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Skovleendene blir kalt så, fordi de ofte løper bortover vannflaten, idet de slår med vingene som en gammel hjuldampers skovler. Den hyppigste av dem i Tierra del Fuego, Patagoniaskovleand , Tachyeres patachonicus, er muligens en slektning til den ikke-flyvende Chileskovleand, Tachyeres pteneres, i Tierra del Fuego, og Falklandsskovleand, Tachyeres brachypterus, på Falklandsøyene. Tachyeres patachonicus Patagoniaskovleand Flying Steamerduck ![]() ![]() Patagoniaskovleand, Tachyeres patachonicus. I Chile kalles den 'Quetru volador' Photo: © http://www.arthurgrosset.com Patagoniaskovleanden finnes, som navnet tilsier, helt syd i Argentina, i Tierra del Fuego og på Falklandsøyene. På engelsk kalles de 'Flying Steamer-duck', flygende damp-ender. De kalles slik fordi de 'steamer' rundt i vannet idet de bruker føttene til til framdrift, og vingene som en slags plaskende tilleggsmotor. Dette er den eneste skovleanden som finnes i ferskvann, slik som her i Torres del Paine i Chile. ![]() Photo: © http://www.arthurgrosset.com Et annet interessant trekk ved pategoniaskovleanden er at den vanligvis viser en lang opprettet hale når den svømmer. Det er riktignok ikke bestandig så lett å se i kjølvannet av selve fuglen. Ellers hører fuglen til de mere agressive, og gjør en iherdig innsats for å forsvare sitt territorium. Tekst: : © http://www.arthurgrosset.com ------- Patagoniaskovleanden kan nå opp i 25 km i timen på sin vei over vannet, og den skal være sett over en strekning på 1 kilometer uten stopp. Denne adferd brukes både for å unnslippe farer og for å avmerke territoritale grenser.. Det engelske navnet 'steamer' stammer fra de første sjømennenes observasjoner på 16-1700 tallet, der de sammenlignet skovlingen med hjulene på en hjuldamper. "Mechanics of Steaming in Steamer-ducks" by Livezey & Humphrey in Auk, April 1983. Tachyeres pteneres Chileskovleand Flightless Steamerduck ![]() Note the spurs on the wing on the bird on the photo. The orange bumps on the wing are typical of both steamer-ducks, they are modified spurs used in fights. They are often dull and worn down in flightless, and much more pointed and slimmer in flying. Photo: © www.arthurgrosset.com ![]() Photo: © www.arthurgrosset.com ![]() Patagoniaskovleandk, Ushuaia, Tierra del Fuego. Tachyeres leucocephalus Hvithodeskovleand White-headed Steamerduck The Chubut Steamer Duck or White-headed Flightless Steamer Duck (Tachyeres leucocephalus) is a flightless duck endemic to Argentina. It
is the most recently recognized species of steamer duck, being described
only in 1981. This is because it is only found along a rather small
and sparsely populated stretch of coast around the Golfo San Jorge
in southern Chubut and northern Santa Cruz Provinces, and because
steamer ducks in general look fairly similar in plumage. It is now known to have a larger range, with occasional signtings along the coastline from the Valdes Peninsula to the Beagle Channel in Tierra del Fuego. The population may not exceed 5,000 birds, and a recent census on the coast of Chubut province recorded a maximum of 4,000 individuals, with key populations at Bahía San Gregorio, Bahía Melo and Caleta Malaspina, all located at northern San Jorge Gulf. The population is thought to be stable4. It appears to occur at very low densities throughout its range. It is entirely coastal in rocky areas and sheltered bays, breeding on offshore islands and peninsulas. IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4. <www.iucnredlist.org>. Downloaded on 02 November 2010 Tachyeres brachypterus Falklandsskovleand Falkland Steamerduck Weibliche Falkland-Dampfschiffente ![]() Falklandsskovleand, Gypsy Cove, Falkland Islands The Falkland Steamer Duck, Tachyeres brachypterus, is a steamer duck native to the Falkland Islands in the southern Atlantic Ocean. It is one of only two bird species to be endemic to the Falkland Islands (Islas Malvinas in Spanish), the other being Cobb's Wren. ![]() Female Falkland Flightless Steamer Duck, Tachyeres brachypterus at Port Stanley. Photo Pismire http://en.wikipedia.org/wiki/File:Tachyeres_brachypterus.jpg The Falkland Steamer Duck's wings are very short (hence the scientific
name: brachy = "short", and pteron = "wing"), coast except steep cliffs. Each pair holds a territory comprising of a set length of coastline which it guards vigorously. Nests are built behind the shoreline with 5 - 10 eggs being laid during September to December. Young fledge in January to March. Food is mostly shellfish and other marine invertebrates which it collects by dabbling or diving. |