PROTECTION FROM PREDATORS - Limiting Predator Access

Proper box depth, roof, and entrance hole design will help minimize predator (raccoons, cats, opossums, and red squirrels) access to birds living in your birdhouses. Sometimes all it takes is an angled roof with a three-inch overhang to discourage mammals.

The entrance hole is the only thing between a predator and a bird house full of nestlings. By itself, the 3/4" wall isn't wide enough to keep out the arm of a raccoon or house cat.  Add a predator guard a 3/4 inch thick rectangular wood block, to thicken the wall, and you'll discourage sparrows, starlings, and cats.

Cats  
Nesting birds are very 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 it may deter less agile felines.  Birdhouses 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.

Dogs
Pet dogs are a hazard to nestlings in the spring and summer.  All it takes is one swift bite and the baby bird is gone.  Don't let your dog run loose during nesting time.

Squirrels 
Red squirrels, and sometimes gray squirrels, can become a serious menace to bird houses and the birds themselves.  If you find your nest 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 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 predator guard to the bird house or to its pole support is a simple solution.

Snakes
Snakes are an important part of the natural balance between predator and prey.  If you find one of these reptiles in your bird house, please don't kill it.  Snake-proof your house by putting it on a metal pole lathered with a petroleum jelly or hot red cayenne pepper.

European Starlings and House Sparrows  
If you don't discourage them, these two pest species introduced from Europe will bully 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 house wrens interfere with the nesting success of other birds by puncturing their eggs.  But unlike the sparrow and starling, these birds are part of the natural system. They are protected by law.  Don't be tempted to intervene.

 


Insects
Many insects lay their eggs and pupate in bird houses. You should inspect your bird houses for signs of gypsy moths, blow flies, wasps, ants, gnats, and bees.  You can 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 are favored by the gypsy moths.

Pyrethrin and rotenone insecticides are recommended for killing fly larvae, bird lice, and mites.  Use only after the birds have finished nesting for the season.

I hope the information we have been providing in our blog has helped you to enjoy your bird watching.  Please feel free to add any tips or tidbits of information for our readers. If you have an interest in adding to your birdhouse or bird feeder collection, visit our website at www.aboutbirdhouses.com. 

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. No matter how perfect your bird house or nest box, if you don't have the right habitat, the birds aren't likely to find it.  Not everyone has the habitat for a wood duck, purple martin, or screech owl. On the other hand, just about anyone can attract a robin, titmouse, wren, or chickadee.

Let's assume you've built or bought the "perfect" birdhouse. You put it out in your backyard in February. Months pass, and not one bird has landed on it. What's wrong?   It may be that you don't have the right habitat, or it may be where you placed the birdhouse.

There are a lot of things you can do to modify your land to attract the birds you want to see.  It can be as simple as putting out a bird bath or as complicated as planting fruit-bearing shrubs or installing a pond with a waterfall.  But it's much easier just to identify the birds most likely to take to your backyard as it is and place the appropriate nest box in the right place.

Should you hang it from a tree limb, nail it to a fence, or mount it on a pole or a tree trunk?   There's a wide range between how high and low you can place a nest box. Pick a height that's convenient for you. After all, you'll 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 not unreasonable but it's a lot easier to clean out a box at eye level.

Here are some tips on where to put bird houses:
•    Birdhouses mounted on metal poles are less vulnerable to predators than birdhouses nailed to tree trunks or hung from tree limbs.
•    Use no more than four small nest boxes for any one species or one large box per acre.
•    Put about 100 yards between bluebird birdhouses and 75 yards between swallow boxes (if you have both species, "pair" the houses with one bluebird box 25 feet from a swallow box. Put the "pair" 100 yards away.)
•    Don't put bird houses near bird feeders.
•    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.
We hope this information helps you to enjoy the many different birds you will attract to your backyard.  When you have the time check out the many birdhouses and bird feeders we have available at our website www.aboutbirdhouses.com.