Fish Community of Lake Huron

Lake Huron has a rich aquatic habitat diversity that includes shallow embayments, numerous tributaries, shallow mid-lake reef complexes, archipelagos, and profundal regions. These habitats provide support for cool and cold water fish populations. Diversity of fishes in Lake Huron reflects post-glaciation colonization events, accidental and intentional introductions of non-indigenous species, and extinctions.

Annual surveys of forage fishes in Lake Huron are used to determine the availability of food for native, introduced, and naturalized predators. Prey abundance has been depressed in Lake Huron since 2004 due to dramatic declines in alewives and continued suppression of benthic species such as deepwater and slimy sculpins. Declines in benthic macroinvertebrate abundance and increases in non-indigenous dreissenid mussels may be linked to declines in prey fish populations in Lake Huron. The prey shortage prompted management agencies to reduce the level of stocked predators in attempts to relieve predation pressure. The continued depression of forage species biomass in the main basin of Lake Huron suggests that predators will continue to face potential prey shortages during 2008.

While the exact mechanisms of interactions (competition, predation, and thiamine) between alewives and other fishes in Lake Huron remain unclear, surveys have shown increases in abundance for several species having pelagic life history stages following the decline of alewives. Five consecutive years (2003-2007) of above average juvenile bloater densities have been observed; evidence of increases in bloater recruitment; continued production of wild lake trout; and the highest juvenile rainbow smelt abundance in the 15-year time series. Other surveys have shown repeated record year-classes of walleye and yellow perch in Saginaw Bay and southern Lake Huron associated with declines in alewives. Additionally, in 2006 lake-wide high densities of emerald shiners were observed in standard acoustic surveys of Lake Huron and evidence of cisco recruitment was found in Georgian Bay and the North Channel in 2007.

Reports

Status and Trends of the Lake Huron Deepwater Demersal Fish Community, 2008

Status and Trends of Pelagic Prey Fish in Lake Huron, 2007

Status and Trends of the Lake Huron Deepwater Demersal Fish Community, 2007

Status and Trends of Pelagic Prey Fish in Lake Huron's Main Basin, 2006

Status and Trends of the Lake Huron Deepwater Demersal Fish Community, 2006