For the wild food crowd, grocery shopping begins when you leave the supermarket. On the other side of those automatic sliding doors is a diffuse (and free) marketplace filled with geese, berries, turtles, seaweed, deer, scallops and basically anything else you can digest. This Sunday marks the second annual Martha’s Vineyard Local Wild Food Challenge, and organizer and chef Bill Manson has imported the resourceful philosophy of the hunter-gatherer from his native New Zealand. The contest takes place at the Rod and Gun Club in Edgartown, beginning at 4 p.m.