The link below will take you the the North Atlantic Fisheries Organization (NAFO) site, where you can download the following papers:

Hammill, M. O. and G. B. Stenson.   Estimated Prey Consumption by Harp seals (Phoca groenlandica), Hooded seals (Cystophora cristata), Grey seals (Halichoerus grypus) and Harbour seals (Phoca vitulina) in Atlantic Canada.  in:   Journal of Northwest Atlantic Fishery Science - Volume 26 (2000).

* n.b. - almost all of the NAFO online documents are in PDF format - if you can't view PDFs....get with it.