A lot of people swear by chicken or turkey, but everything I have read on the subject, and my own experience shows fresh fish or other natural sea baits is a lot better. Last summer in the San Juans I dropped Chicken parts and fairly fresh slamon carcases in the same area, to test. The salmon won out with more and bigger crabs.

We usaully freeze salmon or steelhead carcases (after the filleting is done, of course) and that's what we usually use.