Looking at the metropolis of Cluj-Napoca, we would be tempted to think that there is not much diversity of animals on its streets. However, they are present in both large numbers and species. Among these are the bats of Cluj, nocturnal animals that use echolocation to orient themselves in the dark and that consume “industrial” quantities of insects.

Of course, bats are harmless to us humans, but the same cannot be said about insects: they are the only source of food for Romanian bats. Bats are often present around us without us realizing it, either in the attics of buildings, in basements or even in wall cracks. They can be present even in the hollow trees, that we walk past every day in the parks of Cluj. We can often observe them in the evening chasing insects by light poles, appearing only for a second, and then disappearing again into the darkness. We just have to stay for a while on the bank of the Someș, or at the lake in the central park, and we will observe the bats that feed on insects. And when it comes to feeding, bats are real machines specialized in capturing insects in all kinds of environments, whether next to light poles, or above water, or even between and from the leaves of trees in parks.

But still, how many insects does a bat eat in one night? Estimates show that a single specimen can consume hundreds of insects per night (ex. mosquitoes), and some species can consume their own weight in insects per night. With these examples in mind, we can imagine what a summer without bats would be lik. And how uncomfortable it would be if bats didn’t keep the insect populations around us under some control.

Considering that it is an area heavily modified by us, humans, Cluj-Napoca still has a high diversity when it comes to bats. During the years 2018-2021, in a study that included several areas within the city, but also adjacent areas such as the Făgetul Clujului Forest, the CBRC identified 14 bat species (out of the 32 in Romania). Urban areas include common species, for example the noctule, or the pipistrelle, and the more natural areas include strictly protected species, for example the barbastelle in Făgetul Clujului Forest. At the water surfaces in the central park, at the Someș or in the East Park, but even in the Botanical Garden, the Daubentonás bat hunts continuously. Here we also find long-eared bats, for example the gray long-eared bat, which prefers to hunt inside the canopy of trees.

This shows us that the metropolitan area of Cluj-Napoca, although it is constantly developing, still has a lot of favorable environments for bats. Obviously, Făgetul Clujului Forest is the most diverse (with 12 species identified), followed by the Botanical Garden with at least nine species present. The East Park area can also be considered a diverse one, with at least eight species of bats consuming insects wholesale, especially above the lakes. The Someș River and its tree banks are also areas where bats do this intense insect-feeding activity during the night. And the Central Park, in addition to the presence of insects, also offers shelters for bats, through the existence of old, hollow trees.

Bats of Cluj, including of Făgetul Clujului Forest, according to Bücs & Stan (2018), Bodea (2021) and CBRC (2022):

  • Lesser mouse-eared (Myotis blythii)
  • Geoffroy’s bat (Myotis emarginatus)
  • Natterer’s bat (Myotis nattereri)
  • Daubenton’s bat (Myotis daubentonii)
  • Noctule (Nyctalus noctula)
  • Serotine (Eptesicus serotinus)
  • Parti-colored bat (Vespertilio murinus)
  • Pipistrelle (Pipistrellus pipistrellus)
  • Soprano pipistrelle (Pipistrellus pygmaeus)
  • Kuhl’s pipistrelle (Pipistrellus kuhlii)
  • Savii’s pipistrelle (Hypsugo savii)
  • Brown long-eared bat (Plecotus auritus)
  • Gray long-eared bat (Plecotus austriacus)
  • Barbastelle (Barbastella barbastellus)

From the point of view of bats, Făgetul Clujului Forest is the most important area in Cluj-Napoca. Here we also know of the existence of a Barbastelle colony, a typical bat species for old-growth forests with high natural value. The colony uses one of the artificial houses placed 3 years ago in the forest, they hunting insects all over the area. In order to emphasize the natural value of Făgetul Clujului Forest, the CBRC, in partnership with Natura Transilvaniei, through a sponsorship from Betfair Romania, created the “Squirrel Trail” thematic route, which includes both informative boards about bats, and artificial bat boxes, that can be checked by anyone for the presence of bats.

The bats of Cluj are ok, but this can still be improved. Bats are still negatively affected by our activities, whether it is cutting down old trees, renovating the attics of buildings, where colonies are located, excessively light-polluting buildings, polluting water, or even believing in factually untrue bat myths. Bats do not get into our hair, and they have no business with our blood. Bats do not seek the company of humans. It is important to understand that we must be tolerant of bats, and not afraid of them: bats want to deal only with insects. The truth is that with every encounter, bats are more scared of us than the other way around.

As with any other group of animals, it is our human duty to protect them and take steps to make their lives easier. Just as they also bring us free benefits through their existence. Only by protecting the bat populations in the Cluj-Napoca area will we continue to benefit from all the advantages they offer us!


  • Bodea F. (2021): Chiropterofauna of the Cluj-Napoca metropolitan area. Dissertation work, Faculty of Biology and Geology, “Babeș-Bolyai” University Cluj-Napoca.
  • Bücs Sz.L., Stan OM (2018): Preliminary data on the chiropterofauna of East Park, Cluj-Napoca. The National Conference of Chiropterology from Romania, edition III, October 2018, Cernatu de Sus, Covasna county.
  • Center for Research and Conservation of Bats (2022): Chiropterofauna of East Park, Cluj-Napoca and the impact of park development on bats. Report within the project “Biodiversity study necessary for the realization of the design documentation for the development of the East Park in Cluj-Napoca”

Die Fledermäuse von Cluj

Betrachtet man die Metropole Cluj-Napoca, drängt sich der Gedanke auf, dass es auf ihren Straßen keine große Tiervielfalt gibt. Zumindest für Fledermäuse ist dies jedoch nicht der Fall. Fledermäuse sind für uns Menschen ungefährlich, das gilt jedoch nicht für Insekten: Sie sind die einzige Nahrungsquelle für rumänische Fledermäuse. Fledermäuse sind oft unbemerkt um uns herum, sei es auf Dachböden von Gebäuden, in Kellern oder sogar in Mauerritzen. Sie können sogar in den hohlen Bäumen präsent sein, an denen wir jeden Tag in den Parks von Cluj vorbeigehen. Wenn man bedenkt, dass es sich um ein von uns Menschen stark verändertes Gebiet handelt, weist Cluj-Napoca immer noch eine große Vielfalt an Fledermäusen auf. In den Jahren 2018-2021 identifizierte eine Studie hier 14 Fledermausarten (von den 32 in Rumänien). Der Wald Făgetul Clujului ist der vielfältigste (mit 12 identifizierten Arten), gefolgt vom Botanischen Garten mit mindestens neun Arten. Der Östliche Park kann auch als vielfältig angesehen werden, mit mindestens acht Fledermausarten, die Insekten im großen Stil fressen, insbesondere über den Seen.

Vorhandene Fledermausarten: Myotis blythii, Myotis emarginatus, Myotis nattereri, Myotis daubentonii, Nyctalus noctula, Eptesicus serotinus, Vespertilio murinus, Pipistrellus pipistrellus, Pipistrellus pygmaeus, Pipistrellus kuhlii, Hypsugo savii, Plecotus auritus, Plecotus austriacus, Barbastella barbastellus.

Die Fledermaussituation in Cluj ist in Ordnung, aber auch verbesserungswürdig. Fledermäuse werden immer noch von unseren Aktivitäten negativ beeinflusst, sei es das Fällen alter Bäume, das Renovieren von Dachböden von Gebäuden, wo sich Kolonien befinden, übermäßig lichtverschmutzende Gebäude, verschmutztes Wasser oder sogar der Glaube an sachlich unwahre Fledermausmythen. Fledermäuse kommen nicht in unsere Haare und sie haben nichts mit unserem Blut zu tun. Fledermäuse suchen nicht die Gesellschaft von Menschen. Es ist wichtig zu verstehen, dass wir gegenüber Fledermäusen tolerant sein müssen und keine Angst vor ihnen haben müssen: Fledermäuse wollen nur mit Insekten fertig werden. Die Wahrheit ist, dass Fledermäuse bei jeder Begegnung mehr Angst vor uns haben als umgekehrt. Wie bei jeder anderen Tiergruppe ist es unsere menschliche Pflicht, sie zu schützen und Maßnahmen zu ergreifen, um ihr Leben einfacher zu machen. So wie sie uns durch ihre Existenz auch kostenlose Vorteile bringen. Nur durch den Schutz der Fledermauspopulationen im Cluj-Napoca werden wir weiterhin alle Vorteile nutzen können, die sie uns bieten!