haha my weiner dog does that, with small fish, in the creeks. Or if you are reeling one into the boat, she's been known to jump into the water to "help" bring it in...she's a little neurotic/OCD when it comes to fish.
The videos pretty cool, but it really irks me when people let they're dogs harrass wildlife. Plus since the guy didn't legally catch it and it sure seems like he's gonna keep that fish, which makes him a poacher. I just hope it wasn't a native fish!