Changes in Walleye Fecundity and Egg Size Before, During, and After Rehabilitation of the Red Lakes Fishery

Authors

Benjamin J. Miller
Benjamin D. Erb

Document Type

Article

Abstract

The Red Lakes in northern Minnesota experienced a major Walleye Sander vitreus fishery crash in the late 20th century, but has since recovered to record abundances and supports a major commercial and recreational fishery. Fecundity is an integral aspect of recruitment that can contribute greatly to the understanding of fishery population dynamics. To elucidate the effects of varying Walleye densities and exploitation rates on fecundity and egg size in years 1989 (overexploited fishery), 2004 (recovering fishery), and 2017 (recovered fishery), we analyzed linear models that related fecundity or egg size to morphological features for these three sampling periods. Walleyes were collected spring 2004 (n=30) and 2017 (n=30) in the Tamarac River. Fecundity data from 1989 were provided by Bushong (1990). Fecundity was higher in 2004 and 1989 than in 2017. Egg size was significantly greater in 2017 than in 1989. Considerable distinctions in Walleye size at spawn existed between all sampling years. Variance in fecundity as well as egg and fish size between fishery status scenarios is likely attributable to varying exploitation rates and related Walleye densities; these two factors were shown to be good predictor variables. Models incorporating fishery status were developed and for certain management applications, these models could provide a higher degree of selectivity and estimation accuracy for fishery managers.

Publication Date

2019

Comments

Faculty sponsor: Dr. Andrew Hafs, Department of Biology, Aquatic Biology Program

Recommended Citation

Miller, Benjamin J. and Erb, Benjamin D., "Changes in Walleye Fecundity and Egg Size Before, During, and After Rehabilitation of the Red Lakes Fishery" (2019). Journal of Earth and Life Science. 24.
https://pines.bemidjistate.edu/j-earth-life-sci/24