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30,000 years ago glaciers covered vast areas of the Northern Hemisphere. As so much water was trapped on land, in the form of glacial ice, the sea lay 120 metres below its present level. This meant that the North Sea was dry land, a treeless tundra, with long, winding rivers,endless stretches of boggy land and wide, sandy heaths. Only as far south as the Mediterranean and the Black Sea were there any forests.
As the climate slowly improved and the Scandinavian peninsula rose from the grip of the ice, plants and animals started to invade the new territory. As soon as there was dry land the first plants took root and with them came animals, birds and insects. The first of these were the Arctic animals such as wild reindeer, arctic fox, wolf and wolverine (glutton), who followed the edge of the glacier up to the mountains. The trees came later, accompanied by a rich flora and fauna including bears, lynx,elk, marten, fox, hare, beaver and otter. This influx reached its climax around 3000 BC when the climate improved considerably, giving rise to the postglacial period of warmth. The average temperature rose 3 degrees. This may not sound very much, but in the mountains the tree line rises about 100 metres up the mountainside for each degree M so the consequences were dramatic. Most of the mountains of Norway M which today occupy about three quarters of the land mass M became covered with dense forests of pine and birch. The glaciers had thawed and vanished, and extensive oak forests, not unlike those we see today in Central Europe, spread over the low-lying land. Life was hard for the animals and plants in the high mountains, as they were pressed up towards the highest peaks, which rose like islands from a sea of forest.
The warm period, which coincided with the Bronze Age, lasted about 2,500 years. But around 500 BC the climate again started to cool and within the course of a few hundred years a new climate was established, very like the one that Norway has to this day. The forests receded and the plants and animals that had been forced to move up into the high mountains moved down to their former territories. Animals like the wild boar fled the country, never to return. At this time the spruce appeared. During the Ice Age it had been pushed towards the Urals, and in the last 15,000 years it has spread steadily westwards. About the time of Christ's birth the whole of Sweden and Finland were covered by spruce, and it also encroached along a broad front in Norway. Today it has conquered the whole of southeast and mid Norway where the extensive forests of pine and deciduous trees have given way to the dark and gloomy spruce. The invasion continues westwards and in about 1,000 years the whole of western and northern Norway may have been "conquered".
Norway's fauna and flora have been strongly influenced by the new incursions, but also by the fact that the climate is the prime factor in determining distribution patterns. Norway has perhaps one of Europe's most variable climates, due to its proximity to the Atlantic and to its 2,500 km long coast, along a north-south axis.
Along the west coast the winter is mild and snowfalls rare. Here are a number of the plants which cannot tolerate frost, for example the star hyacinth (scilla verna) and the purple heather (erica purpurea), which are otherwise only found in England, Ireland and further south.
A little further inland we come upon the species which can withstand short periods of frost and snow in winter. These are found both a little further north, and in the fjords. Typical examples are the foxglove (digitalis purpurea) and the holly (ilex aquifolium), which in Norway grow only in the southwest. In the southeastern part of the country, around Oslo, the climate is continental, with a long, cold winter and a dry, warm summer, providing the basis for quite different species to those of the west. These include the blue anemone (anemone hepatica) and the aconite (aconitum septentrionale). These can withstand a long winter "hibernation" beneath a covering of snow, while they need good summer warmth to ripen the seeds.
The trees have other requirements. The pine is a robust tree which quickly spread throughout the country, as far north as Porsanger only 50 km south of the North Cape. Both the pine and the other Norwegian conifers, like the spruce, juniper and yew retain their leaves M or needles M throughout the year, so with the advent of spring they are ready to start immediate growth. In the winter their needles curl up in order to retain moisture. Winter dries out the plants, the frozen ground making it impossible for them to obtain moisture, for periods of as much as 6-7 months.
Deciduous trees solve this problem by shedding their leaves in the autumn, before the dry period begins. As their bark is virtually impermeable they do not dry out, and therefore survive the winter without much difficulty. In Norway, as in the rest of Europe, it is the seed ripening that determines the limits of their distribution. The warmth-loving deciduous trees such as oak, ash, lime, hazel, elm and maple grow only in a wide belt along the south coast and up to Trondheim in mid Norway. Further north and up towards the mountains it is the robust and undemanding trees that replace them; such as the birch, the mountain ash and the aspen. These manage to ripen their seeds despite a short, cool summer and they can consequently be found almost as far up as the North Cape.
Plant species spread from Siberia too. From this region came the special plants that followed the sea coasts and the major rivers. In the post Ice Age period several of the large Norwegian rivers in Finnmark were also fed by water coming from Russia, so there were many incursory routes. But these immigrants from the northeast soon came up against the forests, which spread from the south and their advance was halted. Consequently, the Siberian species are generally only found in Finnmark and Troms, Norway's two most northerly counties. A good example of this group is the siberian garlic (allium sibiricum). This grows in all the fjords of Finnmark, often in such quantities that the milk becomes onion flavoured if the cows each too much of it. Other species are the fringed pink (dianthus superbus) and the sneezewort (veratrum album). The latter is a large lily plant which also grows in the mountains of Central Europe. There is a wide variety of mountain plants in Norway on account of the variable climate, but also because of a highly diverse geology, shifting from limestone to acidic granites. This provides a basis for a wide range of species. Many of Norway's mountain plants can also be found in the Alps, having come from the south as the land mass of Norway gradually rose from the ice. But there are several other groups which appear to have mysterious origins and which have long puzzled Norwegian botanists. In the Gudbrandsdal valley, north of Oslo,are a number of species which can otherwise only be found in eastern Finland or the Carpathian mountains of Czechoslovakia. A good example of these is the alpine clematis (clematis alpina). This grows M completely isolated M in the mountain clefts of Gudbrandsdalen, thousands of miles from others of its kind. We do not know how and when this species came to Norway.
Another, bigger group is about 30 American mountain species. In Europe these grow only in two mountainous parts of Norway, in the Dovre and Jotunheim mountains of southern Norway and in the Saltdal to Finnmark region of the north. In America these species grow only in Canada and Greenland. When they came to Norway, and why they did not spread to other mountainous regions of Europe are unanswered questions. Despite a host of theories, no one knows the answer. Did they survive the winters on the tundra to the south and east of the ice sheets and move in later? How did they cross the Atlantic? Were they brought by birds when the ice started to thaw, or did they blow over? One species every 800 years would be sufficient to explain their pattern of distribution. At Kautokeino in Finnmark we find another mysterious species, the masi oxytrope (oxytropis deflexa). To find others of its kin one must travel 800 km further east, to the Altai mountains of Asia. No one knows how and when this strange guest came to Kautokeino, and why it is only found there. Many such riddles exist in the world of Norwegian mountain plants and many more will doubtless be revealed when the whole country has been properly botanically charted.
With the advent of plants come animals, and the post Ice Age in Norway was no exception. In the mountains and on the treeless tundra wolves and wolverines hunted huge flocks of reindeer. Other species which arrived at the same time were arctic fox, hare, stoat and several small rodents. The best known of these is the lemming. The numbers of small rodents vary over a four-year cycle. In the first three to four years there is a steady increase, which is followed, in the course of a few months, by a dramatic fall. The cause of these fluctuations is not known, though theories abound. In addition to this four year variation the lemmings go through a violent population explosion every 11 to 12 years. Competition for food is so fierce that many animals start to move over wide areas. In a so-called lemming year the mountains and contiguous areas teem with countless thousands of these small animals. In such years predators and birds of prey have a rich source of food and often give birth to twice as many young as they usually do. Hunters look forward to lemming years as they invariably bring very large numbers of grouse to the mountains. The reason for this abundance is that the birds of prey, which would otherwise have eaten partridge eggs and chicks, feed exclusively on the lemmings, which are far easier to catch. The lemming has fascinated man since prehistoric times, and in the Middle Ages it was believed that they fell from the heavens during thunderstorms. Naturalists could find no convincing reason for the enormous increase in their numbers.
An alien guest in the Norwegian mountains during lemming years is the snowy owl, three feet in length and dazzling white. It inhabits the polar regions, but often flies thousands of kilometres if there are good supplies of small rodents. How it knows beforehand of the occurrence of lemming years is another of nature's mysteries.
Bird life in the mountains clearly reflects the difficulty of living in such hostile regions in the winter. Apart from ravens and grouse,all the mountain birds are migratory. Some move only down to the coast, while others make their way to the Mediterranean and Africa. The raven eats carrion after the wolf and wolverine and whatever it can find of dead animals and refuse. The partridge lives on the buds of creeping willow and birch. When storms come up, which they frequently do, it digs itself down into the snow and literally sleeps it off. The snow provides excellent insulation because of the air which is trapped between the flakes. A little beneath the snow surface the temperature never falls below minus five celsius.
When the forests spread to Norway a rich fauna of forest animals accompanied it, such as bears, lynx, martens, elk, deer, squirrel and beaver. The woods were also filled with birds such as the large gallinaceous species, the capercaillie (or wood grouse) and the black grouse, in addition to numerous owls, woodpeckers, birds of prey and large numbers of small birds. To the lakes and marshy land came species such as the crane, the whooper swan, grebes, geese, ducks and many waders. Along the coast were the nesting cliffs, with their teeming millions of kittiwakes, guillemots, auks, puffins, cormorants and gulls. In this natural pantry the sea eagle makes his home. Sick or enfeebled birds are ruthlessly singled out by this king of the coastal waters. About 30-40 years ago the sea eagle was an endangered species, but today its numbers are growing and it is even being exported to other countries where it had been extinct, in the hope of establishing new and vigorous stocks.
The great auk was 50 cm long and resembled a penguin. It nested in its millions around the entire Atlantic , and was an important item on the menu of the men of the Stone and Bronze Ages. But it could not fly and this was its undoing. The great auk was hunted relentlessly. By about 1750 it had disappeared from Norway and a hundred years later the last specimen was shot near Iceland M yet another example of man's mindless rape of nature.
Along the coast there were also large numbers of seals and whales. The ancestors of the present Norwegians hunted many seal, but provided that reserves of fish were not overfished there was room for both. Indiscriminate hunting has left only small reserves, but total protection has led to an increase in their numbers.
The fish are a very different matter. The first to arrive were arctic species such as cod,haddock, coalfish and halibut. These spread along the whole coast up to the Arctic Sea and since time immemorial they have been a main means of subsistence to the coastal population. Many species live far out at sea, only coming to the coast to spawn. The most important of these is the cod which lives in the Barents Sea and migrates to the Lofoten Islands where it spawns in huge numbers. As far back as the Viking age the cod was extensively fished and right through the Middle Ages dried cod from Lofoten constituted between 40 and 70 per cent of Norway's export.
As the rivers emerged from the ice, salmon, trout and char swam up to spawn. These are the only fish along Norway's coast that can live in both salt and fresh water. The trout and char remained in the lakes, and were often removed further up river by man. But the salmon grows to maturity in the sea and only swims up river to spawn and later to die. In the following spring the young salmon return to the sea on the spring flood.
In a period following the Ice Age the land lay higher than it does today around Denmark and the south of Sweden. The Baltic was then filled with fresh water coming down from the rivers and the water ran out into the White Sea by way of the great Russian lakes, Ladoga and Onega, north of Leningrad. The freshwater Baltic became full of fish from the Central European rivers and from there, there was an open way to Scandinavia. The most important of the species that came this way include perch, powan,pike and grayling. They are often called whitefish on account of the fact that they live on plant remains, insects and animals, and not on crustaceans which tint their meat pink, like the salmon, trout and char. They swam, by way of the Swedish and Finnish rivers, to eastern Norway and to Finnmark. They are aggressive fish and in the lower lying country they pushed out the trout and char. The mountains barred the way to west and mid Norway, so in those rivers there are only trout and salmon.
What then is the status quo for animal life in Norway today? The large predators such as lynx,wolverine, bear and wolf are virtually extinct. In their place are 2 million sheep and about 200,000 domesticated reindeer. The wolf has almost disappeared, but there are small populations of the other animals. The last of Europe's wild reindeer are now found only on the Hardangervidda and its adjacent mountain areas. There are about 15,000 of these animals M a healthy stock. Big changes have also taken place in the forests. Widescale felling of trees, leaving denuded areas, has completely altered the environment. Reserves of bears and martens have rapidly declined, along with capercaillie and black grouse. The elk, on the other hand, benefits from the grazing possibilities on the treeless areas and its numbers have multiplied during the past 40 to 50 years. About 40,000 to 50,000 animals are culled every year, with no apparent detriment to their numbers.
The beaver is a classic example of successful protection. Immediately prior to the World War the entire European stock of beavers was around 500-600 animals, largely found in the Agder counties of southern Norway. Total protection has led to a strong increase in numbers and the beavers have also moved out to occupy extensive tracts of their old hunting grounds on the Scandinavian peninsula. Norway has even sent a number of beavers to Switzerland, Czechoslovakia and the USSR, to enable these countries to regain at least some of their original fauna.