水産養殖研究開発ジャーナル

概要

Genetic Evidence for Sympatric Populations of Yellow Perch (Perca flavescens) in Lake Saint-Pierre (Canada): the Crucial First Step in Developing a Fishery Management Plan

Christelle Leung, Pierre Magnan and Bernard Angers

To ensure the persistence of species facing anthropogenic pressures, an understanding of the dynamics and mechanisms that structure populations is of major importance. Determining the presence of distinct populations is a first step when sympatric populations are suspected. Yellow perch ( Perca flavescens ) is exploited by sport and commercial fishing in Lake Saint-Pierre (Quebec, Canada). Because habitat characteristics are spatially structured and this species is known to display natal site fidelity, this study’s aim was to assess whether sympatric populations of yellow perch coexist in Lake Saint-Pierre. Low genetic differentiation is predicted due to the recent colonization of the system (<8,000 years). Simulations were first performed to confirm that population differentiation is better depicted using AFLP than microsatellite markers. A survey of the variation throughout the entire genome was then performed using the AFLP approach. To link individuals to their natal site, recently emerged larvae from different cohorts captured at different stations were analyzed. Results from three distinct AFLP surveys indicated a correlation between the genetic composition of individuals and geographic sites. These results confirmed the presence of multiple sympatric populations in Lake Saint-Pierre, resulting from natal site fidelity. While the genetic differentiation is very low, the management of this species should take into account the existence of distinct population structures.