Broad whitefish
Species of fish
From Wikipedia, the free encyclopedia
The broad whitefish (Coregonus nasus) is a freshwater whitefish species. Dark silvery in colour, and like a herring in its shape. Its distinctive features includes: a convex head, short gill rakers, and a mild overbite. It is found in the Arctic-draining streams, lakes, and rivers of far eastern Russia and North America. Its prey includes larval insects, snails, and shellfish. It is eaten by humans and brown bears.
| Broad whitefish | |
|---|---|
| |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Salmoniformes |
| Family: | Salmonidae |
| Genus: | Coregonus |
| Species: | C. nasus |
| Binomial name | |
| Coregonus nasus Pallas, 1776 | |
| Synonyms | |
|
Coregonus kennicotti Milner, 1883 | |
Description
The broad whitefish is a herring-shaped fish with a more compressed body and convex head than other whitefishes. It is iridescent, with a dark olive-brown back, silvery grey sides, and a whitish bottom.[2][3] Features that distinguish it from other species include a mild overbite and 18–25 short gill rakers.[2][3] The fins of adults are grey, while those of young fish are grey.[4] It reaches a maximum length of 70 centimetres (28 in), and a maximum weight of 16 kilograms (35 lb).[2]
Distribution and habitat
The broad whitefish is found in Arctic-draining basins in northern Eurasia and North America from the Pechora River to the Perry River. Most commonly inhabiting streams,[3] it is also found in lakes and estuaries with a salinity of less than 15 percent.[1] Fish from freshwater populations sometimes migrate to or through ocean waters, especially in the winter.[4] It is nerito-pelagic, meaning that it is found in inshore open water.[2] Throughout its range it is widespread and abundant, and there are no known threats to its survival,[1][3] though it could potentially be threatened by overfishing, habitat destruction caused by oil exploration, and alteration of rivers.[4] It has a number of genetically distinct forms in the various basins it occurs in.[5] It has been stocked successfully in Belgium and unsuccessfully in Latvia, Ukraine, Estonia, China.[2] An introduction has been made in Mining, Austria, where a rod and reel record fish was caught in 2002.[6]
Ecology
Recorded items in the broad whitefish's diet are chironomid midges, mosquito larvae, snails, bivalves, and crustaceans.[4] It migrates upstream to spawn, except in some estuaries. These migrations are difficult for it, and many individuals become heavily scarred from infestations, lampreys, and fishing nets.[7] It prefers streams with gravel bottoms, especially those with finer gravel, for spawning. After hatching, larval fish move downstream.[4] In Russia, spawning occurs between July and November in various populations.[2]
As food
This fish is commonly consumed by humans, especially on a subsistence basis, and its good-tasting flesh is sold fresh, smoked, or dried.[2][4] Also known as Chir, the broad whitefish is one of the species used in the Arctic Siberian dish stroganina.[8]
It is also eaten by brown bears, especially when their preferred salmon is not available.[9]
