Head to head
European Bullhead vs Stone Loach
European Bullhead
VS Stone Loach
The European bullhead and the stone loach are two small, mottled bottom fish of clear, stony European streams, and lifting a flat stone in a river may reveal either one.
| European Bullhead | Stone Loach | |
|---|---|---|
| Scientific name | Cottus gobio | Barbatula barbatula |
| Group | A sculpin, a member of the family Cottidae | A loach, a bottom-dwelling relative of the carp family |
| Head and whiskers | A broad, flattened head and a wide mouth, with no barbels | Six sensitive barbels around the mouth, three on each side, used to detect food on the bottom |
| Body | A tapering body, mottled brown for camouflage on the stream bed | A long, nearly cylindrical, slimy body, olive-brown with dark mottling, and a rounded tail fin |
| Movement | Has no swim bladder, so it rests on the bottom and moves in short darts | Hides under stones, among weed, and in crevices during the day |
| Feeding | Ambushes insect larvae, shrimps, small crustaceans, and the eggs and young of other fish at dusk and at night | Feeds at night on insect larvae, small crustaceans, and other invertebrates among the stones |
| Breeding and company | The male prepares a nest under a stone and guards the eggs, which the female attaches to the roof of the nest, until they hatch | Lives in shoals or alone, depending on the stream, and is usually 8 to 12 cm long |
| Conservation status | Least Concern, but local populations are sensitive to pollution, and it is protected under European Union law | Least Concern, but sensitive to pollution and to the loss of clean gravelly streams |
European Bullhead vs Stone Loach: common questions
Which one has whiskers?
The stone loach, which has six sensitive barbels around its mouth, while the European bullhead has none.
Why does the bullhead stay on the bottom?
It has no swim bladder, so it rests on the bottom and moves in short darts rather than swimming continuously.
When do they feed?
Both hide by day under stones and feed in the dark, the bullhead hunting at dusk and at night and the stone loach coming out to feed at night.