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Suomen Luonto
English summaries 2/2003

Ringed seal makes its home on the ice
Text by Antti Halkka, pictures by Seppo Keränen
Pages 4-11

Researchers have observed the ringed seal as far north as on the North Pole, so that it is no wonder that even the severest winter has little effect on the animal. Ringed seals arrived here more than 10,000 years ago, as the continental glacier withdrew. They remained in the region, virtually imprisoned, as the climate warmed. Ringed seals are unable to survive in the southern part of the Baltic, the North Sea, or even along the northern coast of Norway, the sea in these areas being too warm for the species.

There are at least 6,000 ringed seals in the Baltic, 230-250 more in Lake Saimaa, and a few thousand in Lake Ladoga. The world's total population amounts to over 5 million. Finland has become the leading country in terms of both ringed seal research and photography.

Ringed seals have dwindled almost to the point of extinction in the south-western archipelago region, the Åland archipelago, and the western Baltic. Moreover, they have completely vanished from the southern part of Bothnian Sea and the western Gulf of Finland. The causes have been listed as over-hunting, environmental toxins (especially PCB compounds), neurotoxins produced by cyanophytes, and warm winters during which the ice the seals require for breeding has simply not formed.

In winter, ringed seals maintain a network of holes at the water surface through which they can obtain air. Propelled by its rear flippers, the seal bores a hole through the ice with the sturdy, sharp claws of its front flippers. In the North Pole these animals are able to keep a breathing hole open at the surface of two-metre thick ice.

Female seals give birth in a 'cave' hollowed out of the snow above one of these breathing holes in February or at the beginning of March. Snow is an effective insulator which protects the young pups from too much cold. The parent suckles her young for over a month, the pup growing rapidly because the milk it is given contains 38% fat and 10% protein. Pups stay with their mothers for some time after weaning.

Ringed seals are reluctant to leave their home grounds, so that they spread extremely slowly into areas where their populations have for some reason become extinct. Baltic ringed seals are currently suffering from environmental stresses, with one third of old females now sterile, as well as some young ones even. If our winters should become warmer, the effect on ringed seals will be devastating, since there will be no ice cover on the sea to answer their breeding needs. Fortunately, this has been a real 'ringed seal winter', with plenty of ice and a good covering of snow.


Yeti-sized footprints in the snow
By Ritva Kupari
Pages 18-21

Equipped with snowshoes, it is possible for any of us to hike in soft snow or on slippery ice. Big feet support one's weight and are less likely to lose their grip than Cinderella-sized ones. In Finland people have traditionally used skis to get about in winter, whereas snowshoes arrived here from North America as recently ago as the late 20th century. Now there are more than 50 snowshoe manufacturers in the world. Finland imports at least 25 different brands of this kind of footwear, which is used by around 100,000 enthusiasts.

Snowshoe walking not only forms a fine hobby and a means of keeping fit, but it can also be an aid to performing work. Professionals in forestry and other jobs connected directly with nature, researchers, photographers and electricians can get about on snowshoes even in difficult terrain blanketed by soft snow.

Poles or staffs are a recommended accessory when using snowshoes. They not only help people to keep upright, but also considerably increase the energy required for movement, thereby improving fitness. Walking on snowshoes consumes 40 percent more energy than ordinary walking. This is due to the weight of this footwear, the resistance of the snow, and the fact that the back, shoulders and arms are all brought into play in addition to the legs and hips.


'Voice of Nature' familiar to the public
By Juha Kauppinen
Pages 24-26

Every Finn knows Jarmo Heikkinen - or to be more exact, his voice, for Heikkinen is the man who speaks the commentaries to almost all of Finnish television's wildlife documentaries.

Heikkinen has lived outside Helsinki, in Espoo, right next to the forest, for the last 20 years. This is important to him. Should he 'bump into' an exceptionally old tree in the forest, he will stop and touch it. His summer house stands on the shore of Lake Lohjanjärvi, where he can see the forest and water twinkling between the trees.

Jarmo Heikkinen has been recording commentaries for wildlife films and TV documentaries since the early 1970s. He has mixed feelings about wildlife documentaries: on the one hand they help us conserve wildlife by showing people what we could lose unless we act responsibly, and on the other they are made in areas and about matters where film crews really have no business at all.

However, wildlife documentaries contain all the great elements of drama - birth and death, mating and fighting, says Heikkinen.


Belgian reserve composed of planted compartments
By Eero Haapanen
Pages 40-42

Heidebos is a 200-hectare nature reserve in Belgium. It also constitutes the largest forest within a radius of several tens of kilometres. The forest is composed of one-hectare, square compartments each containing only one species of conifer. The trees are in general small and in poor condition. Large beeches, maples and Northern red oaks are found only along avenues along the edges of the plantations. Young common alder and birch groves fringe the forest.

The nature conservation NGO Natuurpunt purchased the area and opened it to the public in 1997. The organisation has provided several kilometres of waymarked trails equipped with information boards. It intends altering the tree stands to make them more closely resemble the region?s indigenous forest.

Despite its artificiality, the forest is used by a wide variety of birds of prey for nesting, including buzzards, sparrow hawks, goshawks and honey buzzards, in addition to long-eared owls, Minerva's owls and barn owls. Among the mammals, the roe deer, weasel, stoat, polecat, red fox and red squirrel can be seen in the area.

Heidebos and other Natuurpunt reserves appear strange to Finns because there is no trace of indigenous habitats anywhere. Despite this, birds and many other animals seem to thrive in the artificial environment. Furthermore, the long term aim is to restore the areas' indigenous nature as fully as possible.


New-style living in Ekoviikki suburb
By Pekka Hänninen
Pages 62-65

A new suburb has sprung up in Helsinki's north-eastern quarter, Viikki. Here, too, Finland's first eco-town area is being built. While the idea of ecologically sensible living is laudable, many people are wondering whether this experimental community ought to be established in an area important for its birdlife.

Markku Mikkola-Roos, who has been studying the bird species of arable land in Viikki for many years, condemns the project. Houses not only cover a particularly good area for such species but they also destroy a seasonally flooded meadow where migrating whooper swans and bean geese habitually drop in to rest. By 2010 a university town will have been constructed in Viikki which will accommodate 6,000 employees and 6,000 students in addition to 13,000 residents.

The ecological residential area is to have a ribbon-type layout, with buildings and green belts alternating. This set-up will provide all residents with their own allotments, while solar energy is to be exploited in the dwellings. Glazed greenhouses and conservatories will also be included for the inhabitants.

A planning competition for the eco-area's first precinct was won by an entry emphasising a pollution-free environment, conservation of natural resources, and good health. Additionally, emphasis was laid on the conservation of biodiversity and the growing of food for personal consumption.

Apartment buildings in the area have been constructed from concrete elements in the conventional manner, mortar for the surface then being put on when the building is in place. The building commissioners have not sought to experiment with alternative construction methods, as this would have seriously increased the cost. On the other hand, the new row houses and detached houses have been constructed from wood, logs and even straw bales.

Perhaps the most important feature of the Viikki project is the harnessing of solar power, since this has so far only rarely been attempted for apartment buildings in Finland. Water for household use will be heated by solar power in two buildings out of three. Solar panels will generate 15 % of all the heating energy required by the dwellings.

Experts consider that Ekoviikki nowhere near represents perfect ecoliving. However, the construction costs have turned out to be only around five percent higher than normal. If it is possible to achieve such remarkable emission reductions and energy savings as cheaply as this, then the result cannot be bad.

Teksti: Leigh Plester



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