The Pacific sleeper shark has a taste for giant Pacific octopus, as well as squids, Pacific salmon, and harbor porpoises.

There are at least 32 species of demon catshark including the white ghost catshark, the smalleye catshark, and the Iceland catshark. The slow-moving creatures grow up to 2 feet long and feed on squid and crustaceans as far as 7000 feet beneath the sea.