Evidence of predatory control of yellow perch (Perca flavescens) recruitment in Lake Erie, U.S.A

Autor: F. J. Margraf, K. J. Hartman
Rok vydání: 1993
Předmět:
Zdroj: Journal of Fish Biology. 43:109-119
ISSN: 1095-8649
0022-1112
DOI: 10.1111/j.1095-8649.1993.tb00414.x
Popis: Predation can be a major factor in recruitment success of yellow perch (Perca flavescens Mitchitl). Trawl catches of age-0 yellow perch in western Lake Erie declined from 870·3 per trawling h in June to 3·3 per trawling h in late July 1988. Coincident with the decline in relative abundance of age-0 yellow perch we found large numbers of age-0 yellow perch in the stomachs of small walleyes (Stizostedion vitreum Mitchill). From this evidence we hypothesized that predation by walleyes may have caused the demise of the 1988 year-class of yellow perch. We used a population and bioenergetics modelling approach to estimate the impact of walleye predation on the abundance of age-0 yellow perch. Modelling showed that 6·8 × 109 age-0 yellow perch that had attained 18 mm total length (t.l.), were eaten by small (age-2 and younger) walleye from June through July 1988. We estimated that walleye ate 28·4–89·7% of the yellow perch reaching 18 mm t.l. during 1988. The majority of this predation (77% of total) was by the abundant age-2 cohort of walleyes. We concluded that, even in a large system such as Lake Erie, predation can play a major role in structuring year-class strength of yellow perch and, thus, management of percid fisheries should be conducted on a fish-community basis.
Databáze: OpenAIRE
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