Lon Rombough has graciously given permission to post his whole article from the North American Fruit Explorers Pomona quarterly.

Fighting Birds with Birds

by Lon Rombough
Pomona Fall 2009 Vol. XLII No. 4

If you have any fruit in your garden, it only SEEMS like every bird in the world is after the crop. The reality is that a very small percentage of bird species eat fruit. Many others eat weed and grass seeds, and a good number eat insects and other invertebrates. Do the right things and you can recruit some of those insect and seed eaters as helpers.There are many species of wrens in North America and these feisty little insect eaters are very useful allies. Wrens of most species are very territorial and will defend their nests against other birds vigorously. A blueberry grower put nest boxes for wrens at each corner of a one acre blueberry plot. That way, the wrens had overlapping territories over the whole acre. So long as the bird houses were in good shape, the blueberries were protected by the little birds who would fiercely drive off any other bird species that came into their territory. Their effectiveness was proven when a storm knocked down a birdhouse at one corner of the field. With no wren to guard that area, the fruit eating birds moved into that section. Once the house was repaired a wren moved back in and the other birds moved OUT.More than one species of wren can do the job, too. We have a small pond where a marsh wren nested in the cattails, and even though our blueberries were at least 200 feet away, because they were in the line of sight of the wren, that little bird went after the robins and jays enough to greatly reduce how many berries the thieves took.If you do enlist the wrens, put the houses up high so they will be able to see a larger area and "claim" it as their territory. In an average city lot two houses should be enough to cover the whole yard, if they are placed correctly.Granted, using wrens works best when the wrens are nesting and raising young, but given the low cost of installing a few wren houses, the method is worth trying as it can help change the feeding patterns of the fruit eating birds, and some wrens may remain in residence long enough to help keep the fruit eaters out until youÂve harvested all your crop. And while they are there, they will be eating hundreds or thousands of insects that might otherwise feed on your other plants.Using wrens for helpers isnÂt a birdbrained idea.
Site for wren house plans http://www.50birds.com/mpb040806114.htm

Lon Rombough is very active in NAFEX and is the special consultant on grapes. He is involved with many other fruit related organizations and many kinds of fruit - including figs. He consults on fruit and has a lot of information available including videos, a book (The Grape Grower, winner of the Garden Writers Association "Best Talent in Writing" award for 2003) and a very interesting web site: http://www.bunchgrapes.com...