Comparison of lake trout (Salvelinus namaycush) fatty acid signatures in the Finger Lakes

Abstract

Fatty acid signatures (FAS) can be used to study predator-prey relationships in aquatic food-webs and provide long-term foraging patterns that can reflect the diet composition of predators based on the principle “you are what you eat”. Lake trout Salvelinus namaycush is a native species in the Great Lakes region that relies on different prey throughout the Finger Lakes and therefore we predict that they will present different FAS among lakes. Lake trout were collected from six Finger Lakes between 2016 and 2020. FAS from lake trout were quantified using gas chromatography/mass spectrometry. Our results indicate that lake trout FAS significantly differed among the six Finger Lakes (ANOSIM, global R = 0.709, P < 0.001) and were characterized by concentrations associated with pelagic and benthic foraging. These results will ultimately be compared with FAS of prey species to evaluate lake trout diet composition in each Finger Lake.