BIRD LIFE STUDY

Hokitika Guardian, 4 June 1929, Page 8

BIRD LIFE STUDY

FROM THE A lit

(15,V HARRY lIAREED, Author of “ Twenty-Five Years of Flying.”

Passing daily, as they do now, over aerial routes extending in all directions, aeroplane pilots arc in a unique position to throw light on such Hnscinating subjects as the height and speed at which birds fly, and also upon the wonders of bird migration. By means of schemes which it is hoped may he developed internationally by bird societies and aeronautical associations, airmen are to lie asked to compile reports of their observations of 'leathered foik. incorporating in them such special data as ornithologists require.

Already from information , obtained verbally 'from air express pilots, it appears that birds arc rarely sighted above a height of about 11,000 leet. Occasionally, however, there is an exception to this rule. One airman, not long ago, when at an altitude of nearly 12,000 Ifeet, saw a couple of birds, which he took to lie eagles, flying at a height considerably above that of his machine.

AIR. WATCH AND GROUND WATCH

Many theories, which need to he proved or disproved, exist as to the height attained by birds when on migration. It lias been held that the\ reach, sometimes, elevations of nearly 20,000 feet. Other estimates put the average figure at not more than about 5,000 'feet. It is in regard to such a question that ornithologists consider the obsolvations of airmen may prove .valuable. With the opening up of new long-dis-tance airlines, and with pilots Hying by night as well as day, special opportunities should'be forthcoming 'for systematic studies of bird migration on a widespread scale, the observations of airmen high alo'ft reinforcing those ot ground watchers from suitable pilots. Very different is the attitude of various birds when confronted suddenly by an aeroplane. Some, such as eagles, often want to fight; and dangerous creatures these big birds may prove should they charge at an aeroplane pell-mell. Not long ago a high-flying machine was attacked by several pugnacious eagles. Their fierce darts at the acrophuie so damaged it that an immediate descent became necessary and the pilot made suclf a bad 'landing that lie received fatal injuries, another occupant of the machine being hurt. in one ease, while an airman was above some mountains, an eagle winch flew at him appeared, after circling round the aeroplane, to make a. definite swoop at the idiot rather than at the machine. The bird was driven oil by pistol shots.

CAUTIOUS EAGLE

During ii ICuropean air lour, which she made in a “ -Motl. ” light nerophme. tlio Dnclioss of lied lord, who is nil ardent student of bird life, ra", when over the Pyrenees,* one particularly line specimen (if a mountain carde As she wished to photograph it "her pilot, Capt, C. IX Pmrnard. dived towards the bird. Bnt in tins instance the eagle was cautious rather than aggressive and sped away earthward, eluding all pursuit. .Many birds, when they see an aeroplane, are frightened. They want to get out of the way as quickly ns possible. There is a story ot a >laminerrreir—a bird of prey— which, after it had turned tail, was pursued deliberately bv an aeroplane pilot, and which, in diving in panic to escape, attained a speed estimated at more than 100 miles an hour. Sometimes birds evince no fear at all of aeroplane, They appear in playful mood and amuse themselves by gambolling round the machine. One la itisli pilot, when flying up from the coast to London, encountered a number of swifts. These graceful birds wheeled and dived round the aircralt as though intent upon giving the airman a demonstration of their skill.

OLTSTKTRPKD BY SWIFTS

What pilots are to be asked to observe particularly is the speed of birds. Interesting experiments may, it is imped, he feasible in this regard. In an instance already recorded the pilot of an aeroplane cruising at just- on 10. J miles an hour attracted the attention of some swifts, which .not only oveilook the aeroplane but outstripped it with apparent ease. In “The Daily -Mail” the other day a correspondent described how, during the war. pilots flying above the dune' of Western Belgium matched their aeroplanes against teal and mallard both off which seemed capable of well over 100 miles an hour.

Plans are being discussed for tests in which it is Imped, by means of observations from the air. to throw light upon the question of the eyesight ol birds, known by ornithologists to he amazingly keen and declared to he something like 100 times as acute as that of any human being. In this connection the instance is cited ol kestrel--which, while hovering high alolt. will detect subdl lieetles moving across tin* surface of the ground and swoop down upon them.