Abstract
The present study surveys the trophic interrelationships of 26 demersal fishes inhabiting the continental shelf of the northern Gulf of Mexico. Volumetric stomach content analyses were carried out on 4,550 specimens. Fishes were collected at 128 stations between Brownsville, Texas and St. Andrew's Bay, Florida in depths of approximately 3 to 200 meters. Within each species, fish were grouped by size, depth, and geographical location in order to compare variations in food habits due to these factors. Food habits of the individual species are discussed emphasizing trends in diet by food categories, transitions associated with growth, and variations associated with geographical location. Feeding periodicity is discussed for those species where data were available. From this detailed information, trends in the life history and food habits of continental shelf fishes are proposed. Larger individuals of a species are indicated to spawn in deeper waters. Larval and juvenile fishes subsequently enter the water column, especially the supra-benthic zone, where they undergo a planktonic stage as they are transported by currents toward shallower waters. They eventually settle to the bottom to lead a demersal existence gradually moving offshore to complete the life cycle. This trend in life history pattern is reflected in the ontogenetic food habit transitions. Larvae and juveniles feed largely on zooplankton. The importance of zooplankton decreases with ontogenetic development except in certain planktivorous species. As the importance of zooplankton decreases, benthic organisms increase in importance..
Rogers, Robert Merrill (1977). Tropic interrelationships of selected fishes on the continental shelf of the northern Gulf of Mexico. Texas A&M University. Texas A&M University. Libraries. Available electronically from
https : / /hdl .handle .net /1969 .1 /DISSERTATIONS -369992.