Vertical distribution of pelagic cephalopods

The vertical distributions of pelagic cephalopods are analyzed, based primarily on sturlies undertaken in the waters off California, Bermuda, and Hawaii. Much of the information is derived from midwater trawl nets equipped with closing apparatus. Each family that contains pelagic or quasipelagic species is discussed; selected records from the Iiterature are inciuded where necessary. A wide variety of patterns of vertical distribution exists among pelagic cephalopods; patterns may be associated with stage of maturity, diel rhythms, or seasonal behavior. The study revealed that several basic types of vertical distributional patterns occur: near-surface dwellers, first order diel vertical migrators, second order diel vertical migrators, diel vertical shifters, diel vertical spreaders, nonmigrators, vertical wanderers, species associated with the ocean bottom, species exhibiting ontogenetic descent