<a href=showthread.php?s=&postid=14953046#post14953046 target=_blank>Originally posted</a> by Ooulophilia
Look into a product called the "scarecrow" - I have put many in on koi ponds - it is basically a motion sensored sprinkler that sprays water in a rain bird pattern. It has worked for me in the past for raccoons, herons and egrets - you may need to put a few up but they are cheap and easy to install.