I live by Spicer,Mn I get hundreds each year,I put out some regular minnow traps, with these make sure the entrance hole is at the max legal size, Think its 1&1/2 inch, and home made mudbug traps. I set them in farm drainage ditches under roads on the downstream side of the culverts. I use no bait traps and baited,strange the baited get lots of the big black snails and few dads.
Of all he things I ever done I aint never had too much fun
Keeping America clean and beautiful is a one mans job."Mine" We all need that attitude