The Water Economy of Land Birds

Abstract

During the past decade we have, together with various colleagues, undertaken a series of studies surveying the water economy of ]and birds in order to gain some preliminary insights into the ways different species have reso]ved the problem of maintaining a water balance.A]though our studies have raised more questions than they have answered, they do a]]ow the establishment of appropriate ecological and physiological perspectives.The purpose of this review is to sum up the conc]nsions from exploratory studies, in the hope that they may serve as a guide to more sophisticated physiological experiments and for more quantitative and precise ecological analyses.Our point of view is primarily ecological, and we shall confine our remarks to wild species of ]and birds.Readers interested in the domestic fowl should consult Sturkie (1954), and those requiring a broader physiological coverage shou]d see Chew (1961).Histor{ca!summary.--Fewerthan a dozen publications bearing specifically on the water economy of wild birds appeared prior to 1950.Buxton (1923) broached the problem of the water re]ations of desert-inhabiting birds and mammals, and suggested that some species might depend upon metabolic water.A]len's (1925) semipopular treatment of arian biology contains a brief section on drinking habits, and Stresemann (1927) in his monumental treatment of birds for the Hand•uch der Zoo•o•{½ noted the general lack of information on avian water economy.Apparently as a ß A review article prepared at the invitation of the Research Committee of the American Ornithologists' Union.