Phenotypic shifts in white perch life history strategy across stages of invasion

Abstract

Successful invasive species must pass through several invasion stages, and life history or trophic strategies allowing for successful transitions may change as the species advances from one stage to the next. To evaluate the role of life history shifts in the invasion success of white perch (Morone americana), age and length at maturity, gonadosomatic index, and growth were compared across three invasive reservoir populations ranging from 1, 11, and 21 years since initial detection. Individuals in the newly introduced population exhibited increased growth and had higher mean reproductive investment than the two established populations across both study years. Individuals in the newest population also matured earlier than those in the older populations in 2009, but maturity schedules did not differ in 2010, possibly due to changes in environmental conditions causing life history shifts in both older populations. Overall, it appears that life history plasticity confers an important advantage to invasive species, allowing them to adapt for successful transitions throughout the invasion process, as well as to local conditions within the invaded system once they become fully integrated into established communities.