Observations on the Birds of Argentina, Paraguay, Uruguay, and Chile

ISBN: 9781331423577 出版年：2016 页码：475 Alexander Wetmore Forgotten Books

The successful operation of the Federal Migratory Bird Treaty in according protection, hitherto uncertain, to migratory game and insectivorous birds, with resultant increase in many species, led naturally to inquiries regarding the present status of birds that migrate in winter beyond our borders. Particularly was this the case with those species, mainly shore birds, that pass south into the southern portion of the South American Continent. To gather first hand information on the questions involved the Biological Survey, United States Department of Agriculture, in May, 1920, dispatched the writer to Argentina with instructions to carry on the desired observations. During the extended period of field work incident to such a task there was abundant opportunity to make representative collections of native birds and to record many points of interest concerning their distribution and habits.Since observation of shore birds was the main object in mind, travel was restricted largely to the level sections where suitable shores and marshes were available, so that collections were made in the main in the lowlands. The area covered extended from northern Paraguay south to northern Patagonia, and from the eastern border of Uruguay west to the foothills of the Andes in Mendoza, and included a limited section near Valparaiso, Chile. Points for work were chosen carefully to allow comprehensive survey of as large an area as practicable. Studies of the specimens secured together with field observations, where pertinent, are presented herewith in as much detail as is warranted.