Big Boy

It appears from the video that the rowers didn't notice the movement on the river bank. Understandably, they were focused on running the rapids, and the cameraman was focused on keeping the other boat in frame.

The location of the incident, and the physical appearance of the figure, and the behavior of the figure are consistent with a sasquatch. Nothing about the figure, or the incident in general, points to a hoax or a case of mistaken identity.

http://www.bfro.net/news/mckenzie.asp