[2][3] The tidepool sculpin grows to a length of about 8 cm (3 in) and has a large head, tapering body, and spiny fins.

It has a single pre-opercular spine and tufts of cirri on the top of the head but not on the body below the dorsal fin as the fluffy sculpin (Oligocottus snyderi) does.

[7] The tidepool sculpin is a common small fish in pools in the intertidal zone of rocky coasts, flitting from one hiding place to another.

[4] It is a predator, feeding on small invertebrates such as isopods, amphipods, gastropod molluscs, polychaete worms and barnacles, as well as insects that happen to fall into the water.

It can leave the water and breathe air, exchanging both oxygen and carbon dioxide, while hiding in a damp spot, and it attempts to evade predators by flapping about or wriggling in an effort to reach a more favourable location.