Oppenheimer, R. W. 1968. Colour preferences in the pecking response of newly 



hatched ducks ( Anas platyrhynchos ) . J. Comp. Physiol. Psychol. 66 (Monogr. 

 Suppl.): 1-17. 



Post, W., Jr. 1968. Mallard breeding in Barnwell County, S.C. Chat 32: 100- 

 101. 



Prince, H. H. 1968. Inheritance of fecundity, and embryonic and juvenile 



growth in Mallard ducks. Ph.D. thesis, Virginia Poly. Inst ./Blacksburg, 

 VA. 



Singleton, J. R. 1968. Texas' mistaken Mallards. Texas Parks & Wildl. 26: 

 8-11. 



Young, C. M. 1968. Island nesting of ducks in northern Ontario. Can. Field- 

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1967 



Johnsgard, P. A. 1967. Sympatry changes and hybridization incidence in Mal- 

 lards and Black Ducks. Am. Midi. Nat. 77: 51-63. 



Matthews, G. V. T. 1967. Some parameters of "nonsense" orientation in Mal- 

 lard. Wildfowl Trust Annu. Rept . 18: 88-97. 



Olney, P. J. S. 1967. The WAGBI-Wildfowl Trust Experimental Reserve. II: The 

 feeding ecology of local Mallard and other wildfowl. Wildfowl Trust Annu. 

 Rept. 18: 47-55. 



Young, C. M. 1967. Overland migration of duck broods in a drought-free area. 

 Can. J. Zool. 45: 249-251. 



1966 



Folk, C, K. Hudec and J. Toufar. 1966. The weight of the Mallard, Anas platy- 

 rhynchos and its changes in the course of the year. Zool. Listy 15: 249- 

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Lippens, L. 1966. Essai d ' interpretation des observations et du baguage des 



canards colverts ( Anas platyrhynchos ) dans les reserves de Meetkerke (51° 



14' N, 3°09'E) et de Knokke (51 "21 'N, 3°18'E), en Belgique de 1936 a 1966. 



Gerfaut 56: 315-373. [In French with English summary.] 



Malone, C. R. 1966. Regurgitation of food by Mallard ducks. Wilson Bull. 78: 

 227-228. 



Marcstrom, V. 1966. Mallard ducklings ( Anas platyrhynchos L.) during the first 

 days after hatching. Viltrevy 4: 343-370. 



Pirkola, M. K. 1966. Sinorsan ravinnosta maha-analyysien valossa. [On the 



feeding habits of the Mallard ( Anas platyrhynchos ) as revealed by crop and 

 gizzard samples.] Suomen Riista 18: 67-81. [In Finnish with English sum- 

 mary. ] 



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