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Air Tahiti Magazine 52
birds of french polynesia like nowhere else in the world tahiti and her islands host more than a hundred bird species, 27 of which cannot be found anywhere else in the world. some live only on one archipelago, or even only on one island. these species have adapted to the particular environment of french polynesia, made of scattered islands 6 000 km away from the nearest continents. © a.gouni - sop manu rousserolle de rimatara (acrocephalus rimatarae). l une des trois especes endemiques de l avifaune terrestre des australes. avec le lori de kuhl, petite perruche au plumage multicolore et le chatoyant koko ou ptilope de hutton. rimatara reed-warbler (acrocephalus rimatarae). one of the three endemic bird species of the austral islands, with kuhl s lorikeet, a small multicolored parakeet and the shimmering koko (or rapa fruit dove). l histoire de la presence des oiseaux en polynesie francaise est indissociable de l histoire de cet environnement insulaire, au passe geologique relativement recent. dissemine sur une surface aussi vaste que l europe, l ensemble des iles constituant l entite politique polynesie francaise, est situe a 6 000 kilometres environ des plus proches continents : amerique du sud, australie. agees de quelques millions d annees « seulement », ces iles d origine volcanique, n ont pas vecu la longue histoire de l apparition de la vie sur les continents. une histoire qui s etend sur des centaines de millions d annees. les iles polynesiennes apparaissent alors que tous les grands groupes vegetaux et animaux sont deja apparus depuis bien longtemps, ailleurs. les anciens volcans emerges, mettront encore des milliers d annees pour accueillir et permettre la croissance d une flore et d une faune essentiellement venues par voie des airs. des facteurs physiques, comme les vents, interviennent en effet dans la dispersion du pollen et des graines, meme sur de grandes distances. des petits insectes et des araignees peuvent aussi etre portes jusqu a une altitude de 1 000 metres et ont ete, sans doute, les premiers occupants des iles polynesiennes, beneficiant par exemple d accelerations des vents au cours de cyclones ou d ouragans. ce fut aussi, le cas des oiseaux de mer que n effraient pas les grandes distances. des especes d oiseaux de petite taille ont pu egalement arriver par la voie des airs, profitant de circonstances climatiques favorables, sans compter la possibilite pour certaines d avoir derive sur des radeaux naturels, portes par les courants marins. on constate neanmoins, du fait de conditions d acces difficiles, une pauvrete relative du nombre d especes arrivees naturellement dans les iles de l actuelle polynesie francaise. une pauvrete cependant compensee par un endemisme qui fait que chaque ile se caracterise par des especes qui different les unes des autres par quelques > the history of birds in french polynesia is inseparable from the history of this insular environment and its relatively recent geology. spread out over an area as large as europe, the islands that make up the political entity of french polynesia are located 6 000 km away from the nearest continental masses : south america and australia. these volcanic islands, only a few million years old, have not experienced the long, hundred-million years history of life on continents. polynesians islands came out of the ocean at a time when all great plant and animal groups had already long appeared elsewhere. the former volcanoes, now above water, would still take millions of years to collect essentially airborne flora and fauna and allow their growth. physical factors such as winds come into play for the dispersion of pollen and seeds, even at great distances. small insects and spiders can also be lifted up to 1 000 meters and they probably were the first inhabitants of polynesian islands, riding accelerating winds during cyclones and hurricanes. this was also the case for seabirds that are not afraid of great distances. smaller species too may have arrived in the same manner, taking advantage of favorable climatic conditions, or even drifting on natural rafts borne by sea currents. however, because access to the islands is so difficult, the number of species that arrived naturally in french polynesia is quite low. this apparent scarcity is compensated by endemism, which makes species vary from island to island by only a few morphological characteristics. those variations are the result, among other things, of the specific food that can be found on each island, or of the lack of predatory mammals. >
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