Well, not really. They both just scared the crap out of each other.
The Muskrat was just swimming aroung doing Muskrat stuff and the Heron was quite curious as to what was swimming through the water and went to take a look. When the Muskrat realized the Heron was there he turned tail pretty quick to head the other way. He gave the Heron a pretty good scare, and vice versa.
A shot of the Muskrat getting as far away from the Heron as possible.