FOOD OF SPARROWS BY SPECIES. 

 SNOWFLAKE. 



{Passerina nivalis.) 



The snowflake is a bird of the arctic tundra, above the limit of tree 

 growth. In North America it breeds about Hudson Bay, in the north- 

 ernmost i)arts of Labrador and Alaska, and to the northward. In its 

 northern home it is a white, black-blotched sparrow, of whose habits 

 very little is known, except that it makes a feather-lined nest on the 

 ground, in which it rears four to five young on a diet which probably 

 consists principally of insects. After the breeding season, however, 

 a buff}^ brown becomes mixed with the black and white, and the birds 

 assume a more sparrow-like aspect. They migrate southward with 

 the first severe cold weather, some of them coming as far south as the 

 northern half of the United States, where their appearance is regarded 

 as a sure sign that winter has begun in earnest. Often a flock of a 

 thousand will come with a blizzard, the thermometer registering 30° 

 to 40° below zero; and in their circling, swirling flight, as they are 

 borne along b}^ the blast, they might well be mistaken at a distance 

 for veritable snowflakes. They settle in the open fields and along 

 railroad tracks, where the}^ secure some food from hayseed, grain that 

 has sifted out of the grain cars, and seeds of weeds that grow along 

 the tracks. Here they remain until April, when, in obedience to the 

 migrating instinct, they journey north to nest on the treeless plains 

 of the arctic regions. 



The snowflake differs from many other winter siDarrows, such as 

 the tree sparrow, juaco, and white-throated sparrow, in that its flocks 

 act more nearly as units, the alarm of a single member causing the 

 whole flock to whirl up into the air and be off. A further difference 

 may be noted in its strictly terrestrial habits. When not flj^ing, it is 

 almost invariably found on the ground; and when it does happen to 

 alight in a tree, awkward wobblings betraj^ its discomfort. Where 

 the feeding conditions are favorable, immense flocks of snowflakes 

 may be seen apparently rolling like a cloud across the land, this 

 curious effect being due to the rear rank continually rising and flying 

 forward to a point just in advance of the rest of the flock. At times 

 the}^ feed in company with horned larks. This is particularly notice- 

 able when snow has covered the tops of weeds, and the birds are 

 obliged to repair to the crests of wind-swept knolls where the ground 

 is comparatively bare of snow and the weeds are, consequently, 

 exposed. 



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