The Migration of North American Birds (1935)

One of the best examples of rapid migration is found in the gray-cheeked thrush (_Hylocichla minima aliciae_). This bird winters in Colombia, Ecuador, Peru, Venezuela, and Briti...

Of all species of North American birds, the Lapland longspur (_Calcarius lapponicus_) seems to be the most frequent victim of mass destruction from storms. These birds sometimes...

Experimental work has abundantly demonstrated the effect of increased light upon the growth, flowering, and fruiting of plants. Similarly, experiments with the common junco, or...

Another route from these great marshes crosses the mountains in an easterly direction, but almost immediately turns southward through Colorado and New Mexico, and continues to w...

Figure 17.--Distribution and migration of the scarlet tanager. During the breeding season individual scarlet tanagers may be 1,900 miles apart in an east-and-west line across th...

The males and females of some species may migrate either simultaneously or separately. In the latter case it is usually the males that arrive first, sometimes great flocks of ma...

+---------------------------------------------------------+ | UNITED STATES | | DEPARTMENT OF AGRICULTURE | | | | CIRCULAR No. 363 | | | +---------------------------------------...

The migration of birds as it is known today had its beginning in times so remote that its origins have been entirely obscured, and it can be interpreted now only in terms of pre...