Drop into Europe's biggest bat hibernation habitat

By Eva-Maria Mester Jul 12, 2011, 2:06 GMT

Bad Segeberg, Germany - Bats are fascinating creatures and one of the best places to observe their behaviour is in Germany's northernmost state of Schleswig-Holstein.

The bat capital of this federal state is the modest town of Bad Segeberg where more than 20,000 of the creatures spend the winter in and around the 'Kalkberg,' a so-called chalk mountain which is actually made of gypsum.

The Noctalis Experience Centre here is open the whole year round and offers a detailed insight into everyday bat life. During the summer months nature conservancy staff offer nighttime rambles which enable visitors to watch the bats as they flit about their business.

The climax of the summer season this year is on August 27 when the 15th European Bat Night takes place in Bad Segeberg in and around the Kalkberg caves.

A bat silhouetted against the night sky can easily be mistaken for a swallow. 'These are ones that often cruise around of an evening before sundown in search of insects,' said Ulrich Lensinger from the bat research unit of the Nabu nature preservation group in Schleswig-Holstein.

Ulrich is on hand to observe the bats with visitors young and old alike and he can even tune in on the sounds. At these 'eavesdropping sessions' he uses as a bat detector to capture the bat's high-pitched, ultrasonic echo-location sounds and convert them into signals audible to humans.

A typical trip lasts about 90 minutes and usually starts at dusk. Such guided tours are not only offered in Bad Segeberg. Similar bat trails exist on the Baltic coast at Dahme and Scharbeutz, in the Eekholt Country park or near the village of Toenning on the Fresian coast.

Despite the many different bat species to be found here, all of them feel comfortable spending the winter in the gypsum caves at Bad Segeberg. The area is therefore off-limits to the general public from October to March.

The displays at Noctalis give an idea of how the creatures spend the cold months. Visitors each pick up a torch at the entrance, enabling them to spot the creatures clinging to the walls in hibernation, their compact bodies covered in dew drops.

This is Europe's largest natural hibernation habitat which is crowded in winter but sleeps only a few hundred animals in the summer months. Most of the bats take their leave at the end of March and return in late summer.

In a so-called vivarium, a closed space designed to simulate the bat environment, short-tailed bats whirr behind glass. 'Unlike our indigenous species which feed on insects these short-tailed bats from South America live on fruit,' explains our guide. The South American continent is also home to three bat varieties which feed on the blood of other animals but these are unknown in northern latitudes.