It was my first "stake out" of the season, and I lucked out. By pure chance, I was at the far end of the lower pond when the beavers came out of their lodge. At first there was one, then two, and at one point I had four in the shot, and a fifth did a tail slap about ten feet from where I was standing. I haven't seen any kits or activity in the upper pond yet.
Here's a five minute beaver ballet.