Bird House Placement
Where you put your bird house is as important as its design and construction. Cavity-nesting birds are very particular about where they live. If you don't have the right habitat, the birds are not likely to find the house. You can modify your land to attract the birds you want to see by putting out a bird bath, planting fruit-bearing shrubs, including more trees or installing a pond with a waterfall.
Once you've matched up the light bird house with the appropriate habitat, you have to know where to put the nest box. Should you hang it from a tree limb, nail it to a fence or mount it on a pole or a tree trunk?
Most species require a fairly narrow range of heights for nest boxes. After checking the table in this brochure, pick a height that's convenient for you. After all, you will want to watch what goes on and keep the box clean. If you want to watch chickadees from your second floor window or deck, fifteen feet is reasonable but it's a lot easier to clean out a box at eye level.
Here are some tips on where to put bird houses:
Protection from Predators
- don't put bird houses near bird feeders.
- houses mounted on metal poles are less vulnerable to predators than houses nailed to tree trunks or hung from tree limbs.
- use no more than four small nest boxes or one large box per acre for any one species.
- put about 100 yards between bluebird boxes and 75 yards between swallow boxes. (If you have both species, pair the houses with one bluebird box 25 feet from a swallow box.)
- don't put more than one box in a tree unless the tree is extremely large or the boxes are for different species.
- if you have very hot summers, face the entrance holes of your boxes north or east to avoid overheating the box.
Nesting birds are extremely vulnerable to cats, as are fledglings and birds roosting for the night. Bell collars on cats offer birds little protection. Nailing a sheet metal guard or cone to a tree trunk is unsightly, but may deter less agile felines. Houses mounted on metal poles are the most difficult for predators to reach, especially if you smear the poles with a petroleum jelly and hot pepper mixture. The best deterrent is for owners to keep their cats inside whenever possible.
Pet dogs are a hazard to nestlings in the spring and summer. Don't let your dog run loose during nesting time.
Red squirrels, and sometimes gray squirrels, can become a serious menace to bird houses and the birds themselves. If you find your riest hole enlarged, chances are a red squirrel is the culprit. Once inside the box, squirrels make a meal of the eggs and young. Adding a predator guard made of sheet metal to the entrance hole is usually enough to keep squirrels out.
Raccoons and Opossums
Raccoons and opossums will stick their arms inside nest boxes and try to pull out the adult, young, and eggs. Adding a '/.,-inch thick predator guard to the bird house or an inverted cone to its pole support is a simple solution.
Snakes play an important part in the balance of nature. If you find one in your bird house, don't kill it. Snake-proof your house by putting it on a metal pole lathered with petroleum jelly or red cayenne pepper.
House Sparrows and Starlings
If you don't discourage them, these two nuisance species introduced from Europe will harass or kill cavity-nesting birds. Since house sparrows and starlings are not protected by law, you may destroy their nests. But remember, other birds are protected by law.
House wrens sometimes interfere with the nesting success of other birds by puncturing their eggs. But, unlike the house sparrow and starling, these birds are native to North America and are protected by law. Don't be tempted to intervene when wrens appear at your backyard birdhouse.
Many insects lay their eggs and pupate in bird houses. Inspect your bird houses for signs of gypsy moths, blow flies, wasps, ants, gnats and bees. Keep bees and wasps from attaching their nests by coating the inside of the roof with bar soap. In areas where gypsy moths abound, avoid placing boxes in oak trees, which the gypsy moths favor.
Pyrethrin and rotenone insecticides are recommended for killing fly larvae, bird lice and mites after birds have finished nesting for the season.