OCCURRENCE IN TAMPA BAY, FLORIDA, OF IMMATURE SPECIES 

 DOMINANT IN GULF OF MEXICO COMMERCIAL FISHERIES 1 



By James E. Sykes, Fishery Biologist (Research Administration), and John H. Finucane, Fishery 

 Biologist (Research), Bureau of Commercial Fisheries 



ABSTRACT 



Populations of finfish, crabs, and shrimp were sam- 

 pled from August 1961 through November 1962 as part 

 of Tampa Bay estuarine studies. Specimens collected 

 were identified to species and classified as immature or 

 adult. Twenty-three species of major importance in 

 Gulf of Mexico commercial fisheries were found to 

 inhabit Tampa Bay during immaturity. Seasonal and 

 areal distribution is described for the species common to 

 Tampa Bay biological collections and catches in the 

 Gulf. Although most of these species were distributed 



throughout the Bay system, Old Tampa Bay harbored 

 greater numbers of them than any other area. Hills- 

 borough Bay, an area of the system similar to Old 

 Tampa Bay in salinity regimen, harbored fewer impor- 

 tant species than any other area. Its relatively low 

 production is attributed to loss of the natural habitat 

 through human alteration. The role of the estuary in 

 producing and rearing species important in Gulf fish- 

 eries is discussed, and the need for preservation of 

 estuarine nursery areas is stressed. 



It is becoming increasingly apparent that 

 estuaries play an important role in the production 

 of most finfish and shellfish harvested in coastal 

 fisheries, and that civilization influences the nutri- 

 ent capacity and productivity of these areas 

 (Skud and Wilson, 1960). 



Tampa Bay is one of the larger Gulf-connected 

 estuaries, encompassing some 350 square miles. 

 The primary purpose of this report is to enumerate 

 and discuss species inhabiting this estuary in early 

 life and entering Gulf fisheries as adults. The 

 secondary purpose is to appraise relative species 

 production between areas of the Bay as an aid in 

 evaluating the probable effects on biota of the 

 various engineering projects that are being pro- 

 posed. 



Man's ravages of estuarine areas in Florida are 

 progressing so rapidly that many species of fish 

 will disappear from these areas in the near future 

 (Springer and Woodburn, 1960). Pollution and 



Note. — Approved for publication November 11, 1964. 



1 Contribution No. 16, Bureau of Commercial Fisheries Biological Station, 

 St. Petersburg Beach, Fla. 



engineering projects are the greatest threat to the 

 survival of estuarine species (Thompson, 196 1 , and 

 Sykes, 1964 and 1965). These projects include 

 harbor improvements, navigation channels, flood- 

 and erosion-control structures, hurricane barriers, 

 and fills to create new waterfront land. These 

 alterations result in reduced water area. Adjacent 

 bottom, including submerged grass flats, is de- 

 stroyed by dredging, and the regimen of salinity 

 and water temperature is changed. Sediments 

 are added to the water, and damaging siltation 

 occurs on nursery areas inhabited by commercial 

 and sport fish species. 



Although the danger to native aquatic, animals 

 is recognizable, the full significance of estuaries in 

 the production and rearing of these organisms is 

 not completely understood. Odum (1960) em- 

 phasized the importance of conducting research at 

 both ends of the food chain to achieve a more com- 

 plete understanding of ecological systems. He 

 also implied that too many researchers start at a 

 point well up on the food chain — fish, for in- 

 stance — and work down. The East Gulf Estua- 



FISHERY BULLETIN! VOLUME 65, NO. 2 



369 



