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
♦ ²Offshore diet of grey seals Halichoerus grypus near Sable Island, Canada, W. D. Bowen, G . D. Harrison, Mar. Ecol. Prog. Ser. 112: 1-11, 1994