Siberian taimen
(Hucho taimen)
Image source: Jo's Animal Database
Classification
General data
Hucho taimen, the taimen, Siberian taimen, Siberian giant trout, or Siberian salmon, is a species of fish in the salmon family (family Salmonidae) of order Salmoniformes. These fish are found in rivers in Russia and adjacent regions.
The taimen is distributed from the Volga and Pechora River basins east to the Yana River in the north to the Amur River in the south.
On a larger scale, this includes parts of the Caspian and Arctic drainages in Eurasia and portions of the Pacific drainage in Mongolia and Russia (the Amur River).
In Mongolia, the taimen is found in both the Arctic and Pacific drainages, specifically the Yenisei/Selenga, the Lena, and the Amur River Basins. The taimen lives in flowing water and is only occasionally found in lakes, usually near the mouth of a tributary.
The taimen is not anadromous, but does show increased movement rates during the spawning season. The average home range size of taimen in the E.g.-Uur River of Mongolia is 23 kilometres (14 mi), but some tagged individuals show home ranges up to 93 kilometres (58 mi).
Coloration varies geographically, but is generally olive green on the head blending to reddish brown in the tail. Adipose, anal, and caudal fins are often dark red. The belly ranges from nearly white to dark gray.
The taimen appears to be the largest salmonid in the world, being heavier at average and maximum sizes than the largest North American salmonid, the chinook salmon. Most mature fish caught weigh from 15 to 30 kg (33 to 66 lb). The average length is from 70 to 120 cm (28 to 47 in). The maximum length is about 150 to 180 cm (59 to 71 in). The maximum size is not assured, but supposedly a fish caught in the Kotui River in Russia in 1943 with a length of 210 cm (83 in) and a weight of 105 kg (231 lb) is the largest size recorded. The IGFA world record is 45.80 kg (101.0 lb) with a length of 150.00 cm (59.06 in). It can reach at least 55 years of age.
Adult taimen are mainly piscivores, though they frequently eat terrestrial prey such as rodents and birds.