White Sucker

Latin Name

Catostomus commersonii

Group Name

Freshwater

Taxonomy details

Habitat

White suckers are freshwater fish native to North America. They occur all across Canada, from Newfoundland and Labrador to British Columbia, as well as in the Yukon and Northwest Territories and in all of the Great Lakes. They are found in both lakes and rivers, usually in shallow water where they feed on bottom on worms, clams, insect larvae and occasionally fish eggs. White suckers are robust and adaptable fish, surviving many adverse water conditions that other fish could not tolerate. This coupled with their high abundance and widespread occurrence has lead to the use of white suckers as environmental monitors for toxic chemicals and pulp mill effects, and various diseases including papillomas and liver tumours. They are not usually fished except for bait. White sucker serve as food for pike, muskellunge, bass, walleye, burbot, Atlantic salmon, brook trout and a variety of birds and mammals.

Species Description

White suckers are a bottom-feeding fish with the downturned snout characteristic of other suckers. Their mouth is round and rimmed with thick lips. They have a streamlined body with a single, flat dorsal fin, and a tail fin with a strong indent. White suckers are normally olive-coloured on top and cream-coloured on their underside. During spawning they will become darker. Spawning occurs in the spring at a temperature of 10ºC when runs numbering as high as the thousands ascend small streams with females spawning from 20,000 to 50,000 eggs each over gravel substrate. They can grow to about 50 centimetres in length and 2 kg in weight.