Êtes-vous un étudiant de l'EPFL à la recherche d'un projet de semestre?
Travaillez avec nous sur des projets en science des données et en visualisation, et déployez votre projet sous forme d'application sur Graph Search.
Concept
Phoque de Weddell
Résumé
The Weddell seal (Leptonychotes weddellii) is a relatively large and abundant true seal with a circumpolar distribution surrounding Antarctica. The Weddell seal was discovered and named in the 1820s during expeditions led by British sealing captain James Weddell to the area of the Southern Ocean now known as the Weddell Sea. The life history of this species is well documented since it occupies fast ice environments close to the Antarctic continent and often adjacent to Antarctic bases. It is the only species in the genus Leptonychotes.
Weddell seals measure about long and weigh . They are amongst the largest seals, with a rather bulky body and short fore flippers relative to their body length. Males weigh less than females, usually about or less. Male and female Weddell seals are generally about the same length, though females can be slightly larger. However, the male seal tends to have a thicker neck and a broader head and muzzle than the female. A molecular genetic-based technique has been established to confirm the sex of individuals in the laboratory. The Weddell seal face has been compared to that of a cat due to a short mouth line and similarities in the structure of the nose and whiskers.
The Weddell seal grows a thin fur coat around its whole body except for small areas around the flippers. The colour and pattern of the coat vary, often fading to a duller colour as the seal ages. This coat moults around the beginning of summer. Adults show a counter-shaded colouration that varies from bluish-black to dark grey dorsally and to light grey/silver ventrally. Coats may change to shades of brown before the annual moult. Adult males usually bear scars, most of them around the genital region. Weddell seal pups are born with a lanugo of similar colouration and they moult after 3–4 weeks; later, they turn a darker colour similar to that of adults. The pups are around half the length of their mother at birth and weigh . They gain around a day, and by 6–7 weeks old they can weigh around .
Source officielle
À propos de ce résultat
Cette page est générée automatiquement et peut contenir des informations qui ne sont pas correctes, complètes, à jour ou pertinentes par rapport à votre recherche. Il en va de même pour toutes les autres pages de ce site. Veillez à vérifier les informations auprès des sources officielles de l'EPFL.