Another bottom-dwelling species is the sculpin. Four species are found in the Great Lakes. Sculpins have no scales. Their main adaptation to living in streams is their shape. Broad and flat at the head, they taper into a narrow tail. The teardrop shape allows them to sit motionless, particularly in flowing streams. Pectoral fins are broad and stiff and aid in movement along the bottom. In streams inhabited by trout, sculpins are often a prey species. Fly fishermen often use sculpin imitations tied from hair and feathers.
Nests are normally made under rock edges. Some species lay eggs upside down with females depositing eggs on the rock overhanging a nesting site.