RIVER DUCKS 
87 
Field Marks. Under favourable conditions the general outline, rounded head, and 
shorter, thicker bill will separate these, and the Sea or Bay Ducks, from the mergansers. 
They rise more steeply from the water than either. When under way, the neck is inclined 
slightly upward from the body, and they lack the drawn-out appearance of the mergansers. 
The flock formation is usually irregular with little order or alinement. They are more 
difficult to distinguish from the Sea or Bay Ducks, but in general are longer and more 
shapely in appearance, with more slender necks. They are probably more easily recog- 
nized by species. 
Figure 125 
Foot of Surface-feeding Duck; 
scale, 
Bill of Surface-feeding Duck; 
scale, §. 
Nesting. Usually on the ground. Occasionally in trees. 
Distribution. As a class the Pond and River Ducks are more abundant in the interior 
than on either coast. 
As the names imply, the River and Pond Ducks frequent our smaller 
inland waters more than they do the larger ones. They feed from the 
surface by “tipping” and reaching under the water, and rarely dive. The 
food is gathered in the bill and the water squeezed out, the laminae of the 
bills retaining the solid matter. 
Economic Status. Being strictly water-birds and vegetable and insect 
feeders, their food habits generally are not harmful to human interests. 
It has lately been shown that ducks feed largely upon mosquito larvae 
and that they may do surprising good in this direction. By actual experi- 
ment, a pair of ducks in a small pond did more to reduce these pests in it 
than a considerable school of goldfish. As game, they are of great import- 
ance, See pages 68-73. 
132. Mallard Duck. green- he ad. le canard ordinaire. Anas platyrhynchos. 
L, 23. Plate VI A. 
D-istindions. The male cannot be mistaken for any other wild duck, though many 
domestic strains approach it closely. The female is often referred to other species and is 
sometimes called “Grey Duck.’’ There are several other ducks approaching her in colora- 
tion, but the purple speculum with the white bar both before and behind the speculum 
are good distinguishing marks (Figure 127). 
Field Marks. Green head and white neck-ring are conspicuous recognition marks for 
the adult male. The speculum with its white bars will identify the female in life. The 
tail of both sexes shows a general whiteness in flight that is quite characteristic. 
Nesting. On the ground usually; in high grass or reeds, occasionally at a considerable 
distance from water, and because of this it often thrives in sections from which other 
species have been driven away. 
Distribution. Over practically the whole of Canada except in the far north, but less 
common in the extreme east. Breeds throughout Canada except where disturbed by 
settlement, but mostly west of Ontario. 
