Lake Myvatn, Iceland HD

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• published: 20 Feb 2014
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Lake Myvatn, Iceland HD - Lake Myvatn travel and Tour World Travel https://www.youtube.com/user/World1Tube Mývatn is a shallow eutrophic lake situated in an area of active volcanism in the north of Iceland, not far from Krafla volcano. The lake and its surrounding wetlands have an exceptionally rich fauna of waterbirds, especially ducks. The lake was created by a large basaltic lava eruption 2300 years ago, and the surrounding landscape is dominated by volcanic landforms, including lava pillars and rootless vents (pseudocraters). The effluent river Laxá is known for its rich fishing for Brown Trout and Atlantic Salmon. The name of the lake (Icelandic mý ("midge") and vatn ("lake"); the lake of midges) comes from the huge numbers of midges to be found there in the summer. The name Mývatn is sometimes used not only for the lake but the whole surrounding inhabited area. The River Laxá, Lake Mývatn and the surrounding wetlands are protected as a nature reserve (the Mývatn-Laxá Nature Conservation Area). Since the year 2000, a marathon around the lake takes place in summer. Waterbirds Shore of Mývatn. The lake is fed by nutrient-rich springwater and has a high abundance of aquatic insects (Chironomidae) and Cladocera that form an attractive food supply for ducks. Thirteen species of ducks nest here. The duck species composition is unique in the mixture of Eurasian and North American elements and of boreal and arctic species. Most of the ducks are migratory, arriving in late April - early May from north-western Europe. The most abundant is the Tufted Duck, which immigrated to Iceland at the end of the 19th century. The Greater Scaup is the second most common duck species. Other common species include the Barrow's Goldeneye, Red-breasted Merganser, Wigeon, Gadwall, Mallard, Common Scoter, Long-tailed duck and Eurasian Teal. The outflowing Laxá river has a dense colony of Harlequin Ducks and there is a large colony of Eiders at the river mouth some 50 km away from Lake Mývatn. The Barrow's Goldeneye is special in being the only nearctic duck in the area (and Iceland as a whole). Its population of about 2000 birds relies entirely on the habitat provided by the Mývatn-Laxá water system and its surrounding lava fields. Most of the Barrow's Goldeneyes overwinter there, using ice-free areas kept open by emerging spring water (both warm and cold) and in the strong river current. This species is a hole-nester, in North America using tree-holes, but at Mývatn the birds use cavities in the lava for nesting. The other duck species nest abundantly in the numerous islands of the lake and the surrounding marshlands. There is a long tradition of harvesting duck eggs for home use on the local farms. To ensure sustainability, the harvesting follows strict age-old rules of leaving at least four eggs in a nest for the duck to incubate. Other common waterbirds include the Slavonian Grebe, Red-necked Phalarope, Great Northern Diver, Red-throated Diver and Whooper Swan. Volcanism Lake Mývatn was created about 2300 years ago by a large fissure eruption pouring out basaltic lava. The lava flowed down the Laxárdalur Valley to the lowland plain of Aðaldalur where it entered the Arctic Ocean about 50 km away from Mývatn. The Crater Row that was formed on top of the eruptive fissure is called Þrengslaborgir (or Lúdentarborgir) and has often been used as a textbook example of this type of volcanic activity. There was a large lake in the area at the time, a precursor of the present-day Mývatn. When the glowing lava encountered the lake some of the water-logged lake sediment was trapped underneath it. The ensuing steam explosions tore the lava into small pieces which were thrown up into the air, together with some of the lake. By repeated explosions in a number of locations, groups of craters built up and now dominate the landscape on the shore of Lake Mývatn and also form some of the islands in the lake. This type of lava formation is known as pseudocraters or rootless vents. A group of such craters at Skútustaðir on the south shore of the lake is protected as a natural monument and is frequented by tourists. Other pseudocrater groups in this lava field are in the Laxárdalur Valley and Aðaldalur. The formation of pseudocraters halted the advance of the lava in some places creating temporal lava lakes. The lava eventually drained from the lakes, leaving behind a forest of rock pillars. The biggest of these formations is named Dimmuborgir. At another place, Höfði, the pillars stand in the lake water. The lava created by the Þrengslaborgir eruption is known as the Younger Laxá Lava. The Mývatn district lies on the western border of the volcanic zone which cuts across north-eastern Iceland from north to south and is an extension of the Mid-Atlantic Ridge. All geological formations are quite recent, dating from the Ice Age and postglacial times.