My children love animals, so while we were staying in Red Lodge, we spent about 90 minutes at the wildlife sanctuary.
While my review might only be average, I wanted to say that the work the Sanctuary does is fantastic. They are wonderful people doing much needed work to take care of animals in need. Some were surrendered by owners and some rescued in the wild.
The only reason I rated this as average was that it was difficult to see many of the animals, mainly because of the characteristics of the animals themselves. Some are nocturnal or just plain shy. So many times when we passed an exhibit for a mountain lion or other animal, we didn't see anything.
The bears were out and about, as were the wolves. They were very nice to see. My son and daughter loved the miniature horses and donkeys.
If you're not staying in Red Lodge, I'm not sure I'd recommend a long drive to visit, but if you're staying on the northern side of Yellowstone and didn't see a bear or wolf in the park, you can take the amazing drive on the Beartooth Highway over to Red Lodge and see both.