Transactions of the American Fisheries Society
Food of and Habitat Use by Juveniles of Species of Micropterus and Morone in a Southwestern Reservoir
WILLIAM J. MATTHEWS, FRANCES P. GELWICK, and JAN JEFFREY HOOVER
Biological Station and Department of Zoology, University of Oklahoma, Kingston, Oklahoma 73439, USA
Abstract.: We determined food of and habitat use by juvenile largemouth bass Micropterus salmoides, spotted bass Micropterus punctulatus, striped bass Morone saxatilis, and white bass Morone chrysops over a 6-year period (1981?1986) in Lake Texoma, Oklahoma, Texas. Largemouth bass, spotted bass, and white bass are native to the river basin and reservoir, whereas striped bass are introduced. Diet overlap (based on numbers or weight) was highest between the two species of Morone and between the two species of Micropterus, and was also substantial (if based on prey weight) between largemouth bass and striped bass and between largemouth bass and white bass. Diet overlap between field-caught striped bass and largemouth bass was sufficiently high to suggest potential trophic competition between juveniles, but the two species occupied substantially different habitats as juveniles. Spatial segregation seemed sufficient to ameliorate potential competition between the latter two species. A laboratory experiment to test for trophic shifts by coexisting juvenile largemouth bass and striped bass indicated nonsignificant or only marginally significant changes in diets of largemouth bass in the presence of striped bass. Juvenile striped bass overlapped more in habitat and foods with juvenile white bass than with largemouth bass, suggesting a greater potential for negative interactions between the two species of Morone.