No%.,1911 
DUCKS OF THE BARR LAKE REGION, COLORADO 
191 
snake with a stick. Upon dissecting it we found no signs whatever of the other 
eggs, a fact which raised the question as to whether the two which had disappeared 
since the preceding day had been entirely digested (shell and all) within that time, or 
whether more than one snake was pilfering this particular nest. A fortunate ex- 
posure caught the egg just as it was being disgorged from the snake’s mouth. 
Eight to eleven eggs apparently constitute full sets, and ten was the average 
number found, but one nest was found containing five heavily incubated eggs, 
which hatched July 6, 1908. The earliest nest found during the three seasons was 
May 11; the first egg in this set was probably laid May 9. The average date for 
complete sets was the last week in May, and many of the eggs hatched during the 
first week in June. 
Broods of young birds were kept well concealed by the parents until able to 
Fig. 63. nesting site ok ruddy and canvasb.ack. this muskr.at house con- 
tained AT THE SAME TIME TWO NESTS OF THE RUDDY AND ONE 
OF THE CANVASBACK 
care for themselves. We saw but two or three broods, but in each case the mother 
was very bold, using every possible subterfuge to lead us away from her babies. 
REDHEAD {Mariia aniericana) 
Cooke, in the second supplement to “Birds of Colorado,” published in 1900, 
states that “facts are accumulating which make it probable that this species will in 
the near future be accounted among the breeding birds of Colorado,” and this pre- 
diction was fully verified by our discovery of several nests during 1906, 1907 and 
1908. Five nests were found which we could positively attribute to the Redhead, 
and a few others which in all probability belonged to this species, but which we 
were unable to identify beyond doubt. Further than this enough pairs of Red- 
heads as well as single males in full breeding plumage were seen during May, June 
and July of each of these years to satisfy us that the birds were breeding along 
