As both herons and comorants eat primarily fish I very much doubt that
approach would work unless you set up a pond of sacrificial fish and
made it a bit more tempting than those you are trying to
preserve.....it's the fish they want....It has to be said when watching
herons around the lake at the place I used to work they tended to be
solo operators but I don't know if this is the norm - but might explain
why placing a fake heron sculpture also seems to work with a smaller
pond....but my guess is you'd need an awful lot of these around a
lake/loch....We're going up there just after christmas...now I can't
wait to interrogate the owner on his policy with this...along with an
estimate of how many fish he loses to herons and what the cost
implications are....and Yep, once I find out I will report back to
rec.ponds even if it isn't moderated....

Gill
rec.pond lurker since Nov 2003 and very occassional poster - don't have
a pond at the moment just a great interest in them