The pond keepers that I know of that used fishing
line successfully had their pond inbetween two
greenhouses - a case of how your pond is situated
makes the difference. Another pond keeper used
fishing line to block the only area that the heron was
able to land in his yard - probably was very small
and lots of trees and tall bushes.

The picture did open up for me this time!
You've got a pretty wide open space and a nice
big pond.
Forgot to add, when I reposted that herons will
stand on top of plant baskets that looks like will
go on your shelf there.

There is an electric fence out there called
The Pond Guardian Electric Pond Fence,
enter those words in www.froogle.com and
it will come up. It is designed to attach to rocks
and lay out over the water. The way your rocks
are set up it might not be too hard of a job to
do. You might take a look at it. It is pretty
pricey though.

Putting a dog electric fence around it might work
but the heron could glide in and land on a plant
basket. They've even been known to land and float
around like a duck (not very dignified but a hungry
heron is a desperate heron).

You could try some combination of fishing line
first, it would be cheap, at least and you might
hit on a combination that works.

The heron's habit is to land away from its target
and very slowly move up to it, so as to not scare
its prey. You've got a lot of landing room and approach
there to work with... but it can't hurt to try!

kathy :-)
www.blogfromtheblog.com