I trap lots of beavers , all I go for is the front foot . the largest trap we can set is a bridger # 3 or sleepy creek # 4 . a hind foot will fill that up quickly . doesn't take anything bigger than a # 1 as long as your drowning rig is set up good . the snares are my preferred method . as long as they are in a watercourse you are legal . don't have to be submerged . set them up in pinch points or at bait or castor mounds . can't beat them .