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A very exceptional beak
Pelicans are corpulent. They feature among the largest birds capable of flight. Certain species have a wingspan of 3.5 m and weigh up to 13 kg.
The pelican is known, above all, for its incredible beak, equipped with an enormous elastic pouch, which it uses as a net to capture and transport its prey. With a capacity of 13 litres, it can hold up to 4kg of fish.
Pelicans are excellent gliding and soaring birds and can cover long distances. They flap their wings very little and make good use of rising currents of air. They can fly up to 24 hours without stopping and cover 500 km in a day. The highest flying speed recorded is 56 km/h.
Flying in a V…
Geese, swans and cranes reserve the « V » formation for their long migrations. Pelicans, on the other hand, adopt it for all their flights (provided they are sufficiently numerous). To find out why pelicans favour this way of flying, scientists from the Centre for Biological Studies at Chizé have studied them in full flight, making the most of the opportunity offered by the shooting of the film, Le peuple migrateur (Jacques Perrin).
Two hypotheses were formulated. The first postulated that, by flying in a « V », the birds were economising their energy. The second, that it provided them with a social benefit : communication, protection against predators…
... to save themselves energy
To get to the heart of the matter, the pelicans were equipped with cardiac rhythm recorders and their flight filmed with a digital camera. Conclusion : flight in « V » formation enables the birds to fly as quickly as in solo flight, whilst considerably reducing energy expenditure.
By studying the films and measuring the wing-flapping frequency very precisely, the scientists observed that the birds in the centre of the formation glide for a much longer time than those on the edges of the “V”. This could explain the overall gain in energy from flying in formation. |