Congdon—Saskatchewan Birds. 
585 
lower water than that of the Coot, as a, rule 1 , and in a thicker 
growth of grass or rushes which afford it better concealment. A 
mass of vegetation is heaped npi on some broken-down rushes or 
grass, a rather deep hollow is made and! lined with grass and a 
little down. The nest will rise and fall with the water to a 
certain extent, but this motion is usually limited by those rushes, 
used in its construction, whose roots are still fast in, the bottom 
of the slough or lake. A nest of the Redhead is shown in 
Plate XLVI. 
147. Caxvas-back:. 
Ay thy a vallisneria (Wils.). 
The Canvas-back is conspicuous among the ducks observed, 
commonly frequenting during the nesting season the sloughs 
bordered by grass or rushes with an area of open water in the 
center. Frequently the male bird would be seen swimming 
about in the open water in the neighborhood of a nest, and the 
female, on being flushed from the nest, would join her mate. A 
big drake was shot on August 6, and the throat and crop con¬ 
tained water snails. 
The nesting site chosen by the Canvas-back is very similar to 
that of the Rjedhead and the nest itself differs from the nest 
of the Redhead but little, if any. The place generally chosen 
is a clump of tall grass growing in a slough where the water is 
from a foot to two or three feet deep, or it may be a cluster of 
rushes in the deeper water of a slough or shallow lake. Here, 
some of the grass or rushes are broken down and a large amount 
of dead grass or reeds is piled up and deeply hollowed. Then 
a cosy lining and rim of down is added. The nest may be well 
hidden by surrounding clumps of grass, but usually it is built 
near small, open stretches of water. A typical nest is pictured 
in Plate XLVII. One nest, situated among the rushes of a deep 
slough, could be seen from a distance of three or four rods. It 
was rather larger than most of the nests of the Canvas-back, 
measuring thirty-six inches outside diameter; eleven inches in¬ 
side diameter; eight and one-half inches outside depth and four 
and one-half inches depth inside. Another nest was built up 
from the bottom 1 of a slough where the water was about a foot 
deep. It was but slightly hidden by the bunch of grass in which 
it was built. A nest of the Canvas-back containing eight eggs 
of that bird and eight of the Redhead, is shown in Plate XLVI. 
