120 INTRODUCTION OF BIRDS. 
climatic excess than quadrupeds. Besides, they generally want 
the special means of shelter against the inclemency of the 
weather and against pursuit by their enemies, which holes and 
dens afford to burrowing animals and to some larger beasts of 
prey. The egg is exposed to many dangers before hatching, 
and the young bird is especially tender, defenceless, and help- 
less. Every cold rain,every violent wind, every hailstorm dur- 
ing the breeding season, destroys hundreds of nestlings, and the 
parent often perishes with her progeny while brooding over it 
in the vain effort to protect it.* The great proportional num- 
bers of birds, their migratory habits, and the ease with which 
by their power of flight they may escape most dangers that 
beset them, would seem to secure them from extirpation, and 
even from very great numerical reduction. But experience 
shows that when not protected by law, by popular favor or 
superstition, or by other special circumstances, they yield 
very readily to the hostile influences of civilization, and, though 
the first operations of the settler are favorable to the increase of 
many species, the great extension of rural and of mechanical 
noticeable exception to the law of regularity which seems to govern the 
movements and determine the habitat of birds. The proper home of this bird 
is the steppes of Tartary, and it is not recorded to have been observed in 
Europe, or at least west of Russia, until the year above mentioned, when 
many flocks of twenty or thirty, and even a hundred individuals, were seen in 
Bohemia, Germany, Holland, Denmark, England, Ireland, and France. A 
considerable flock frequented the Frisian island of Borkum for more than five 
months. It was hoped they would breed and remain permanently in the 
island, but this expectation has been disappointed, and the steppe-grouse 
seems to have disappeared again altogether. 
* Tt is not the unfledged and the nursing bird alone that are exposed to 
destruction by severe weather. Whole flocks of adult and strong-winged 
tribes are killed by hail. Severe winters are usually followed by a sensible 
diminution in the numbers of the non-migrating birds, and a cold storm in 
summer often proves fatal to the more delicate species. On the 10th of June, 
184-, five or six inches of snow fell in Northern Vermont. The next morning 
I found a humming-bird killed by the cold, and hanging by its claws just be- 
low a loose clapboard on the wall of a small wooden building where it had 
sought shelter. 
