From Ice Age to the present – Learning outdoors

The students of Honkajoki upper secondary school have hiked in Lauhanvuori National Park and foreign destinations and made observations about the environment. The students tell about their experiences and what they learned.

Erratics in Finland and Poland

Erratics are large rocks that have traveled at least twice their own length. The ice carried and moved the soil even long distances. As the ice melted, the material fell to the ground and the erratics were generated during the ice age. The erratics are used for landscaping and as decorative stones.

There are relatively many large erratics in Finland. The Finnish erratics have become detached from the bedrock of the surrounding area. For example, the erratic of Honkajoki may have become detached from nearby Lauhanvuori or even the Vaasa area.

The erratics have come to Poland from afar, even from Finland. There are not many of them in Poland. In Poland, the erratics are not as large as in Finland. In Poland, many erratics are also underground because there are thick layers of soil in the lowlands.

Photo: Kalle Männistö, Lauhanvuori National Park

Ancient shorelines on Lauhanvuori

During the last ice age, the continental glacier pressed the crust downwards. At the end of the ice age, the ground level began to return to the pre-ice age stage. After the ice melted about 10,500 years ago, Lauhanvuori was an island surrounded by the ancient phase of the Baltic Sea, Lake Ancylus. As the ground rose, Lauhanvuori merged with the mainland.

Ancient shore banks can be seen at the slopes of Lauhavuori. The banks have emerged as the water level has stayed the same for some time during land uplift. Shore formations have been formed and washed by waves at these elevations. In Lauhankangas, the old seashore stands out as a small rocky ridge.

Kivijata is a remnant of an ancient shore cliff. It has formed as a result of the crumbling of rock. The rocks have been affected by the ice age and subsequent coastal forces and earthquakes.

Photo: Kalle Männistö, Lauhanvuori National Park

Formations made by coastal sea currents in the Baltic Sea

The formation of spits

Spits emerge as wind and sea currents carry bottom sediment and form a new shore from it. In the Baltic Sea, the wind blows mainly from the southwest, and therefore thin and long spits emerge on the shores of the Baltic Sea.

The Vistula Spit

The Vistula Spit is located on the Polish coast in the Gulf of Gdańsk, east of Gdańsk. It is about 70 kilometers long and 1.8 kilometers wide at its widest. The Vistula Spit began to form about 8500-3000 years ago. There is sand on the Baltic side and rocks on the mainland side of the spit.

The Curonian Spit

The Curonian Spit is located in the southern part of Lithuania and is isolated from the mainland. The northern part of the Curonian Spit belongs to Russia. The spit is about 98 kilometers long and its width varies from about 400 meters to 3.8 kilometers. The cape runs from south to north.

There is a national park in the Curonian Spit and it was inscribed on the UNESCO World Heritage List and a World Heritage Site in 2000. It is a joint Lithuanian-Russian site, protected for its natural and cultural values as an example of an area where man has influenced the landscape. The northern part of the Curonian Spit, ie the Lithuanian side, is an exclave, which can only be reached by land via Russia.

The Hel Spit

The Hel Spit is a sandy cape in the Baltic Sea in Gdańsk Bay in northern Poland. The peninsula separates the Gulf of Puck from the Baltic Sea and is about 35 kilometers long. The Puck Bay is a shallow northwestern part of Gdańsk Bay. The width of the Hel Spit varies from 200 meters to three kilometers. The Hel Spit has been a very significant battle site during wars.

Photo: Juho Peltoniemi, The Hel Spit

While visiting Poland, we went to the Hel Spit by bus. It was a great experience. It was remarkable that the strip of land on which we drove was very narrow, but the journey to the end of the cape was still very long.

Also it was interesting to see how different nature was on the different sides of the road. On one side there were forest while on the other side there was harsher, drier and shorter vegetation. The mainland side was drier and there was only a small pebble beach. The seaside, on the other hand, had vegetation and a very large sandy beach.

The Heli Spit, like other spits, still grows all the time, so the sea-side strip of the spit gets wider. The beach spreads as new soil comes to the beach along the waves. The trees of the Hel Spit grow obliquely because of the strong wind on the beach and the soft terrain made up of fine sand.

Photo: Juho Peltoniemi, The Hel Spit

Kettle holes

Kettle holes were created during the ice age as ice melted. Large blocks of ice detached from the ice sheet and buried in the sand. As the ice melted, the kettle holes emerged in gravel or sand. Kettle holes are located on ridges and often have a round shape. Kettle holes have been utilized, for example, as shelters against enemies in ancient times.

Photo: Kalle Männistö, Lauhanvuori National Park

The kettle holes in Bialowietsa National Park are not very deep or large. The vegetation in the kettle holes is more lush than in the Finnish kettle holes, as they are located in the deciduous forest zone. The kettle holes are covered by organic material which is mainly decayed. The ice blocks in Poland have been small and therefore the Polish kettle holes are smaller compared to the Finnish kettle holes.

Photo: Risto Majakangas, Bialowietsa National Park

The Finnish forest reindeer and the wisent

The wicent

The wicent is very much similar to the American bison. It is the largest land mammal in Europe. The wisent herds graze in deciduous forests and forest meadows, eating grasses and tree leaves.

There lived wicents in many areas in Central and Eastern Europe in the 19th century. However, the species became rare due to hunting. In the first decades of the 20th century the last wild wicents of the Caucasus and Poland disappeared. The last wild wicent was shot in Bialowieza, Poland in 1921.

Fortunately, there still lived wisents in the zoos and some individuals could be moved to its natural habitats. The species was saved by the zoos as the first pedigree was established for the planned reproduction of this species. The 50 individuals reproduced so well that the species could be restored to the wild as early as the 1950s.

Wisents of Korkeasaari zoo have also been exported to a protected area in Russia. The current natural stock of the wisents is a couple of thousand individuals and conservation work continues. The species is still a part of the European protection program, which aims to increase the viable stock of zoos.

Photo: Kalle Männistö, Bialowietsa National Park

The Finnish forest reindeer

The Finnish forest reindeer is a wild relative of the reindeer that has adapted to the snowy coniferous forest. Its hooves are larger and its legs higher than those of a reindeer. An accurate sense of smell helps them to find lichen under the snow. The horns are narrower and therefore better in forests. The hooves of the deer also make a clicking sound, which allows the herd to hear each other and not get lost.

Finnish forest reindeers, a total of about 4,500 individuals, live only in Finland and Russian Karelia. The species once lived throughout the wooded area of Finland and was an important game animal as early as at the Stone Age. At the beginning of the 20th century, the species became extinct in Finland due to hunting, but afterwards some deer migrated to Kainuu from Russia. In Russia, deer are still extensively hunted. The species has been returned to Suomenselä and Ähtäri.

In 2016, the MetsäpeuraLIFE project, which aims to restore the Finnish forest reindeer into the Finnish nature, was started. Also Korkeasaari zoo participates the project. During the project, the species will be returned to nature in Southern Ostrobothnia and Pirkanmaa, in the vicinity of Lauhanvuori and Seitseminen National Parks. On the Russian side, the species is also being bred for wildlife restoration. You can also support the return of the species to southern Finland.

Photo: Juho Peltoniemi, Lauhanvuori National Park

Similarities of the wisent and the Finnish forest reindeer 

The wisent and the Finnish forest reindeer have a similar history. Both species have been hunted to extinction at the same time in the early 20th century. The Finnish forest reindeer live in coniferous forests only in Finland and Russian Karelia. The wisent lives in deciduous forests in Eastern and Central Europe.

Both species have been protected and their population has begun to rise. Wisents are protected, for example, in Bialowieza, Poland, which is the last large deciduous forest area still remaining in Europe. The Finnish forest reindeer is protected in Finland and thanks to the protection measures the population increases. In Lauhanvuori National Park, for example, a Finnish forest deer enclosure has been established. The aim is to generate a vibrant population in the Lauhanvuori area.

Some of the costs of the excursions have been covered by the EU-funded Lauhanvuori Region to Geopark project, which was implemented in 2016−2018.

Original text: The students of the Honkajoki upper secondary school

Main photo: Pasi Talvitie, Lauhanvuori National Park

The last photo: Juho Peltoniemi, Lauhanvuori National Park

Further reading:

Koivisto M. 2004: Jääkaudet.

Strahler A. ja Strahler A. 1951: Physical Geography.

One can learn about nature and the environment while hiking outdoors.