About purple martins (see Tuesday’s post, “gourds and cans”): they have become entirely dependent on humans for nests in which to breed along the North American east coast.
Susie at pbmGarden sent me the link to a short (about 8 mins.) NPR documentary about the songbirds and the threats they face in the modern world (the fault is partly in Shakespeare).
Check it out here: “The Mystery of the Missing Martins” by Adam Cole
enclos*ure 