Thats a real bummer but it is hard to keep those rascals out no matter what yah build. We set live traps around our perimeter about 300 foot out and catch them by the handfuls, we actually caught two in one trap at the same time the other night. Now granted we are on 50 acres so we do have alot of traveling predators coming through to use our pond. Have caught everyone so far though, have yet to lose a bird to em.