Premium
Effects of Vegetation Removal on Bluegill and Largemouth Bass in Two Minnesota Lakes
Author(s) -
Pothoven Steven A.,
Vondracek Bruce,
Pereira Donald L.
Publication year - 1999
Publication title -
north american journal of fisheries management
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.587
H-Index - 72
eISSN - 1548-8675
pISSN - 0275-5947
DOI - 10.1577/1548-8675(1999)019<0748:eovrob>2.0.co;2
Subject(s) - micropterus , bass (fish) , fishery , lepomis macrochirus , vegetation (pathology) , abundance (ecology) , biology , ecology , environmental science , fish <actinopterygii> , medicine , pathology
Abundance and growth of bluegill Lepomis macrochirus, diet and growth of largemouth bass Micropterus salmoides, and abundance of age‐0 largemouth bass were evaluated in two treatment and three reference lakes in Minnesota to assess the effects of whole‐lake herbicide treatments. Lakes were evaluated 1 year prior (1993), during (1994), and after (1995) treatment. In reference lakes, vegetation, fish growth, abundance, and diet remained relatively unchanged throughout the study. Herbicide applications in May 1994 decreased the percentage of sampling stations with vascular vegetation from 100% to 33% in Parkers Lake and 63% in Zumbra Lake between Aug 1993 and 1994. Vegetation returned to some areas of Parkers Lake in 1995 (77%) but continued to decline in Zumbra Lake (43%). Purse‐seine catch per effort (CPE) of small bluegill (60–100 mm) decreased following treatment but returned to pretreatment levels the following year, whereas CPE of large bluegill (>100 mm) increased in 1994 in trap nets and remained constant in gill nets and large bag seines. Age‐0 largemouth bass abundance was not affected by vegetation removal. Growth of bluegills and largemouth bass was greater in 1994 than in the previous 4–5 years. Largemouth bass stomachs contained more fish prey and were empty in fewer instances only during 1994 in Zumbra Lake. Because few treatment effects were sustained during the posttreatment year, whole‐lake treatments with herbicide may not be a useful tool for long‐term management of bluegills or largemouth bass unless annual or semiannual treatments are an acceptable social, biological, and economic strategy.