Just got home from a trip to Wolf Park, near Lafayette, IN. It was "Howl Night". Got to see and hear a pack of 8 wolves howling in response to several more that were on the opposite side of a 4 acre lake. These wolves are tame enough that staff walked freely among them but they responded to the distant howling and would answer howls from the 30 or so people who attended. Lasted a little over an hour. It's an incredible sound! I'll go back and take grandkids.