The gravenche (''Coregonus hiemalis''), also known as the Lake Geneva whitefish or the little fera, is a presumably extinct freshwater fish from

Lake Geneva , image = Lake Geneva by Sentinel-2.jpg , caption = Satellite image , image_bathymetry = , caption_bathymetry = , location = Switzerland, France , coords = , lake_type = Glacial la ...

in Switzerland and

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan ar ...

Description

The gravenche was a species of

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, ...

(Coregoninae) that reached a length between .Christian Trépey
Corégone (Féra - Palée)
www.plongee-passion.ch The status of the gravenche is disputed because there are no specimens in museums. While Emile Dottrens described it as subspecies of the common whitefish ''

Coregonus lavaretus ''Coregonus lavaretus'' is a species of freshwater whitefish, in the family Salmonidae. It is the type species of its genus '' Coregonus''. There are widely different concepts about the delimitation of the species ''Coregonus lavaretus'' an ...

'' in 1958, other experts like

Maurice Kottelat Maurice Kottelat (born 16 July 1957 in Delémont, Switzerland ...

regarded it as a full species endemic to

Lake Geneva , image = Lake Geneva by Sentinel-2.jpg , caption = Satellite image , image_bathymetry = , caption_bathymetry = , location = Switzerland, France , coords = , lake_type = Glacial la ...

.Maurice Kottelat: ''European Freshwater Fisches. An heuristic checklist of the freshwater fishes of Europe (exclusive of former USSR), with an introduction for non - systematists and comments on nomenclature and conservation''; Biologia: Section Zoology vol. 52/5, Slovak Academic Press, Bratislava 1997, Kottelat, M. & Freyhof, J. (2007). Handbook of European Freshwater Fishes. Cornol & Berlin: Kottelat & Freyhof.

Biology

The gravenche is a

benthopelagic The demersal zone is the part of the sea or ocean (or deep lake) consisting of the part of the water column near to (and significantly affected by) the seabed and the benthos. The demersal zone is just above the benthic zone and forms a layer o ...

freshwater fish Freshwater fish are those that spend some or all of their lives in fresh water, such as rivers and lakes, with a salinity of less than 1.05%. These environments differ from marine conditions in many ways, especially the difference in levels of s ...

that swam in the water column near the lake bottom, feeding upon

zooplankton Zooplankton are the animal component of the planktonic community ("zoo" comes from the Greek word for ''animal''). Plankton are aquatic organisms that are unable to swim effectively against currents, and consequently drift or are carried along by ...

Spawning Spawn is the eggs and sperm released or deposited into water by aquatic animals. As a verb, ''to spawn'' refers to the process of releasing the eggs and sperm, and the act of both sexes is called spawning. Most aquatic animals, except for aqua ...

occurred in mid-December.

Extinction

Together with the likewise extinct true fera (''Coregonus fera''), the gravenche was one of the most important species for fisheries in

Lake Geneva , image = Lake Geneva by Sentinel-2.jpg , caption = Satellite image , image_bathymetry = , caption_bathymetry = , location = Switzerland, France , coords = , lake_type = Glacial la ...

in the late 19th century. In 1890 these two fishes made up 68% of all fish caught in the lake.

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 the ...

and

eutrophication Eutrophication is the process by which an entire body of water, or parts of it, becomes progressively enriched with minerals and nutrients, particularly nitrogen and phosphorus. It has also been defined as "nutrient-induced increase in phytopla ...

drove the gravenche to near extinction and it was last seen in the early 1900s. Note: this source states that an introduced population of the gravenche, used for stockings, would still exist in the French Lake Aiguebette, in contrast to the IUCN account; this may represent confounding of information on different species.

References

External links

Catalog of Fishes Corregonus hiemalis
{{Taxonbar, from=Q1543946 Coregonus Fish described in 1825 Freshwater fish of Europe Lake fish Lake Geneva Cold water fish Extinct animals of Europe Fish extinctions since 1500 Species made extinct by human activities