Right on dude. I liked it a lot. Looks like you all had fun.
Not sure if you're looking for some feedback but if you want to know what I think, here are a couple constructive things:
I noticed you had some nat sounds in the beginning and towards the end, but I'd have nat sounds going on throughout...maybe a yelp or whoohoo from one of the dudes. I think sound goes a long way in helping connect the viewer with whats happening. So keep on striving for more with that. If the audio sucks, maybe pick up a shotgun or some kind of lav. Make sure the auto gain is off on your camera. (not sure what you're working with)
Another thing (depending on how murky the water was), I'd prob do a couple more gopro underwater shots...mount it up with a pole and show the fight as the fish comes closer. Makes for good cut away shots too so there would be less jump cuts. Would of been cool to see that last one release. Lastly, the rack focus in the beginning to that stick was kind of weird. Either make it smoother or pick another shot. It didn't really flow and seemed like a mistake. Same with the dude who through the knife...have him redo his reaction if he was out of focus. I know, might take away from the moment, but we wouldn't know. Keep it up dude. Looking forward to seeing whats next.