THE MIGRATION OF BIRDS.

New Zealand Herald, Volume LI, Issue 15551, 7 March 1914, Page 5 (Supplement)

THE MIGRATION OF BIRDS.

The study of the fascinating subject of the migration of birds teaches us that these periodical movements fall to be divided into several categories. The permanent residents are very few in number, says an English observer, and may almost be in ted on the fingers of the hand. Next we have the summer visitors, that como to us in spring at their nestingtime, and leave us in autumn. Further, we have in autumn vast numbers of birds coming from the north or east on their way to warmer quarters, some of which, no doubt, romain with us until the return of spring ; and finally, these species which pay a passing visit on their southern journey, resting again a while with us on their homeward way in spring. It will he found on closer study of these various movements that many species fall to be included in mora than one of these categories, and of this the thrush is a typical example. So much is this the case that the song thrush has been selected by Mr. Eagle Clarke as the subject of a special chapter in his standard work, entitled "Studies in Bird Migration." Those who have access to his volumes will find therein the result* of years of laborious and selfdeny observation. Suffice it. here to say thai, while, no doubt, a few thrushes remain here and there as permanent residents in specially favoured localities, the great, bulk of those that nest with us move, as winter approaches, to more sheltered quarters, and may be called partial migrants; others again leave our shores, musing the channel, such movements having been observed as early as the month of August. On the other hand, hosts of thrushes begin to arrive in early autumn on our northern coasts from their Scandina . ian homes. To quote Mr. Eagle Clarke's words-—"ln addition to being a resident and summer visitor, this favourite songster is also a winter visitor to the British area, a bird of passage along our shores in the spring and autumn, and lastly, a winter migrant ... an excellent example of the complex nature of the phenomena of bird migration." So, too, if to a lesser extent, with the blackbirds, although these being of a hardier nature are not so readily moved by stress of weather ; but great numbers reach and leave our coasts in like manner in company of their congeners. If proof of what has been said of the. thrush were needed, it may suffice to say that a nestling song thrush, marked with a ling at Skene House. Dunecht, Aberdeenshire, on June 4. ISIO, by Miss D. Hamilton, was shot on November 6, 1910, by " a party of hunters" at Valle do Sunnos, about 70 English miles N.N'.E. of Lisbon, Portugal.