started slightly before 12,300 B.P., followed by a major retreat. No large re-advance of the inland ice occurred during the Younger Dryas. However, in the Sunnmøre–Nordfjord area many local glaciers formed outside the inland ice during the Younger Dryas. Limnic sediments outside one such cirque glacier have been cored and dated, proving that the glacier did not exist at 12,300–11,000 B.P., and that it was formed and disappeared in the time interval 11,000–10,000 B.P. (Younger Dryas). The erosion rate of the cirque glacier was 0.9 mm/year. Flora and fauna Western Norway has similar flora and fauna as the rest of Norway, but there are some major differences. While almost all red deer in Norway are found here, there are few moose. Reindeer are a common sight on the Hardangervidda and in other large mountain areas. The whole of the Hardangervidda is above the tree line. Its alpine climate means that many species of Arctic animals and plants are found here, further south than anywhere else in Europe. Its wild reindeer herds are among the largest in the world, with some 15,000 animals recorded in 1996 and about 8,000 in 2008. They migrate across the plateau during the year, moving from their winter grazing lands on the east side of the Hardangervidda, where they graze on lichen, to their breeding grounds in the more fertile west of the plateau. 30,000 years ago glaciers covered vast areas of the Northern Hemisphere. As so much water was trapped on land, in the form of glacial ice, the sea lay 120 metres below its present level. This meant that the North Sea was dry land, a treeless tundra, with long, winding rivers, endless stretches of boggy land and wide, sandy heaths. Only as far south as the Mediterranean and the Black Sea were there any forests. As the climate slowly improved and the Scandinavian peninsula rose from the grip of the ice, plants and animals started to invade the new territory. As soon as there was dry land the first plants took root and with them came animals, birds and insects. The first of these were the Arctic animals such as wild reindeer, Arctic fox and wolverine (glutton), who followed the edge of the glacier up to the mountains. The trees came later, accompanied by a rich flora and fauna including bears, elk, marten, fox, hare, European beaver and otter. This influx reached its