Suckers are most easily distinguished by their small mouths and large fleshy lips. They have no barbs like catfish, no rigid spines in the dorsal and anal fins like perch and catfish, and no fatty fins like trout. Suckers are tough fish, slightly compressed at the sides. Most are medium-sized, but adults range from 6 inches (Roanoke hogsucker, Hypentelium roanokense) to over 33 pounds (buffalo). Most suckers do not have a bright or distinctive color. Many have an almost metallic sheen in shades of gold, green, purple, or white. Their coloration becomes more intense during breeding, when many species darken and develop lateral stripes. Reproductive adults also have hardened tubercles on the anal and caudal fins and head. Juveniles usually have a more distinct color pattern, with several saddles on the back and dark spots on the sides for camouflage.
Suckers are widespread, occurring throughout North America from the Arctic Circle to Mexico and from the east coast to the west coast. The white sucker (Catostomus commersoni) is one of the most widespread fishes in North America.
Suckers inhabit all types of freshwater habitats, including rivers, lakes, and small streams. Most fluvial species live in areas with moderately fast currents and moderate depths. The largest fish live in large lakes and the deep basins of large rivers. Because of their large size, they do not need to seek shelter from predators, so they often coexist with bass and trout in deep pools. A common misconception is that suckers do not live in muddy, silty water. Most suckers require very clean substrate and cannot tolerate low dissolved oxygen levels.
Most suckers are moderately long-lived, with an average life expectancy of 8 to 15 years.
Life history and Behavior
Suckers become sexually mature at 2-3 years of age. Most spawn in early spring, although some species also spawn in early summer. Many large species make long migrations to the upper reaches of rivers to spawn. They may come from farther up the river or from neighboring lakes. These species spawn upstream, then the larvae hatch and drift downstream, colonizing the lower reaches of the river. Spawning suckers typically require clean gravel substrate. Such habitats are usually found in the tailwaters of reservoirs, in riffles, and in gravel bars. Most suckers spawn in large schools. Several males may spawn at the same time with the same female. Many spawn in groups of three when the female is accompanied by two smaller males. The males line up next to the female in a suitable spot in the riffle or tail of the pool. All three individuals are then shaken vigorously as the sperm and eggs are released. This shaking allows the fish to burrow into the substrate and bury the newly laid eggs. Only one species of sucker, the river redhorse (Moxostoma carinatum), actually prepares a nest like a trout, but many of them move a lot of gravel by digging in the stream bottom. Suckers produce many small eggs and provide little parental care.
Food and feeding habits
With their narrow mouths and large, fleshy lips, suckers are well adapted to feeding on the bottom of streams or lakes. Most species suck up substrate and sift out small invertebrates and other organic matter. Insects and worms are the most common foods, although some fish specialize in eating snails, vegetation, or crustaceans. Some species also feed on detritus and scrape algae from rocks. The most common and numerous are suckers that feed on detritus, such as the white sucker. Chubsuckers (genus Erimyzon) feed on plankton in the middle layers of the water. The real value of suckers is their ecological role. They use food resources such as snails, detritus and algae that would otherwise go largely unused. This allows them to play an important role in the ecosystems in which they live, recycling nutrients and resources that benefit other species.
|Conservation status||Least Concern|
|Life span, years||17|
|Maximum body weight, kg||2.7|
|Maximum length, cm||64|
|Sailing speed, m/s||No information|
|Threat to people||Edible|
|Way of eating||Bentophage|