My grandfather, a farmer in rural Virginia, was never much worried about saving endangered species or stopping climate change, or any environmental issue that didn’t directly impact next year’s soybean harvest. But as long as I can remember, he maintained a tiny apartment house on a pole in his back yard — just for purple martins.
Martins are glossy, deep-purple swallows that nest in big colonies. Originally, they used cavities in dead tree trunks and cliffs, but in eastern North America they’re now entirely dependent on human-made birdhouses like my grandfather’s. In a great video, Adam Cole of NPR’s Skunk Bear, talks to some martin landlords, discusses some of the challenges the birds face in modern times, and goes on an expedition to find one of the roosts where they gather in huge flocks before migrating to South America for the winter.