Umm, considering Florida and other US states according to the wiki, are the places mentioned, that's not exactly an unattainable climate in other areas of North America..... The conditions available in Florida and other southern states are available in many more locations, maybe not year round but long enough for them to breed....
That was a silly point to make considering your own link kinda just gave me ammo to use to prove my point further :-P so thanks!
EDIT:Don't downvote me if you don't understand climate zones.. Only southern Florida is considered tropical, no other American State has a tropical zone, but yet other states have it banned so we now know that it's not constrained to the tropical zone. Which logically means, it's climate zone is available across most of the southern states....