You know what their only natural predator is? Not wolves, but Killer whales.
Killer whales / Orcas are known as "wolves of the sea".
They aren't seen all that much in freshwater though, it is considered unusual.
https://www.seattletimes.com/seattle-news/orcas-make-rare-trip-into-fresh-water-in-alaska/
I wouldn't say your statement is accurate though with the "only" part. Wolves can easily kill caribou calves and sick/wounded adults. I don't think they will mess with healthy adults unless they can separate one from the herd.
No doubt the Orcas have the advantage when the Caribou are swimming though.
(post is archived)