Fauna

The bats from the genus Plecotus have distinctively long ears, but when they are resting, they fold them under their wings. They feed mainly on nocturnal butterflies, flies, small turtles, but also caterpillars and spiders that they catch directly from twigs and leaves.

Their typical habitat is deciduous mixed forests. Long-eared bats mostly do not migrate; nevertheless, the furthest recorded migrations are those between summer and winter shelters, several tens of kilometres away. Summer maternity colonies are mostly formed in tree trunks or attics of churches and buildings, while caves, cellars and tunnels most often serve as winter shelters.

Ural owl (photo: D. Tome)

 

The Ural owl resides in mixed forests of mountain areas. Although owls of darker shades exist, this large owl’s feather adapts to the environment, becoming lighter due to the presence of snow. It was named the Ural owl because its tail is longer than the tail of other owl species. The fringed edges and huge surface of their wings allow for slow swinging, making the flight almost inaudible, and these owls a top predator that feeds on rodents and smaller birds. Bones, hair and other undigested remains are thrown out in the form of mucus.

The dormouse is a real sleepyhead! It spends more than six months in winter sleep, much longer than other mammals. When it finally wakes up in the spring, it first checks the buds such as beech or acorn, which will later produce fruits, for them the most delicious food. If there are not enough buds, they will return to their hiding place and continue to sleep until the next spring. The Romans hunted and prepared dormice in various ways, considering it a real delicacy.

Human fish (photo: M. Pršina, archive ZRSVN).

As early as in 1689, Janez Vajkard Valvasor wrote about the dragon offspring that he spotted in the bursting spring of Lintvern (near Vrhnika). He did not know what sort of animals these were and he described them as: “Probably a sort of lizard or an underground worm that can be found elsewhere as well.” Even then, he was aware that under the Earth’s surface there was something highly mysterious and hidden – the underground cave world. About a hundred years later, there was a battle for its description and prestige, in which Joseph Nicolai Laurenti won over Giovanni Antonio Scopolio. Thus, the human fish acquired its Latin name and became the first cave animal in the world to be scientifically described. Scopoli later correctly classified it among amphibians and not among fish, as the Slovenian name could mislead him. In 1801, it was presented to the scientists of that time in London and became world famous. Researchers were able to find the animals in the caves in the Dinaric Karst in Slovenia, Italy, Croatia, Bosnia and Herzegovina and Montenegro. The specimens were being sent from Slovenia all over the world; they were even experimentally inhabited in two European caves, where they supposedly live even today.

Cave beetle (photo: C. Mlinar, archive ZRSVN).

The story of the cave beetle Leptodirus hochenwartii is a bit younger but no less interesting. In 1831, a cave guide, Luka Čeč, discovered it in the Postojna Cave. He took it to Count Hochenwart, who showed it to Ferdinand Schmidt, an amateur entomologist who lived in Ljubljana and studied insects because he missed having his own garden. He described the beetle, gave it a Latin and a Slovenian name – “drobnovratnik”. This was the first described cave insect in the world. Since this animal was missing a part of the body, Schmidt offered the prize to the one who brought him a whole beetle. 16 long years after that, he found it himself. During his search, he discovered and described a wide array of other cave animals, showing the scientists an entirely new world below us. The Postojna Cave thus became the cradle of world speleobiology, that is, the biology of cave animals.

Fun Facts

BEARS’ HIBERNATION

Did you know that not all bears go into their dens in the winter? It all depends on the food supply in the autumn (when the bear accumulates fat) and in the winter (when there is markedly less food). If a bear is accustomed to food sources close to humans (composts, garbage cans, wild landfills, meat from the slaughter), it will not go into hibernation but will be visiting a village.

BEARS’ HIBERNATION

TREE ROOTS

Did you know that the roots of a tree extend beyond its treetop? In the forest, the roots of the trees touch and intertwine, protecting the forest ground from slipping and erosion.

TREE ROOTS

BARK BEETLES

Did you know that bark beetles are polygamists? The male hollows out a cubbyhole in the spruce tree and invites the females into it. Usually, 2 or 3 respond. After fertilisation, they each dig their own tunnel away from the cubbyhole and lay eggs in the walls of the tunnel.

BARK BEETLES

BLOSSOMS

Did you know that not all flowers have colourful blossoms? Along the Ajdovski zid wall, in the Kobilji curek stream and in Lanišče, we may observe a flowering henbane bell in April, which has black-purple, brown blossoms. The plant is poisonous.

BLOSSOMS

NEWTS AND FIRE-BELLIED TOADS

Did you know that newts and fire-bellied toads have warning colours only on their bellies? In case of danger, a fire-bellied toad throws itself on the back, arches its garish belly and plays dead. Predators think the animal is dead and bloated, thus inedible.

NEWTS AND FIRE-BELLIED TOADS

UNROOFED CAVE

Did you know that unroofed caves are created because their ceilings become thinner and then collapse? One day this will happen to the Postojna Cave and it will look like a cave by the Roman wall in Vrhnika.

UNROOFED CAVE