INTRODUCTION 



This is the eleventh in a series of bulletins of the United States 

 National Museum on the life histories of North American birds. 

 Previous numbers have been issued as follows: 

 107. Life Histories of North American Diving Birds, August 1, 1919. 

 113. Life Histories of North American Gulls and Terns, August 27, 1921. 

 121. Life Histories of North American Petrels and Pelicans and their Allies, 



October 19, 1922. 

 126. Life Histories of North American Wild Fowl (part), May 25, 1923. 

 130. Life Histories of North American Wild Fowl (part), June 27, 1925. 

 135. Life Histories of North American Marsh Birds, March 11, 1927. 

 142. Life Histories of North American Shore Birds (pt. 1), December 31, 1927. 

 146. Life Histories of North American Shore Birds (pt. 2), March 24, 1929. 

 162. Life Histories of North American Gallinaceous Birds, May 25, 1932. 

 167. Life Histories of North American Birds of Prey (pt. 1), May 3, 1937. 



The same general plan has been followed, as explained in previous 

 bulletins, and the same sources of information have been utilized. 

 The nomenclature of the 1931 Check-List of the American Ornithol- 

 ogists' Union has been followed, but it has seemed best to continue 

 in the same order of arrangement of families and species as given in 

 the 1910 check-list. 



An attempt has been made to give as full a life history as possible 

 of the best-known subspecies of each species and to avoid duplication 

 by writing briefly of the others and giving only the characters of the 

 subspecies, its range, and any habits peculiar to it. In many cases 

 certain habits, probably common to the species as a whole, have been 

 recorded for only one subspecies; such habits are mentioned under the 

 subspecies on which the observations were made. The distribution 

 gives the range of the species as a whole, with only rough outlines of 

 the ranges of the subspecies, which in many eases cannot be accurately 

 denned. 



The egg dates are the condensed results of a mass of records taken 

 from the data in a large number of the best egg collections in the 

 country, as well as from contributed field notes and from a few pub- 

 lished sources. They indicate the dates on which eggs have been 

 actually found in various parts of the country, showing the earliest 

 and latest dates and the limits between which half the dates fall, the 

 height of the season. 



The plumages are described in only enough detail to enable the 

 reader to trace the sequence of molts and plumages from birth to 

 maturity and to recognize the birds in the different stages and at 

 the different seasons. No attempt has been made to describe fully 

 the adult plumages; this has been well done already in the many 

 manuals. The names of colors, when in quotation marks, are taken 

 from Ridg way's Color Standards and Nomenclature (1912), and the 



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