The broad whitefish (''Coregonus nasus'') is a

freshwater whitefish The freshwater whitefish are fishes of the subfamily Coregoninae, which contains whitefishes (both freshwater and anadromous) and ciscoes, and is one of three subfamilies in the salmon family Salmonidae. Apart from the subfamily Coregoninae, th ...

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

. Dark silvery in colour, and like a herring in its shape, its distinctive features include a convex head, short gill rakers, and a mild overbite. It is found in the Arctic-draining streams,

lake A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much large ...

s, and

river A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of w ...

s of far eastern

Russia Russia (, , ), or the Russian Federation, is a transcontinental country spanning Eastern Europe and Northern Asia. It is the largest country in the world, with its internationally recognised territory covering , and encompassing one-eig ...

and North America. Its prey includes larval insects, snails, and shellfish. It is eaten by humans and

brown bear The brown bear (''Ursus arctos'') is a large bear species found across Eurasia and North America. In North America, the populations of brown bears are called grizzly bears, while the subspecies that inhabits the Kodiak Islands of Alaska is ...

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.Froese and Pauly, 2010 Features that distinguish it from other species include a mild overbite and 18–25 short gill rakers. The fins of adults are grey, while those of young fish are grey.Alaska Natural Heritage Program, 2005 It reaches a maximum length of , and a maximum weight of .

Distribution and habitat

The broad whitefish is found in Arctic-draining basins in northern

Eurasia Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelago ...

and North America from the Pechora River to the Perry River. Most commonly inhabiting streams, it is also found in

s and

estuaries An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environmen ...

with a salinity of less than 15 percent. Fish from freshwater populations sometimes migrate to or through ocean waters, especially in the winter. It is nerito-pelagic, meaning that it is found in inshore open water. Throughout its range it is widespread and abundant, and there are no known threats to its survival,Page and Burr, 1991, p. 39 though it could potentially be threatened by overfishing,

habitat destruction Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...

caused by

oil exploration Hydrocarbon exploration (or oil and gas exploration) is the search by petroleum geologists and geophysicists for deposits of hydrocarbons, particularly petroleum and natural gas, in the Earth using petroleum geology. Exploration methods Vis ...

, and alteration of rivers. It has a number of genetically distinct forms in the various basins it occurs in. It has been stocked successfully in

Belgium Belgium, ; french: Belgique ; german: Belgien officially the Kingdom of Belgium, is a country in Northwestern Europe. The country is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeast, France to th ...

and unsuccessfully in Latvia,

Ukraine Ukraine ( uk, Україна, Ukraïna, ) is a country in Eastern Europe. It is the second-largest European country after Russia, which it borders to the east and northeast. Ukraine covers approximately . Prior to the ongoing Russian inv ...

Estonia Estonia, formally the Republic of Estonia, is a country by the Baltic Sea in Northern Europe. It is bordered to the north by the Gulf of Finland across from Finland, to the west by the sea across from Sweden, to the south by Latvia, a ...

, China. An introduction has been made in

Mining, Austria Mining (, as in ''mean-ing'', not as in ''mining'') is a municipality in the district of Braunau am Inn in the Austrian state of Upper Austria Upper Austria (german: Oberösterreich ; bar, Obaöstareich) is one of the nine states or of Austr ...

, where a rod and reel record fish was caught in 2002.

Ecology

Recorded items in the broad whitefish's diet are chironomid midges,

mosquito Mosquitoes (or mosquitos) are members of a group of almost 3,600 species of small flies within the family Culicidae (from the Latin ''culex'' meaning " gnat"). The word "mosquito" (formed by ''mosca'' and diminutive ''-ito'') is Spanish for "li ...

larvae,

snail A snail is, in loose terms, a shelled gastropod. The name is most often applied to land snails, terrestrial pulmonate gastropod molluscs. However, the common name ''snail'' is also used for most of the members of the molluscan class G ...

s, bivalves, and

crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can ...

s. It migrates upstream to spawn, except in some estuaries. These migrations are difficult for it, and many individuals become heavily scarred from infestations,

lamprey Lampreys (sometimes inaccurately called lamprey eels) are an ancient extant lineage of jawless fish of the order Petromyzontiformes , placed in the superclass Cyclostomata. The adult lamprey may be characterized by a toothed, funnel-like s ...

s, and fishing nets. It prefers streams with gravel bottoms, especially those with finer gravel, for spawning. After hatching, larval fish move downstream. In Russia, spawning occurs between July and November in various populations.

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. Also known as ''Chir'', the broad whitefish is one of the species used in the Arctic

Siberia Siberia ( ; rus, Сибирь, r=Sibir', p=sʲɪˈbʲirʲ, a=Ru-Сибирь.ogg) is an extensive region, geographical region, constituting all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has been a ...

n dish

stroganina 300px, Prepared ''stroganina'' on a table ''Stroganina'' ( Russian строганина, literally "shavings") is a dish of the northern Russians and indigenous people of northern Arctic Siberia consisting of raw, thin, long-sliced frozen fish ...

. It is also eaten by

s, especially when their preferred

salmon Salmon () is the common name for several commercially important species of euryhaline ray-finned fish from the family Salmonidae, which are native to tributaries of the North Atlantic (genus ''Salmo'') and North Pacific (genus '' Oncorhy ...

is not available.Barker and Derocher, 2009

References

Literature cited

* Alaska Natural Heritage Program (2005)
"''Coregonus nasus.''"
''Fishes Tracking List and Status Reports''. Retrieved 10 February 2010. * Barker, Oliver E., and Derocher, Andrew E. (2009)
"Brown Bear (''Ursus arctos'') Predation of Broad Whitefish (''Coregonus nasus'') in the Mackenzie Delta Region, Northwest Territories."
''Arctic'' 62(3):312–316. Retrieved 15 February 2010. * * * Harris, Les N. (2008)
"Population genetic structure of North American broad whitefish, Coregonus nasus (Pallas), with emphasis on the Mackenzie River system".
Dissertation for the Degree of Master of Science. Retrieved 12 February 2010 * Machacek, Heinz
"Fishing World Records"
''Fishing World Records.'' Retrieved 18 February 2010. * Page, Lawrence M., and Burr, Brooks M. (1991). ''A Field Guide to Freshwater Fishes'' Boston: Houghton Mifflin. * Reist, J. D.; R. A. Bodaly, R. J. P. Fudge, K. J. Cash, and T. V. Stevens (1987). "External scarring of whitefish, Coregonus nasus and C. clupeaformis complex, from the western Northwest Territories, Canada". ''Canadian Journal of Zoology'' 65(5): 1230–1239. .

External links

* {{Taxonbar, from=Q510354 Freshwater fish of the Arctic Coregonus Fish described in 1776