The blackfin cisco (''Coregonus nigripinnis'') was a North American

salmonid Salmonidae is a family of ray-finned fish that constitutes the only currently extant family in the order Salmoniformes . It includes salmon (both Atlantic and Pacific species), trout (both ocean-going and landlocked), chars, freshwater whitefis ...

fish in the freshwater whitefish sub-family Coregoninae. This silvery, deep-bodied fish with black

fins A fin is a thin component or appendage attached to a larger body or structure. Fins typically function as foils that produce lift or thrust, or provide the ability to steer or stabilize motion while traveling in water, air, or other fluids. Fin ...

, large eyes, a blunt

snout A snout is the protruding portion of an animal's face, consisting of its nose, mouth, and jaw. In many animals, the structure is called a muzzle, rostrum, or proboscis. The wet furless surface around the nostrils of the nose of many mammals is c ...

and a terminal mouth, was one of the largest forms of

ciscoes The ciscoes (or ''ciscos'') are salmonid fish that differ from other members of the genus in having upper and lower jaws of approximately equal length and high gill raker counts. These species have been the focus of much study recently, as rese ...

. The blackfin cisco used to inhabit the

Great Lakes The Great Lakes, also called the Great Lakes of North America, are a series of large interconnected freshwater lakes in the mid-east region of North America that connect to the Atlantic Ocean via the Saint Lawrence River. There are five lakes ...

of North America until recently, but has been reported to have gone

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

. The blackfin cisco is a member of the '' C. artedi'' complex, whose taxonomy has not yet been resolved, and it may not represent a valid species.

Taxonomy

The species was first mentioned by P.R. Hoy 1872, attributing Gill as the species authority, but Gill's manuscript was never published. The first valid description of this species is attributed to

James Wood Milner James is a common English language surname and given name: *James (name), the typically masculine first name James * James (surname), various people with the last name James James or James City may also refer to: People * King James (disambiguati ...

in 1874. The taxonomy of ''C. nigripinnis'', along with other ciscoes in the '' C. artedi'' complex, is unresolved. ''C. nigripinnis'' was recognized by W.N. Koelz in 1929 to consist of four subspecies, but he had difficulty distinguishing some specimens from '' C. kiyi''. The subspecies he named were ''C. n. nigripinnis'' in

Lake Huron Lake Huron ( ) is one of the five Great Lakes of North America. Hydrology, Hydrologically, it comprises the easterly portion of Lake Michigan–Huron, having the same surface elevation as Lake Michigan, to which it is connected by the , Strait ...

and

Lake Michigan Lake Michigan is one of the five Great Lakes of North America. It is the second-largest of the Great Lakes by volume () and the third-largest by surface area (), after Lake Superior and Lake Huron. To the east, its basin is conjoined with that o ...

, ''C. n. cyanopterus'' in

Lake Superior Lake Superior in central North America is the largest freshwater lake in the world by surface areaThe Caspian Sea is the largest lake, but is saline, not freshwater. and the third-largest by volume, holding 10% of the world's surface fresh wa ...

, ''C. n. prognathus'' in

Lake Ontario Lake Ontario is one of the five Great Lakes of North America. It is bounded on the north, west, and southwest by the Canadian province of Ontario, and on the south and east by the U.S. state of New York. The Canada–United States border sp ...

and ''C. n. regalis'' in

Lake Nipigon Lake Nipigon (; french: lac Nipigon; oj, Animbiigoo-zaaga'igan) is part of the Great Lakes drainage basin. It is the largest lake entirely within the boundaries of the Canadian province of Ontario. Etymology In the Jesuit Relations the lake is ...

. ''C. n. cyanopterus'' was later synonymized with '' C. zenithicus'', and ''C. n. prognathus'' was declared a ''

nomen dubium In binomial nomenclature, a ''nomen dubium'' (Latin for "doubtful name", plural ''nomina dubia'') is a scientific name that is of unknown or doubtful application. Zoology In case of a ''nomen dubium'' it may be impossible to determine whether a s ...

''. Specimens from inland lakes in central Canada are generally regarded to be ''C. artedi''. Turgeon and Bernatchez proposed in 2003 to merge several cisco species, including the blackfin cisco, into the taxon ''C. artedi

sensu lato ''Sensu'' is a Latin word meaning "in the sense of". It is used in a number of fields including biology, geology, linguistics, semiotics, and law. Commonly it refers to how strictly or loosely an expression is used in describing any particular co ...

''.

Description

It was a dark silvery color, with a dark green to black back, and pink or purple on the sides; the outer half of the fins was black. Blackfin ciscoes measured up to 510 mm (21 inches in length). Its preferred habitat was cold lakes at depths of up to 180 metres.

Decline

The decline of the species was largely caused by

overfishing Overfishing is the removal of a species of fish (i.e. fishing) from a body of water at a rate greater than that the species can replenish its population naturally (i.e. the overexploitation of the fishery's existing fish stock), resulting in th ...

, which occurred during the 1950s as the result of mismanagement in an unregulated fishery, and predation from the invading

sea lamprey The sea lamprey (''Petromyzon marinus'') is a parasitic lamprey native to the Northern Hemisphere. It is sometimes referred to as the "vampire fish". Description The sea lamprey has an eel-like body without paired fins. Its mouth is jawless, ro ...

. The introduced alewife (''Alosa pseudoharengus'') and

rainbow smelt The rainbow smelt (''Osmerus mordax'') is a North American species of fish of the family Osmeridae. Walleye, trout, and other larger fish prey on these smelt. The rainbow smelt prefer juvenile ciscoes, zooplankton such as calanoid copepods ('' L ...

(''Osmerus mordax'') were also aggressive predators of juveniles. Blackfin ciscoes were commercially fished until the early 1960s when declining stocks made the fishery uneconomic. Current threats to any remaining populations include commercial fishing, predation by rainbow smelt and interbreeding with

lake herring ''Coregonus artedi'', commonly known as the cisco, is a North American species of freshwater whitefish in the family Salmonidae. The number of species and definition of species limits in North American ciscoes is a matter of debate. Accordingly ...

(''Coregonus artedi''). The blackfin cisco was last seen in

in 1960 and in

in 1969. The last sighting of the previously-linked "''cyanopterus''" population was in 2006 in Long Lake near

Thunder Bay Thunder Bay is a city in and the seat of Thunder Bay District, Ontario, Canada. It is the most populous municipality in Northwestern Ontario and the second most populous (after Greater Sudbury) municipality in Northern Ontario; its population ...

. This species may still be

extant Extant is the opposite of the word extinct. It may refer to: * Extant hereditary titles * Extant literature, surviving literature, such as ''Beowulf'', the oldest extant manuscript written in English * Extant taxon, a taxon which is not extinct, ...

. The

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...

lists it as extinct in 1996. The

Committee on the Status of Endangered Wildlife in Canada The Committee on the Status of Endangered Wildlife in Canada (COSEWIC, French: Comité sur la situation des espèces en péril au Canada, COSEPAC) is an independent committee of wildlife experts and scientists whose "raison d'être is to identify s ...

listed it as

threatened Threatened species are any species (including animals, plants and fungi) which are vulnerable to endangerment in the near future. Species that are threatened are sometimes characterised by the population dynamics measure of ''critical depensat ...

in 1988 and as

data deficient A data deficient (DD) species is one which has been categorized by the International Union for Conservation of Nature (IUCN) as offering insufficient information for a proper assessment of conservation status to be made. This does not necessaril ...

in 2007, due to the uncertainty of its taxonomic status. Efforts are being made to consider reintroducing populations of cisco into the Great lakes, specifically Lake Michigan.

References

* {{Taxonbar, from=Q308081 Fish of North America becoming extinct since 1500 Fish described in 1874 Coregonus Fish of the Great Lakes Extinct animals of the United States