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A seabird
The Northern Gannet is exclusively a seabird, living on coastal fringes, up to 200 km from the coast. Its incursions inland are rare, often following storms. Outside the reproduction season, Northern Gannets are found throughout the Northern Atlantic, as far as the shores of Western Africa and the Caribbean Sea. They come together for nesting in forty or so colonies, most of which are situated on European coasts.
This large seabird is a fish eater. It requires about 1/2 kg of fish a day. Its favourite prey consists of species, such as mackerel and herring, which live in shoals and are easily spotted from the sky.
Veritable kamikazes
In French, the Northern Gannet is known as the ‘Fou de Bassan’ – the mad bird of Bassan, a tiny Scottish island. It owes its name to its amazing fishing technique. It spots a shoal of fish from 10 to 40 metres above the waves and, with wings folded back, it hurtles down like a stone, entering the water at around 100 km/h ! Its headlong fall takes it under the shoal. As it makes its way back to the surface, it gulps down its victims from the compact mass of fish, regains the surface and takes to the air once again, its prey already in the stomach.
The physiology of the gannet is perfectly adapted to its fishing technique. The eyes are set in the front of the skull, giving it a field of vision comparable to that of humans, particularly for estimating distances. To withstand the effects of its nosedive, its beak is without nostrils, its jaws are capable of closing hermetically and tiny pockets beneath the skin of its neck, above the flanks, are filled with air just before impact, acting as airbags to absorb the shock.
An outstanding soaring bird
The Northern Gannet also has exceptional gliding and soaring ability, capable of hovering above the waves for hours, searching for food, virtually without flapping its wings, simply relying on the updrafts generated by the swell. For this bird, as for other species of seabirds and birds of prey, we speak of gliding and soaring flight.
Gliding flight is when the bird makes a long slow descent without flapping its wings, like a plane that has cut its motor, whereas soaring flight enables altitude to be maintained, using updrafts in the air. The Northern Gannet excels at this technique, thanks to its aerodynamic body and its light highly-manoeuvrable wings with a wingspan that can attain 1.80 m.
Equipped with all these features, The Northern Gannet is capable of covering enormous distances, sometimes several hundred kilometres, in its search for fish. |