BIRD TOURISTS

Evening Star, Issue 19409, 18 November 1926, Page 16

BIRD TOURISTS

AMAZING JOURNEYS SWALLOWS' HON-STOP 1,000 MILES We have not many migratory birds that visit New Zealand, there being the godwit, oui most noted traveller, tho two cuckoos (the shining and the long-tailed), and one or two others, but few as they are we know really very little about their movements (says a writer in the Auckland ‘Star’). People say that the god wits (native name “ kuaka ”) go to Siberia, but it is doubtful whether the matter has been properly established. Even the great scientists in Europe are still very much in the dark on the matter of bird-migration, so perhaps it is not surprising that we away in far New Zealand should not be very well up in a difficult subject. Readers who know their Gilbert White will not need to be told that tho old naturalists had weird ideas about ” where the _ birds went in winter,” and even Gilbert, who was such a thorough-going, truthful observer, made some rather odd guesses. / . Cocksure writers have spread the impression that wo knoik all about the why and wherefore of migration. We really know practically nothing. Only in the last twenty years have we even begun to find out how migrating birds behave. It was thought not long ago that migration was performed at vast heights, till airmen, patrolling in the war, proved that birds rarely rise above 5,000 ft. Tht cherished belief of some naturalists that they could do 250 miles an hour has also been demolished through careful timing by airmen and others. We now know that most birds migrate, and that seventy miles an hour is the utmost they can cover without a favoring wind. Few small birds do more than forty miles an hour; swallows, the most famous migrants of all, probably only average about twenty-five. There is only ono way to make_ sure where the birds go, and that is to ring them. In the Old Country this course has been adopted, and some amazing facts have come to light, making the travels of the feathered migrants even more wonderful _ than w'e thought. Light aluminium rings, numbered and bearing a London address, are attached to the legs of birds that are captured when young and then liberated. When the number of the ring is reported its history can be looked up; and in this way the amazing travels of birds are slowly being brought to light. A wild duck bred in Aberdeenshire, was found tho next summer bringing up a brood of young in Denmark, where she had probably travelled in company with Danish birds returning from Britain. A black-headed gull, who was evidently determined to see the world, had actually wandered from Rossitten on the Baltic to Barbados across the Atlantic by the time he was four months old. Three young sheld ducks were marked in Hampshire on _ tho same day; one was found next winter in Cornwall, another in Schleswig-Hol-stein in the summer after; and the third in North Germany when it had just turned four. On the Continent they ring storks wholesale, and 100 have been found in Africa, mostly in tho south-east. A Sandwich tern, which was hatched on tho Fame Isles in the 1919 season, turned up near Cape Town last August; he was sis years old, and it seems more than doubtful if he had been home at all last summer. Judged simply as a feat of endurance, the swallows’ migration is known now to be much moio marvellous than it was ever suspected of being. Six of seven British swallows found in South Africa were less than a year old: the youngest had covered a clear 6,000 miles in tho first seven months of his life. The extraordinary thing is that they go sc much farther than they need, if it were simply a question of food and warmth. In fact, they will travel over half as far south of the tropics as England is north of them. From these colossal distances they find their way back not only to the country but to the precise spot where they were hatched, and a swallow has been known to keep the same mate three years running. In Hungary, one used the same nest for six years. But they are not all infallible. Hopelessly lost wanderers of purely Asiatic forms are constantly turning up on Fair Isle, a miserable little rock marooned between tho Orkneys and Shetlands. A swallow who had evidently lost his way was seen by an unimpeachable _ authority to settle on a yacht 930 miles from tho nearest land,"'which, of course, is most unlikely to have been the actual point whore he started, even if ho had flown in a straight line. Others have been found almost as far out at sea, and the power of a swallow to perform non-stop flights of a thousand miles is almost beyond doubt. The American golden plover is believed to travel more than double as far without a rest. The Atlantic must frequently be crossed, for there are_ already at least five records of the flight among the comparatively few ringed birds that are ever heard of again. Tho investigators are accumulating a> whole mass of facts about migration, but they do not make us much wiser. More often they seem to open fresh fields of bewilderment. But at least they mako for humbleness; no sane ornothologist now would dream of claiming to know a quarter as much about migration as they all thought they knew fifty years ago. We can do nothing but go on finding things out, for wo can only fee) sure of odd facts here and there, and how they will fit in remains to be seen.