Th Purple Martin (Progne subis), the largest swallow (Hirundinidae) that is widespread in North America north of Mexico, breeds commonly over much of the eastern U.S. and central Canada (Brown and Tarof 2013). Sparser and oftn isolated breeding populations are scattered through the Pacifi states (Kostka and McAllister 2005, Airola and Williams 2008) and southern British Columbia (Cousens et al. 2005), as well as the interior West from north-central Utah and western Colorado south to northern Mexico (Behle 1968, Doughty and Fergus 2002). Th location of reported breeding nearest to Idaho is about 35 km to the south in northern Utah, where Purple Martins nest mainly in abandoned woodpecker holes in mature aspen or mixed forests near water at high elevations (Hayward 1941, 1958, Brown and Tarof 2013).