The European bullhead (''Cottus gobio'') is a freshwater

fish Fish are Aquatic animal, aquatic, craniate, gill-bearing animals that lack Limb (anatomy), limbs with Digit (anatomy), digits. Included in this definition are the living hagfish, lampreys, and Chondrichthyes, cartilaginous and bony fish as we ...

that is widely distributed in Europe, mainly in rivers. It is a member of the family

Cottidae The Cottidae are a family of fish in the superfamily Cottoidea, the sculpins. It is the largest sculpin family, with about 275 species in 70 genera.Kane, E. A. and T. E. Higham. (2012)Life in the flow lane: differences in pectoral fin morphology ...

, a type of

sculpin A sculpin is a type of fish that belongs to the superfamily Cottoidea in the order Scorpaeniformes.Kane, E. A. and T. E. Higham. (2012)Life in the flow lane: differences in pectoral fin morphology suggest transitions in station-holding demand ...

. It is also known as the miller's thumb, freshwater sculpin, common bullhead, and cob. The European bullhead is a small

demersal 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 ...

fish that lives both in cold, clear, fast-flowing small streams and in middle-sized rivers. It also occurs on gravelly shores of cold lakes. Further, it thrives in diluted brackish water of the Northern

Baltic Sea The Baltic Sea is an arm of the Atlantic Ocean that is enclosed by Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, Russia, Sweden and the North and Central European Plain. The sea stretches from 53°N to 66°N latitude and from ...

Description

Unsere Süßwasserfische (Tafel 11) (6102597595)

The bullhead has a large broad head and tapering body, large fins and a rounded tail. The eyes are located near the top of the head. To the distinction from the other freshwater

species found in Northern Europe, it can be told from the alpine bullhead ''Cottus poecilopus'' by the fact that the rays of its pelvic fins are of similar lengths while the first and last rays are longer in the alpine bullhead. It can be distinguished from the fourhorn sculpin by the fact that the dorsal and anal fins terminate close to the tail giving a short caudal peduncle. When it rests on the bottom, the pectoral fins flare out resembling wings. The bullhead is usually about long and is light brown mottled with darker colour. The pelvic fins are colourless and lack the stripes of the alpine bullhead.

Biology

Food items eaten by the bullhead include

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 ancient Greek, βένθος (bénthos), meaning " ...

insects,

crustaceans Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean g ...

and other

invertebrates Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordat ...

. It breeds in the spring. The male digs a shallow hollow in which batches of eggs are deposited by several females. He then guards the nest for the month or so that it takes for the eggs to hatch.

Systematics and distribution

The European bullhead, as treated above, is widespread over most of the subcontinent and in England, but absent from the southern

peninsula A peninsula (; ) is a landform that extends from a mainland and is surrounded by water on most, but not all of its borders. A peninsula is also sometimes defined as a piece of land bordered by water on three of its sides. Peninsulas exist on a ...

e and from Northern Scandinavia. It is not a single uniform

taxon In biology, a taxon ( back-formation from '' taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular n ...

, however, but composed of morphologically and genetically differentiated subunits. Some of those have been distinguished already long time ago as separate

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics ( morphology), but that can successfully interbreed. Not all specie ...

or species with their own names, while in practice they have still mostly been treated under the concept of ''Cottus gobio''. In 2005, Freyhof et al. suggested subdivision of the European ''Cottus gobio'' into fourteen distinct species, of which six had been described earlier and eight were newly described and named. *'' Cottus aturi'' - France (

Adour The Adour (; eu, Aturri; oc, Ador) is a river in southwestern France. It rises in High-Bigorre (Pyrenees), in the commune of Aspin-Aure, and flows into the Atlantic Ocean ( Bay of Biscay) near Bayonne. It is long, of which the uppermost ca. ...

) *''

Cottus duranii ''Cottus duranii'', the Dordogne sculpin or Chabot d’Auvergne, is a species of freshwater ray-finned fish belonging to the family Cottidae, the typical sculpins. It is found in France. It inhabits the Loire and Dordogne river drainages. It reac ...

'' - France (upper

Dordogne Dordogne ( , or ; ; oc, Dordonha ) is a large rural department in Southwestern France, with its prefecture in Périgueux. Located in the Nouvelle-Aquitaine region roughly half-way between the Loire Valley and the Pyrenees, it is named ...

Loire The Loire (, also ; ; oc, Léger, ; la, Liger) is the longest river in France and the 171st longest in the world. With a length of , it drains , more than a fifth of France's land, while its average discharge is only half that of the Rhôn ...

etc.) *''

Cottus gobio The European bullhead (''Cottus gobio'') is a freshwater fish that is widely distributed in Europe, mainly in rivers. It is a member of the family Cottidae, a type of sculpin. It is also known as the miller's thumb, freshwater sculpin, common bu ...

'' sensu stricto - Germany, Sweden, Central Europe *'' Cottus haemusi'' - Bulgaria (

Beli Vit The Vit also Vid ( bg, Вит; la, Utus) is a river in central northern Bulgaria with a length of 188 km. It is a tributary of Danube. The source of the Vit is in Stara Planina, below Vezhen Peak at an altitude of 2,030 m, and it empties into ...

of Danube basin) *''

Cottus hispaniolensis ''Cottus hispaniolensis'' is a species of freshwater ray-finned fish belonging to the family Cottidae, the typical sculpins. It is found in France and Spain. It inhabits the Garonne river drainage. It reaches a maximum length of 10.5 cm. It ...

'' - France, Spain (

Garonne The Garonne (, also , ; Occitan, Catalan, Basque, and es, Garona, ; la, Garumna or ) is a river of southwest France and northern Spain. It flows from the central Spanish Pyrenees to the Gironde estuary at the French port of Bordeaux – ...

) *''

Cottus koshewnikowi ''Cottus koshewnikowi'', Koshewnikow's sculpin, is a species of freshwater ray-finned fish belonging to the family Cottidae, the typical sculpins. It inhabits the upper Volga drainage and northern and eastern Gulf of Bothnia from Estonia eastward ...

'' - Northeast Europe *'' Cottus metae'' - Danube drainage (

Sava The Sava (; , ; sr-cyr, Сава, hu, Száva) is a river in Central and Southeast Europe, a right-bank and the longest tributary of the Danube. It flows through Slovenia, Croatia and along its border with Bosnia and Herzegovina, and finally t ...

) *'' Cottus microstomus'' - East Central Europe: Poland, Slovakia, Ukraine etc. *''

Cottus perifretum ''Cottus perifretum'', the bullhead or miller’s thumb, is a species of freshwater ray-finned fish belonging to the family Cottidae, the typical sculpins. It is found on both sides of the English Channel, native to Great Britain. It also inhabits ...

'' - Great Britain, Netherlands, Germany, France *''

Cottus petiti ''Cottus petiti'', also called the ''chabot du Lez'' in French, is a species of freshwater sculpin, a fish in the family Cottidae. It is endemic to France, found only in a small 3 km stretch of the river Lez in Southern France near Montpe ...

'' - France ( Lez) *'' Cottus rhenanus'' - Netherlands, Germany *''

Cottus rondeleti ''Cottus rondeleti'' is a species of freshwater ray-finned fish belonging to the family Cottidae, the typical sculpins. This species is endemic to the coastal Hérault drainage of Southern France. The total known distribution comprises three ...

'' - France (

Hérault Hérault (; oc, Erau, ) is a department of the region of Occitania, Southern France. Named after the Hérault River, its prefecture is Montpellier. It had a population of 1,175,623 in 2019.Cottus scaturigo'' - Italy (Trieste, local) *'' Cottus transsilvaniae'' - Romania ( Argeș of Danube basin) For instance, in this classification the British bullhead are ''

''. In common usage and by e.g. conservation authorities, they are still mostly treated as ''Cottus gobio''.Bullhead ''Cottus gobio''
The Wildlife Trusts ead March 2016/ref>

References

External links

* {{Authority control Cottus (fish) Freshwater fish of Europe Fish of Europe Fish described in 1758 Taxa named by Carl Linnaeus