Title

Diet Breadth and Variability in Sander spp. Inferred from Stable Isotopes

Document Type

Article

Publication Date

6-2015

Departmental Paper Identifier

NRM-180

Keywords

Sander vitreus, sauger, Sander canadensis, Missouri River, hybridization

Abstract

We used stable isotopes of carbon and nitrogen to evaluate trophic similarity between saugerSander canadensis and walleye S. vitreus in three Missouri River impoundments characterized by unique differences in riverine habitat. Mean δ15N was similar for sauger and walleye in each reservoir ranging from 15.7 to 17.8‰ for sauger and 15.2 to 17.7‰ for walleye. However, mean δ13C was greater for sauger (−24‰) than for walleye (−25‰) in Lake Oahe (lacustrine habitat), where rainbow smelt Osmerus mordax is an important prey species for walleye. Variation in δ15N and δ13C values was similar between walleye and sauger in Lewis and Clark Lake (riverine habitat), but was greater for sauger than for walleye in Lake Oahe, implying that in pelagic environments, sauger exhibit a larger diet breadth and lower diet consistency compared with walleyes. Isotope analyses support observations from traditional gut content studies that diet overlap between sauger and walleye varies with environmental conditions and is more similar in riverine food webs than in large lakes and impoundments.

Publication Title

River Research and Applications

Volume

32

Issue

5

First Page

984

Last Page

991

DOI of Published Version

10.1002/rra.2916

Publisher

John Wiley & Sons

Rights

Copyright © 2015 John Wiley & Sons, Ltd.