We've seen gators in the lake by Shades of Green. They always seem to have a gator in that lake.

We've also encountered a few snakes. The first time was at CBR, there were several snakes swimming in the lake. We saw them while walking from the pirate room section to Old Port Royal just about every day. They appeared to be water moccasins, although we couldn't be 100% sure since we weren't close enough. I also know of a little boy who was bit by a water moccasin at CBR. He dropped his Buzz Lightyear toy near the landscaping at the bus stop. When he reached down to get it something bit him. His dad then saw the snake and called 911.

We also had a long, black snake in the pool at POR. We had just arrived in WDW. We had dinner at the foodcourt at POR, then went meet my SIL and her family at the pool. My kids were in the pool for a few minutes when we heard shouting about the snake. The CMs got the snake out and everyone continued swimming.