They can be called in northern MN, and I have done so no problem. However in this thick bush country there are too many variables that cause problems.
First Cougar I called in was near the Window Rock reservation in AZ many years ago. Watched it coming for a long way, like all cats they do goofy things.
Osky
I attended the cougar calling school of hard knocks in NW washington state... I just wonder how many I never saw. I'd have never seen one hang up this far away.
