There's a good chance. If you just take something like the grey seal population on the Scotian Shelf and figure out how much fish they would have to eat to survive, and then you look at DFO's own research vessel survey, you'd come out to about 50% of the total fish biomass observed in the survey being potentially consumed by the grey seal herd. If you go up to the Newfoundland region for harp seals, you're at about 25%. It is quite clear that the consumptive potential of those pinnipeds is quite dramatic and can impact those systems quite substantively.
Evidence of meeting #58 for Fisheries and Oceans in the 44th Parliament, 1st Session. (The original version is on Parliament’s site, as are the minutes.) The winning word was pinnipeds.
A recording is available from Parliament.