Index Page | HTML Print Version

The Lake Sturgeon

The lake sturgeon (Acipenser fulvescens), largest and longest lived of any of our freshwater species, may reach a length of 2.5 m and weigh more than 135 kg. A slow maturing fish that has been known to live more than 150 years, it was once abundant in the large rivers and lakes of central and eastern North America, especially in the Great Lakes. Unfortunately, early reckless destruction followed by over-exploitation have reduced its numbers drastically. Not considered a sport fish, it now supports minor commercial fisheries in New-Brunswick, Quebec, Ontario, Manitoba and Saskatchewan.

In the Prairie Provinces, it occurs as far north as Seal River on the northwestern coast of Hudson Bay. In Alberta it occurs in the North Saskatchewan River, almost as far upstream as Edmonton; in Saskatchewan in the South Saskatchewan River, the Churchill River and Cumberland Lake; and in Manitoba primarily in Lake Winnipeg and the Assiniboine and Red Rivers.

The sturgeon family, of which the lake sturgeon is a member, is made up of 23 species distributed over the Northern Hemisphere in America, Europe and Asia. As a group, these fish are survivors of prehistoric times and exist today in much the same form as they did when the world was young.

All have cartilaginous skeletons and thick-set, torpedo-shaped bodies distinguished from those of other fishes by rows of hard, knobby, pointed bucklers running from head to tail. Between the rows of bucklers are five rows of bony, shieldshaped plates or scutes - one along the back and two along each side - which armour the body against attacks of predaceous, toothed fish. Other striking external features are a long, pointed, rooting snout; a row of four barbels or feelers under the snout in front; a round, protrusible, sucking mouth; a shark-like tail fin with upper lobe longer than the lower one.

The colour of the lake sturgeon varies with age. The young have large, black blotches on their sides, back, and snout, but these disappear as they grow older. The adults are a uniform olive-brown to grey on the back and sides, shading to white below. Usual size in the commercial catch is governed by the allowable mesh size of the nets. Total length ranges from 90 to 140 cm and weight from 4.5 to 35 kg.

This fish is a bottom dweller and its usual habitat lies in the shoal areas of large lakes and rivers. With its sensitive feelers it searches the bottom for food such as worms, the larvae of aquatic insects, molluscs, crustaceans, and small fish. Commercial fishing is carried out with gillnets, poundnets and set lines-long horizontal lines having many baited hooks attached by shorter lines and set on the bottom.

Although catches are low, lake sturgeon today sell for more per kilogram than any other of our freshwater species. Their firm, white, rich flesh is particularly delectable when smoked. Most of the catch is marketed in the United States where it is a gourmet item, as are also the processed eggs of the female, known as caviar.

Top of Page

Last updated : 2004-08-17

Important Notices