Title

Novel molecular approach demonstrates that turbid river plumes reduce predation mortality on larval fish

Document Type

Article

Publication Date

2014

Publication Title

Molecular Ecology

Volume

23

Issue

21

First Page

5366

Last Page

5377

DOI

10.1111/mec.12927

Keywords

determine diet; dna; environment; foraging; great-lakes; juvenile fish; Perca flavescens; perch perca-flavescens; recruitment; stage; stomach content DNA; survival; turbidity; water; yellow perch

Abstract

Turbidity associated with river plumes is known to affect the search ability of visual predators and thus can drive top-down' impacts on prey populations in complex ecosystems; however, traditional quantification of predator-prey relationships (i.e. stomach content analysis) often fails with larval fish due to rapid digestion rates. Herein, we use novel molecular genetic methods to quantify larval yellow perch (YP) in predator stomachs in western Lake Erie to test the hypothesis that turbidity drives variation in larval predation. We characterize predator stomach content DNA to first identify YP DNA (single nucleotide polymorphism) and then quantify larval YP predation (microsatellite allele counting) in two river plumes differing in turbidity. Our results showed elevated larval YP predation in the less turbid river plume, consistent with a top-down impact of turbidity on larval survival. Our analyses highlight novel ecological hypothesis testing using the power of innovative molecular genetic approaches.

Comments

This is an accepted manuscript version of an aritcle whose version of record was published in:Molecular Ecology: http://dx.doi.org/10.1111/mec.12927