Predator-induced delayed maturity in bluegill sunfish (Lepomis macrochirus): variation among populations


life history, predation, phenotypic plasticity, bluegill sunfish, nonlethal effects of predators


Previous studies suggested that differences in age at maturity among populations of bluegill sunfish (Lepomis macrochirus) were not genetically based, but rather were a phenotypic response to the presence of predators. I conducted two experiments to determine if the presence of largemouth bass affected age at maturity in bluegill sunfish. Bluegills from three populations were tested to see if the response to the threat of predation varied among source populations. Juvenile bluegills were maintained in the presence of predators or in controls with no contact with predators. Refuge use and growth were monitored during the experiments and reproductive activity was evaluated when bluegills reached age 1. Bluegills from one population exhibited delayed maturity in the presence of predators. Individuals from the other two populations showed no significant differences between predator and control treatments. The population that responded to the presence of predators had a history of high predation levels over the past 30–40 years. The other populations had a history of low levels of predation. This study suggests that presence of predators can induce phenotypic shifts in age at maturity of bluegills, but that the magnitude of response varies among populations in a manner consistent with historical patterns of coexistence.

Original Publication Citation

Mark C. Belk. 1998. Predator-induced delayed maturity in bluegill sunfish (Lepomis macrochirus): variation among populations. Oecologia, 113: 203-209.

Document Type

Peer-Reviewed Article

Publication Date







Life Sciences



University Standing at Time of Publication

Full Professor