a lot of this kind of education focuses on 'grubs,' which are not as common by volume as plain old slugs. slugs are somewhat riskier if you prepare them incorrectly, and are kind of slimy and gross, but they will flood you with protein and nutrients if you have the will to eat them without reserve.

(http://www.autoadmit.com/thread.php?thread_id=5801561&forum_id=2/#49454681)

plain-colored brownish or beige-looking slugs common across the northern hemisphere are nontoxic and can be made safe to eat by cooking combined with the removal of the digestive and anogential structures. in a slug, those are located on the torso near the slug's head, which means you can usually just chop them near the 'mantle' (the raised portion on top of the slug behind the head) and cook the remaining portion.

there are different processing techniques involving salt water and so on, but those are mostly applicable if you want to cook and eat the entire slug (including the intestines) and need to purge its waste beforehand.

(http://www.autoadmit.com/thread.php?thread_id=5801561&forum_id=2/#49454768)