I put these out as a trial a few yrs. back & there was no snow at the time so due to that I wasn't sure if any Marten where in the area . I just picked what might be good spots to set . Lower flat area with fallen trees below a ridge , on top of a ridge & along a small raven . I discovered later after investigating area when snow did arrive there was no tracks what so ever . Already trapped out, Predator's , Disease . ? So I pulled out.