Density-dependent and environmental influences on juvenile walleye Sander vitreus (Mitchill) survivorship in northern Wisconsin lakes

Logan R. Zebro; Joseph T. Mrnak; Stephanie L. Shaw; Steven R. Chipps; Greg G. Sass

doi:10.1111/fme.12591

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Density-dependent and environmental influences on juvenile walleye Sander vitreus (Mitchill) survivorship in northern Wisconsin lakes

Logan R. Zebro·Joseph T. Mrnak·Stephanie L. Shaw·Steven R. Chipps·Greg G. Sass

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Abstract

Walleye, Sander vitreus (Mitchill), natural recruitment has declined in northern Wisconsin lakes over time. Age-0 and age-1 walleye relative abundance (catch per unit effort; CPE) data from northern Wisconsin (1986–2019) were used to test for abiotic (i.e. lake characteristics and temperature variables) and biotic (age-0 and age-1 CPE) factors influencing age-0 to age-1 walleye mortality. Age-0 to age-1 walleye mortality was elevated at high age-0 CPE and variable at low age-0 CPE, which indicated strong density-dependence. Environmental factors such as spawning and ontogenetic phenology (climate change and ice-off dates), trophic mismatches, and metabolic and consumptive demand influenced age-0 to age-1 walleye mortality less strongly. Elevated age-0 to age-1 walleye mortality at low age-0 CPE supports previous findings of depensatory recruitment dynamics in northern Wisconsin walleye populations. Additional research is needed to address elevated juvenile walleye mortality at low adult stock sizes and/or with declining natural recruitment to inform management decisions.

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Fisheries Management and Ecology Article

Source-reported bounding extent: 42.49192° to 47.07757° latitude; -92.888035° to -86.805415° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

Logan R. Zebro, Joseph T. Mrnak, Stephanie L. Shaw, Steven R. Chipps, Greg G. Sass. 2022-08-12. Density-dependent and environmental influences on juvenile walleye Sander vitreus (Mitchill) survivorship in northern Wisconsin lakes. https://doi.org/10.1111/fme.12591

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