I've a favorite crossover I set for beaver-otter. Beginning of season I'll usually catch two animals in two days same crossover. But then, the other beavers seem to get wary and will not come close; so, I've learned to pull the 330, straighten everything up, slick up the crossover a little and wait. Usually after the next weathermaker i'll notice fresh sign then I'll set crossover again and...bam! Got another one. I let them dictate when to set, works for me! One other thing...once they get wise, beaver don't like two legged activity tramping around on the banks either.