Ynghylch

A small, strangely shaped fish, the bullhead (also known as the 'Miller's Thumb') has a very large head, relatively large fins and a tapering body. It lives on the bottom of fast, stony rivers and streams feeding on invertebrates, such as mayfly and caddisfly larvae, and the eggs of other fish. Spawning occurs between February and June: the eggs are laid underneath stones or in pits and the male guards and cares for them attentively.