Neighbors first suspected a human, but that's not possible considering the extent of the thievery. My next-door neighbor is convinced it's an otter or muskrat, but have you ever heard of a muskrat that can not only open the bait door, but also neatly close and strap the bungee cord back on?
Outdoors Girl suggests staying out of the water and away from those mini-piranha.
For an answer, she turned to a man of science, DNR critter czar Paul Peditto, for some clearheaded thinking. Peditto replied: River otter will invade pots to steal the live fish and crabs inside but they typically will leave a tell-tale clue (i.e., your trap will be bent where they wedged it open to grab their lunch). I suspect that is what's occurring here and the bait is then falling through the "otter opening." Reinforce the trap with some additional hog rings (available at your local hog-ring outlet store or nearby hardware/sporting goods retailer) and use whole fish (alewives are best) or larger bony chicken parts (necks/backs) rather than cutting up the fish/chicken into smaller chunks.
Muskrat will also eat small fish and crabs but are more likely seen eating grasses and sedges in our part of the world. They are also less likely to be the bad guys in this situation since they tend to be more passive than otters when it comes to finding chow.
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