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. 59:81-124, 1954), but no information is available on annual productivity. Abert's Towhee is multibrooded, and therefore, the number of broods per season as well as nesting success and clutch-size contribute to productivity. My objectives were to describe the productivity of Abert's Towhee in 1980 and to quantify seasonal variation in length of nesting, a factor that affects productivity. I have documented elsewhere (Finch, Condor 85:355-359, 1983) the effects of changing rates of brood parasitism on the nesting success of Abert's Towhee.