Abundance and Density of Demersal Fishes on the West Florida Shelf, January 1978

Bottom trawl stations (338) were sampled on the West Florida Shelf from the NOAA vessel FRS OREGON II in January 1978, to assess fish faunal composition, abundance and density on trawlable bottom. Both total catch and fish catch rates were higher in the northern part of the study area, and were generally highest in shallow water.

At least 246 species of fish, in 71 families, were present in the trawl catches. Dominant families by weight were: Haemulidae, Sparidae, Sciaenidae, Serranidae and Bothidae. Fish density was approximately twice as high in the northern part of the study area as in the southern part. Apparent standing stock for 9–93 m depths was 433.0 thousand metric tons. Small numbers of commercially important invertebrates (Penaeus setiferus, P. duorarum, Sicyonia brevirostris, Scyllarides nodifer) were also taken. Sponges were abundant over much of the study area.

Qualitatively, West Florida Shelf catches resembled those from other areas of the northern Gulf, but dominant families and species were considerably different. Differences in fish faunal composition are probably due to differences in bottom type; the West Florida Shelf area sampled is largely "live bottom," whereas much of the rest of the northern Gulfis soft bottom, consisting of terrigenous materials. Fish fauna of the West Florida Shelf is similar to that of the South Atlantic Bight, probably due to the presence of live bottom in both areas.