Predation on seabirds by Pacific cod Gadus microcephalus near the Aleutian Islands, Alaska
In marine systems, most seabirds are considered upper trophic level consumers, yet they may be vulnerable to predation by other marine animals. There are varying accounts of large fish eating birds, but little is known about whether predation by demersal fish predators is an important source of mortality for seabirds. Fish processors in Dutch Harbor, Alaska, have observed seabird remains in Pacific Cod Gadus macrocephalus stomachs. We analyzed seabird remains from Pacific Cod caught off Cape Sarichef in Unimak Pass from mid-January through early April 2011. Of 74 different seabird remains examined, five avian genera were identified. These results provide documentation that Pacific Cod consume seabirds; either by predation or scavenging. Overall, the significance of seabird predation by fish is not well known, but may be episodically important.
Keywords: Pacific cod, predation, diet, Crested Auklet Aethia cristatella