10 Suolijärvi nature trail information board
Have you seen a bat?
Against the pale summer night sky, you might see the black-hued mammals – bats – swiftly fly by. Bats are very efficient predators – one bat can eat thousands of mosquitoes and other insects in one night! This predatory power makes bats an important regulator of insect populations. Various species of winged bats can be met at Suolijärvi.
The ultrasound of a bug zapper in the night
A bat senses its surroundings by using sonar waves. It emits high-pitched sounds; when these sounds hit objects in the environment, they bounce back to the bat's ears. This allows the bat to judge the distances and directions of targets in the dark of the night. Trekkers can sleep without any disturbance, as the bat's echolocation sound frequency is well above the human hearing range.
The annual cycle of leather wings
Around midsummer, bats give birth to a single chick and establish a breeding colony of females and chicks.
Between September and October, the bats retire to hibernation roosts, i.e. caves, caverns and building shelters. Some bats leave Finland for central Europe to hibernate.
Protection of bats
Bats are strictly protected in Finland, which means that their habitats and roosts must be protected and preserved. The lack of old-growth forests also affects bats, as it does the flying squirrel. You can support bat roosting by hanging bat boxes in sunny places, as they thrive in warm daytime roosts.
Bat species common in Finland:
- Northern bat
- Water hyena
- Whiskered Finch
- Great Crested Finch
- Earwig
