Smaller sculpins are quite commonly eaten by larger individuals in this highly cannibalistic species. Eggs are also cannibalized during the breeding season. Sometimes used for bait by anglers in search of large Brown Trout. Males occupy cavities beneath rocks on the streambed, vigorously defending their burrows from any intruders. Their heads become jet black and their dorsal fins become outlined in reddish-orange.
Females swell with eggs.
Often looking as though they will burst, the outline of individual eggs may be seen through the tightly stretched abdominal wall. Males attract females to their burrows through a number of courtship behaviors. Eggs are deposited on the ceiling of the burrow and the female makes good her escape from the larger, and occasionally cannibalistic male. Males remain at their nest after breeding, fanning their eggs, aerating them, and keeping them free of silt. They defend their eggs against invertebrate predators and against their cannibalistic neighbors, and occasionally eat some of their own eggs.