Purple Martins

The Nature Society
Recreation, Birding, Backyard Birding, Purple Martins - The Nature Society. A Purple Martin organization established in 1962.
http://www.naturesociety.org/
Purple Martin Preservation Alliance
Recreation, Birding, Backyard Birding, Purple Martins - Purple Martin Preservation Alliance. Devoted to the preservation and recovery of the Purple Martin through hands-on conservation projects, management of existing breeding sites, and research.
https://www.purple-martin.org/