NORTH AMERICAN GREBES. 7 
economic significance, as these small fishes are present in great 
_ schools and the grebes are few in number. Other stomachs con- 
tained merely a few bones of fishes that were too far advanced in 
digestion to be identified. J. Macoun, of the Canadian Geological 
Survey, has reported finding a large salamander (Ambystoma) in 
the stomach of one of these birds. ~ 
SUMMARY. 
‘ 
, 
; 
The material available is scanty, but seems to show that the west- 
ern grebe depends almost entirely upon fishes as a source of food. 
Those taken, however, are seemingly of little importance. The 
species inhabiting the streams and shallow lakes upon which this 
grebe has its summer home are, as a rule, of little economic value. 
In other regions the grebes do not occur in sufficient numbers to 
make them a factor of any moment in the continuance or abundance 
of any species of food fish. Their feeding is confined to the numer- 
ous smaller fry, and the destruction of a few is of no economic 
significance. The brief survey that it has been possible to make of 
its food indicates that the western grebe is worthy of protection as 
an interesting form of life, having no traits that may be marked 
as, Injurious. 
‘ ES ae Papas, 5 PP Mey 
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HOLBOELL GREBE. 
(Colymbus holboelli.) 
The Holboell, or red-necked, grebe has a range extending over 
most of the northern part of North America and eastern Asia. In 
our continent it breeds from northern Alaska and Ungava (North- 
west Territories) south to the northern border of the United States 
from Washington to southwestern Minnesota. In winter it passes 
in migration south as far as California, Colorado, the Ohio Valley, 
and North Carolina, and occurs north to British Columbia, Wiscon- 
sin, and Maine wherever there is suitable water free from ice. 
During the winter season these grebes frequent the bays and open 
ocean along our coasts, and large lakes and streams inland. Their 
habit of remaining in the North on the open water of large lakes 
during winter often leads to their destruction, as many cases are 
known in which the birds have been caught during severe weather 
and frozen into the ice. Grebes usually are unable to rise in flight 
from a hard surface, and require a considerable start in order to 
gain momentum for ‘flight from the water. When caught by en- 
croaching ice, therefore, they may be unable to escape unless they 
chance upon a permanent air hole, where they may live until the re- 
turn of milder weather. 
On their breeding grounds the Holboell grebes are reputed to be 
very shy, and, though found in the open during much of the re- 
mainder of the year, they are perhaps as little known generally as 
any of our grebes except the pygmy Mexican grebe, which barely 
enters our boundaries from Mexico. 
FOOD. 
’ The material available for the detailed study of the food of this 
__ bird consists of 46 stomachs, representing all the months of the year 
