AROUND HOME : Building a Better Birdhouse

YOU DON’T HAVE to be a member of the Audubon Society to appreciate birds in your back yard; they eat bugs, they sing cheerfully, and their behavior is fascinating. But they don’t hang around without a good reason; food, shelter and protection from predators are the best reasons anyone can provide. Birdhouses and bird feeders are among the simplest constructions ever devised--no carpentry skills needed, no power tools, no expensive materials. Scrap lumber or even, in some cases, hollowed-out logs do nicely.

First you must figure out which birds you would like to encourage to stay. Birds are very finicky about accommodations, and if you hang out a huge gourd for hummingbirds, you’ll end up with jays. Purple martins--a bird seldom seen in Southern California--require an apartment building with at least six units with exactly 2 1/2-inch-diameter entry holes. Making one of these is difficult.

But a little square hut for a sparrow or a flat surface for feed is easy. It’s best to consult a bird book for exact dimensions if you are constructing a house for a specific bird. Feeders are much more generic: a floor with a lip or rim plus a roof equipped with a mechanism for hanging. Some of these feeders have bins from which the food flows slowly out the bottom as the birds eat it. There are also vertical tubes holding larger seeds and cages for suet. Whatever the structure you manufacture, take care that cats, squirrels and other animals can’t reach it. Feeders suspended from the eaves of a house, especially near a window, are safe, and they give the humans inside an enjoyable show. Birdhouses should be placed atop poles that are fitted with large inverted funnels to discourage climbing predators. One last caution: Be sure the bottom of the birdhouse is perfectly level or tilted slightly so that rain will not flow inside.

The Los Angeles Audubon Society, located in Plummer Park at 7377 Santa Monica Blvd., Hollywood, maintains a bookstore and offers advice on the proper care and feeding of back-yard birds.

“Songbirds in Your Garden,” by John K. Terres (Harper & Row/Perennial Library), has several suggestions for avian accommodations. “The Backyard Builder,” edited by John Warde (Rodale Press), contains instructions for a bin and flat feeder, suet holder and finch feeder. “Homemade: 101 Easy-to-Make Things for Your Garden, Home, or Farm,” by Ken Braren and Roger Griffith (Garden Way Publishing/Storey Communications), features five birdhouses and feeders. Also check “The Complete Book of Birdhouse Construction for Wood Workers,” by Scott D. Campbell (Dover Publications). “Homeowner’s Complete Outdoor Building Book,” by John Burton Brimer (Popular Science Publishing Co./Harper & Row), has instructions for several bird feeders and houses, plus a chart of dimensions required for various birds. Alas, it is out of print; search libraries and used-book stores. And the Jan./Feb. 1989 issue of Harrowsmith has several unusual birdhouse designs.