International Bat Night has been celebrated every year since 1997 around the end of August in some 30 countries, including Croatia. The message is clear: bats are not bloodthirsty vampires but indicators of a clean and healthy environment!
When Mirko Crnčević and his friends were small, they frequently used to watch the bats flying around our homes during the evenings. They would often spot their colonies in the belfries of little-used churches and in old, deserted houses... but sadly, although there are ever-increasing numbers of such houses in Croatia's rural areas, there are ever-decreasing numbers of bats. In recent times we rarely, almost never, come across them. Yet they are particular indicators of a clean and healthy environment.
Here we should note that there are well over a thousand species of bats and they constitute the second largest order of mammals on Earth after rodents. Altogether 34 species of bats are logged as living in Croatia, in three families: horseshoe bats (Rhinolophidae), European free-tailed bats (Molossidae) and evening bats (Vespertilionidae). As such they are present around mot of the world and fulfil vital ecological roles by pollinating flowers and disseminating fruit seeds. Bats are important for both health and the economy, because they eliminate insects which can carry various diseases, thus reducing the cost of healthcare as well as the need for using pesticides, particularly insecticides.
As in all other European countries, bats are strictly protected in Croatia in accordance with the Law on Nature Protection (law in Croatian). There are very high fines for causing bats harm, including by disturbing, capturing, wounding or killing them, or damaging and destroying their habitats. On August 31st 2023 multiple events were held from 10:30 am to 3:00 pm at the Imperial Viewpoint in the Krka National Park. The programme aimed to attract people of all ages with the aim of introducing them to the fascinating world of bats.
Instruction through play and entertainment
Visitors to the event were able to immerse themselves in the bats' wonderful world through a variety of educational games, workshops and activities, thus learning a great deal about bats, the only mammal which can fly. The contribution bats make to the ecosystem was highlighted in relevant decorative materials and inscriptions. Among other notable features was the key role bats play in regulating mosquito populations, as they devour these insects in great quantities and so are an important controlling mechanism for keeping mosquito numbers down.
As was explained during the Krka Bat Night programme: "Experts have calculated that a bat can consume many hundreds of mosquitoes in the space of an hour, thus contributing to keeping a balance in the natural environment. For our younger visitors we devised interactive games such as 'bat-fishing', 'bat-hunting' and 'blind polygon'. Naturally, these games were incentives which prompted them to look more closely at the world of bats besides helping them to understand bats' habits and behaviours. Older youngsters were able to experience the creative 'bat-corner', where they got to know these unusual creatures through drawing and various handicrafts."
Breaking down myths and prejudices
The International Bat Night event at the Krka National Park was the perfect opportunity to eliminate the prevalent myths and prejudices about bats. One of the most common misconceptions is that bats are totally blind, which is mistaken. Although their eyesight is limited, it is augmented by extraordinarily precise echolocation. Also, bats are not the bloodthirsty vampires portrayed in popular stories. There are only three species of bat which feed on blood, which live exclusively in Central and South America, while the vast majority eat insects, fruit and nectar.
The event was launched under the slogan "Let's give the bats more", by which the organisers at the Krka National Park emphasized how important bats are biologically and why their populations should be preserved. This is part of the National Park's mission to raise special awareness of the cave faunae which are exceptionally rich in the Dinaric karst. Many endemic species live in the caves in this area and bats are an important part of the underground ecosystem.
Bats in the Krka National Park
Interestingly, the Krka National Park is home to 17 species of bat, so half of the currently known species in the whole of Croatia. This diversity bears witness to the exceptional importance of the Park's ecology. The Miljacka II Cave is one of the most significant bat habitats in the whole of Europe, with a colony of some seven thousand long-legged bats.
As the organisers of the International Bat Night put it: "Our Park is not only a protected region, but also a centre for researching and preserving bats. During 2023, in collaboration with the Geonatura d.o.o. company, bats were observed during their seasonal migration. The research covered several speleological locations, including the Velika pećina Kaočinka and Topla pećina caves, which have been identified as important transitional sheltering spots for the bats."
Cave fauna - Dinaric treasure
The Dinaric karst caves which include those in the Krka National Park, are among the richest in the world for cave species. These creatures are adapted to living underground and have developed specific characteristics, such as a reduction in their visual organs and a loss of pigmentation. Around 170 cave species live in the Park, of which many are endemic to the Dinaric Alps, while four are steno-endemic in the Park.
The importance of these unique ecosystems is recognised at European Union level: many of Croatia's cave locations have been declared places of interest for preserving threatened species and habitats within the Natura 2000 ecological network. This network includes in its list 12 bat species recorded in the Krka National Park.
Protecting bats - a communal task
Despite their enormous importance, today bats are one of the most threatened groups of animals on Earth. There are many reasons for this: habitat loss, deforestation, intensive agriculture, increased tourism, among others. On a global level, 20 species of bats have died out in the last 50 years, and 25% of the remaining species are under threat. Their deaths are not only sad events, but are highly damaging to our increasingly beleaguered environment.