Longjaw cisco

The long jaw whitefish (Coregonus alpenae ) is an extinct Tiefwassermaräne that occurred usually at depths of 100 meters or more in the Lakes Huron, Michigan and Erie. Its scientific name is derived from the place in Alpena Michigan.

Description

It reached an average length of 28 cm. The largest long jaw whitefish was 54.6 cm long, weighed 1.8 kg and was caught in 1932 in Manistique, Michigan. The body was elongated and compressed on the sides, but resilient. The heavy head was short and broadened. The wide mouth was slightly rounded. The eyes were trained poorly. The heavy jaw jutted above the upper jaw also. The jaws were extended and usually without pigment on the anterior edge. The long jaw whitefish generally had a silvery color with a pink or purple sheen. The back was bluish or greenish, silvery flanks and underparts white. The pigmentation of the pines and the fins was very bright

Since the classification of whitefish is quite complicated, many scientists believe that the long pine - Whitefish was not a distinct species, but a different population physically long individuals of short pine whitefish (Coregonus zenithicus ).

Food and lifestyle

The spawning period was in the late autumn. Their main diet consisted of zooplankton such as the Reliktkrebschen ( Mysis relicta ).

Extinction

The causes of their extinction were overfishing and pollution of the Great Lakes and the parasitism by the invasive sea lamprey. The highlight of the commercial catch actions was during the 1930s, when a third of vendace caught consisted of this kind. It was sold as a bloater. In the 1950s it was already extinct in Lake Erie. In 1961, she was seriously depleted in Lake Michigan. 1967 this species was not detected in the commercial fishing and in 1975 the last copy in the Georgian Bay in Lake Huron in Ontario was seen.