ETUSIVU

UUSIN LEHTI

ARKISTO

TILAAJAPALVELU

TOIMITUS

MEDIAKORTTI
Suomen Luonto
English summaries 10/2003

Latvia on a watershed
by Antti Halkka
Pages 4?13

A couple of hundred kilometres away from Tallinn lies Latvia which, as of next May will be part of the new Europe, the Union. Over 11,000 white storks nest in Latvia, three times more than in Estonia. Latvia and Poland are the EU?s new major ?white stork countries?. In eastern Europe the mosaic of countryside and wetlands required by these birds remains well preserved.

Latvia joins the EU at the same time as the storks click their beaks together in the time-honoured rituals preceding mating. With the exception of a couple of strips belonging to Russia, the new EU will be responsible for the entire Baltic coast. In Latvia alone there are five hundred or so kilometres of coastline.

Latvia?s has a sandy coast, with sandstone rock in some places. There is none of the limestone dominating Estonia. Marine islands form with difficulty from sand and there are thus none in Latvia. By contrast, Estonia encloses around a thousand marine islands. The familiar Finnish bedrock (of great age) dips below Estonia and Latvia to a depth of over five hundred metres, and by the time you reach Lithuania, it is a kilometre and a half below you.

At the roadside lies a road accident victim in the form of an eastern hedgehog (Erinaceus concolor), an east European cousin of our own hedgehog. Latvia?s mammalian fauna is in general more southerly than that of Estonia. For instance, Latvia is well endowed with dormice, as many as four species of these animals inhabiting the country. These are the edible (Glis glis), forest (Dryomys nitedula), garden (Eliomys quercinus) and common, (Muscardinus avellanarius) dormouse. They spend the winter in hibernation.

Almost half of Latvia is covered by forest, part of which has sprung up on abandoned pastures and fields. Pine, birch and spruce are the dominant tree species, but there are many more Central European broadleaves than in Finland. In Latvian folk lore, the oak is a man and the lime a woman.

In Gauja National Park a river has gouged out a canyon in the limestone. This Central European type of national park also encloses fields and roads, but above all it protects irreplaceable indigenous wildlife and habitats. We take a look at one forest where the secretive black stork nests. This stork breeds in shady woodlands, where it builds nests weighing up to a ton in the sturdiest of trees. With about a thousand pairs today, Latvia is one of the most important strongholds of this endangered species. For Europe, the wet primeval forests of the Baltic states are possibly the most important of all their habitats. Although some still remain, they are constantly shrinking as Latvia undergoes change.

Kemeri National Park is a paradise for woodpeckers. Its most regal species is the middle spotted woodpecker. The park is also the home of the white-backed, lesser spotted, great spotted, three-toed, black, and grey-headed, woodpeckers. In many places the banks of the River Lielupe, which borders the national park, are occupied by common alder woodland. Some of the forests have been inundated by European beavers, of which there are 400-600 within the national park area.

The most splendid sandy beach flanks the Kolka peninsula in the most northern part of Latvia. A lighthouse now in Sliter National Park has been restored as a tourist sight and the park?s visitor centre. From the top one can see the shore of Saaremaa island, which is in Estonian territory. Frequently, too, the visitor can hear the howling of wolves, as the area is one of Latvia?s strongholds of the species. There are now several hundred of these mammals in the country.


In the virgin forests of White Sea Karelia
by Markus Sirkka
pages 36?41

Following a tough struggle, Kalevala National Park is finally to be established close to the most famous of the ?poetry villages? of White Sea Karelia. Naturalists and backpackers from Finland and the west eagerly await a paradise of old-growth forests behind the eastern border. People in the villages speak a lovely Karelian language that is similar to Finnish so that even Finns with a poor grasp of Russian will be able to communicate with the local populace. Villagers tend to ask backpackers why they bother to walk in the woods. Walking without purpose is what weird folk do; there is always a sound reason for setting off into a forest! There are no western trendy hi-tech facilities here; a few strips of fish, some salt and bread, is all a local person carries into the wilds. The rest of the food - mushrooms, berries, fish and game - is obtained, depending on the season, from the forest.

Kalevala?s forests are unique old-growth forest, composed in places of 300-500 year-old ?primeval? stands. The coming national park encloses approximately 74,000 ha of wilderness chequered with lakes west of the villages of Vuokkiniemi and Vuonninen adjacent to the Finnish border. This area forms part of the planned Green Belt chain, a chain of protected areas stretching on both sides of the border from the Gulf of Finland to the Arctic Ocean.

Fire scars on old Scots pines everywhere are a sign of repeated natural forest fires; in places these pines are so large that many people?s arms cannot reach right round their trunks. It is easy to hide among such giants. Spruce tends to grow along wet areas flanking streams and brooks, but otherwise the Scots pine is the dominant tree species. There are also many broadleaves, including aspen, birches, and grey willow.

In these old forests, the most western part of its breeding range, the black kite hunts for its prey. Here, too, one finds both white-tailed and golden eagles, as well as the great predators. The tracks of wolverine, wolf and wild forest reindeer are imprinted in the winter snows right next to the villages.
Signs of human impact are visible in the forest. There are no large clearcuts near the villages, but trees have been removed singly. Wilderness farms once occupied space by the rivers, their former meadows apparent even today, as some of them continue to be cut for hay. Bark has been stripped off birch trees here and there to meet local handiwork needs.

The national park notion enjoys the full support of local officials and inhabitants. Local folk do not benefit from logging, because the lumberjacks come either from elsewhere in Russia, or from abroad, most often from Finland. The matter of the establishment of the national park has now gone to Moscow for approval and a decision is expected later this year. Many hikers and naturalists fervently hope that the park will remain as wild as possible. However, the Russians want to develop tourism which will respect the national park and its wildlife while bringing work and prosperity to the local people as well.

The Karelian villages of the White Sea region and the forests surrounding them are important to the Finnish culture and identity. It was from here that the national poetry was gathered in the 19th century and here, too, that Elias Lönnrot?s idea of collecting The Kalevala into a single folk epic was born as he listened to the rune singers of Vuonninen village.


Saimaa?s land-locked lake salmon could be saved
by Jarmo Pasanen
Page 17

A survival strategy has been prepared for the Lake Saimaa salmon. This fish has become extinct in the wild, its population now being entirely dependent on fish farming and stocking. An effort is now being made to preserve the Lake Saimaa salmon?s gene pool by replacing brood fish and endeavouring to achieve natural fry production in the original spawning grounds. The population crashed in the 1960s when the rivers in which it normally spawned were harnessed for electricity generation.

Some 28,000 kilos of Lake Saimaa salmon a year are removed, which is too much for stocking to compensate. Mostly the salmon are caught on trolling spoons, although many also end up in vendace nets. The intention is to control fishing in cooperation with the Saimaa fishery areas. The legal catch size will be raised from 40 cm to 60 cm. A minimum mesh size will be specified by the new regulations, as also a maximum of six trolling rods per boat at any one time.


Can verges bring our meadows back?
by Alice Karlsson
Pages 62?65

Professor of agroecology Juha Helenius says it would be feasible to replace Finland?s lost flowering meadows by ditch banks and verges. In this context he also means the strips and buffer zones that are left between waterways and fields. These serve to reduce the amount of nutrients leaching into aquatic habitats.

In Finland underground drainage using plastic piping started as early as in the 1960s. Although systematic drainage using brick piping in fact dates from the 19th century, farmers generally retained their open ditches. By the 1930s only three percent of the field area had underground drainage. Nowadays 1.5 million hectares are drained by his method, amounting to 60 % of the total field area.

The European Union became aware of this kind of habitat?s vanishing flora and has taken steps to reverse the process. It began to offer support for the establishment and management of various kinds of banks and verges and in 1995 prohibited the spreading of pesticides and fertilisers in such areas. The results are apparent: some of the originally high level of biodiversity has been restored.

Finland has something like half a million kilometres of 3-metre wide verges acting as buffer zones. This amounts to 150,000 hectares, roughly the size of the province of Åland (Ahvenanmaa). However, the width is more important that the length. A more sensible width would be five metres.
The significance of buffer zones, at least at present, is only slight, however. Even though the zones tend to be wide (at least 15 m), there are few of them around. According to the Ministry of Agriculture and Forestry there are some 2,100 buffer zone agreements, plus 550 which have been applied for. The ones already formed amount to 5,500 ha, the new ones adding a further 2,000 ha.

Meadows are poor in nutrients, whereas the edges of cultivated fields are fertile. There would have to be forced reduction in fertility in buffer zones and verges in general by cutting the hay and taking it away. However, it is difficult to work on a narrow strip of land, neither is it possible to keep cattle on such an area. While cattle can be kept on a wider buffer zone, these means fencing off the field. Soft field edges pose a risk of animals getting stuck in the mud and ending up in the waterway.


Preparing for an oil spill
by Antti Halkka
Pages 14?15

In Helsinki an exercise has been carried out to see how an oil catastrophe could be brought under control using the Baltex-delta technique. Over 30 small and large vessels recently took part in a fictitious oil spill mop-up. These included the ice breaker Sisu, as well as vessels from the Finnish navy.
Oil is scooped from the sea and deposited in the holds of oil pollution control vessels. Mechanical oil pollution control is the most important technique for the Baltic says the protection commission?s secretary-general Anne Christine Brusendorff. Dispersants - substances breaking down the oil while it is in the water - are toxic and their use is not recommended. In Finland they are not even kept in store.

20 million tons of oil were transported across the Gulf of Finland in 1990, and 65 million in 2002. By 2005 over 100 million tons will be making their way across the Baltic. At the same time there will be a dramatic increase in the amount of marine cargo and passenger transport. Next summer a new marine transport control and guidance system is to be introduced. In addition, captains will be obliged to notify the authorities that their ships are entering international waters in the Gulf of Finland.

The Baltex-delta exercise succeeded well. The international ?fleet? gathered 1,500 tons of oil. However, an accident of this kind is so huge that in actuality cleaning up after the oil spill could easily take months, if not years. More vessels are urgently needed. Tankers of the 100,000-150,000 ton class serve the new oil harbour at Koivisto. The Exxon Valdes released 40,000 tons of oil on to the coast of Alaska, the Globe Asim (during the Baltic?s largest peacetime catastrophe) 16,000 tons in our area. Should another vessel crash into the side of one coming from Koivisto, hitting it between the storage tanks, some 30,000 tons of oil could leak out into the sea. In theory this would be enough to pollute the entire Gulf of Finland.


Ask us about nature! Readers? queries to the magazine?s experts:

Do eagles follow cranes on their migratory flights?
Two golden eagles were gliding along above a flock of migrating cranes. Do eagles use the cranes as a food source or for navigation purposes?

Seppo Vuolanto: An eagle is able to prey on half-grown cranes and will occasionally attack an injured adult. However, eagles never attempt to catch flying birds. Thus, the eagles have no chance of eating one of the cranes unless it is ill or injured after flying into a power cable, for example.
Cranes generally leave Finland in a southerly-northerly direction. Eagles migrate in a far wider variety of directions. Ringed birds that have been found indicate that young eagles tend to follow the ?geography? of the land, keeping to a coastline for instance, whereas cranes migrate in a straight line.

Eagles and cranes make use of thermals in the same way as gliders. These occur in places where the sun has warmed the land more than it has the rest of the environment. One can often observe many different kinds of birds circling over the same point. This explains the reader?s observation.

In there enough food available in the air?
How do all the swallows and martins flying in the air get enough food? How many insects are there flying?

Kauri Mikkola: An interesting question!. No assessments have actually been made in Finland as regards the total insect biomass in the air. Neither have any calculations been made regarding the adequacy of insects from the viewpoint of swifts, swallows and martins. The food of swifts has been determined by taking balls of insects brought to nestlings by the parents and examining these.

The amount of insects in the air varies according to the season and weather. From April to October, whenever the weather is favourable, large numbers of insects take to the wing from meadows and other warm spots. They start flying in the morning. The most important reason for taking to the wing is the urge of young insects to disperse, to exhibit vagrancy. Rising thermals give them lift. Spiders are also borne aloft, gliding along with the aid of their silk. There is a living, mobile community at a height of up to 3-4 kilometres, conditions being too cold beyond this altitude.

Water bodies are an endless source of insect life. In the bottom mud vast numbers of chironomid midge, and other dipteron, larvae live, along with mayfly nymphs. On hatching, these insects swarm, sometimes in such numbers that they appear to form a dense fog. Swarming ants may also fill the air with insect food.

Insects present in the air may have local origins, or they may have travelled great distances. Especially those that have come from afar may be found in the air both day and night. Altogether the flying biomass is so large that there is no doubt at all of its ability to sustain swallows, martins and swifts in normal circumstances. When the weather is poor, the number of insects is reduced, however, to a fraction of normal.

Animals that predate in the air are opportunists well able to make the best of a good opportunity. During periods of low pressure, swallows and martins fly close to the water surface, where there is presumably the largest number of insects, especially newly hatched chironomids. Radar has sometimes shown swifts hunting for prey so high that rising insects must come to them as though on a tray, in a half frozen condition.

Teksti: Leigh Plester



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