Bullhead are found in many of the feeder streams of the rivers in the west of Barnsley. It is widespread in the Upper Don catchment and quite dense populations are present in Cawthorne Dike and Silkstone Beck.
But these populations are at risk of predation by the invasive Signal Crayfish which is extending into these areas. It is expected that Signal Crayfish will densely populate all open water courses in the borough in years to come and threaten Bullhead populations.
The Bullhead is a small fish with a large mouth, large pectoral fins, prominent eyes and a wide, flattened head - giving it its name ‘Bullhead’. They are brownish in colour with mottling or barring and pale undersides.
Males are commonly 10cm in length, but can be up to 18cm. During the spawning period males become blacker in colour with a white-tipped dorsal fin. Females become plump but rarely grow to more than 10 cm long.
It is a bottom-living animal. It favours fast-flowing, clear, shallow water with a hard gravel substrate and is frequently found in the headwaters of upland streams. It also occurs in more lowland situations, in well-oxygenated water if there is sufficient cover. It is not found in badly polluted rivers.
The large pectoral fins enable Bullheads to hold their position in fast flowing water and they spend a large amount of their life under flat stones and rocks – often in competition with White-clawed Crayfish and Signal Crayfish
They emerge at dusk to feed on small, bottom-living insects and other animals, moving in short, sharp darts along the river bed. Bullheads often behave aggressively towards one another and competition for shelter and foraging space can be intense. In turn, they are vulnerable to a wide range of predators, particularly Brown Trout and Heron
Their spawning period is between February and June with males guarding the eggs until they hatch.
For further information on distribution, conservation and actions relating to Bullhead and other local priority fish species,follow the links below.
Bullhead, Cottus gobio
Local Priority Species
Bullhead is not listed as a UKBAP priority species or as a Species of Principal Importance
However Bullhead is listed in Annex 2 of the EU Habitats Directive as a species of Europe interest from a conservation point of view.
Running water: rivers & streams