Here's a possible way to figure out what it is...do you hunt ? if so, consider buying and setting up a Camtrakker (or similar type camera) pointing at some of your undisturbed cattails...if you don't hunt, most likely you've got a buddy that hunts and owns one of these cameras...I use them and they've taken some really interesting pic at the house..if you set it up, it shouldn't take long to see the culprit on film !...if you capture an image, please post...would be interesting...