Consequences of elevated temperatures on life‐history traits of an introduced fish, pumpkinseed Lepomis gibbosus

Life‐history reactions of a pumpkinseed Lepomis gibbosus population in north‐eastern France exposed to heated waters were studied. The study was conducted from 2001 to 2003 in an artificial reservoir, adjacent to a nuclear power plant, in which water temperatures are cool in winter (8·2–12·4° C) and rise early in spring (April: 14·7° C) nearly 5° C and 3° C over the temperature of its tributary, respectively. Fast growth among young‐of‐the‐year, precocious maturity and short life span were observed, in contrast to related studies. The short life span appeared to be the price paid for early maturity in breeding fish, which suffered high mortality rates just after their first reproduction.