Black Hole Theory — Inner Space, Inner Warmth

The black hole theory of attracting wild songbirds to your garden and landscape states that birds cannot see anything in a birdhouse or nesting box to differentiate it from a natural cavity in a tree. When a hole is drilled into the face of the birdhouse, it appears from arm’s length or a considerable distance as a black hole. Except for the rough outlines of the cavity on a dead tree truck, its aspect is about the same as the hole in a birdhouse. Birds can see this black hole from a considerable distance and they are attracted to the hole for a nesting site, food, and winter protection. If you drilled a hole in a piece of wood and placed it on another piece of wood painted black, and hung it on a tree and had the patience to wait, in early spring, the birds would arrive.

Birdhouses, of course, are used only by a small number of songbirds, but that is reason enough to put them up as habitat for the wrens, chickadees, nuthatches, titmice, tree swallows, bluebirds, and downy woodpeckers. The natural range for these birds once was filled with many trees with deadwood in which woodpeckers chipped away an access hole to the soft and decayed interior and made a home. Today, without birdhouses to replace the natural habitat that is diminishing, the numbers of these species will likewise diminish.

Even if an abandoned woodpecker hole is available, a birdhouse is an advantage to the songbirds in that it has the added protection of a roof and a one and a half-inch hole that more perfectly fits the songbird species. Entrance holes to cavities in the wild would be much larger, as they have been carved out to fit a woodpecker's size.

The black hole or the entrance to a cavity that is a birdhouse intrigues birds throughout the year. After a barn feeder, the holes on many birdhouses are probably the next best attractant of feathered friends. Birds are curious. Cavities in nature attract. The absence of the real thing has put the humble birdhouse on a pedestal. Fortunately, with no government program here, homeowners have taken the responsibility of mounting birdhouses to offer birds a better cavity than found in the wild.

A black hole from 500 feet away is a strong draw for many birds the year around. In the cold winters of the Northeast, many birds find protection from zero degree temperatures if they can spot a black hole before nightfall. Many people have told me that they witnessed seven to eight birds leaving a birdhouse in the early morning after a cold evening.

The importance of the birdhouse for the above-named species cannot be overstated. Populations of these birds can only be maintained by duplicating (and even improving on) the natural cavity with a birdhouse. These cavities in yards and close to feeders assure the young of a better diet than is found in the wild—high protein seeds, carbohydrates, minerals and oils. Thus homeowners can bring about habitat conservation for wild songbirds in a short time.

The birds' confidence in an environment dominated by the interests of men can be increased by mounting birdhouses and their inviting entrance holes. I once had on a display rack about fifteen birdhouses facing into an open area. This was at a craft show, and the display was left overnight. In the morning, fellow crafters arriving early told us of the birds coming out of our houses. Obviously, that many black holes made a strong impression on the birds. They saw the holes from a wooded area 500 feet away.

The highly visible black hole in your birdhouse means the world to the bird for the reasons stated—nesting and protection. At zero degrees in January, the sight of a cavity access means his life to a wild bird. The black hole is home. It is a door to safety.