Heinz, G. H. 1980. Comparison of game-farm and wild-strain Mallard ducks in 

 accumulation of methylmercury. J. Environ. Pathol. Toxicol. 3: 379-386. 



Jackson, D. H. 1980. Sociobiology of breeding drake Mallards in northern 

 Iowa. M.S. thesis, Mich. St. Univ. /East Lansing, MI. 48 pp. 



Klint, T. 1980a. Influence of male nuptial plumage on mate selection in the 

 female Mallard ( Anas platyrhynchos ) . Anim. Behav. 28: 1230-1238. 



. 1980b. On the incidence of rahb calling in male Mallards Anas platy- 

 rhynchos . Ornis Scand. 11: 81-84. 



Lipcius, R. N., C. A. Coyne, B. A. Fairbanks, D. H. Hammond, P. J. Mohan, D. J. 

 Nixon, J. J. Staskiewicz and F. H. Heppner. 1980. Avoidance response of 

 Mallards to colored and black water. J. Wildl. Manage. 44: 511-518. 



Lutz, W. 1980. Uber einer Fall von Hypermelie bei einer Stockente ( Anas platy- 

 rhynchos L . ) . [A case of hypermalia in a Mallard ( Anas platyrhynchos L. ) . ] 

 Z. Jagdwiss. 26: 233-236. 



McEwan, E. H. , and P. M. Whitehead. 1980. Uptake and clearance of petroleum 

 hydrocarbons by the Glaucous-winged Gull ( Larus glaucescens ) and the Mal- 

 lard Duck ( Anas platyrhynchos ). Can. J. Zool . 58: 723-726. 



McGarry, R. C. and T. K. R. Bourne. 1980. Annular bands of lymphoid tissue in 

 the intestine of the Mallard duck Anas platyrhynchos . J. Morphol. 163: 

 1-8. 



Mitgard, U. 1980. Heat loss from the feet of Mallards Anas platyrhynchos and 

 arteriovenous heat exchange in the rete tibiotarsale. Ibis 122: 354-359. 



Mueller, H. C. and P. G. Parker. 1980. Naive ducklings show different cardiac 

 responses to hawk than to goose models. Behaviour 74: 101-113. [In Eng- 

 lish with German summary.] 



Mueller, N. S. 1980. Mallards capture and eat American Toads. Wilson Bull. 

 92: 523-524. 



Nelson, D. A. 1980. A Mallard X Mottled Duck hybrid. Wilson Bull. 92: 523- 

 524. 



Ringelman, J. K. and L. D. Flake. 1980. Diurnal visibility and activity of 

 Blue-winged Teal and Mallard broods. J. Wildl. Manage 44: 822-829. 



Sugden, L. G. and E. A. Driver. 1980. Natural foods of Mallards in Saskatch- 

 ewan parklands during late summer and fall. J. Wildl. Manage. 44: 705-709. 



Szaro, R. C. , N. C. Coon and W. Stout. 1980. Weathered petroleum: effects 

 on Mallard egg hatchability. J. Wildl. Manage. 44: 709-713. 



Tallman, D. A. and P. M. Bultsraa. 1980. Mallard migration in the Ordway Mem- 

 orial Prairie Region, Leola, South Dakota. S. Dak. Bird Notes 32: 28-31. 



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