11 



length of migration is doubtless the Arctic Tern, a bird that nests from 

 the gulf of St. Lawrence to the polar regions and winters as far south as the 

 Antarctic continent. 



The methods of migration are nearly as varied as their extent. Some 

 species drift along throughout the day from treetop to treetop, from wood 

 patch to wood patch, gradually working their way in the desired direction. 

 Others take long flights, some high in the air, others lower. Some travel 

 altogether by day; others travel at night and we are aware of their passage 

 only through accidental opportunities, their faint voices coming down 

 to us from overhead in the darkness, or by their sudden appearance about 

 us in the morning. They travel in flocks of single or mixed species, scattered 

 groups, or as individuals. 



Many species, if not all, follow more or less definite routes to and 

 from their breeding grounds and some go and return by altogether different 

 paths. Comparatively small bodies of water deflect some species from 

 their course, others unhesitatingly cross vast reaches of sea, indifferent 

 to nearby and convenient land passages that are made use of by closely 

 allied species. In some species the older birds precede; and in others 

 the males precede the females. 



How birds find their way is still only vaguely understood, and indi- 

 viduals far out of their natural range and course show as clear evidence of 

 being as hopelessly lost as any other animal would be on unfamiliar 

 ground. Certainly experience has much to do with it and undoubtedly 

 young birds are largely guided by the movements of their elders who, it 

 can be assumed, through previous experience, already know and can lead 

 the way. We can understand how birds can follow great landmarks — 

 large river systems, mountain ranges, or sea-coasts — in their journey, but 

 no sense with which we are familiar explains how some species return 

 unerringly to lonely oceanic islands over wastes of monotonous sea. It 

 may be that they have a special sense which aids them in orienting them- 

 selves. 



PROTECTION. 



In food habits, birds are eminently adaptable; seeds, plants, fruit, 

 insects, flesh, or fish are all acceptable to various species and, consequently, 

 nearly all regions have their quota of appropriate birds. A bird fives fast, 

 its heart beats more rapidly than that of other animals, the blood temper- 

 ature is higher, and it consumes an enormous amount of energy in flight. 

 This feverish heat and strenuous exertion require a correspondingly large 

 amount of food; consequently the bird as an economic factor is one to be 

 regarded seriously. Though it may be an exaggeration to say, as some 

 writers have inferred, that the whole balance of nature depends upon birds 

 and that without them the country would be a barren waste with no life 

 other than insects, yet birds cannot be seriously reduced in number without 

 the gravest results. The destruction of tons of weed seeds and millions 

 of insects must necessarily have a great influence upon human welfare and 

 neglect of this fact must seriously react upon any community that fails 

 to give proper protection to its birds. 



However, the problem of the status of individual species of birds is 

 not the simple thing that it superficially appears to be. More than a 

 cursory examination is necessary and many things must be considered in 



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