Suckers are cylindrical fish with a downward-pointing suckering mouth in the family Catostomidae, which is in the large suborder Cyprinoidea, which also includes minnows, carps, and loaches.
Most species in the sucker family occur in the Americas, over a range that extends from the boreal forest of North America through much of Central America. A few other species occur in eastern Siberia, and there is one isolated species in eastern China.
Suckers are distinguished from other members of the Cyprinoidea by aspects of their jaw structure, the presence of a single row of teeth in their pharynx, a lack of barbels, and their round, downward-pointing, fleshy-lipped, sucking mouth. Suckers generally have a cylindrical or slightly compressed body.
Most species of suckers occur in flowing waters, such as rivers and streams. Some species also occur in still waters such as lakes and large ponds, but suckers living in these habitats spawn in nearby rivers.
The largest species of suckers can attain a length of 6.6 ft (2 m), but most are much smaller than this. Male suckers are smaller than the females. Both sexes become relatively brightly colored during the breeding season.
The primary food of suckers are aquatic invertebrates, which are mostly hunted in the sediment. Suckers that live in lakes may also eat some aquatic vegetation. The larger species of suckers are of some economic importance as food fishes for humans, although their flesh is rather bony. Other, smaller species are important as forage species for larger, more valuable species of fishes.
There are approximately one hundred species of suckers. The common or white sucker (Catostomus commersoni ) is a widespread species throughout much of northern and central North America. This species has a round mouth, useful for feeding on its usual prey of bottom-dwelling insects, crustaceans, molluscs, and other invertebrates. The common sucker is a relatively large species, attaining a length of up to 10 in (45 cm), and a weight of 2.2 lb (1 kg). The common sucker is often found in lakes and ponds. These fish generally run up nearby streams to spawn in gravel beds in the springtime, but they sometimes lay their eggs in gravel along shallow lakeshores. Individuals of this species can live as long as 12 years.
The longnose or northern sucker (Catostomus catostomus ) is also widely distributed in northern North America, and it also occurs in eastern Siberia. The longnose sucker generally inhabits cooler waters and occurs in deeper lakes and larger rivers and streams than the common sucker. This species is exploited commercially on the Great Lakes and elsewhere, although it is not considered to be a high-value species of fish. Other species of suckers are more local in distribution, for example, the Sacramento sucker (C. occidentalis ) of northern California.
Both the bigmouth buffalo (Ictiobus cyprinellus ) and the smallmouth buffalo (I. bubalus ) are widely distributed in the eastern United States. These species have also been transplanted farther to the west to establish some sportfishing populations. These fish can attain a large size, exceeding 22 lb (10 kg) in some cases, and are commonly fished as food.
Bait fish —Small fish that are used as live bait to catch larger fish.
Forage fish —This refers to small fish that are eaten by larger, economically important fish.
The northern redhorse or redfin sucker (Moxostoma macrolepidotum ) occurs widely in central North America. The lake or northern chub (Couesius plumbeus ) is a small minnow-sized fish that occurs widely across northern North America. This is an important forage and bait fish. The lake chubsucker (Erimyzon sucetta ) occurs in the eastern United States, including Lake Saint Clair and Lake Erie.
Moyle, Peter B. and Joseph J. Cech. Fishes: An Introduction to Ichthyology. 5th ed. New Jersey: Prentice Hall, 2003.
Nelson, Joseph S. Fishes of the World. New Jersey: John Wiley & Sons, Inc., 2006.
Integrated Taxonomic Information System. “Scientific Name: Catostomidae.” May 11, 2006. <http://www.cbif.gc.ca/pls/itisca/taxastep?king = Animalia&p_action = containing&taxa = Catostomidae&p_format = &p_ifx = plglt&p_lang => (accessed November 27, 2006).