Phoxocephalid Amphipod Crustaceans as Predators on Larvae and Juveniles in Marine Soft-Bottom Communities

Abstract

Feeding patterns of phoxocephalid amphipod crustaceans are explored from soft-bottom communities in Monterey Bay, California (USA), Kaikoura (New Zealand) and McMurdo Sound (Antarctica). Crop contents indicate that benthic invertebrates are major prey, especially soft-bodied nematodes and polychaetous annelids. Phoxocephalids also consume or trample larval and small juvenile polychaetes in laboratory and field feeding experimens. Gut contents of the numercially abundant infaunal species co-occurring with the phoxocephalids (primarily crustaceans and polychaetes) contain few or no invertebrate prey. Dietary patterns and feeding experiments are difficult to link to benthic community structure. Nevertheless, the phoxocephalids may play disproportionately important community roles by consuming settling larvae and juveniles of soft-bodied invertebrates.