Hey Nicky, I have a cottage in Huntsville (really close to orrilia), and I have never actually saw a bullfrog in my life, and I saw 3 this past weekend, 1 small, 1 big, 1 Huge, heh.
Maybe about the snakes cause when I was approching one in me canoe, I watched him eat a smaller frog, it was kinda neat to cause I havn't seen that before. I haven't noticed a decline in garter snakes though, however I live in Timmins(about 7 hours north of orillia).
But you never know, maybe we should bring a long a shoutgun next time we go out just to make sure we don't get overrun