Fish and Aquatic Conservation



illustration of a Bloater fish

Bloater

Coregonus hoyi (Milner, 1874)

Cool Facts

The maximum reported age for the bloater is 10 years.

SIZE: The common length for the bloater is 25.5 cm (10 inches) with a maximum reported length of 37 cm (14.5 inches).

RANGE: Bloaters are found in all of the Great Lakes except for Lake Erie and in Lake Nipigon in Canada.

HABITAT: Bloaters reside in freshwater lakes, but can also be found in rivers and streams.

DIET: Bloaters feed on zooplankton, aquatic insects and algae.

Natural History

The Bloater is a form of freshwater whitefish in one of the three sub-families of the salmon family. The Bloater is an important forage species for lake trout in the Great Lakes and for Atlantic salmon in Lake Ontario. Bloaters were an important commercial species in the Great lakes of North America from 1940 to 1960. Currently, they are still present in Lake Superior, Lake Michigan and Lake Huron.

Bloaters undergo early summer spawning migrations. Migrating bloaters ascend tributary streams to mate and release their eggs and milt over gravel and rocks. Bloaters often travel from dusk until late in the night during their spawning migrations to escape predation.

Conservation

The U.S. Fish and Wildlife Service (FWS) works with multiple agencies to create healthy brood stock to assist in the reintroduction of Bloaters in the Great Lakes. The FWS provides fertilized Bloater eggs from wild donor stock in Lake Michigan to support ongoing Bloater restoration in Lake Ontario.