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06-24-2010, 04:43 PM
Estonian Nature (http://www.einst.ee/publications/nature/)

The Nordic Latitude

A small country in Northern Europe with an area of 45 215.4 sq km, of which about one tenth (4133 sq km) is taken up by islands, Estonia forms the most western and maritime part of the large East-European Plain. Estonia’s territory comprises 0.03 per cent of the world’s land area, located between 57º30'34'' and 59º49'12'' N and between 21º45'49'' and 28º12'44'' E.

The high latitude makes the rotation of seasons and the interchange of light and dark periods of the year well pronounced in Estonia — the maximum length of a summer day on the north coast is 18 hours 14 minutes, whereas during the shortest day in winter the sun appears for a mere 6 hours 3 minutes. Moreover, the long twilight time makes the transition between day and night rather smooth and the nights around the Midsummer Day shorter still.

Warm Summers, Mild Winters

The climate in Estonia is determined by the country’s location at the northwestern reaches of the Eurasian continent and the proximity of the North Atlantic. In the same way, local climatic differences are due, above all, to the vicinity of the Baltic Sea. Thus, summer temperatures are somewhat lower than the average for the latitude, but winter temperatures are considerably warmer. The average temperature of the coldest month, February, is –3.5° to – 7 °C, that of the warmest, July, being 16 to 18°C.

Permanent snow cover becomes established in the southeast at the beginning of December, at the earliest; and by the end of March, the snow can be more than half a metre deep. Apart from the coast and the Western Islands, the snow cover lasts for approximately 100 days: from the beginning of January to the end of March. In mild winters, however, much of Estonia does not have lasting snow cover at all.

Because of the influence of the warm Gulf Stream, the prevailing winds in Estonia blow from the southwest and west. Severe weather conditions, such as tempests and whirlwinds, are rare: the last hurricane raged through Estonia in 1969.

Flat Countryside, Varied Landscapes

As a part of the East-European Plain, Estonia is characterised by a flat surface topography: over 60 per cent of the country’s territory lies at an absolute height of 0 to 50 metres and only one tenth has an elevation over 100 metres above sea level. Thus, the local scenery is rather poor in vertical majesty — as a rule, no topographic feature rises above its immediate vicinity by more than 20 metres and only seldom by more than 50 metres.

During the late glacial and post-glacial period, i.e. approximately 12 000–9 000 years ago, a considerable part of Estonia was flooded by the waters of the large ice-dammed lakes and the Baltic Sea. Much of the Western Estonian mainland and islands have emerged as a result of the gradual uplift of the earth’s crust. The process is still in progress: the northwestern part of Estonia is rising at an annual rate of 2.5 millimetres. Most of the land ‘won’ thus far, forms the so-called Lower Estonia which includes flat accumulative and marine plains, with occasional ridges of coastal dunes.

The central part of North Estonia is dominated by the creviced heights of the Pandivere Upland (highest point at 166 metres above sea level); the rest being taken up by a flat limestone plateau which is characterised by extensive alvars — dry areas with very thin or virtually absent soil cover over bedrock.

The northern edge of the plateau falls abruptly to the sea, forming a coastal cliff which stretches for kilometres along the southern shore of the Gulf of Finland. The highest point of the Baltic Clint is at Ontika in the northeast where the 56 metre high escarpment offers beautiful views of the sea.

The numerous bedrock scarps in the western part of the mainland and on the islands of Saaremaa and Muhu represent another limestone escarpment, the West-Estonian Clint.

While the most remarkable features of the country’s topography — the uplands, ancient valleys, depressions, and the Clint — were already formed before the advance of the glaciers, Estonia acquired the majority of its landforms through the movement of continental ice.

However, it is the Southeast which is both the highest and topographically most variegated region in Estonia. The undulating till plains of the Sakala Upland, the wooded moraine hills of the Otepää (217 m), Karula (137 m) and Haanja Heights with numerous lakes and rivers lend the scene picturesque mildness.

Surprising as it may sound, the 318 metres high Suur Munamägi (‘Great Egg Hill’) in the Haanja Upland, being the highest point of Estonia, is the highest point in all the Baltic countries as well.

Proximity to the Sea

The influence of the maritime location can be observed in virtually every aspect of Estonian nature. The country has 3794 km of coastline, 2540 km of it on the islands. The land border, in comparison, is mere 633 km, of which 339 km is shared with Latvia in the south and 294 km with Russia in the east.

The coast varies from the sheer limestone cliff in the North to sandy beaches and shelving coastal meadows in the West.

The majority of islands belong to the West Estonian Archipelago; the largest islands are Saaremaa (Ösel) with 2 671 sq km, Hiiumaa (Dagö) with 989 sq km and Muhu (Moon) with 200 sq km. The sea between these islands and the Mainland — Väinameri (‘sea of straits’) — is very shallow (less than five metres deep on average) and rich in shoals.

The water of the Baltic Sea is brackish: its average salinity (8 to 10 per mil) is only one fourth of that of the sea in general. As Estonia is situated far from the Danish Straits which operate as a sluice for salty ocean water, the salinity of its coastal waters is lower still: down to 4 per mil in Narva Bay at the eastern end of the Gulf of Finland. It is not surprising, therefore, that most Estonian freshwater fish (about 30 species) also inhabit the sea.

Such large bodies of brackish water are rather unique in the world and the Baltic Sea with its 373 000 sq km is the largest of them. As there are relatively few forms of life which have adapted to the brackish water, the Baltic is poor in number of species, but rich in number of the individuals, yielding almost 1 per cent of world’s annual fish catch. Estonian coastal waters are also very important reproduction and nursery areas for many fish species.

Because of the isolation from the ocean, the tides are virtually absent (less than 0.1 m) in the Baltic Sea. The fluctuation of the sea level (max. 2.5 m in Estonia) is due to the strong prevailing winds. The waves in the Baltic Sea are usually less than one metre high, but during extraordinary storms they may be up to 10 metres in the open sea.

The sea is warmest in July and August: 15 to 17°C away from the coast and up to 26°C in small, shallow bays.

The Väinameri and the Gulf of Pärnu start to freeze at the end of November; a lasting ice cover on the straits between the islands and the mainland is formed by mid January. The Gulf of Finland and the Livonian Bay freeze over only in exceptionally cold winters.

Lakes and Watercourses

There are some 1 450 natural and man-made lakes in Estonia (6.1 per cent of the nation’s territory). The two largest of them, Lake Peipsi (the fifth largest in Europe; 3 555 sq km, shared with Russia) and Võrtsjärv (270 sq. km) together make up 88.8 per cent of Estonia’s lake areas. Of all the other lakes, only 45 have an area of more than 100 ha.

The number of lakes is highest in the valleys of the South-East Uplands: Haanja, Otepää and Karula Heights have all more than 25 lakes per 100 sq km; among them the deepest, Rõuge Suurjärv (38 m). Another lake district can be found around Kurtna in the northeast, where there are as many as 41 lakes on 30 sq km.

Of the more than 7 000 rivers, streams and drainage ditches, which are divided between the basins of the Gulf of Finland, the Väinameri together with the Livonian Bay, and Lake Peipsi, only nine are over 100 km in length. The longest, at 162 km, is the Võhandu River in the southeast, followed by the Pärnu, Põltsamaa and Pedja rivers.

However, the average run-off of the short but wide Narva River which connects Lake Peipsi with the Gulf of Finland is greater than the average run-off of all other rivers combined.

The Northern Estonian rivers flowing into the Gulf of Finland form scenic waterfalls as they spill over the edge of the Clint, while rivers of South Estonia, such as the Võhandu, Ahja and Piusa, have cut themselves picturesque valleys with high outcrops of red sandstone.

Although lesser in extent than in most of Western and Central Europe, Estonia's natural stream network is still significantly altered as a result of amelioration. Larger rivers and streams have often been dredged and straightened.

Mosaic of Forests, Meadows and Marshes

Almost half of Estonian territory (47.6 per cent)(It's over 50% now, this article is a few years old.) is under forest and woodlands; the area of forest stands has more than doubled during the last 50 years and is still growing.

Estonia is situated on a border area where the coniferous Euro-Siberian taiga opens onto a European zone of deciduous forests. There are 87 native and more than 500 introduced tree and bush species recorded. Scots pine is the most common tree in Estonian woods — dominant in 41 per cent of forests, followed by birches (silver and downy birch) — 28 per cent, Norway spruce — 23 per cent, alders (grey and common alder) and aspen.

Forests and woodlands are not evenly distributed in Estonia. The largest forests can be found in the northeast and in Mid-Estonia — a zone stretching from the Northern coast to the Latvian border.

In many locations in Estonia, for instance in Hiiumaa and in the northeast, large tracks of primeval forests, a type long disappeared from most of Western Europe, have been preserved.

Owing to abundant precipitation and slight run-off, Estonia is rich in wetlands. There are some 165 000 marshes greater than one hectare in area, of which 132 peatlands are larger than 1000 ha. The total area of marshes and swamp forests measures 1 009 101 ha which is over one fifth (22.3 per cent) of the country’s territory. Only Estonia’s northern neighbour, Finland, has a higher percentage (31) of peatland.

Approximately two thirds of the marshes in Estonia began as lakes which were gradually turned into quagmires by the spreading shoreline vegetation. The rest of Estonian swamps were formed by an opposite process, the paludification of mineral land.

The oldest marshes have an age of about 10 000 years, more intensive paludification started 8 500-8 000 years ago, whereas the intensive terrestrialisation of lakes began only about 6 500 years ago.

Starting from nutrient rich fens and evolving through the transitional marshes, the development of a swamp finds its final form in a raised marsh, a bog — an amazingly autonomous and resilient ecosystem. A bog consists mainly of peat mosses (Sphagnum) which get all the minerals they need from precipitation and dust particles.

Plants — Ice-Age Relics Among the Newcomers

Estonia is traversed by an important European bio-geographical borderline which divides the area into two large provinces. The northern and western parts of the country with their characteristic calciphilous plant communities of alvars, fens, wooded meadows and broad-leaved forests belong to the Mid-European province while the East, where acid soils promote the development of acidophilous plants and pine as the main forest-forming tree, belongs to the East-European province. There are as many as 251 species of higher plants for which Estonia is the distribution limit, be it northern, southern, western or eastern.

The number of vascular plants growing in Estonia totals ca 1 400 (together with microspecies of some genera ca 1 600). Due to the milder climate of western Estonia, 3/4 of the total number of species are found in the coastal lowlands and islands. This also includes the only local endemic species — Saaremaa yellow rattle — which grows in the western part of the island of Saaremaa.

In spite of large tracks of intact nature, Estonian flora as a whole is under strong human attack. For instance, the vegetation of grasslands, varying from floodplain meadows on the riverbanks to the dry alvars, has been formed under a long-lasting and steady impact of haymaking and pasturing.

About one fourth of Estonian plant species are habitants of marshes. Owing to their stability as habitats, the bogs also contain many relict species that once colonised the tundra-like landscape which emerged from under the withdrawing ice. Of the forest-tundra plants, inhabiting Estonian bogs, the shrub-like dwarf birch and the cloudberry are most common.

Fungi are found in all natural and ruderal habitats of Estonia, being particularly widespread in forests, meadows and bogs. The best mushroom forests, where there can be found as many as 400 edible fungi, are situated in the north and southeastern Estonia, as well as in Saaremaa.

Estonian Fauna — Recent and Numerous

Estonian fauna is relatively young as it evolved only after the last glacial period. As in the case of flora, among the animals inhabiting Estonia there are many rare and endangered species, some of them relics of colder climatic periods of the past.

As in any other temporal climate, the largest number of species — 11 600 — is that of the invertebrates. Among them, it is insects which in their turn are the most abundant group with approximately 10 000 documented (and another 10 000 probable) species. In comparison 488 vertebrate animals have been found in Estonia, including eight introduced species.

It is difficult to divide the 65 species of fish living in Estonia into fresh-water and sea species, as most of them inhabit both the inland waters and the brackish coastal sea. In addition, there are a couple of species of sea-inhabiting salmonids which migrate to the rivers during the spawning-time. The number of Atlantic salt water species which have adapted to the low salinity of the Baltic Sea — i.e. the Baltic herring, the sprat, the flounder — is rather small. There are no endemic fish in Estonia and the sole arctic relic from the former phases of the Baltic Sea is the fourhorned sculpin.

Again, similarly to plants, many animals in Estonia are on the northern, southern, western, or eastern border of their area of propagation. This is the case with the majority of 11 species of amphibians recorded in Estonia. Some of them, like the common frog, the moor frog, the common toad, or the common newt are quite widespread, while others — the crested newt, the green toad, the natterjack, or the pool frog — are more rare and consequently under protection. The best habitats for amphibians in Estonia are, interestingly enough, a couple of small islands, like Ruhnu and Manilaid off the southwest coast and Piirissaar in Lake Peipsi, the latter having an estimated 40 kg of amphibians per one hectare.

Reptiles are represented by three species of lizards and two species of snakes in Estonia. Both of the most widely distributed species, the common lizard and the common viper, prefer moist environs — bogs, wet meadows and forests, and the proximity of water. The other species of snake, the grass snake, is most abundant in the more open and human-influenced landscape of the western mainland and the islands as well as the coast of the Gulf of Finland. The aforementioned reptiles, together with the snake-like blindworm and the still rarer sand lizard, have all been included in the list of protected species.

A Paradise for Migratory Birds

Birds were probably the first creatures to arrive in Estonia after the last glacial period. Since then, Estonia forms an important link in a migratory track of a variety of Arctic water birds flying every spring northwards to their nesting places and every autumn back to their southern wintering areas.

Of the 333 recorded bird species, 222 breed in Estonia (206 regularly), 35 being transit migrants, 4 winter visitors and 72 vagrants.

The majority of breeding bird species are migratory. Among the resident species which can survive the harsh winters, the capercaillie, black grouse, magpie, woodpeckers, tits, etc., are the most typical. The first migrating birds to arrive in March are the common starling, rook and northern lapwing; the last species, like reed warblers, do not reach Estonia before the second half of May.

It is during the period from the end of April to the beginning of July that the bird life in Estonia is at its peak. By August the first breeding birds start the journey back to the South. The autumn migration lasts, however, for much longer; during the milder winters some species can leave Estonia as late as December. Or not leave at all, which is the case with a growing number of once migratory species, e.g. the blackbird or the mute swan.

Forest species constitute about a half of Estonian birds. The richest in both the number of species and individuals are the broad-leaved deciduous and mixed forests, where the average density of breeding pairs varies from 550 to 1700 per sq. km. Forest birds are mainly passerines: finches, thrushes, warblers, robin, pipits, etc. Chaffinches and willow warblers are probably the most numerous birds in Estonia.

In spite of being relatively poor environmentally, bogs form one of the most interesting habitats for birds. Among the birds which find the bogs congenial as nesting places are some relic tundra species as the European golden plover and the whimbrel. Unfortunately, many typical tundra species, like the willow grouse, the peregrine falcon and the black-throated diver, which were all characteristic exhibits of Estonian bog wildlife, have disappeared as nesting birds during the last decades.

The indented seashore provides habitats for different groups of birds. Thus the waders make up more than half of the breeding birds of the salt marshes and coastal meadows. Another interesting community is the one amongst large reed plains on the western coast and islands where coots, bitterns, water rails, etc. are common.

It is the small islets and skerries, however, that can be called bird paradise. Undisturbed by man and protected from most smaller predators by the sea, they are real nesting sanctuaries for a diversity of gulls, terns, ducks and waders.

Due to the vast preserved natural landscapes, the swamplands in particular, large raptorial birds, such as the golden eagle, white-tailed eagle, osprey, spotted eagle and eagle owl have made Estonia their home. All together at least 400 pairs of eagles have been recorded. Another rare and very elusive bird species which inhabits the large forests is the black stork.

Thanks to the protective measures for both birds and their habitats, several species in decline in Western Europe have increased in number in Estonia, e.g. the corncrake and the white stork whose nests on old chimney stacks and telegraph poles are an inseparable part of the Estonian landscape in the summer.

Survivors from a Former Europe

Sixty-four species of mammals have been recorded in Estonia, three of them have been introduced: the racoon dog, the American mink and the muskrat. The European beaver, hunted to extinction by 1871, was reintroduced in 1950s and a vital population of about 9 000 animals exists once again in Estonia. Another reintroduced mammal is the red deer with a present population of about 1 100.

Estonia is the home of several rare mammals, the most endangered of them being the European mink, several species of dormouse and the flying squirrel. The latter has become a symbol of the primeval forest, the most important monument to Estonian nature.

Although not as many as 1 100, as estimated by over-enthusiastic hunters, there are still hundreds of lynx dwelling in the large forests of Estonia, together with 300 wolves, more than 500 brown bears and many more smaller carnivores. The disproportionally large number of predators, especially that of wolves, has recently caused serious damage to the population of both of the most numerous species of large mammals in Estonia, the roe deer and the wild boar, as well as the elk.

Several islets in the Väinameri and on the western coast of Saaremaa are important whelping grounds for Baltic Sea seals. The estimated population of grey seals, and more endangered ringed seals living in Estonian waters, is 2 000 and 1 500 respectively. Both species are under protection.