alewife

alewife: see herring.

Important North American food fish (Pomolobus, or Alosa, pseudoharengus) of the herring family. The alewife grows to about 1 ft (30 cm). Most populations spend several years along North America's Atlantic coast before ascending freshwater streams to spawn each spring in ponds or sluggish rivers.

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The alewife (Alosa pseudoharengus) is a species of herring. There are anadromous and landlocked forms. The landlocked form is also called a sawbelly or mooneye (although this latter name is more commonly applied to Hiodon spp.). The front of the body is deep and larger than other fish found in the same waters, and its common name is said to come from comparison with a corpulent female tavernkeeper ("ale-wife"). In Atlantic Canada it is known as the gaspereau. More locally, in southwestern Nova Scotia it is called a kiack (or kyack). This fish has, in the past, been used as a baitfish for the lobster fishing industry. It is also used for human consumption, usually smoked. It is caught (during its migration up stream) using large dip nets to scoop the fish out of shallow, constricted areas on its migratory streams and rivers. It is one of the "typical" North American shads of the subgenus Pomolobus. (Faria et al. 2006)

In the North American Great Lakes

Alewives are perhaps best known for their invasion of the Great Lakes by using the Welland Canal to bypass Niagara Falls. Alewives colonized the Great Lakes and became abundant mostly in lakes Huron and Michigan. They reached their peak abundance by the 1950s and 1960s. Alewives grew in number unchecked because of the lack of a top predator in the lakes (lake trout were essentially wiped out around the same time by overfishing and the invasion of the Atlantic sea lamprey). For a time, alewives, which often exhibit seasonal die offs, washed up in windrows on the shorelines of the Great Lakes. Their control was the impetus for the introduction of various Pacific Salmon species (first coho, and later the chinook salmon) to act as predators on them. This caused the development of a salmon/alewife fish community, popular with many sport anglers. Alewives, however, have been implicated in the decline of many native Great Lakes species through competition and predation.

References

• (2006): A molecular phylogenetic perspective on the evolutionary history of Alosa spp. (Clupeidae). Molecular Phylogenetics and Evolution 40(1): 298–304. (HTML abstract)

Footnotes