Tribal fishing cops? That's the best oxymoron I've heard. It doesn't seem like enforcement exists.

A longtime buddy of mine grew up on a well known local river often abused by netting. As kids, they would often throw hay bales in the rivers. Hay bales submerge, but will not sink, and absorb about 300 lbs of water with neutral bouyancy. He says this can take out every net in the river. I don't condone this, but it sure made a great story.