Deepwater Demersal Fish Community Collapse in Lake Huron

• DOI: 10.1577/t07-141.1
• Publication Date: 2008-12-15T15:31:26Z
• Authors: Stephen C. Riley; Edward F. Roseman; S. Jerrine Nichols; Timothy P. O'Brien; Courtney S. Kiley; Jeffrey S. Schaeffer
• Keywords: Notropis; Neogobius; Demersal zone; Demersal fish; Round goby; Common species

Abstract Long‐term fish community surveys were carried out in the Michigan waters of Lake Huron using bottom trawls from 1976 to 2006. Trends abundance indices for common species (those caught 10% or more trawl tows) estimated two periods: Early (1976‐1991) and late (1994‐2006). All significantly decreased during period with exception johnny darter Etheostoma nigrum spottail shiner Notropis hudsonius , which showed no significant trends, round goby Neogobius melanostomus increased abundance. Percentage decreases between 1994‐1995 2005‐2006 ranged 66.4% 99.9%, seven by than 90%. The mean biomass all 2006 was lowest observed time series less 5% that mid‐1990s. number captured per has also since Several factors, including recent invasion lake multiple exotic species, may have contributed these declines, but insufficient published data are currently available determine factors most important. Our observations suggest changes occurred ecology extent indicates deepwater demersal is undergoing collapse.