My personal opinion is that even though the laws regarding air gun hunting are not clear, I believe that one may not use it as an excuse, and hunting must be done accordingly to the hunting laws and season regulations. But for example, in NY, Red squirrels are unprotected and may be hunted at any time without limit. Though Hunting License is required. If anyone plans to hunt with air gun, he should take Hunter Education Classes to obtain that license.
BTW, this thread belongs more to the Hunting Gate.