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leg they fly back to Canada over Central America and the USA. Some furtherastonishing migration feats are:– theJapanese snipe (Capella hardtwickii) flies 5,000 km to Tasmania– the East Siberian spine-tailed swift (Chaetura caudacuta) migratesfrom Siberia to Tasmania– the migration route of the American sandpipers (e. g. Calidris melanotus= grey breasted sandpiper) covers 16,000 km from Alaska to Tierradel Fuego at the southern tip of South America.A3.4.4.2 The Flight of Migrating Birds: A Navigational MasterpieceFinn Salomonsen, a Danish ornithologist, writes the following about thein-flight orientation of birds [S2]: “The ability of birds to find their waywhile flying is a mystery and a puzzle. Few other questions have over theyears given rise to so many theories and speculations as this one.” Thisnavigational ability is indeed a supreme wonder, since birds do not havecomplex gyroscopes, compasses, or maps, and environmental conditionslike the position of the sun, wind direction, cloud cover, and day-nightrhythms, keep changing all the time. When terrestrial birds have to crossan ocean, as we have seen in the case of the golden plover, a small error indirection would result in their floundering helplessly over the open oceanand finally plunging to their death. Setting an exact course is not a questionof trial and error, because a large majority of the migratory birdswould never reach their destination without exact navigation. No speciescould survive such great losses. Any evolutionistic view of this fact can berejected out of hand. The idea that juvenile birds are shown the way bytheir parents plays a minor role at most, since many kinds of birds flysingly. We thus have to assume that migratory birds possess an inherentsense of direction which enables them to orientate themselves with respectto geographical direction and to stay on course. This sense of direction isdemonstrated by Salomonsen in the case of two kinds of small birds livingin western Greenland and which both migrate to the south in autumn. Thewheatear (Oenanthe oenanthe) and the snow canary live in the sameregion, and they often begin their migration at the same time. But theirways part after arriving in southern Greenland. The snow canaries continuedirectly south to spend the winter in America, while the others turnFigure 45: The flight of the East Siberian golden plover.For the migration of up to 4,500 km from Alaska to Hawaii, the amount of availablefuel is 70 g. If this flight is undertaken by a single bird (curve G A ), it would haveconsumed all its fat reserves after 72 hours and would plunge into the ocean 800 kmfrom its destination. On the other hand, flying in a V formation (curve G V ), reducesthe energy consumption by 23 %, so that the birds reach their destination safely.244