1939 



Lynch, J. J. 1939. Marine algae in food of Rhode Island waterfowl. Auk 56: 

 374-380. 



1937 



Benson, D. 1937. Studies in the ecology of the Black Duck, Anas rubripes 

 (Brewster). M.A. thesis, Cornell Univ. /Ithaca , NY. 



1935 



Christofferson, K. 1935. Common Black Duck, Red-legged Black Duck and Mallard 

 sex ratios. Bird-Banding 6: 138. 



1932 



van Huizen, P. J. 1932 ms. Report on the Black Duck nests on the Blackwater 

 Migratory Bird Refuge, Cambridge, MD. Ms filed in Biol. Survey, Washing- 

 ton, D.C. 



1931 



Pirnie, M. D. 1931. Fall migration of the Black Duck from northern Michigan. 

 Pap. Mich. Acad. Sci., Arts & Letters 15: 485-490. 



1924 



Bergtold, W. H. 1924. The Black Duck in Colorado. Auk 41: 338. 



Henderson, J. 1924. Status of the Black and Mottled ducks in Colorado. Auk 

 41: 471. 



1922 



Phillips, J. C. 1922. Is the Black Duck extending its range? Bull. Am. Game 

 Protective Assoc. 11: 12-13. 



1920 



Phillips, J. C. 1920. Habits of the two Black Ducks, Anas rubripes rubripes 

 and Anas rubripes tristis . Auk 37: 289-291. 



1918 



McAtee, W. L. 1918. Food habits of the Mallard Ducks of the United States. 

 U.S. Dept. Agric. Bull. No. 720. 



1916 



Townsend, C. W. 1916. The courtship of the Merganser, Mallard, Black Duck, 

 Baldpate, Wood Duck, and Bufflehead. Auk 33: 9-17. 



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