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Diet and feeding periodicity of ruffe in the St. Louis River estuary, Lake Superior

January 1, 1995

Ruffe Gymnocephalus cernuus, a percid native to Europe and Asia, is established in the Lake Superior drainage and could have negative impacts on native fish through competition for forage and predation on fish eggs. We investigated the diet of ruffes in the 4,654-ha St. Louis River estuary in May–October 1989–1990 and the feeding periodicity of ruffes in two adjacent habitats during five 24-h periods in summers 1990–1991. Ruffes were primarily benthophagous. Age-0 ruffes fed mostly on cladocerans and copepods in early summer and midge larvae (Chironomidae) in late summer and fall. Adult ruffes less than 12 cm fed mostly on midges and other macrobenthos but also consumed large numbers of microcrustaceans. Adult ruffes 12 cm and larger fed mostly on midges, burrowing mayflies Hexagenia spp., and caddisflies (Trichoptera). Ruffes consumed few fish eggs. Adult ruffes in deeper waters and all age-0 ruffes fed throughout the day as indicated by weight patterns of stomach contents. However, adult ruffes generally moved to shallower waters at night to feed most heavily. Results of this study indicate that ruffes will probably compete with other benthic-feeding fishes such as yellow perch Perca flavescens and trout-perch Percopsis omiscomaycus.

Publication Year 1995
Title Diet and feeding periodicity of ruffe in the St. Louis River estuary, Lake Superior
DOI 10.1577/1548-8659(1995)124<0356:DAFPOR>2.3.CO;2
Authors Derek H. Ogle, James H. Selgeby, Raymond M. Newman, Mary G. Henry
Publication Type Article
Publication Subtype Journal Article
Series Title Transactions of the American Fisheries Society
Index ID 1000810
Record Source USGS Publications Warehouse
USGS Organization Great Lakes Science Center