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USGS · 1000466

Age, growth, and food of northern pike in eastern Lake Ontario

David R. Wolfert·Terence J. Miller
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Abstract

Northern pike ( Esox lucius ) from eastern Lake Ontario were sampled with gill nets and trap nets in 1972-1973. Fish of age-groups IV, V, and VI were predominant in the catch. Although males were slightly longer after the 1st yr of life, females gained a 25-mm advantage in the 2nd yr and a 30-mm advantage in the 3rd yr. In later years, the increments of growth of males and females were similar. All males were mature after 2 yr and females after 3 yr. The stomachs of northern pike contained only fish; the alewife ( Alosa pseudoharengus ) was the principal forage species consumed. Electivity indexes for alewives, white perch ( Morone americana ), and yellow perch ( Perca flavescens ), the three most common species in the diet, indicated a positive selection for alewives that increased from June to October during a period when the relative abundance of alewives steadily decreased.

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David R. Wolfert, Terence J. Miller. 1978. Age, growth, and food of northern pike in eastern Lake Ontario. https://doi.org/10.1577/1548-8659(1978)107%3C696%3Aagafon%3E2.0.co%3B2

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