Bird Houses, Baths and Feeding Shelters: How to Make and Where to Place Them

by Edmund J. Sawyer

Although there are a number of points which should be considered in the proper designing and placing of a bird house, there is one simple idea which practically covers the whole subject. Every species of our small native birds that nests in a bird house nested originally in a hollow tree, by preference in a hollow of one unvarying type—the burrow made by a woodpecker. Thus we need only know what the burrow of a woodpecker is like and we have automatically solved in a general way the questions of material; size and shape of entrance; diameter, depth and form of cavity; height above ground; and situation. The nature of nesting material and its whereabouts should play absolutely no part in human plans for the prospective tenants. “Unfurnished” rooms are the only kind for which birds are looking.

There is solid ground for assuming a woodpecker’s burrow to be the ideal pattern for a bird house. The woodpecker, whatever its species, free to excavate any form of chamber that it might wish, invariably uses one type of burrow. The birds which by preference habitually adopt for their own use the woodpecker’s abandoned home have likewise thus placed their own age-old stamp of approval on that type. It is logical to assume, therefore, that the artificial bird house should follow at least the general plan of that long-tried and preeminently successful nesting site. Since a theory may be plausible while yet utterly untenable in actual application, it remains to add that abundance of experience in building and placing bird houses all goes to prove the foregoing basic principle soundly correct in practice. With or without benefit of the plans and specifications in such a bulletin as this, a person who takes his cue from a woodpecker will not go far wrong. In planning a bird house, we must continually hark back to the idea of the woodpecker’s burrow—or rather, we should never quite lose sight of it.

Some Current Notions Corrected

Attention should be called to some common misconceptions. The colony bird house, or any bird house with more than one compartment, is always a mistake unless it has been designed for Purple Martins. Yet certain firms have for years been advertising “wren houses” of four or more chambers. One who knows this pugnacious little bird tries in vain to imagine two pairs of wrens living peaceably under one small roof! Every bird house should consist of one, and only one, chamber—with the single exception of a house intended for the Purple Martin, which nests in colonies.

The cubic capacity of the bird houses one sees is nearly always much too great—often several times too great. Builders seem to believe that the diameter of the nesting chamber should at least equal the total length of the bird—a theory as erroneous as it is plausible. [Plate I] illustrates the fact that the sitting bird normally occupies a space measuring much less from side to side than the outstretched length of the bird. Figure No. 4, [Plate I], shows how much work is often made for the House Wren, while figure No. 5, on the same plate, shows how greatly this work may be reduced—with the greater inducement to the prospective occupant.

The square or rectangular door is another frequent mistake—a projection of the designer’s own plantigrade and vertical personality.

To place the entrance at or near floor level is also an error. Remember that birds close no doors against drafts, that their “beds” are laid on the floor and consist of light straws, feathers, or other flimsy materials.

Many a wren house with entrance (as it should be) too small for any English Sparrow to enter, is hung swinging from a branch as a further protection against the unwanted sparrow. That is like beheading a criminal and then, “just to be on the safe side,” shooting him into the bargain! It is said that wrens do not hesitate to use these swinging nesting sites, but we have our serious doubts. We have personally seen one instance of a wren nesting in the pensile home of a Baltimore Oriole, but it is significant that in this case we failed to find any better site nearby. Some persons report success with this type of house and prefer it because of the ease of putting it up and taking it down without injury to a living tree.

Two doors, presumably entrance and exit, to a bird house of one compartment is nearly as ridiculous an innovation as the two doors said to have been provided by a famous scientist for the use of his old cat and her kittens, respectively.