Ptychocheilus lucius

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Ptychocheilus lucius
Captured Colorado Pikeminnov

Captured Colorado Pikeminnov

Systematics
without rank: Otophysa
Order : Carp-like (Cypriniformes)
Subordination : Carp fish-like (Cyprinoidei)
Family : White fish (Leuciscidae)
Genre : Ptychocheilus
Type : Ptychocheilus lucius
Scientific name
Ptychocheilus lucius
Girard , 1856

Ptychocheilus lucius ( English Colorado Pikeminnow, also Colorado Squawfish, Spanish Carpa Gigante del Colorado or Pez Squaw del Colorado) is the largestspecies of the genus Ptychocheilus nativeto North America.

description

Ptychocheilus lucius has an elongated, pike-like body shape. The conical, somewhat flattened head takes up almost a quarter of the body's length. Its color varies from a light olive green to slightly yellowish hues on the flanks and a silvery-white belly. Young fish have a dark spot on the caudal fin. The dorsal and anal fins each have nine fin rays. Colorado Pikeminnows can reach body lengths of up to 180 centimeters and are among the largest carp fish in the world. The largest Colorado Pikeminnow caught on a line came from the Colorado River and weighed 36.29 kilograms and was 152 centimeters long. Professional fishermen had caught specimens weighing over 45 kilograms from the Colorado River. Specimens caught in 1960 with a body length of 60 centimeters had an age of eleven years, in 1990 specimens caught were only 34 centimeters in length. The maximum age is estimated at 40 years.

distribution and habitat

Ptychocheilus lucius is endemic to the Colorado River in the southwestern United States . Together with fish species such as the bonytail chub ( Gila elegans ), humpback chub ( Gila cypha ) and razorback sucker ( Xyrauchen texanus ), it is one of the endangered fish species. Colorado Pikeminnow prefer to stay in the backwater of the turbulent, fast-flowing and murky rivers of the Colorado Basin. Adults prefer deep pools with sand or gravel. They are also found in the states of Arizona , California , Colorado , Nevada , New Mexico , Utah, and Wyoming , as well as in northern Mexico . Dams and habitat changes have shifted the range of the fish species to the upper reaches of the Colorado River and its tributaries such as the Green River , Gunnison River , White River, San Juan River and Yampa River . Was introduced Colorado pikeminnow in the Salt River and Verde River .

Way of life

Ptychocheilus lucius juveniles eat plankton and insect larvae and, at a length of 30 centimeters, become predatory fish that feed almost exclusively on prey fish. They reach sexual maturity at the age of five to seven years. The fish set out on extensive spawning migrations in spring and early summer. In the 1900s, Ptychocheilus lucius was still the top predator in the Colorado river system. According to stories, settlers caught particularly large specimens of this species of fish using mice, birds and small rabbits as bait.

use

The Colorado Pikeminnow was an important food fish of the native Indian population before its population declined sharply with the appearance of the first white settlers. It was also an important source of food for the first European settlers. One large specimen could support a whole family. They called it "White Salmon" because of its migratory behavior. In 1967 Ptychocheilus lucius was listed as a critically endangered species after its range and the density of the population declined sharply. In the 1960s the government applied the fish poison Rotenon to the Green River and San Juan River in order to destroy the native fish fauna and then to populate the river with sport fish such as rainbow trout or small bass .

Measures to protect stocks

In the habitat of Ptychocheilus lucius , fish ladders were built in to enable the species to spawn up and down the river. The introduction of non-native fish species is now heavily regulated in the USA. Progress in rebuilding the Colorado Pikeminnow population is still very little due to the high costs and conflicts with fishing tourism. Since the Colorado Pikeminnow today neither has a role as a food fish nor an important place as a sport fish, its protective measures are controversial.

Systematics

Ptychocheilus lucius belongs to the genus Ptychocheilus ; the species originated about 3 million years ago.

See also

literature

  • Lisa Kearsley: Guide to The San Juan River. Flagstaff, Arizona, Shiva Press, 2002.
  • William F. Sigler & John W. Sigler: Fishes of Utah. University of Utah Press, 1996, pp. 109-114.

Web links

Individual evidence

  1. ↑ a b c Ptychocheilus lucius on Fishbase.org (English)
  2. ↑ a b c d e Colorado Pikeminnow at Colorado River Recovery.
  3. ^ Fishing World Records
  4. ↑ C. David Vanicek and Robert H. Kramer: Life History of the Colorado Squawfish, Colorado pikeminnow, and the Colorado Chub, Gila robusta, in the Green River in Dinosaur National Monument, 1964-1966. Transactions of the American Fisheries Society, 98, pp. 193-208, 1969 ( abstract ).
  5. ↑ Mark Gard: Threatened fishes of the world: Ptychocheilus lucius Girard, 1856 (Cyprinidae). Environmental Biology of Fishes, 49, 3, p. 292, 1997 doi: 10.1023 / A: 1007352706376 (English).