Shallow Archipelago with
Brackish Water
Natura 2000 area in Kvarken Archipelago covers, practically, the whole of the
outer archipelago zone in seven municipalities. The area is connected to the
protected areas in Sweden. The shortest distance between the Finnish and Swedish
islands is 20 km. Kvarken is also included in the list of areas protected by the
Baltic Marine Environment Protection Commission,
known as Helsinki Commission (www.helcom.fi).
Weighed Down by Ice
During the last Ice Age, the heavy ice sheet weighed down the earth's crust
as much as one kilometre. When the ice melted, the land uplift began, and it
will continue in Kvarken until the land reaches its original level, 100 - 150
metres above the current level. The rate of the land uplift in the area is 8 - 9
mm a year. Hundreds of thousands square metres of new land is exposed every
year. In about 2500 years, Kvarken will have become a neck of land, and the
northern part of the Gulf of Botnia will have become a lake,
with only a river connection to the Baltic Sea.
The edge of the melting ice created the washboard-like moraines, so called De
Geer moraines. They are exceptionally well formed and frequently appear in large
fields. Also, hummocky moraines and other types of transversal moraine ridges
occur. Because of its special geological features, Kvarken has been included on
the UNESCO World Heritage List as the first Nature Heritage
Site in Finland (www.kvarken.fi).
Constant Change
Because of the land uplift, the biotopes, flora and fauna are in a state of
constant change. Shallow bays become gradually separated from the sea, at first
being almost closed bays with frequent connection to the sea, and then becoming
lakes which only receive salt water when the sea level is high. In this kind of
lakes live mostly fresh-water species.
Forests which grow on land exposed from the sea are unique, because they are
only found in land uplift areas, and therefore Finland has a special
responsibility for protecting them.
Birds of the Archipelago
The shallow and rocky archipelago offers food and nesting places for
abundance of birds. Even the outer archipelago of Kvarken is one of the most
important nesting areas in the Baltic Sea for archipelago bird species. Most of
the Finnish population of the threatened Greater Scaup (Aythya marila),
for example, nest in Kvarken. The Black Guillemot (Cepphus grylle),
which is typical for the area, nests between the rocks. The White-tailed Eagle
(Haliaeetus albicilla) can often be seen wheeling over the forested
islands.
Low Salinity
The uniqueness of Kvarken is increased by the rapid decline in salinity of
the seawater when going towards the northern parts of the gulf, and by the
currents coming from south and north meeting at the narrow passage of Kvarken.
Water flows fast in Kvarken, and this affects the thickness of the ice cover in
the winter. If walking on the ice, you need to know where the currents are, to
avoid falling through the thin ice.
Traditional Agricultural Landscapes
Humans have been present in the area since the first islet of Kvarken emerged
from the sea. Pasturing and mowing have shaped the structure of the forests on
the islands. In the light forests growing on the wooded pastures lives even a
small population of the White-backed Woodpecker (Dendrocopos leucotos),
and several other woodpecker species. To keep the meadows and wooded pastures
open, pasturing is promoted in the area.
More information about the nature in the Kvarken Archipelago
Own website of the Kvarken Archipelago
(www.kvarken.fi)
