The year around - Northern Bornholm and Hammershus


Even before the winter is over, in the start of March, you may see pairs of peregrine falcons in the process of choosing suitable nest sites at the steep nesting cliffs. The razorbill return to their nesting colonies at Slotslyngen and Hammerknuden, the shadflower burgeons on the rocky heaths and migrating birds like the common crane, swans and loons passes Hammerodde on their way to their northern nesting grounds.

As the sun grows stronger the Black-and-Red-Bug wakes up from its winter hibernation. They use a couple of days in the sun to get warm before mating.

In late March the toads wander to the small ponds where they lay their eggs and in early April the European adder emerges from hibernation. The anemone and corydalis start growing in the forests and soon all the birds are nesting - except for the early nesters like the raven whose young have already hatched at this time.

The northwards migration of birds still continue since the insect eating birds have to wait until the weather in northern Scandinavia is warm enough for insects to hatch. In May the early-purple orchid and elder-flowered orchids bloom.


By June the eggs of the European herring gulls have hatched, and at Opalsøen you can get very close to the nests and see how the small spotted hatchling gulls explore the world before they have learned to fly.

In the ponds tadpoles have become little toads that are ready to spend the rest of the year on land. The roe hinds now have a kid or two and last years offspring have become young roe deer and now have to fend for themselves. In the dusk the bats hunt insects. During June the young peregrine falcons are ready to take to the air and you can see them practising their flight technique.

In June and July the carnivorous plant round-leaved sundew flowers in the wetlands and by July the young gulls are flying and the young razorbills now have a waterproof plumage and can leave the nesting cliffs.

When the swallow-wort blossoms you can see the Black-and-Red-bug suck up it's fluids. These are poisonous to other animals but are seemingly the only food source for the Black-and-Red-bug.

The summer and early fall is when the insects are plenty, and that means lots of food for bats, toads and the young birds who all need to grow fat before the winter. In August the European adder gives birth. The snake have adapted to the cold northern climate by its eggs in the stomach until they hatch.


By September the heather shows its purple flowers. The bedrock and the water are still warm from all the sun they have absorbed during the summer, so September on Bornholm is often warm. But the sun is getting weaker and while the fruit are ripening the first migrating birds start heading south.

By the Autumn Equinox day and night are equally long. The elderberries have ripened and soon the nuts will be ready too. There are still insects and mice, birds and other young animals are plentyfull and the animals are stocking up for the winter. The roe deer get fatter and change to their thicker winter fur. Snakes and toads are getting ready for the winter hibernation and cranes and other migrating birds travel to their winter habitats in the south and south west.

By October the leaves fall from the trees and it is the time of storms and the first frost.


The toads have dug into the ground to sleep through the winter, and so has the European Adder, often in old mice dens a meter or more below ground. Up to 100 snakes can spend the winter in such a hole. For the animals that spends winter above ground it is all about survival: Eating as much as possible while spending as little energy as possible.

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