Alewife, Alewives
The alewife (Alosa pseudoharengus; pl.: alewives) is an anadromous species of herring found in North America. It is one of the "typical" North American shads, attributed to the subgenus Pomolobus of the genus Alosa. As an adult it is a marine species found in the northern West Atlantic Ocean, moving into estuaries before swimming upstream to breed in freshwater habitats, but some populations live entirely in fresh water. It is best known for its invasion of the Great Lakes by using the Welland Canal to bypass Niagara Falls. Here, its population surged, peaking between the 1950s and 1980s to the detriment of many native species of fish. In an effort to control them biologically, Pacific salmon were introduced, only partially successfully. As a marine fish, the alewife is a US National Marine Fisheries Service "Species of Concern".
Its common name is said to come from comparison with a corpulent female tavernkeeper ("ale-wife"), or, alternatively, from the word aloofe, possibly of Native American origin, that was used to describe this fish in the seventeenth and eighteenth centuries.
In southwestern Nova Scotia, alewife are referred to as kiacks (or kyacks). In Atlantic Canada it is known as the gaspereau, from the Acadian French word gasparot, first mentioned by Nicolas Denys. William Francis Ganong, New Brunswick biologist and historian, wrote:
Acadians named two rivers after the fish, the Gaspereau River in Nova Scotia and the Gaspereau River in New Brunswick.
Both anadromous and landlocked forms occur. The landlocked form is also called a sawbelly or mooneye (although this latter name is more commonly applied to Hiodon spp.) Adult alewife are caught during their spring spawning migration upstream by being scooped out of shallow, constricted areas using large dip nets. They are the preferred bait for the spring lobster fishery in Maine, and are eaten by humans, usually smoked.
Alewife reach a maximum standard length (SL) of about 40 centimetres (16 in), but have a typical SL of about 30 centimetres (12 in). The front of the body is deep and larger than other fish found in the same waters.
Alewife have bronze-colored heads and a grey-blue to greyish green dorsum. A humeral spot is often present. The tongue does not bear teeth. The peritoneum is light-colored with spots to dusky-appearing, an internal feature that distinguishes alewife from blueback herring (Alosa aestivalis), which have a dark peritoneum. The otolith is shaped like a letter "L", unlike its hooked shape in A. aestivalis. Additionally, the eye is larger than that of A. aestivalis; the width of the eye often exceeds the length of the snout in A. pseudoharengus.
Alewife populations have seen big declines throughout much of their range. Several threats have most likely contributed to their decline, including loss of habitat due to decreased access to spawning areas from the construction of dams and other impediments to migration, habitat degradation, fishing, and increased predation due to recovering striped bass populations.
In response to the declining population trend for alewives, the states of Massachusetts, Rhode Island, Connecticut, Virginia, and North Carolina have instituted moratoria on taking and possession.
In eastern Massachusetts, Alewife Brook flows through Arlington, Cambridge, and Somerville to the Mystic River. The brook gives its name to the Alewife Brook Parkway and the Alewife Brook Reservation. The Red Line (MBTA) of Boston's T ends at the Alewife station, so the name of this fish adorns the front of every northbound Red Line train. An extensive habitat restoration and education project, combined with a fish ladder with monitoring cameras, is yielding increasing numbers of alewife back in the improving Mystic River watershed.
The alewife is a US National Marine Fisheries Service Species of Concern, about which the National Oceanic and Atmospheric Administration, National Marine Fisheries Service, has some concerns regarding status and threats, but for which insufficient information is available to indicate a need to list the species under the US Endangered Species Act.
