Clanwilliam Redfin
Encyclopedia
The Clanwilliam Redfin is a ray-finned fish species
in the family
Cyprinidae. It is placed in the "wastebin genus" Barbus
– the typical barbels and relatives – by default. But actually it is far less closely related to the typical barbels than to the South Africa
n redfins in Pseudobarbus
, and may well belong in the latter genus. Like Pseudobarbus but unlike most other Africa
n "barbs", it is tetraploid. Its closest living relative is probably the Twee River Redfin
(B. erubescens).
, where it occurs in the upper Olifants River and its tributaries – the Biedou, Boontjies, Boskloof, Breekkrans, Driehoeks, Dwars, Eselbank, Jan Dissels, Matijes, Noordhoeks, Oudste, Ratels, Rondegat, Thee and Tra Tra Rivers – near Clanwilliam and Keerom.
It inhabits the pools and shallower water in larger clear and slightly acidic mountain streams. They are insectivore
s, eating mainly small mayflies (Baetidae), non-biting midges (Chironomidae) and ant
s (Formicidae). The breeding season is lengthy and lasts most of the summer, from November to January. Schools of adults form to migrate to shallow pools with slow-moving water and spawn
between rocks and boulders, depositing the egg
s in crevices between these.
by the IUCN, mainly due to the adverse impact of the introduced Smallmouth Bass
(Micropterus dolomieu) on its population. The most drastic declines have been in the past, and though the species is still declining it is not doing so at an alarming rate; wherever the perch has not become established yet it is actually rather plentiful. Bluegill
s (Lepomis macrochirus) and Rainbow Trout
s (Oncorhynchus mykiss) are other introduced species
that are significant as predators of younger Clanwilliam Redfins. Tilapia sparrmanii is yet another introduced fish that has an adverse effect on the stocks of B. calidus, in its case due to competition for food. The other main threat is water pollution
and other forms of unsustainable water use. Particularly the conversion of riparian lands for citrus
plantation
s, with the resultant uninhibited runoff
of pesticide
s and fertilizer
s, is considered very harmful.
The Clanwilliam Redfin occurs in the Cederberg Wilderness Area and the Matjies River Nature Reserve, where it is at least safe from habitat destruction
. It is listed as Endangered by the Nature Conservation Ordinance of Western Cape Province. For the time being, it may not be killed or caught. The species is on display in public aquaria
of Cape Town
, Clanwilliam and Jonkershoek to educate the public on its conservation
needs.
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
in the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Cyprinidae. It is placed in the "wastebin genus" Barbus
Barbus
Barbus is a ray-finned fish genus in the family Cyprinidae. The type species of Barbus is the Common Barbel, first described as Cyprinus barbus and now named Barbus barbus...
– the typical barbels and relatives – by default. But actually it is far less closely related to the typical barbels than to the South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
n redfins in Pseudobarbus
Pseudobarbus
Pseudobarbus is a ray-finned fish genus in the family Cyprinidae. The type species is Burchell's Redfin . The scientific name is derived from the Ancient Greek pseudes and the Latin word barbus . This genus contains some of the South African redfins...
, and may well belong in the latter genus. Like Pseudobarbus but unlike most other Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
n "barbs", it is tetraploid. Its closest living relative is probably the Twee River Redfin
Twee River Redfin
The Twee River Redfin or simply Twee Redfin is a ray-finned fish species in the family Cyprinidae. It is placed in the "wastebin genus" Barbus – the typical barbels and relatives – by default...
(B. erubescens).
Distribution and ecology
It is endemic to the Western Cape Province of South AfricaSouth Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
, where it occurs in the upper Olifants River and its tributaries – the Biedou, Boontjies, Boskloof, Breekkrans, Driehoeks, Dwars, Eselbank, Jan Dissels, Matijes, Noordhoeks, Oudste, Ratels, Rondegat, Thee and Tra Tra Rivers – near Clanwilliam and Keerom.
It inhabits the pools and shallower water in larger clear and slightly acidic mountain streams. They are insectivore
Insectivore
An insectivore is a type of carnivore with a diet that consists chiefly of insects and similar small creatures. An alternate term is entomophage, which also refers to the human practice of eating insects....
s, eating mainly small mayflies (Baetidae), non-biting midges (Chironomidae) and ant
Ant
Ants are social insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from wasp-like ancestors in the mid-Cretaceous period between 110 and 130 million years ago and diversified after the rise of flowering plants. More than...
s (Formicidae). The breeding season is lengthy and lasts most of the summer, from November to January. Schools of adults form to migrate to shallow pools with slow-moving water and spawn
Spawn (biology)
Spawn refers to the eggs and sperm released or deposited, usually into water, by aquatic animals. As a verb, spawn refers to the process of releasing the eggs and sperm, also called spawning...
between rocks and boulders, depositing the egg
Egg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...
s in crevices between these.
Status and conservation
This species is considered VulnerableVulnerable species
On 30 January 2010, the IUCN Red List of Threatened Species identified 9694 Vulnerable species, subspecies and varieties, stocks and sub-populations.-References:...
by the IUCN, mainly due to the adverse impact of the introduced Smallmouth Bass
Smallmouth bass
The smallmouth bass is a species of freshwater fish in the sunfish family of the order Perciformes. It is the type species of its genus...
(Micropterus dolomieu) on its population. The most drastic declines have been in the past, and though the species is still declining it is not doing so at an alarming rate; wherever the perch has not become established yet it is actually rather plentiful. Bluegill
Bluegill
The Bluegill is a species of freshwater fish sometimes referred to as bream, brim, or copper nose. It is a member of the sunfish family Centrarchidae of the order Perciformes.-Range and distribution:...
s (Lepomis macrochirus) and Rainbow Trout
Rainbow trout
The rainbow trout is a species of salmonid native to tributaries of the Pacific Ocean in Asia and North America. The steelhead is a sea run rainbow trout usually returning to freshwater to spawn after 2 to 3 years at sea. In other words, rainbow trout and steelhead trout are the same species....
s (Oncorhynchus mykiss) are other introduced species
Introduced species
An introduced species — or neozoon, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its indigenous or native distributional range, and has arrived in an ecosystem or plant community by human activity, either deliberate or accidental...
that are significant as predators of younger Clanwilliam Redfins. Tilapia sparrmanii is yet another introduced fish that has an adverse effect on the stocks of B. calidus, in its case due to competition for food. The other main threat is water pollution
Water pollution
Water pollution is the contamination of water bodies . Water pollution occurs when pollutants are discharged directly or indirectly into water bodies without adequate treatment to remove harmful compounds....
and other forms of unsustainable water use. Particularly the conversion of riparian lands for citrus
Citrus
Citrus is a common term and genus of flowering plants in the rue family, Rutaceae. Citrus is believed to have originated in the part of Southeast Asia bordered by Northeastern India, Myanmar and the Yunnan province of China...
plantation
Plantation
A plantation is a long artificially established forest, farm or estate, where crops are grown for sale, often in distant markets rather than for local on-site consumption...
s, with the resultant uninhibited runoff
Surface runoff
Surface runoff is the water flow that occurs when soil is infiltrated to full capacity and excess water from rain, meltwater, or other sources flows over the land. This is a major component of the water cycle. Runoff that occurs on surfaces before reaching a channel is also called a nonpoint source...
of pesticide
Pesticide
Pesticides are substances or mixture of substances intended for preventing, destroying, repelling or mitigating any pest.A pesticide may be a chemical unicycle, biological agent , antimicrobial, disinfectant or device used against any pest...
s and fertilizer
Fertilizer
Fertilizer is any organic or inorganic material of natural or synthetic origin that is added to a soil to supply one or more plant nutrients essential to the growth of plants. A recent assessment found that about 40 to 60% of crop yields are attributable to commercial fertilizer use...
s, is considered very harmful.
The Clanwilliam Redfin occurs in the Cederberg Wilderness Area and the Matjies River Nature Reserve, where it is at least safe from habitat destruction
Habitat destruction
Habitat destruction is the process in which natural habitat is rendered functionally unable to support the species present. In this process, the organisms that previously used the site are displaced or destroyed, reducing biodiversity. Habitat destruction by human activity mainly for the purpose of...
. It is listed as Endangered by the Nature Conservation Ordinance of Western Cape Province. For the time being, it may not be killed or caught. The species is on display in public aquaria
Aquarium
An aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants...
of Cape Town
Cape Town
Cape Town is the second-most populous city in South Africa, and the provincial capital and primate city of the Western Cape. As the seat of the National Parliament, it is also the legislative capital of the country. It forms part of the City of Cape Town metropolitan municipality...
, Clanwilliam and Jonkershoek to educate the public on its conservation
Conservation biology
Conservation biology is the scientific study of the nature and status of Earth's biodiversity with the aim of protecting species, their habitats, and ecosystems from excessive rates of extinction...
needs.