James, some countries have a feral dog problem. Some counties in North America have a feral dog problem. But you don't seriously believe that dogs have killed all the ground squirrels, rabbits and ptarmigan near Anchorage do you? First of all, there never have been rabbits in the Chugach foothills. Those are snowshoe hares, which have huge natural population fluctuations. Ptarmigan also cycle naturally. Ground squirrels have never been abundant in the front range, in my experience, and of course they hibernate for 6 months a year. All three species are still there.

You do realize that many dogs nowadays aren't much bigger than a cat? And most cats I know can back down a dog. Do you see lots of stray dogs in Anchorage? I don't, probably because most people obey the leash law, at least when they are around other people and pets. And Anchorage Animal Control actually picks up roaming dogs and at least some owners are fined. Anchorage doesn't even have a person assigned to pick up cats.