Interesting idea. I was planning on buying two of the propane cannons. I can get timers for them so they are only going off during daylight hours that the cormorants would be present. The cormorants showed up in late November and early December but the ducks didn't show up until end of December/January so figured I could put the cannons up once the cormorant threat had passed. While it would be a lot of work, my lake is long and skinny so the twine idea can be done. I happen to already have a lot of steaks and a lot of twine on hand too. We flood an adjacent planted field for the ducks, so the twine wouldn't be an issue for them.