Geography
In the western U.S., the purple martin nests in abandoned tree cavities, such as old woodpecker holes or in opening formed in cliffs.
Significance
The species in the eastern U.S. utilizes the hundreds of thousands of compartmentalized bird houses that landowners provide to attract the purple martin to their properties.
Materials
The female martin will choose what box to construct the nest in and then proceed to build it out of such items as feathers, twigs, paper, strips of bark and straw.
Function
The male's contribution to the nest will be in the form of some green leaves, which are believed to provide a degree of moisture to the nest once the eggs are laid.
Types
Purple martin houses come in different shapes and sizes, are made up of such materials as wood and aluminum, and can be mounted on long telescoping poles to keep the house well off the ground.
History
Purple martins will also build a nest in a hollowed out gourd, a practice which was first started by the Native Americans.