Growth rate and abundance of common fishes is negatively related to dissolved organic carbon concentration in lakes

Abstract

Dissolved organic carbon (DOC) can limit food web productivity in lakes, potentially imposing resource limitation on fishes. We asked whether the abundance or early growth rate of three fish species was negatively related to DOC in 59 lakes in southern Quebec, Canada, where DOC concentrations ranged from 4 to 16 mg·L−1 for lakes containing walleye (Sander vitreum) and yellow perch (Perca flavescens) and from 2.6 to 9 mg·L−1 for lakes containing lake trout (Salvelinus namaycush). Estimates of abundance and growth rate were more precise for walleye and lake trout than for yellow perch because of differences in sample size. Abundance was negatively related to DOC for walleye and perhaps also for lake trout and yellow perch. Early growth rate was negatively related to DOC for walleye and lake trout, but not for yellow perch. These results support a growing body of literature suggesting that the productivity of fish populations may be negatively related to DOC concentrations in lakes.