Improved Models for Predicting Walleye Abundance and Setting Safe Harvest Quotas in Northern Wisconsin Lakes

Autor: Steven W. Hewett, Joseph M. Hennessy, Thomas A. Cichosz, Gretchen J. A. Hansen
Rok vydání: 2015
Předmět:
Zdroj: North American Journal of Fisheries Management. 35:1263-1277
ISSN: 1548-8675
0275-5947
DOI: 10.1080/02755947.2015.1099580
Popis: In Wisconsin, the management of Walleyes Sander vitreus relies on a set of log-linear regressions to predict Walleye abundance and to set safe harvest. The regression models predict mean Walleye abundance from lake area, but they ignore variability among years; they also predict equal Walleye populations in lakes with the same size and recruitment source. We evaluated three alternative models in terms of predictive accuracy and the risk of overharvest. We used 899 mark–recapture population estimates (collected between 1953 and 2013) from 219 lakes to develop and evaluate (1) a log-linear mixed-effects model that used all individual observations and estimated adult Walleye abundance from lake area and lake-specific deviations from the overall intercept; (2) a mixed-effects model that builds on model 1 by adding a linear fixed effect of sampling year; and (3) a mixed-effects model that builds on model 1 by adding a random year effect. Walleye abundance was positively correlated with lake area in all...
Databáze: OpenAIRE
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