It’s a channel run in a creek, right where the run goes under the bank. 330. I’ve got a drowner set at the bottom of a slide as well, however they haven’t used it since we got a foot of snow about 5 days ago
Are you sure its not mink or rats as they often hug undercut banks and are noted for often springing 330 traps without getting caught. A 280 trap will solve the problem if that's the case.