The Banff longnose

dace A dace is a small fish that can be one of many different species. The unmodified name is usually a reference to the common dace (''Leuciscus leuciscus''). This, like most fish called "daces", belongs to the family Cyprinidae, mostly in subfamily ...

(''Rhinichthys cataractae smithi'') was a diminutive (about five cm. long) version of the eastern longnose dace, its range restricted to a small marsh fed by two hot springs on Sulphur Mountain in

Banff National Park Banff National Park is Canada's oldest national park, established in 1885 as Rocky Mountains Park. Located in Alberta's Rocky Mountains, west of Calgary, Banff encompasses of mountainous terrain, with many glaciers and ice fields, dense conif ...

Banff, Alberta Banff is a town within Banff National Park in Alberta, Canada. It is located in Alberta's Rockies along the Trans-Canada Highway, approximately west of Calgary and east of Lake Louise. At above Banff is the community with the second highest ...

. The development of a popular thermal swimming pool at the Cave and Basin eventually led to pollution of the dace's habitat. Deliberate introduction of

mosquitofish The western Mosquitofish (''Gambusia affinis'') is a North American freshwater fish, also known commonly, if ambiguously, as simply Mosquitofish or by its generic name, ''Gambusia'', or by the common name gambezi. Its sister species, the east ...

in the 1920s was followed by various tropical fish (and aquarium plants) which reproduce year-round in the marsh, while the Banff longnose dace only spawned once a year. The exotic fish also out-competed the dace for food and preyed on unhatched eggs. The few remaining Banff longnose dace hybridized with the Eastern longnose dace from the nearby Bow River. In 1981 a research study showed that the

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 ...

and the introduction of the non-native fish threatened the dace. It is hypothesized that this Banff subspecies' unique genetic structure was irreversibly mixed with another subspecies (termed introgressive hybridization), and by 1986 it had disappeared and was declared extinct in April 1987 by COSEWIC. Currently a study is underway to clarify the taxonomic classification of this putative subspecies.

References

Rhinichthys Fish of North America becoming extinct since 1500 Fish described in 1916 Endemic fauna of Alberta {{Leuciscinae-stub Endemic fauna of Canada

See also

References