The Cape whitefish or Berg-Breede River whitefish (''Cheilobarbus capensis'') is a

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fish or actinopterygians, is a class of bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built fins made of webbings of sk ...

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Cyprinidae Cyprinidae is a family of freshwater fish commonly called the carp or minnow family, including the carps, the true minnows, and their relatives the barbs and barbels, among others. Cyprinidae is the largest and most diverse fish family, and t ...

. It was formerly placed with the South African redfins in ''

Pseudobarbus ''Pseudobarbus'' is a ray-finned fish genus in the family Cyprinidae. The type species is Burchell's redfin (''P. burchelli''). The scientific name is derived from the Ancient Greek ''pseudes'' ("false") and the Latin word ''barbus'' ("beard", i ...

''. It is

tetraploid Polyploidy is a condition in which the cells of an organism have more than two paired sets of ( homologous) chromosomes. Most species whose cells have nuclei (eukaryotes) are diploid, meaning they have two complete sets of chromosomes, one fro ...

. Its closest living relative is the sawfin (''C. serra'').

Distribution and ecology

The Cape whitefish is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to the

Western Cape Province The Western Cape ( ; , ) is a province of South Africa, situated on the south-western coast of the country. It is the fourth largest of the nine provinces with an area of , and the third most populous, with an estimated 7 million inhabi ...

of South Africa, where it occurs in the

Breede River The Breede River (), also known as Breë River, is a river in the Western Cape Province of South Africa. Travelling inland north from the city of Cape Town, the river runs in a west to east direction. The surrounding western mountains formed th ...

's Brandvlei Dam and Sanddrift Dam, as well as the Hex River. Formerly, it was also found in and around the Berg River, but it seems to have disappeared from there. Populations have also been transplanted to

farm A farm (also called an agricultural holding) is an area of land that is devoted primarily to agricultural processes with the primary objective of producing food and other crops; it is the basic facility in food production. The name is used fo ...

water catchments, but it is not well known if these have thrived or failed.Impson & Swartz (2007) It inhabits the deeper stretches of rivers with rocky shores or

riparian A riparian zone or riparian area is the interface between land and a river or stream. In some regions, the terms riparian woodland, riparian forest, riparian buffer zone, riparian corridor, and riparian strip are used to characterize a ripar ...

trees. While young fish are common in

riffle A riffle is a shallow landform in a flowing channel. Colloquially, it is a shallow place in a river where water flows quickly past rocks. However, in geology a riffle has specific characteristics. Topographic, sedimentary and hydraulic indica ...

s, adults are not

rheophilic A rheophile is an animal that prefers to live in fast-moving water. Examples of rheophilic animals Insects *Many aquatic insects living in riffles require current to survive. *'' Epeorus sylvicola'', a rheophilic mayfly species ( Ephemeroptera ...

and will thrive in slow-moving water. Young fish are

carnivore A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant Plants are the eukaryotes that form the Kingdom (biology), kingdom Plantae; they ar ...

s, eating

zooplankton Zooplankton are the heterotrophic component of the planktonic community (the " zoo-" prefix comes from ), having to consume other organisms to thrive. Plankton are aquatic organisms that are unable to swim effectively against currents. Consequent ...

and small aquatic

invertebrate Invertebrates are animals that neither develop nor retain a vertebral column (commonly known as a ''spine'' or ''backbone''), which evolved from the notochord. It is a paraphyletic grouping including all animals excluding the chordata, chordate s ...

s. Adults have more

omnivorous An omnivore () is an animal that regularly consumes significant quantities of both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize ...

diets that consist of

benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from the Ancient Greek word (), meaning "the depths". ...

invertebrates and

alga Algae ( , ; : alga ) is an informal term for any organisms of a large and diverse group of photosynthetic organisms that are not plants, and includes species from multiple distinct clades. Such organisms range from unicellular microalgae, suc ...

e. The breeding season is in late spring (about October) when the water has warmed to above .

School A school is the educational institution (and, in the case of in-person learning, the Educational architecture, building) designed to provide learning environments for the teaching of students, usually under the direction of teachers. Most co ...

s of adults form to migrate to riffles with over one meter/yard deep water and

spawn Spawn or spawning may refer to: * Spawning, the eggs and sperm of aquatic animals Arts, entertainment and media * Spawn (character), a fictional character in the comic series of the same name and in the associated franchise ** ''Spawn: Armageddon' ...

in the late hours of morning. A good-sized adult female produces about 100,000 eggs. In

dam A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, aqua ...

s, it will use rocky and

gravel Gravel () is a loose aggregation of rock fragments. Gravel occurs naturally on Earth as a result of sedimentation, sedimentary and erosion, erosive geological processes; it is also produced in large quantities commercially as crushed stone. Gr ...

ly substrate in the shallows as a spawning place. The species is long-lived.

Status and conservation

This Cape whitefish is considered

Endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching, inv ...

by the

IUCN The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status ...

as it has declined much in recent decades. The main threat is the introduced

smallmouth bass The smallmouth bass (''Micropterus dolomieu'') is a species of freshwater fish in the Centrarchidae, sunfish family (biology), family (Centrarchidae) of the order (biology), order Centrarchiformes. It is the type species of its genus ''Micropterus ...

(''Micropterus dolomieu''), which has killed off the stocks of the fish in the Berg River

watershed Watershed may refer to: Hydrology * Drainage divide, the line that separates neighbouring drainage basins * Drainage basin, an area of land where surface water converges (North American usage) Music * Watershed Music Festival, an annual country ...

by eating juveniles. In Brandvlei Dam, where the barb's population is most healthy, the African catfish (''Clarias gariepinus'') is spreading; its impact will need to be assessed. The

common carp The common carp (''Cyprinus carpio''), also known as European carp, Eurasian carp, or simply carp, is a widespread freshwater fish of eutrophic waters in lakes and large rivers in Europe and Asia.Fishbase''Cyprinus carpio'' Linnaeus, 1758/ref>Ark ...

(''Cyprinus carpio'') and Mozambique tilapia (''Oreochromis mossambicus''), introduced for

aquaculture Aquaculture (less commonly spelled aquiculture), also known as aquafarming, is the controlled cultivation ("farming") of aquatic organisms such as fish, crustaceans, mollusks, algae and other organisms of value such as aquatic plants (e.g. Nelu ...

, are competing with the Cape whitefish for food.

Water pollution Water pollution (or aquatic pollution) is the contamination of Body of water, water bodies, with a negative impact on their uses. It is usually a result of human activities. Water bodies include lakes, rivers, oceans, aquifers, reservoirs and ...

is also a problem. It is also listed as endangered by the Nature Conservation Ordinance of

. For the time being, it may not be killed and only caught for supervised transfer trials to other

habitat In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ...

s. An initiative is aimed at restoring the stocks, so this large fish can be used in

fishing Fishing is the activity of trying to catch fish. Fish are often caught as wildlife from the natural environment (Freshwater ecosystem, freshwater or Marine ecosystem, marine), but may also be caught from Fish stocking, stocked Body of water, ...

and maybe

as an alternative to the harmful introduced species. There are many reasons as to why the population of the Cape whitefish have recently been declining, with human-related activity being one of them. A severe flood in 2008 as well as invasions of other predatory fish species are a likely cause of the decline as well. In order to prevent further decline, there are conservation actions in place such as managing non-native fish invasions as well as lessening the agricultural impact on aquatic habitat.

References

* {{Taxonbar, from=Q302487 Taxobox binomials not recognized by IUCN Freshwater fish of South Africa Fish described in 1841 Taxa named by Andrew Smith (zoologist) Taxonomy articles created by Polbot capensis