As we already detailed in the section about the necessity of protecting bats, they would rather live in a natural environment, outside cities and villages. They prefer Nature: caves, forests, meadows, and grass lands. But the urban environment, localities, cities, villages, can also attract bats. We can come across bats in attics, lofts, cellars, basements, between elements of a construction, or other locations. In the following lines you can find out more about:

As we said, we can encounter bats in the urban environment, in villages and cities. While encounters in nature can leave us with memorable memories, encounters in basements, in buildings or, worst-case scenario, inside our own homes, usually provokes loathing or fear. Most of the times, we, humans, think that bats should not be around us. This kind of thinking stops when we find out about the benefits we obtain due to the presence of bats.

Bat presence in cities is not an elaborate invasion plan, but actually it is because humans continue to modify the natural landscape. Forested areas disappear in a matter of days, rivers are blocked by power plants or dams, and caves become touristic attractions visited intensely and usually irresponsible. With other words, bats are forced to leave their homes and search for alternative refuges and feeding grounds. And they don’t search for long: if they find a place where they can rest and eat, they accept it.

Based on these criteria, the urban environment is a good place. Attics and church towers have the right temperature for maternity colonies over the summer, while basements and tunnels are perfect for hibernation in winter. Parks and other green spaces in the urban environments, forests and fields close to cities, but also the light from public illumination systems attracts high quantities of insects, the food of choice of bats.

What should we do if we encounter bats in the urban environment?

The most common species of bats from the urban environment are the Noctule, common Pipistrelle, Daubenton’s Bat, and even more sensitive species such as Geoffroy’s Bat, the greater horseshoe bat or the lesser horseshoe bat. The highest chances for you to come face-to-face with a bat in the urban areas are in summer and autumn, when bats are at their highest activity: maternity, respectively mating. Even for such unexpected encounters, if we follow a simple set of rules, we can diminish the stress we provoke on bats, and also diminish our own negative experiences.

The most important thing is to avoid panicking: bats won’t get caught in our hair, they won’t attack us in our sleep, they won’t eat from our kitchen, and they won’t make a nest. These are only urban myths and are easily debunked. We also shouldn’t be scared because bats are most certainly more scared of us, than we are of them. They are in an unknown location, alone, without their colony and without any recognizable elements that can help them find their way to freedom.

It is important to not hit bats as we would do with mosquitoes, otherwise we could break their wings. The best option is to leave the window or door open, and the bat can get out on its own. If the bat doesn’t want to get out, we can wait for him to settle down somewhere and then, with a towel, we can grab him (the towel is necessary to avoid being bitten, as bats have pretty nasty teeth). With the bat in the towel, we can release it through the window and it will most certainly fly away. If this doesn’t work, we can keep it in a box (with small breathing holes!). The box should have inside some textile material so the bat can hide in it, if he feels the need to. Bats are true masters of escape through the tiniest spaces, so we have to be sure that the box is sealed properly. On a short-need basis, water is more important for bats than food (as is for humans). If we keep the bat in a box we should leave it with a small lid full of water.

When night comes, if the bat is agitated and it is not injured, we can release it in a park or forest nearby. If we free it without the help or supervision of a trained person, we should be sure that no hungry cat is nearby and if the bat doesn’t take flight immediately, we should put it as high up as possible on a tree trunk.

There are small chances for us to encounter bats in our house during winter. But this can happen from time to time. Bats would rather hibernate in caves, abandoned mines or other underground roosts. Still, there are some small species which prefer cracks and cellars in buildings.  In case we encounter a bat during the cold season (active or inactive) we suggest to put it in a box, as detailed previously.

Generally speaking, if the bat seems to be injured, we have to call a specialist. In complicated cases, such as coming across a colony in our area, there are some solutions to be applied that would avoid both bat and human “casualties”. In these cases, we should first take into account if the bat colony is a disturbance indeed, does it have any kind of negative impact, or if it is just our fears and negative emotions? If the former is true and we have to move the colony, the action should be wisely thought beforehand. The most optimal way of dealing with this kind of situations is to contact specialists and listen to their advice.

By putting in action the measures described in the previous lines and by keeping calm, the chances of a bat biting us are slim. Anyway, if we get bitten, we don’t have to panic. Bats are wild animals and they bite to protect themselves, by instinct, not necessarily because they have rabies. Even so, bats can be carriers of rabies, although the incidence is low. A recent study has shown that 11 bats out of 12.000 individuals carry rabies, meaning 0.0009%. Still, if you get bitten by a bat, it is more cautious to check with your doctor and see if there is need to take the rabies vaccine.

In our behavior towards bats, we have to take into account the fact that European bat species, which include all bat species from Romania, are protected by law. For example, Annex II of Habitat Directive of the European Union, respectively Annex III of Ordonnance 57/2007 of the Romanian law, states that a number of bat species are strictly protected. We are not allowed to move these species if they create a disturbance. In case we come across such situations, we have to find the best solution to protect the bat colony and the buildings and human residents.

The effects of human presence on bats

Human activities can have negative impacts on both bat individuals and colonies from caves or other roosts. Generally speaking, any kind of human activity can impact bat colonies simply by intrusion or modification of their habitat.

The impact of human presence on bats is well documented throughout scientific articles. Speakman et al. (1991) evaluated different stimuli (tactile and non-tactile), associated with human presence, on hibernating colonies and energetic costs. Bats consume 0.001 g of fat for each non-tactile stimuli and 0.05 g of fat for each tactile stimuli. Seeing that some bats species have a small weight (ex.: Myotis myotis 25-30 g, Rhinolophus hipposideros 5-7 g) and fat reserves are only 30% of their body weight, we can easily say that any stimuli can significantly impact fat reserves consumptions. The survival of an individual during winter and coming out of hibernation successfully can be impacted negatively. Johnson et al. (1998) has studied and measured over 4.000 individuals of Myotis sodalis in caves from Indiana, USA. Comparing their weights before and after hibernation both in individuals in caves he visited (378 visits during winter) and has not visited (5 visits during winter). The least amount of fat consumed by bats was in the cave he didn’t visit at all during winter, only 15% of fat reserves have been consumed. In the cave most often visited, bats lost about 33% of fat reserves.

Thomas (1995), with the help of infrared cameras, has shown that in a hibernation shelter from USA with almost 1.300 individuals from Myotis lucifugus and Myotis septentrionalis, bats are more active during tourists presence, and especially immediately after their leaving. Bat activity started to go up after less than 30 minutes after each visit, reaching a maximum at 1-7 hours and staying abnormally high even 8 hours after a tourist visit. Thomas (1995) demonstrated that bats can come awake and become very active even in absence of tactile stimuli, just because of human presence. In order to avoid the unnecessary consumption of fat reserves by bats, the author recommends to keep the number of tourist visits at a minimum in hibernation shelters.

Mann et al. (2002) has studied the effects of cave tourism on maternity colonies of Myotis velifer in Arizona, USA. He demonstrated the fact that bats become more active when the tourism route goes nearby the colony, and illuminations is having the biggest effect. The number of tourists in a group doesn’t affect bats. Kofoky et al. (2006), in a study in Madagascar, has demonstrated that caves that are frequently visited, have the smallest bat populations and the smallest species diversity. The least visited cave was home to 54% of the winter fauna and 99% of the summer fauna of bats, and was being named a site of national importance.

Olson et al. (2011), in a cave in Canada, has observed a significant growth in the numbers of hibernating individuals (actually a doubling number) after restricting winter visits in the cave. This growth had taken place not because the cave was closed, but because there was an active campaign of informing people about the presence of bats and the periods when visits shouldn’t take place. Paksuz and Ozkan (2012) observed in three caves in Turkey the growth of the colony with thousands of individuals after restricting visits. The restriction took place by installing a gate and after changing the tourist route. But Furman et al. (2012) suggests that the growth of bat populations observed by Paksuz and Ozkan (2012) is actually caused by the fact that the local population has moved in the part of the cave inaccessible to tourists.

Cardiff et al. (2012) has evaluated the effects of direct and indirect illumination on R. madagaskarensis colonies from Ankarana National Park. In the colonies that were not used to tourist visits and artificial light, even an indirect illumination from 12-14 m has caused a disturbance and a growth in the activity of the colony. The authors recommend that such caves shouldn’t become opened to tourism.

In Romania, Petrea et al. (2005) observed a growth of over 300% (from 83 to 406 individuals) in a hibernating colony from Cave Cicolovina Uscată, after closing the artificial entry and putting up a bat-friendly grate at the natural opening of the cave.  Gheorghiu et al. (2009) and Chachula et al. (2012) continued observing the growth of this population. Borda et al. (2010) noted the return of the maternity colony of M. scheibersii in Poarta lui Ionele Cave, after blocking the entrance to the superior part of the cave. Szodoray-Paradi et al. (2013) observed the growth of R. ferrumequinum colonies in numerous caves from Pădurea Craiului Mountains and from Bihor, after installing conservation measures (closing the cave, changing the tourist route etc.). Although the disapearance of R. mehelyi colony (almost 5.000 individuals) from Liliecilor Cave in Gura Dobrogei is caused by many factors (insensive agriculture, habitat fragmentation), the most significant impact was caused by uncontrolled and easy acces granted to toursts.

With support granted by the scientific literature we consider that human activity in caves, including tourism, can have a negative impact on bats. The effects consist of (1) leaving the roost, (2) colony fragmentation in multiple caves, (3) growth in the mortality of newborn pups, (4) high mortality rate in newborn pups, (5) lowering the chance of survival of bats during hibernation. On the other hand, closing caves with bat-friendly solutions and/or reducing cave visits during both maternity (15 may-15 august) and hibernation season (1 november-31 march), can have a positive impact on bat colonies. Closing the caves isn’t always a good choice, from a financial point of view. It is also a possibility that the caves cannot or should not be completely closed, as there are some species that react negatively to cave closings (as is the case of M. schreibersii).

Based on the data collected by national specialists, we think that nowadays bat colonies in Romania are at a minimum number. Actually, the size of the colonies is kept at a minimum because of the frequent visits in shelters during hibernation and maternity seasons. We support the idea that by restricting anthropic activity, colonies will grow again at a normal and real level.

The above text, about the effects of human presence on bats, was written by members of the Romanian bat research community, with support from literature:

  • Borda D., Racoviță G., Năstase-Bucur R., Ciubotărescu C. (2010): Ecological Reconstruction of Bat Cave Roost in Western Carpathians. Sustainability of the karst environment, International Interdisciplinary Scientific Conference, Plitvice Lakes, Croatia, p. 17-24.
  • Cardiff S.G., Ratrimomanarivo F.H., Goodman S.M. (2012): The effect of tourist visits on the behavior of Rousettus madagascariensis (Chiroptera: Pteropodidae) in the caves of Ankarana, Northern Madagascar. Acta Chiropterologica 14(2): 479-490. 2012.
  • Furman A., Çoraman E., Bilgin R. (2012): Bats and tourism: a response to Paksuz and Ozkan. Oryx 46(3): 330-330.
  • Gheorghiu V., Murariu D., Borda D,  Farcas A., Chachula O. (2009): The first ecological reconstruction of the underground environment from Romania – Cioclovina Uscată Cave, chapter 3: Ecological reabilitation and restoration of the hibernating colonies of Chiroptera from Dry Cioclovina Cave. Pp. 19-60. Edit. Universitară, București. 131 pp.
  • Johnson S.A., Brack V., Rolley R.E. (1998): Overwinter weight loss of Indiana Bats (Myotis sodalis) from hibernacula subject to human visitation. The American Midland Naturalist 139(2): 255-261.
  • Kofoky A., Andriafidison D.,  Ratrimomanarivo F., Razafimanahaka H.J. , Rakotondravony D., Racey P.A., Jenkins R.K.B. (2006): Habitat use, roost selection and conservation of bats in Tsingy de Bemaraha National Park, Madagascar. Vertebrate Conservation and Biodiversity, pp 213-227.
  • Mann S.L., Steidl R.J., Dalton V.M. (2002): Effects of cave tours on breeding Myotis velifer: Journal of Wildlife Management 66(3): 618-624.
  • Olson C.R., Hobson D.P., Pybus M.J. (2011): Changes in population size of bats at a hibernaculum in Alberta, Canada, in relation to cave disturbance and access restrictions. Northwestern Naturalist 92 (3), 224-230.
  • Paksuz S., Özkan B. (2012): The protection of the bat community in the Dupnisa Cave System, Turkey, following opening for tourism. Oryx, 46(1): 130–136.
  • Petrea C., Gheorghiu V., Chachula O. (2005): Protecția și reabilitarea ecologică a unui sit subteran “Peștera Cioclovina Uscată”. Ecocarst 5-6: 46-48.
  • Speakman J.R., Webb P.I., Racey P.A. (1991): Effects of disturbance on the energy expenditure of hibernating bats. Journal of Applied Ecology 28: 1087-1104.
  • Szodoray-Parádi F., Bücs Sz., Jére Cs., Csősz I. (2014): Bat conservation measures and preliminary results in caves of NW Romania. 3rd EuroSpeleo Protection Symposium, Băile Herculane, România
  • Thomas D.W. (1995): Hibernating bats are sensitive to nontactile human disturbance. Journal of Mammalogy 76(3): 940 – 946.

What should we keep in mind when encountering bats in Nature?

We can accidentally come across bats or colonies in caves and other natural roosts (caves, potholes, hollow trees, cliff cracks) or anthropogenic shelters (abandoned mines). Our presence can have a negative impact on bats. Because we create a disturbance, bats can be forced to leave these shelters, which might have been used by the colony for centuries. Big colonies fragment into smaller ones, and take refuge in multiple caves. Also, disturbances created on maternity colonies (between 15 May and 15 August) can provoke a growth in the mortality rates of newborn pups, putting in danger the future generations.

Disturbing hibernating colonies (1 November – 31March) can lower the survival chance of bats, because they consume more fat reserves. These reserves were accumulated in autumn and have the role to insure the necessary energy to survive winter. If bats consume these reserves by coming out and in hibernation repeatedly (because of multiple disturbances), the risk of not surviving winter grows. More details about the effects of human activity on bats are presented in the upper part of the text.

Bats from Romania are protected by both national and European legislation. Protecting bats is a necessity in order for bats and colonies to survive, to insure the existence of shelters bare of disturbances and full of safety, with protected feeding and flying habitats. Protecting bats is also a necessity to humans, because of the benefits we obtain through the presence of bats.

In order to help protect bats in natural roosts, the bat research community from Romania has established 10 rules of for good-practice when encountering bats outdoors. We recommend that these rules should be passed on and respected, in order to help bats and the environment:

  1. The access into caves or other roosts should be done in order, silence and calm, in compliance with safety requirements, and without disturbing bats, by staying on marked trails or existing tourist routes, and by using only electric light sources (the use of carbide powered light sources in Romanian caves is prohibited by Decision nr. 1 of the Speleological Heritage Commission, from 12.09.2012).
  2. Proceed on trails without illuminating or photographing bats;
  3. Do NOT touch or deliberately knock down bats;
  4. Do NOT capture or try to hit bats in flight;
  5. Stay as little as possible (less than 1 minute) in the vicinity of bats;
  6. Avoid camping in the underground; if camping in caves is strictly necessary (ex. for safety reasons), camp only at distances greater than 100 meters from bats;
  7. Do NOT create smoke inside caves or other shelters, or at their entrances;
  8. At caves or other shelters, or at their entrances avoid installing and/or using equipment that produces constant and excessive noise and/or light; Exception are the personal light sources, used for staying safe;
  9. Do NOT organize events (ex. concerts, festivals, fairs, religious activities, liturgies, etc.) involving light, noise or other kinds of pollutions inside caves, or at less than 200 m of their entrances;
  10. Do NOT install infrastructure which can cause disturbance to bats, or which can cause changes in the microclimate of roosts (ex. gates, artificial walls, ditches), or which can prevent the access of bats to caves or other roosts.

In case you witness an action which results in a negative impact for bats, please contact us. Regarding intentional and unintentional destructions, significant disturbances, or which have as effect a big mortality rate for bats, and regarding non-compliances with authorizations, licenses and clearances for activities in caves or other natural shelters, the legislation in force applies the following sanctions and contraventions noted in:

  1. Law nr. 13/1993 through which Romania is ratifying the Convention on the Conservation of European Wildlife and Natural Habitats;
  2. Law nr. 13/1998 through which Romania is ratifying Convention on the Conservation of Migratory Species of Wild Animals
  3. Law nr. 90/2000 through which Romania is ratifying the Agreement onthe Conservation of Populations of European Bats (EUROBATS);
  4. Directive 2008/99/CE regarding Protection of the Environment through Criminal Law;
  5. Law nr. 49/2011 for the approval of the Government Emergency Ordinance nr. 57/2007 regarding the Status of Protected Natural Areas and the Conservation of natural habitats and wild flora and fauna;
  6. Law 205/2014 regarding Animal Protection;
  7. Lex ferenda.

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