White Sucker (Catostomus commersoni)

This is one of the most widespread and abundant suckers, found only in North America.

Identification

White suckers are inconspicuously colored, usually in drab hues of white, yellow, and pink. The upper half of the fish is typically more darkly colored than the lower half. Although an adult has little dark pigmentation, a juvenile has three lateral black blotches halfway up the side of the body: one between the dorsal fin and opercle, one below the dorsal fin, and one on the caudal peduncle. The body is elongate and nearly circular in cross-section. The white sucker has rather small scales that get larger near the posterior.

Age/Size

The white sucker is a medium-size fish, reaching up to 18 inches or more in length and up to 8 pounds in weight. The largest individuals may be as old as 17 years, but the normal life expectancy is between 12 and 15 years. Sexual maturity is reached at about the same time in both sexes. The first spawning occurs between 3 and 5 years of age, depending on the region.

Life history/Spawning behavior

White suckers make long upstream spawning migrations in the early spring. The spawning season may extend from late March into early July in some areas. Upstream migration may be triggered by increasing water temperature or stream flow that occurs during this time of year. The suckers move into deep pools and congregate before spawning. They then gather and spawn in areas of clean gravel substrate.

Males and females line up next to each other on the bottom of the stream, then shake violently, releasing eggs and sperm as they bury the eggs in the substrate. In lakes, they perform this activity in shallow shoals or may move upstream into rivers. White suckers darken in coloration during spawning. The male becomes olive colored on the upper portion of the body and may develop a pinkish lateral stripe.

Food and feeding behavior

Like most suckers, this species feeds on a variety of benthic organisms and organic nutrients. Its primary diet includes burrowing insect larvae that are sucked up and sifted in its gill rakers. Midge larvae, small crustaceans, algae, and detritus are the most common
foods.

Other Names

black sucker, black mullet, brook sucker, carp, common sucker, common white sucker, eastern sucker, mud sucker, fine scaled sucker, grey sucker, mullet; French: meunier noir, cyprin-sucet.

Distribution

The white sucker is one of the most widely distributed suckers in North America. It ranges from Canada south to the southern Appalachian Mountains and west into Utah and Idaho. Its range has expanded from bait bucket transfers when anglers release unused baitfish.

Habitat

The white sucker is a habitat generalist, living in all types of freshwater environs. It occurs in lakes, rivers, ponds, reservoirs, and even some small streams. It can exist in fairly degraded systems, being tolerant of some turbidity, pollution, siltation, and eutrophication. In rivers, adults frequently inhabit deep pools, whereas juveniles live in stream margins and backwaters.