Scientific assessments take these things into consideration, and that's the conclusion we reached for the southern gulf. After overfishing efforts that have reduced the stock's recovery capacity, grey seals seem to be the ones currently preventing the stock from recovering.
That's not the case in the northern gulf, however. Assessments are under way. Grey seals are much less present in this area. Analysis to date suggests that predation isn't the primary factor, and that environmental factors are more to blame. In the northern gulf, the cod population is doing very poorly, and current theories are that the phenomenon is related to mortality and environmental effects more so than predation.