively 

 stable, averaging a little over 5 million pounds annually since 1965. Monthly 

 catches also are relatively stable except for slight declines in January and 

 February. The landed value in 1980 was just under $1.00 a pound. 



Relatively little is known about the early life history of snappers and 

 groupers. Only a few of the larvae among the snapper species have been 

 described and specific areas of spawning are unknown. Most fish probably 

 spawn in deeper coastal waters in spring, summer, and fall and the pelagic 

 larvae are transported by prevailing currents to shallow coastal waters and 

 estuaries which are used as nursery grounds (Beaumariage and Bullock 1977). 

 As juveniles they move from shallow reefs or grassy areas to deeper holes or 

 hard bottom outcroppings. Adults seldom stray far from hard rock outcrop- 

 pings, reefs, or corals because of their need for cover in protective holes 

 and crevices. The size and growth rates of each species of grouper varies. 



Although the biological characteristics of each species of grouper may 

 vary, the gag ( Mycteroperca micro! epis ) has been studied the most. This 

 species in its second year of life is about 14 inches long and weighs between 

 2 and 3 lb. Most of the largest groupers landed commercially are 5 or 6 years 

 old and average 20 to 25 lb. Maximum age is about 30 years. Sexual maturity 

 is reached in 2 to 4 years, and most groupers are protogynous hermaphrodites 

 which begin life as females. Transformation to males begins at about age six, 

 but not all become males. Factors causing sexual change are not understood, 

 but the purpose probably is to prevent the loss of males from the highly 

 territorial populations found in the relatively isolated reef areas. 



Red snappers are long lived (up to 20 years), slow growing, deep reef 

 dwellers (Futch and Bruger 1977). They are essentially non-migratory except 

 for seasonal inshore-offshore movement. They eat shrimp, crabs, other crusta- 

 ceans, and fish. 



The increasing competition for snappers and groupers by commercial and 

 sport fishermen in Florida may be reducing the abundance of these species to 

 relatively low levels. The closing of Mexican fishing grounds to Southwest 

 Florida fishing fleets has diverted even more fishing pressure toward the 



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