Abert's Towhee (Pipilo aberti) is restricted to desert riparian zones of Arizona and bordering states (Phillips et al., The Birds of Arizona, Univ. Arizona Press, Tucson, Arizona, 1964). Its breeding behavior, communication, and physiological responses have been detailed by Marshall (Condor 62:49-64, 1960; pp. 620-622 in Proc. XIII Int. Omithol. Congr., Ithaca, New York, 1962; Condor 66:345-356, 1964), and Dawson (Univ. Calif. Publ. 2001.