An occasional nesting site for owls in a wood of many acres, an appropriate box or two for Sparrow Hawks in a waste tract or along a few hundred yards of woodside will invite us to visit these places more often and will provide a new zest to the visits. At the same time, we are but following nature’s way of balancing the wildlife. Nor will the smaller birds be seriously affected; there may be a tendency for many of them to move in a little closer toward our dwellings for increased safety.
A house for small owls and the Sparrow Hawk should follow the lines of the house illustrated in [Plate V], size of entrance and other dimensions being given in [Table I].
The Common House Finch
The several western and extreme southwestern forms of the native House Finch may, for our present purposes, be grouped with birds like the Robin and Phoebe which find such a number and variety of chance but suitable nesting sites that to provide still others may seem superfluous effort. And yet, to see the bright red of the Common House Finch and to hear his cheery song, say, in the heart of a city like Denver where one looks only for English Sparrows, is to be tempted to offer this citizen a more “desirable property” than the water-spout or other chance nook or cranny in which he may otherwise elect to build. The most successful is the open or semi-open type of nesting box, as shown in [Plate VI], Nos. 1 and 2.
Robin and Phoebe
These birds are not classed as bird-house tenants. When they nest in a building, it is nearly always a deserted human dwelling or some other structure made originally for man’s own use. In other words, the only sort of bird house at all likely to attract Robin or Phoebe would be one of cavern-like proportions in keeping with one type of natural site which both species favor, especially the Phoebe.
The architecture of most human dwellings is such that either Robin or Phoebe would find nesting-sites, as they often do, over windows, under porches, or about eaves. But birds are not very considerate of the human liking for cleanliness, and their nests therefore are often placed where we least desire them. To lessen that chance and to furnish nesting-sites when they do not otherwise occur on a given dwelling or outbuilding, the following suggestions for nesting shelves are offered. The idea of nesting shelves is not a new one, and experience shows that an effective nesting shelf may be of almost any description.
