Abstract. Among the bottom-living cephalopods, those able to dig into soft substrata show special behaviour patterns involving coordinated mantle/funnel, fin, and arm movements. This activity is triggered by light, and in the euphotic zone thus occurs at least once in a 24 h cycle. Effects of burial on the sediments are considered, drawing attention to the likely chemical side effects, especially relating to the mucus released by burying cephalopods. Persistent burrows are produced only by some octopuses. Their burial activities and the sand/mud digging of many squids and cuttlefishes are likely to play a notable role in bioturbation.