Here's a few thoughts...
Medium Tech (Reflective tape): I observed the man who heads up the
Maryland organic growers putting up reflective mylar tape and asked if
it kept the birds out of his blueberries. I'll never forget the answer:
"It works great...at least until the berries get ripe."
Low Tech (Harrying birds): An elderly man in Colorado, who had worked
in ag around the world, suggested putting wren houses at each corner of
my half acre blueberry patch. His theory was that the fiesty little
wrens would drive off the big fruit eaters. I mounted the boxes, and
never noticed fruit-eating birds for years. However, this season the
fruit eaters started heavily working the patch. Too late I noticed two
of the houses had blown down and there were no wrens in the other two.
Rest assured the houses will be in tip-top shape next spring at nesting
High Tech (Electronic bird distress calls): This URL
<http://www.wildlife-control.com/> will bring up a website that
describes various broadcasting speaker devices that so upset the birds
they just leave. It's an expensive route, but they've got a lot of
testimonials that their screecher is highly effective. However, it is
not for me because my patch is too close to the house and I prefer
singing birds to death cries.