Size-Related Mortality of Tournament-Caught Largemouth Bass

Prerelease mortality of largemouth bass Micropterus salmoides was recorded at major fishing tournaments on Sardis Reservoir, Mississippi, during 1989–1991. Mortality of large fish (total length > 18 in) averaged 29% and was significantly greater (P < 0.05) than the 9% average mortality suffered by small (12–14-in) fish. Mortality increased with water temperature and mean number of fish per boat. The significantly higher mortality of large fish should be considered in efforts to enhance the survival of fish released after tournaments. In waters where tournament fishing effort and catch are high, size-related mortality could alter the population's size structure, reduce the potential for trophy fish, or create public relations problems for tournaments because of their perceived effect on fishery resources.