Many demanding northern species inhabit the Käsivarsi Wilderness Area, including the Norwegian lemming (Lemmus lemmus), the gyrfalcon (Falco rusticolus), the snowy owl (Bubo scandiacus) and the Arctic fox (Vulpes lagopus). The cold and inhospitable environment offers scarce opportunities for subsistence, making its fauna few in number. An exception are the peaks in lemming and other small rodent populations, during which the number of individual animals grows significantly.
The abundance of species varies from year to year. The size of lemming and other cricetid rodent populations varies in cycles of roughly four to five years. In peak years, their predators, including the red fox (Vulpes vulpes), the stoat (Mustela erminea), the rough-legged buzzard (Buteo lagopus), the short-eared owl (Asio flammeus) and the long-tailed jaeger (Stercorarius longicaudus), also grow in numbers. The mountain birch groves surrounding the village of Kilpisjärvi are home to an abundance of bluethroats (Luscinia svecica), and you can also come across the mountain hare (Lepus timidus). With luck, you may encounter a wolverine (Gulo gulo) in the Kilpisjärvi wilderness, while reindeer (Rangifer tarandus) are permanent residents of the area.
Demanding salmonoids, including the Arctic char (Salvelinus alpinus), the brown trout (Salmo trutta) and the European whitefish (Coregonus lavaretus), thrive in the oxygen-rich waters of the fells. Other species occurring in Lake Kilpisjärvi include the alpine bullhead (Cottus poecilopus), the burbot (Lota lota), the grayling (Thymallus thymallus) and the Eurasian minnow (Phoxinus phoxinus). The highest fells in the area are home to many butterfly species that in their juvenile forms eat specific mountain plants only. For example, the Arctia alpina moth is found in Finland only in the fells of the Käsivarsi Wilderness Area.
List of species:
The growing season in the Kilpisjärvi region is short, roughly only 100 days. Snow persists long into May, and the ice in Lake Kilpisjärvi breaks up only in June. The regional flora is nevertheless surprisingly diverse, and the unique conditions make them very distinctive. With chalky soil in places, the region is rich in calcicole plants and mosses, that is, species that prefer calcium-rich substrates. Late-melting snow beds create a special mosaic of different growth conditions in the landscape. Kilpisjärvi is located fewer than 50 kilometres from the Arctic Ocean, whose effect can also be seen in the species of the region. Many of the rare plants found in the area are protected.
Ranging up to 600–700 metres, the mountain birch groves give way to treeless fell tops, the dominant vegetation zone in the Käsivarsi Wilderness Area. Plants typical in these conditions are small and low, which effectively protects them from wind and the cold. For example, the endangered glacier buttercup (Ranunculus glacialis) grows along the meltwater streams of the mid- and upper fell tops and in late-melting snow beds. It has adapted to extreme conditions, holding records for both the highest growth site and the northernmost occurrence.
The Lapland rhododendron (Rhododendron lapponicum) is a low, evergreen dwarf shrub that blooms with beautiful purple flowers in the spring. It grows on fell slopes and dry sandy soils in northern Finland. The plant withstands cold well and is a rare, protected species that represents the special features of the fell environment.
The area around Lake Kilpisjärvi is unique from a geological perspective. Here ancient Finnish bedrock, over 2.8 billion years old, encounters the relatively young Scandinavian Mountains, aged only 400 to 600 million years. The young bedrock contains crumbly calcareous dolomite, which affects the regional flora and, consequently, the fauna. The most common rock type in the area is granodiorite, in addition to which the bedrock also contains plenty of granite and granite gneiss.
The Käsivarsi landscape is dominated by high fells, including Saana (Sána, 1,029 m MSL) and Halti (Háldi). On the slope of one of the sub-peaks of Halti is the highest point in Finland at 1,328 m MSL. The high fells were created during the folding of the Scandinavian Mountains. Later faults, uplifts and erosion in the land have further increased the relative altitudes.
Trace fossils have been preserved in places where the mountain-forming forces have not destroyed the original sediment structure. These fossils are records of the oldest known animal activity on Earth. The trace fossils found in the Saana region date back roughly 540 million years.
Kilpisjärvi has a distinctly oceanic climate affected by its northern location and altitude. The village of Kilpisjärvi is located roughly 500 metres above sea level and less than 50 kilometres from the Arctic Ocean. The proximity of the sea causes rapid changes in the weather, and the local climate is fairly arctic with an average annual temperature of only about -2.3 °C.
Permanent snow cover arrives usually in October, and the snow will not melt until May or June. In some summers, all-year patches of snow can be found on the fell slopes. At times, the proximity of the Arctic Ocean causes abundant winter rains, and the highest snow depth in Finland has been observed in the region’s fells.
The Kilpisjärvi Science Trails open a unique window to local wildlife. Along the trails, you get to explore the cleanest air in the world, the effect of mountain birch groves on cloud formation, and the benefits of reindeer grazing. A free mobile app will guide you whether you are walking in the rugged landscape or relaxing at home – discover the secrets of Kilpisjärvi’s nature and wildlife through the science trails!