A Mosaic of Island Habitats

The biotopes of the archipelago vary a lot due to several factors – the limited access to top soil, the hilly terrain, varying exposure to wind and water, and different degrees of human influence. The islands are often a mosaic of different habitats, which produces an impressive level of biodiversity.


Different habitats

Primeval pine trees that are hundreds of years old grow on many islands. These are very important for several birds of prey, which use the sturdy trees for their extremely heavy nests. On wind-pined islands the trees are short, knotty and twisted. There are also deciduous forests, often marked by grazing, which has created open glades with a unique flora. Another habitat dependent on grazing animals is shore meadows with a lush vegetation of salt-resistant plants.

Small islets in the outer archipelago, where bird colonies nest, have a surprisingly diverse flora thanks to nitrogen-rich bird droppings. Cultural landscapes, often abandoned these days, were lands used for centuries by the island dwellers. Left behind are meadows, grown-over fields and wild remains from apple trees, hazel and roses.

Rocky pine forests

The most common habitat of the archipelago, these forests are found in the highest regions of the inner and middle archipelago islands. These pines appear knotty and short, and when exposed to strong winds also twisted. They are rooted in crevices where the roots can grow deep. There is a thin layer of top soil on the rocks where mosses, lichens, lingonberries and heather grow. In places with deeper well-drained soil, the pine trees can grow tall, thick and very old.

Pine and spruce forests

These pine forests, where the soil is deeper, feature lots of fallen trees, which is very valuable for many endangered lichens, mushrooms and insects. It’s unusual for pine trees to be left alone to die, fall and decompose naturally. The breakdown is very slow and species adapted to this way of life are either gone altogether or very rare.

Deciduous forests

These oak and linden dominated forests are found in the inner archipelago. Oak trees often grow in open environments marked by grazing. The thick trees are important for lichens, tree-growing mushrooms and insects. Linden grow in closed groves, often where open meadows used to be. The flora is rich with Ramps, Liverwort, Coral root, True lover’s knot, and the orchid Eggleaf Twayblade. Many linden trees show traces of a characteristic way of pruning, that allows for winter fodder for livestock.

Birch islets

On the border between the middle and outer parts of the archipelago, there is a long band of islets with short birch trees. The most characteristic “birch islets” are located in northern Saint Anna, where birch-clad bogs with bunchberries and crowberries are interchanged with barren rocky outcrops.

Cultural landscapes

Many islands in the archipelago have been influenced by human activity for a very long time. Only the barren little islets in the outer archipelago are completely unaffected. For centuries, fishing, hunting and raising livestock was how the island dwellers survived. . Growing crops on the islands became more prevalent in the 1800s, and many small fields were established in valleys or hallows. Most of these were abandoned decades ago, but there are still a few farmers on the islands. Sheep and cattle were shipped from islet to islet to graze, and this practice is still used today, although at a much smaller scale than in the past.

Grazing is very important for the biodiversity of the area, as it provides for a rich meadow flora instead of shrubs and grasses taking over. The Elder-flowered orchid is typical along with other flowers that thrive in sunny warm environments, e.g. Daisy, Bellflower, Knapweed, Rock-rose, Dropwort, Milkwort, Cow-wheat, Butterfly orchid and Bloody geranium.There are many remains from the island farmers, most notably stone fences and mounds, pruned linden trees and once domesticated plants and trees that now survive in the wild. It’s not unusual to find wild apple trees, roses and currants. Learn a lot more about the culture & history of the islands here.

Shore meadows

These meadows by sheltered and shallow creeks are dominated by salt-resistant plants and grasses. Most of the species that live here are dependant on continuous grazing or scything. Some typical plants are Sea sandwort, Seaside arrow grass, Seaside centaury, Sea plantain and Sea milk-wort. Many birds breed in this environment, for example Redshank, Peewit and Yellow wagtail. Sea meadows are also a popular resting spot for migratory birds.

Rocky beaches and outcrops

Many islands have rocky beaches that are very much effected by wind and waves. A lot of characteristic archipelago plants are found here, e.g. Sea aster, Woad and Longleaf speedwell. Nutrient-rich washed-up seaweed benefit Valerian, Silverweed and Angelica. Typical for this environment are rock pools, small collections of water among the rocks with no outlet. Here you may find Water-starwort and Gypsywort. Sandy beaches are very rare in these archipelagoes.

Furthest out to sea is the outer archipelago with its many small, barren islets that are heavily influenced by the sea. Many coastal birds breed out here, e.g. gulls & terns, and waders like Ruddy turnstone and Redshanks. Rarer species are Black guillemot, Razorbill and Arctic skua. There is a special habitat out here, lacking in soil but rich in nitrogen thanks copious amounts of bird droppings. Common plant species are Wild chives, Sedum, Orpine, Purple loosestrife, Wild pansy and White sticky catch-fly.