A graph showing the relationship between the number of wolves and moose on Isle Royale since 1980. NPS. Wolf & Moose Population. The prey to predator relationship of Isle Royale's moose and wolves has a direct effect on both species' populations. Wolves help stabilize the moose herd by preying on the old, young, and ill, while strong moose numbers allow for stable winter hunting for the wolves. Check out the correlation between wolf and moose populations of Isle Royale since 1980.