As a young lad in the Arkansas boonies, I caught them with bacon on a paperclip tied to a string! Really! I never have seen one eat anything in the wild...
[url]http://www.uky.edu/Agriculture/Entomology/entfacts/trees/ef417.htm[/url]
There are about 100 species of crayfish in North America. Most are strictly aquatic but a few live in non-permanent water or semi-aquatic situations. They burrow into the soil to get to water when free water is not available on the surface. Some crayfish burrow into the soil even when surface water is available.
[url]http://www.mackers.com/crayfish/info.htm#behaviour[/url]
Crayfish, common in streams and lakes, often conceal themselves under rocks or logs. [b]They are most active at night, when they feed largely on snails, algae, insect larvae, worms, and tadpoles; some eat vegetation (various water plants). A dead fish, worms, corn, and salmon eggs are also favourites of the crayfish.[/b] Studies show that adults (one year old) become most active at dusk and continue heavy feeding activity until daybreak. Young crayfish are more likely to be the ones out during bright sunny days, while the older crayfish are more active on cloudy days and during the night. General movement is always a slow walk, but if startled, crayfish use rapid flips of their tail to swim backwards and escape danger.