When you have nothing but you and other wolfpacks at the top of the food chain, it is obvious what you will have to compete with. You might have a wolf die to a bear or something else every once in a while, but what else is there to even challenge a pack? Another pack, yes this makes sense. What if the pack of wolves in an area had to compete against a pack of mountain lions? The wolves would be in deep shit. You are showing that it depends on the area, so if the wolves are obviously at the top of the food chain in a certain area, they have no competition but themsleves. Humans only really compete with other humans, which is what I stated earlier. Wolves are not at the top of the food chain as far as social hunters go. Lions get killed by elephants in some places, and they aren't even predators.
What is going to fuck with an Orca (Killer Whale) other than a human? A Sperm Whale might be able to take one Orca down, but they can hunt as a family. Great Whites get eaten by Orcas. The only thing that kills an Orca with any regularity, is a human. Your greatest enemy is the species above you on the food chain that preys upon some of the same things you prey upon, if not then it is your species competing with itself. That is kinda common sense.