Nothing new under the sun...
http://www.trapperpredatorcaller.com/article-index/russian-fisherman-killed-by-beaver
A friend and I were fishing a small, wooded stream in the Wisconsin Driftless and a (I assume..) female beaver charged him down about a 30 foot length of stream. He turned tail and backed away and said that she made a beeping sound sort of like a factory forklift when she was chasing him away. I imagine she had young nearby or some such thing..