Factual error: The wolves in this movie must be some sort of mutant super wolf. North American Grey wolves are not lion sized killing machines. They are typically smaller, by weight, than an average German Shepherd.
Factual error: The river that Ottway jumps into is filled with water from snow runoff, and as such it is barely above freezing temperature. Under those conditions, most people might have a few minutes to live before hypothermia and death. When Ottway gets out of the river, he isn't even shivering.