Bottom-depth preference of Lake Erie walleye: informing fishery management across Lake Erie

Session: Restoration and Management of Great Lakes Fishes (3)

Jordan Matley, University of Windsor, [email protected]
Matthew Faust, [email protected]
Christopher Vandergoot, USGS - Great Lakes Science Center, [email protected]
Graham Raby, University of Windsor, [email protected]
Yingming Zhao, Ontario Ministry of Natural Resources, [email protected]
Tom MacDougall, Ministry of Natural Resources, [email protected]
Charles Krueger, CSIS, Michigan State University, [email protected]
Aaron Fisk, University of Windsor, [email protected]

Abstract

Lake Erie walleye (Sander vitreus) undergo large-scale seasonal migrations between shallow spawning habitats and deeper foraging areas. Historically, walleye fishery quotas have been derived based on a presumed preferred bottom-depth of <13m, however limited support to the efficacy of this designation has been given. The goal of this study was to estimate the bottom-depth preference of walleye throughout their seasonal lake-wide migrations using acoustic telemetry to investigate the validity of this ‘13m habitat’ guideline. Data from >1000 individuals during >5 years of acoustic telemetry tracking were used to explore monthly variation in bottom-depth preference affiliated with stock, sex, and age of walleye in both western and eastern basins of Lake Erie. The results identified seasonal fluctuations in bottom-depth selection across stocks which coincided with spawning/foraging migrations. For example, shallow waters <6m deep were preferred during spawning periods of March and April, and deep water (>13m) were positively selected for during summer and fall, coinciding with cross-lake movements. Winter patterns favoured moderate depths (7-13m), when walleye returned to spawning areas. This study demonstrates lake-wide similarities in bottom-depth selection across walleye stocks, despite differences in migration patterns and highlights the limitations of current quota specifications.

Twitter handle of presenter
@JK_Matley