I'd say the bears are already out, in fact i think i remember someone on here talking about how they saw one, but maybe i'm wrong.
The snakes i'm on the fence about, i'm not really sure. You can bet that if they are out now though, they will be perched up on top of a rock in the sunlight or somewhere that reflects heat right now until it warms up a little more.
Just a little something that i've found true: If you go out looking for snakes, then you'll find them. Sure, you'll run across one every now and then if you're not looking for them, i mean it's impossible not to crawling around in the woods like us fly fishermen do, but don't look for them.