Shortnose sucker

Shortnose sucker
Conservation status
Endangered  (IUCN 3.1)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Cypriniformes
Family:	Catostomidae
Genus:	Chasmistes
Species:	C. brevirostris
Binomial name
Chasmistes brevirostris Cope, 1879

The shortnose sucker (Chasmistes brevirostris), also known as the koptu (pronounced /ˈkɒp.tuː/ KOP-too) by the Klamath Tribes, is a rare species of fish in the family Catostomidae, the suckers. It is native to southern Oregon and northern California in the United States. This species and related ones were a major food source for local tribes, and are still considered to be sacred animals. It is a federally listed endangered species of the United States.

This fish can grow up to half a meter (1.6 ft) long. It has a large head and thin, fleshy lips, the lower of which is notched. It has been observed to reach 33 years of age. It becomes sexually mature between four and six years of age.

The preferable habitat for the fish is a turbid, shallow, somewhat alkaline, well-oxygenated lake that is cool, but not cold, in the summer season.

The fish usually spawns in flowing river habitat, such as riffles, with gravelly or rocky substrates. It was at one time observed to spawn at lakeshores, but it apparently does this rarely today. The eggs incubate for two weeks and the juveniles hatch between April and June. The juveniles generally stay along the shoreline in vegetated or unvegetated habitat.

Today this fish can be found in Upper Klamath Lake and its tributaries, the Lost River, Clear Lake, the Klamath River, and Gerber Reservoir of the Klamath Project.

Threats to this species include the reduction of its spawning habitat, much of which was eliminated by the construction of dams in local waterways. Upper Klamath Lake experiences periodic blooms of cyanobacteria and reduction of dissolved oxygen in the water. Land alteration along the waterways has caused loss and degradation of the habitat.