Vol. XIXT Bent, Nesfhts' Habits of AnatidcE in N. Dakota. Q 



1902. J ' .s -' y 



reeds growing in the drier portions. The Redheads' nests were 

 all located in the shallower parts of the slough where the reeds 

 and flags were growing less thickly. 



Pied-billed Grebes, Canvasbacks and Ruddy Ducks were nest- 

 ing in this slough, as well as hundreds of Yellow-headed Black- 

 birds and Coots. 



The Redheads' nests found here on June 10 contained six, ten, 

 fourteen, and sixteen eggs respectively, none of which were col- 

 lected. The latter of these is shown in the photograph (PL III, 

 Fig. 2); it was located in the centre of a tangled mass of broken 

 down dead flags, in a nearly dry, open space, near the edge of the 

 slough, well concealed from view by the arching over of the dead 

 flags above it. The bird proved to be a close sitter, as we twice 

 flushed her from the nest. We tested one of the eggs and found it 

 far advanced in incubation. 



The Redhead seems to be particularly careless, about laying its 

 •eggs in other ducks' nests. We found one of its eggs in a Ruddy 

 Duck's nest in this slough, and in three cases found from three to 

 four of its eggs in nests of the Canvasback, on which the latter 

 duck was incubating ; but we never found the eggs of any other 

 species in the Redheads' nests. 



The eggs of the Redhead can generally be distinguished from 

 those of any other species, as they are usually quite different in 

 color, size and texture. The shell is extremely hard and flinty, 

 with a smooth, slightly glossy surface, and quite thick; it will dull 

 the cutting edges of the best drills in a short time. In shape they 

 vary from a somewhat rounded to a considerably elongated ellip- 

 tical ovate, sometimes nearly oval. 



In color they vary from a light olive bufi:, matching almost 

 exactly certain types of Mallard's eggs, to a light cream buff. 

 The eggs are larger than the Mallard's eggs, and the nest is 

 •entirely different, being made of dead reeds and lined with white 

 down. The eggs are entirely different in color from those of the 

 Canvasback, which builds a somewhat similar nest and in similar 

 situations, but lines it with gray down. 



The measurements of twenty-six eggs in my collection show the 

 following figures : length, 2.63 to 2.31; breadth, 1.79 to 1.68; 

 average, 2.45 by 1.72. 



