Sculpin, bullhead, or sea scorpion, family of bottom-dwelling fishes (Cottidae) distinguished by a long body, large, wide head, and spiny gills and dorsal fin. Sculpins are found most often in the shallows of seas in northern regions. Bony and sometimes covered with spines, they have little food value, and sometimes steal bait and eat shrimp and young food fish. They are sometimes used as bait. The miller's thumb (Cottus goblo) is a common freshwater sculpin of Europe that grows to about 4 in (10 cm). The bullrout (Myoxocephalus scorpius) is a larger marine sculpin of Europe, North America, and the Arctic. The largest species grow to a length of 2 ft (60 cm).