Natural Features of Linnansaari National Park
Slash-and-burn Agriculture and Management of Traditional Landscape in Linnansaari
Abundance of Plant and Animal Species in Linnansaari
The Kingdom of the Osprey
Extremely Rare Species of Beetle Living in Eastern Finland
The National Park is a 40 km long and 5 - 10 km wide area in the middle of Lake Haukivesi, a part of Lake Saimaa which is the largest lake in Finland. The landscape alternates between a labyrinth of sheltered islands and broader open waters. The park includes more than 130 islands and hundreds of smaller islets and protruding rocks.
If you are lucky, you can see the endearing Saimaa Ringed Seal (www.metsa.fi, in Finnish) on the lake. Linnansaari is one of the best habitats of the Saimaa Ringed Seal (Phoca hispida saimensis). There are ca. 60 individuals which are faithful to their native place.
In Linnansaari, the deciduous forests, the bare rocks parched by the sun, and the open meadows offer a good habitat for many plant and animal species which have become rare. For example, Linnansaari is home for the endangered White-backed Woodpecker (Dendrocopos leucotos). There are great contrasts in the vegetation of the islands; looking from the lake towards the shore you can see the barren rocks covered in lichen, but lush groves hide behind them. Linnansaari has more herb-rich forests than any other National Park in Finland, about 30%. In Finland, herb-rich forests make up about 1% of all the forests.
The forests of the Park are young; the old-growth tree stands are mainly in the rock forests. This is because of the slash-and-burn agriculture and the loggings of the last century. The deciduous forests are dominated by the Birch (Betula) or the Aspen (Populus tremula), and in the younger forests the Alder (Alnus). One of the valuable features in the herb-rich forests is their diversity of tree species. In the same grove you can find the Birch, the Aspen, the Littleleaf Linden (Tilia cordata), the Hoary Alder (Alnus incana), the Pine (Pinus sylvestris), the Spruce (Picea), the Rowan (Sorbus aucuparia) and the Goat Willow (Salix caprea).
Eastern Finland was the last area where slash-and-burn agriculture was practised in Finland. It is known that on the main island (Linnansaari Island) burning-over of woodland for cultivation began already in the 1500s, centuries before the first permanent inhabitants settled into the area. The slash-and-burn agriculture ended in the 1930s, but in the summer 1993 it was started again. The goal is to clear and burn-over a small plot of land every year in the surroundings of Linnansaari Croft
Threatened Species Benefit from Slash-and-burn Agriculture
Slash-and-burn agriculture has a strong impact on both the landscape and the set of species living in it. Like natural forest fires, it creates clearings and deciduous forests at different stages of development. Supposedly in the end of 1800s all the spruce forests of Linnansaari had been cleared and burned-over, and the landscape was dominated by deciduous forests of different age.
The deciduous forests, and the meadows maintained after clearing and burning-over, offered habitats for many species which are nowadays threatened. The White-backed Woodpecker (Dendrocopos leucotos) is the most famous inhabitant of deciduous forests, but in the same forests live many other threatened species. During the time of the traditional ways of land use, the set of species living in the Finnish nature has been at its richest and most diverse. The light deciduous forests created by slash-and-burn agriculture have decreased due to the natural succession of forests and especially since planting of spruce and pine. In the management of Linnansaari, special attention has been paid to maintaining the deciduous forests. That is why sheep pasture again on the islands of the park. Also spruces have been cut from the ageing deciduous forests.
Groves and Shores
The diverse and demanding set of species makes the herb-rich forests valuable areas in the conservation of nature. For example the Aspen (Populus tremula) is the only edible food for tens of species of insects. In addition, many caterpillars, for example of the Tau Emperor (Aglia tau), the Catocala adultera and the Lime Hawk-moth (Mimas tiliae), live only on the deciduous trees or the plants of herb-rich forests. In the herb-rich forests are also found these rarities: the Broad-leaved Helleborine (Epipactis helleborine), the Bird's-Nest Orchid (Neottia nidus-avis) and the Ghost Orchid (Epipogium aphyllum).
On the shores of Linnansaari grows the demanding Hemp Agrimony (Eupatorium cannabinum). On the former fields and meadows you can find the Fragrant Orchid (Gymnadenia conopsea) and the Bristly Bellflower (Campanula cervicaria) On the shores flourish the Blister Sedge (Carex vesicaria) the Tufted Loosestrife (Lysimachia thyrsiflora) and the Paleyellow Iris (Iris pseudacorus).
Butterflies and Moths in Linnansaari
In the National Park, 346 Macrolepidoptera species have been found, which is almost a half of all the species found in Finland. The diversity of natural features in the inland archipelago makes an ideal environment for butterflies and moths in the lush aspen groves, bare rocks and the old meadows and clearings created by the slash-and-burn agriculture. The species include the threatened Chequered Blue (Scolitantides orion), and the rare Scarce Fritillary (Euphydryas maturna), the Baptria tibiale, the Dotted Carpet (Alcis jubatus) and the Trichosea ludifica. These species have become rare, since cattle no more grazes in the forest keeping open the small clearings where the butterflies and moths live.
The Majestic Osprey
Gliding over the open waters of Lake Saimaa, the Osprey (Pandion haliaetus) is a majestic sight. The Osprey is one of the biggest birds of prey in Finland, and Linnansaari has one of the densest osprey populations in the country. Ospreys nest in the staunch tops of the shoreline pines. In the large twig nests they usually have 1 - 3 young birds. The osprey is very skilful in search of prey. Shallow lakes with clear water are ideal places for them to be able to see the fish. It is amazing to watch how they dive on their prey and take off again with fish in their talons.
The osprey migrates to warm Africa for the winter. It can fly as far as to South-Africa, which makes a 12,500 km journey! Faithful to its native place, the osprey returns to the same area every year. The first brood they usually have at the age of three years. The osprey couples stay together all of their life.
The number of White-backed Woodpecker (Dendrocopos leucotos), which, inhabits areas at Linnansaari goes down to a very few. It likes to live in old, open deciduous forests, where it finds larvae in the rotten trees. The White-backed Woodpecker needs a lot of dead deciduous trees to be able to get enough food. Because of the active conservation measures, the population of the White-backed Woodpecker has grown.
Other Birds of the Inland Archipelago
In the National Park it is also possible to see the threatened Lesser Black-backed Gull (Larus fuscus), the Black-throated Diver (Gavia arctica) and the Northern Hobby (Falco subbuteo). In the waters swim the Goosander (Mergus merganser) and the Red-breasted Merganser (Mergus serrator). In the lush deciduous forests sing the Blackbird (Turdus merula), the Winter Wren (Troglodytes troglodytes), the Wood Warbler (Phylloscopus sibilatrix), the Greenish Warbler (Phylloscopus trochiloides) and the Common Rosefinch (Carpodacus erythrinus).
An extremely rare occurrence of Aulonothroscus laticollis was found in the Linnansaari National Park in Rantasalmi during a survey of species in herb-rich forests. This species has been sighted only once before in Finland, in 1865. The Aulonothroscus laticollis is very rare on a global scale as well, with only a few observations made in Poland, Croatia, France, Sweden and Russian Karelia. In Finland, this species is listed as critically endangered, which is the highest threat category.
The Aulonothroscus laticollis is a species of beetle included in the family Throscidae, and it is about four millimetres long. The habits of this species are not known with certainty due to its rarity, but observations suggest that it lives in tree litter forming in the cavities of hollow deciduous trees. The beetle probably feeds on fungal mycelia growing in the litter in the cavities.
A total of ten beetles were found in the aspen-dominated herb-rich forests of Linnansaari. They were encountered in window traps placed on the trunks of hollow living aspens. The population seems viable, but it is concentrated in a small area in herb-rich forests in the southern part of Linnansaari. No sightings of the Aulonothroscus laticollis have been made in subsequent surveys in other areas. Linnansaari National Park boasts an exceptional number of threatened and declining forest beetle species. This shows how valuable the area is for the conservation of species found in old-growth deciduous forests.
The species surveys conducted by the Natural Heritage Services of Metsähallitus are part of the Forest Biodiversity Programme for Southern Finland (METSO). Species data are needed to support planning the management and use of protected areas, as well as to monitor changes in the distribution of species and assess their threat status.
Linnansaari National Park
- Established 1956 Publications of Linnansaari National Park
- Area 97 km² (https://julkaisut.metsa.fi/julkaisut?Text=linnansaari)
The Emblem of Linnansaari National Park is Saimaa Ringed Seal