Attributes / relations provided by
♦ ¹Food Web Relationships of Northern Puget Sound and the Strait of Juan de Fuca : a Synthesis of the Available Knowledge, Charles A. Simenstad, Bruce S. Miller, Carl F. Nyblade, Kathleen Thornburgh, and Lewis J. Bledsoe, EPA-600 7-29-259 September 1979
♦ ²Alaska Wildlife Notebook Series, Alaska Department of Fish and Game
♦ ³An estimate of summer food consumption of six seabird species in Iceland, K. Lilliendahl and J. Solmundsson, ICES Journal of Marine Science, 54: 624–630. 1997