I've got a buddy with a cabin on Moon Lake in Theresa, NY. We'll go up in December/January sometimes and there's a huge population of coyotes there. I've never seen it done but I'm told the locals will occasionally take a road-killed deer, chain it to a 5 gallon bucket and throw the bucket in one of the icefishing holes on the southwest side to freeze in. The carcass will draw the pack out onto the ice - giving the hunters a perfect shot from the nearby cliffs. That's one way to thin out a pack.