They are a big problem here too.
I've tried many legal way to keep them away from my pond, but they have been unsuccessful, more or less.
The only thing I've found successful is a sort of web made with some thick fishing line. Not a single cormorant in my pond since fall. They fly over my pond everyday but no one comes down.
The "web" is wide enough to fish through, 25/30 feet between lines, but crossed, so that the cormorants don't have enough free space to land and take off without hitting them. For this reason they don't feel safe and don't come.
I will remove the lines in May and put them back in early October.
