Pierre-Olivier Benoit

McGill University
M.Sc. candidate

Supervisor: Chris Solomon
Beatrix Beisner
Start: 2012-05-01
End: 2014-12-20

Project

How the variation in dissolved organic carbon (DOC) concentrations in lakes influences fish growth: a multi-species study.
In fish, a fast evolution in both morphology and life histories traits is observed when populations are exposed to different environmental conditions and thus different selective pressures. Lakes receive substantial inputs of terrestrial organic matter from their watersheds that can have significant impacts on physical, chemical and biological aspect of lakes by its effect on light penetration and ressources availability. Ongoing environmental changes are expected to alter terrestrial inputs to lakes, but the implications of these changes for food webs and fish populations are unclear. With my research project, I want to evaluate what is the influence of the viariation in DOC (dissolved organic carbon) concentration in lake on fish growth. To do this, I will use individual length-at-age data for three different species that present important biological, morphological and behavioral differences: Lake trout (Salvelinus namaycush), Walleye (Sander vitreus) and Yellow perch (Perca flavescens). For each sampled lake, DOC concentration and other selected environmental variables will also be measured. For each species, the objective is to compare the growth (estimated with individual age and length data) of fish evolving in different DOC concentration. Including different species allow us to: 1- analyse lakes presenting a broader DOC concentration variation and 2- make the association between the variation in fish growth and the characteristics of each species.

Keywords

dissolved organic carbon, fish growth, traits d'histoire de vie, Perca flavescens, Salvelinus namaycush, Sander vitreus