Murina yushuensis: A new species of Tube-nosed Bat from a high altitude cave on the Tibetan Plateau.

Tube-nosed Bats, Murina spp., are a large group of Vespertilionid Bats found from northeastern Russia to Papua New Guinea. There are currently 40 described species in the genus about half of which have been described in the past decade, largely from genetic studies which have uncovered many cryptic species, predominantly in South and Southeast China. These Bats are insectivorous, and generally found in lowland forests, with the maximum known diversity in South China and Southeast Asia, although this may be due to a lack of sampling in more northerly parts of China.

In a paper published in the Journal of Mammalogy on 23 October 2024, Xiaoyun Wang of the Key Laboratory of Conservation and Application in Biodiversity of South China at Guangzhou University, Xuesong Han of the Shan Shui Conservation Center and the Center for Nature and Society at Peking University, Gábor Csorba of the Department of Zoology at the Hungarian Natural History Museum, Yi Wu, also of the Key Laboratory of Conservation and Application in Biodiversity of South China at Guangzhou University, Huaiqing Chen also of the Center for Nature and Society at Peking University, Xiang Zhao and  Zhengyi Dong, also of the Shan Shui Conservation Center, Wenhua Yu,again of the Key Laboratory of Conservation and Application in Biodiversity of South China at Guangzhou University, and Zhi Lu, again of the Center for Nature and Society at Peking University, describe a new species of Murina from a high altitude cave on the Tibetan Plateau in Qinghai Province in Northeast China.

On 15 March 2018, a Bat roosting in the entrance to a cave on the bank of the Batang River about 8 km from the city of Yushu and 3770 m above sealevel was disturbed, responding by making a long, high-pitched noise. At the time the significance of this was not realised, but when the significance was realised, several repeat visits were made, with the Bat being found again on 25 December 2018.

The new species is described from this single male specimen, and is named Murina yushuensis, where 'yushuensis' means 'from Yushu'. The single specimen is 30.44 mm long (small for a member of the genus). with dark skin and small round ears, lacking the notch seen in some members of the genus. The fur of the dorsal surface is about 10 mm in length, with the basal 7 mm being black in colour, and the 3 mm at the tip being a golden brown. The fur of the ventral surface is slightly shorter, which the basal black portion being about 6 mm, and the 3 mm of the tip being pale. 

Holotype specimen of Murina yushuensis, GZHU 20077. Wang et al. (2024).

The Batang River is a tributary of the Yangtze running across the Tibetan Plateau, at altitudes of between 3860 m and 3530 m above sealevel. The area where Murina yushuensis was discovered has a mean annual temperature of only 2.9°C, and an annual average precipitation of 487 mm. The vegetation is largely meadows of Feathergrass with scattered shrubs and patches of Juniper woodland. This is a distinctly unusual environment for a member of a genus usually found in lowland tropical and subtropical forests. Murina yushuensis was discovered at the highest altitude any member of the genus has ever been recorded at, with the previous record being a specimen of the Little Tube-nosed But, Murina aurata, found at 2500 m. However, Wang et al. consider that while Murina yushuensis may seem exceptional, it is also potentially an indicator that other species of the genus may be living at high and intermediate altitudes, and not yet discovered due to a lack of sampling.

Surrounding environment of the cave where Murina yushuensis was discovered in March 2018. Wang et al. (2024).

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Outbreak of Marburg Virus reported in Rwanda.

On 27 September 2024 the  Rwanda Ministry of Health confirmed that an outbreak of Marburg Virus Disease was present in the country, following the detection of the Virus in the blood of two patients by real-time reverse transcription polymerase chain reaction analysis at the National Reference Laboratory of the Rwanda Biomedical Center, according to a press release issued by the World Health Organization on 30 September 2024.

As of 29 September 2024, 26 cases of the disease have been reported in seven of the country's thirty districts (Gasabo, Gatsibo, Kamonyi, Kicukiro, Nyagatare, Nyarugenge and Rubavu), with eight people having died of the disease, a case fatality rate of 31%. The majority of the patients are healthcare workers from two health facilities in Kigali; this is not uncommon with outbreaks of the Marburg and Ebola viruses, with the highly transmittable nature of these diseases often resulting in aa high mortality rate in healthcare workers around the initial locus of the outbreak.

Contract tracing has led to the screening of about 300 contacts of diagnosed patients, one of whom had travelled to Belgium, with all found to be healthy and not a threat to public health. The initial source of the outbreak is still under investigation.

Marburg Virus Disease is a haemorrhagic fever, similar to the closely related Ebola Virus Disease. Both are caused by single-strand negative-sense RNA viruses of the Filoviridae family. Both are easily spread though contact with bodily fluids, and can also spread by contaminated clothing and bedding. 

Negative stained transmission electron micrograph of a number of filamentous Marburg Virions, which had been cultured on Vero cell cultures, and purified on sucrose, rate-zonal gradients. Erskine Palmer/Russell Regnery/Centers for Disease Control and Prevention/Wikimedia Commons.

Marburg Virus has an incubation period of between two and 21 days, manifesting at first as a high fever, combined with a severe headache and a strong sense of malaise. This is typically followed after about three days by severe abdominal pains, with watery diarrhoea and vomiting. In severe cases the disease develops to a haemorrhagic stage after five-to-seven days, manifesting as bleeding from some or all bodily orifices. This typically leads to death on day eight or nine, from severe blood loss and shock. There is currently no treatment or vaccine available for Marburg Virus, although a number of teams are working on trying to develop vaccines. 

Previous outbreaks of Marburg Virus have been reported in Rwanda, as well as the neighbouring Democratic Republic of Congo and Tanzania. The Virus has also been reported in a number of other African countries, including Angola, Equatorial Guinea, Ghana, Guinea, Kenya, and South Africa. The most recent outbreaks occurred in January 2023, with unrelated epidemics in Tanzania and Equatorial Guinea. 

The high rate of infection of healthcare workers seen in Marburg Virus is particularly alarming, as this tends to weaken communities ability to resist the Virus. The Virus can spread quickly in healthcare settings, infecting people whose immune systems are already stressed by other conditions, and creating aa reserve which can feed infections in the wider community. This makes it important to screen all people potentially infected with the disease as quickly as possible, and to arrange for patients to be treated in isolation, as well as quickly tracing all known contacts of any cases, and screening them for infection too.

Marburg Virus is a zoonotic infection (disease transferred from Animals to Humans), with a wild-reserve of the Virus known to be present in Egyptian Fruit Bats, Rousettus aegyptiacus, which are found across much of Africa, the Mediterranean region, the Middle East, and South Asia. These Bats form large colonies in caves or sometimes mines. They are frugivores, and can be major pests of farmed fruits, bringing them into conflict with Humans, and are sometimes hunted for food, all of which create potential avenues for the Marburg Virus to pass from a Bat host to a Human one.

A colony of Egyptian Rousette Bats, Rousettus aegyptiacus. Giovanni Mari/Flikr/iNaturalist.

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Myotis nustrale: A new species of Mouse-eared Bat from Corsica.

During the past three decades, the application of genetic methodologies to taxonomy has revolutionised our understanding of the world's biodiversity, with many widespread 'species' now recognised as groups of closely related, but nevertheless distinct, cryptic species, with much more restricted distributions. This in turn has implications for the ecology and conservation of these species, with species thought to be widespread and environmentally tolerant turning out to be groups of species, each of which has a limited distribution and a narrow ecological range.

One group for which this has been found to be true are Mouse-eared Bats, Myotis spp., which were once thought to be a single species, ranging from Western Europe and North Africa through the Middle East and Central Asia as far east as Korea and Japan, but which have now been shown to be a series of morphologically similar species with more limited populations.

In a paper published in the journal Revue suisse de Zoologie on 18 October 2023, Sébastien Puechmaille of the University of Montpellier, the Institut Universitaire de France, the Groupe Chiroptères de Midi-Pyrénées, and the Zoological Institute and Museum at the University of Greifswald, Serena Dool, also of the Groupe Chiroptères de Midi-Pyrénées, and the Zoological Institute and Museum at the University of Greifswald, Gregory Beuneux of the Groupe Chiroptères Corse, and Manuel Ruedi of the Muséum d’histoire naturelle de Genève, describe a new species of Mouse-eared Bat from Corsica.

The new species is named Myotis nustrale, where 'nustrale' means 'ours' in the Corsican language. It is described largely on the basis of inspection of living specimens, and comparison of genetic material taken from tissue samples to that of Mouse-eared Bats from other populations. The designated holotype is a female specimen found dead by Julien Barataud in July 2006 and preserved in alcohol, although this is noted to be in a poor state. Physically, all examined specimens of Myotis nustrale were identical to examined specimens of Myotis nattereri and Myotis crypticus in that a small black spot on the lower lip was retained into adulthood, while it was present only in juvenile members of the other species.

External characters of Myotis nustrale. Panels are close-ups of the female holotype (MNHN-ZM-2023-12), except the lower right one which is a picture from a released adult individual. The upper left panel illustrates the stiff hairs running along the uropatagium, viewed from below. The upper right panel is the right foot with wing insertion to the base of the outer toe, in ventral view. The lower left panel illustrates the long and straight tragus and unnotched ear of the female holotype. On the portrait of the live individual, notice the black chin spot on the lower lip. Puechmaille et al. (2023).

Despite its morphological similarity to other species, Myotis nustrale is clearly genetically distinct, forming a sister taxon to a clade which includes Myotis escalerai, Myotis zenatius, Myotis schaubi, Myotis tchulliensis, Myotis nattereri, Myotis hoveli, and Myotis crypticus. Myotis nustralei shows signs of long genetic isolation from other species, which at first sight might be connected to its island endemic status, although this is actually difficult to relate to our current understanding of the behaviour of Bats of the genus Myotis. Corsica, with its own species of Myotis is 50 km from the island of Elba, which in turn is 10 km from the Italian mainland. Ireland is 78 km from the island of Great Britain, which is in turn 33 km from the European mainland, but specimens of Myotis nattereri from Ireland, Great Britain, and Europe show little genetic differentiation. Similarly, Myotis hoveli is found on the Anatolian Peninsula and the island of Cyprus, separated by 69 km, and Myotis escalerai is found on the Iberian Peninsula, and the islands of Ibiza, 86 km from the mainland, Mallorca, 81 km from Ibiza, and Menorca, 36 km from Mallorca.

Bayesian topology based on five partitioned nuclear introns (SLC38A7, ABHD11, ACOX2, COPS7A and ROGDI). The outgroup (Pipistrellus pipistrellus) is not shown. Bayesian posterior probabilities (BPP) lower than 60 are not shown, neither are within species BPP values. The holotype of Myotis nustrale (sample number MNA008_CO_ALB) is indicated by a white arrow. Puechmaille et al. (2023).

Several female Myotis nustrale were equipped with radio transmitters, and tracked during spring and summer. They spent most of their time in mountainous regions more than 500 m above sealevel, although they did occasionally come close to sea level. Hunting was carried out within 8 km of the Bat's roosts, in dense maquis scrubland with stands of Evergreen Oak, Quercus ilex, and Ash, Fraxinus spp., or open forests with Corsican Pines, Pinus nigra, surrounded by Ferns.

Portraits and hind feet (dorsal view) of an adult female Myotis nustrale caught near Bavella, in southern Corsica (left) and an adult female Myotis crypticus from the Jura mountains in Switzerland (right). Notice that the latter individual has a faint line bordering the lower lip, while the former has a much more conspicuous chin spot. Wing insertion to the outer toe is, however, identical in both species. For the left individual, the wing was not stretched while it was stretched for the right individual. Puechmaille et al. (2023).

Myotis nustrale is restricted to the island of Corsica, and apparently to a small region within the Parc Naturel Régional de Corse, largely at altitudes of between 500 m and 2000 m above sealevel. The limited distribution and small population of the species would seem to make it particularly vulnerable to climate change, as the only response the Bats would have to a warming climate, would be to move upwards, leading to increased population fragmentation. 

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Marburg Virus alert in Guinea comes to an end.

The Ministry of Health of Guinea has declared the end of the Marburg Virus Disease outbreak in Guéckédou Prefecture, Nzérékoré Region, according to a press release issued by the World Health Organization on 17 September 2021. In accordance with World Health Organization recommendations, the declaration was made 42 days after the safe and dignified burial of the only confirmed patient reported in this outbreak. This was the first-ever Marburg Virus Disease case reported in Guinea. 

On 16 September 2021, the Ministry of Health of Guinea declared the end of the Marburg virus disease outbreak in Guéckédou prefecture, Nzérékoré Region. In accordance with World Health Organization recommendations, the declaration was made 42 days after the safe and dignified burial of the only confirmed patient reported in this outbreak. This was the first-ever Marburg virus disease case reported in Guinea.

From 3 August 2021 to the end of outbreak declaration, only one confirmed case was reported.  The patient, a man, had onset of symptoms on 25 July. On 1 August he went to a small health facility near his village, with symptoms of fever, headache, fatigue, abdominal pain and gingival hemorrhage. A rapid diagnostic test for Malaria returned a negative result, and the patient received ambulatory supportive care with rehydration and symptomatic treatment. Upon returning home, his condition worsened, and he died on 2 August. An alert was subsequently raised by the sub-prefecture public health care facility to the prefectorial department of health in Guéckédou. The investigation team was immediately deployed to the village to conduct an in-depth investigation and collected a post-mortem oral swab sample, which was shipped on the same day to the Viral Hemorrhagic Fever Laboratory in Guéckédou city. On 3 August, the sample tested positive for Marburg Virus Disease by reverse transcriptase-polymerase chain reaction and negative for Ebola Virus Disease. The deceased patient was buried safely and with dignity on 4 August, with the support of the national Red Cross.

On 5 August, the National Reference Laboratory in Conakry provided confirmation by real-time polymerase chain reaction of the positive Marburg result, and on 9 August, the Institut Pasteur Dakar in Senegal provided an additional confirmation that the result was positive for Marburg Virus Disease and negative for Ebola Virus Disease.

 

Negative stained transmission electron micrograph of a number of filamentous Marburg Virions, which had been cultured on Vero cell cultures, and purified on sucrose, rate-zonal gradients. Erskine Palmer/Russell Regnery/Centers for Disease Control and Prevention/Wikimedia Commons.

The Ministry of Health activated the national and district emergency management committees to coordinate the response and engage with the community. Additionally, the Ministry of Health together with the World Health Organization, the United States Centers for Disease Control, the Alliance for International Medical Action, the Red Cross, UNICEF, the International Organization for Migration, and other partners, initiated measures to control the outbreak and prevent further spread including the implementation of contact tracing and active case search in health facilities and at the community level.

During the outbreak, a total of one confirmed case who died, and 173 contacts were identified, including 14 high risk contacts based on exposure. Among them, 172 were followed for a period of 21 days, of which none developed symptoms. One high-risk contact was lost to follow up. At the different points of entry in Guéckédou prefecture where passengers were screened, no alerts were generated.

Ongoing activities include:  Capturing and sampling of Bats in the localities of Temessadou M´Boké, Baladou Pébal and Koundou to better understand the involvement of Bats in the ecology of Marburg Viruses; development of a sero-surveillance protocol in the sub-prefecture of Koundou; development and implementation of plans to strengthen Infection Prevention and Control programmes at the national and facility level including establishing and mentoring of Infection Prevention and Control focal persons, Infection Prevention and Control/hygiene committees, ongoing training of health workers and adequate procurement and distribution of supplies such as personal protective equipment; implementation of water, sanitation and hygiene measures with partners including in health facilities and communities; supporting training on community-based surveillance in Guéckédou Prefecture; and risk communication and community mobilization activities in Guéckédou Prefecture as a component of a health emergency preparedness and response action plan. 

 

A health worker in Gueckedou, Guinea. World Health Organization.

Marburg Virus Disease is an epidemic-prone disease associated with high case fatality ratios (24-90%). In the early course of the disease, clinical diagnosis of Marburg Virus Disease is difficult to distinguish from many other tropical febrile illnesses, because of the similarities in the clinical symptoms. Other viral hemorrhagic fevers need to be excluded, particularly Ebola Virus Disease, as well as Malaria, Typhoid Fever, Leptospirosis, Rickettsial infection and Plague. Marburg Virus Disease is transmitted by direct contact with the blood, bodily fluids and/or tissues of infected persons or wild Animals (e.g. Monkeys and Fruit Bats).

Investigations are ongoing to identify the source of the infection. Guinea has previous experience in managing viral hemorrhagic diseases such as Ebola Virus Disease and Lassa Fever, but this was the first time that Marburg Virus Disease was reported. The country has a fragile health care system due to the overburden of disease outbreaks, COVID-19 pandemic, and the recurrent threat of epidemics such as Malaria, Yellow Fever, Measles, Lassa Fever, Ebola Virus Disease, health care-associated infections, high rates of acute malnutrition, cyclical natural disasters such as floods, and socio-political unrest.

Guinea health authorities responded rapidly to the event, and measures were rapidly implemented to control the outbreak. Cross-border population movement and community mixing between Guinea and neighboring Sierra Leone and Liberia increased the risk of cross-border spread. Sierra Leone and Liberia health authorities activated contingency plans and started public health measures at the points of entry with Guinea.

The affected village is in a remote forest area located at the border with Sierra Leone, about 9 km from a main international border crossing point between the two countries. The proximity of the affected area to an international border, cross-border movement between the affected district and Sierra Leone, and the potential transmission of the Virus between Bat colonies and Humans posed an increased risk for cross-border spread. 

These factors suggested a high risk at the national and regional level, and given that Guéckédou Prefecture is well connected to Foya District in Liberia, and Kailahun District in Sierra Leone, this outbreak required an immediate and coordinated response with support from international partners. The risk associated with the event at the global level was assessed as low. 

Human-to-Human transmission of Marburg virus is primarily associated with direct contact with blood and/or bodily fluids of infected persons, and Marburg Virus transmission associated with the provision of health care has been reported when appropriate infection control measures have not been implemented. 

Health care workers caring for patients with suspected or confirmed Marburg Virus Disease should apply standard and transmission-based infection prevention and control precautions to avoid any exposure to blood and/or bodily fluids, as well as unprotected contact with the possibly contaminated environment. Infection prevention and control precautions include: Early recognition (screening, triage) and isolation of suspected cases; appropriate isolation capacity (including infrastructure and human resources); health care workers’ access to hand hygiene resources (i.e., soap and water or alcohol-based hand rub); appropriate and accessible personal protective equipment for health care workers; safe infection practices (emphasise on single-use only needles); procedures and resources for decontamination and sterilisation of medical devices; and appropriate management of infectious waste.

Infection prevention and control  assessments of health facilities in affected areas using the Infection Prevention and Control Scorecard revealed sub-optimal results highlighting the need for ongoing supportive supervision and mentorship for implementation of infection prevention and control in health care settings in addition to implementing infection prevention and control minimum requirements to support and strengthen future preparedness for emerging and re-emerging infectious diseases. 

Integrated disease surveillance and response activities, including community-based surveillance must continue to be strengthened within all affected health zones.

Raising awareness of the risk factors for Marburg Virus Disease and the protective measures individuals can take to reduce human exposure to the virus are the key measures to reduce Human infections and deaths. Key public health communication messages include: Reducing the risk of Human-to-Human transmission in the community arising from direct contact with infected patients, particularly with their bodily fluids; avoiding close physical contact with patients who have Marburg Virus Disease; a ny suspected case ill at home should not be managed at home, but immediately transferred to a health facility for treatment and isolation. During this transfer, health care workers should wear appropriate personal protective eqipment; regular hand washing should be performed after visiting sick relatives in hospital; and communities affected by Marburg should make efforts to ensure that the population is well informed, both about the nature of the disease itself to avoid further transmission, community stigmatisation, and encourage early presentation to treatment centers and other necessary outbreak containment measures, including safe burial of the dead. People who have died from Marburg should be promptly and safely buried.

To reduce the risk of wildlife-to-Human transmissions, such as through contact with Fruit Bats, Monkeys, and Apes: Handle wildlife with gloves and other appropriate protective clothing; cook Animal products such as blood and meat thoroughly before consumption and avoid consumption of raw meat; and during work, research activities or tourist visits in mines or caves inhabited by Fruit Bat colonies, people should wear gloves and other appropriate protective clothing including masks.

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Guinea reports the first ever case of Marburg Virus in West Africa.

Health authorities in Guinea have confirmed a case of Marburg Virus disease in Gueckedou Prefecture in the Nzérékoré Region of southern Guinea. This is the first time Marburg, a highly infectious disease that causes haemorrhagic fever, has been identified in the country, and in West Africa, according to a press release issued by the World Health Organization on 9 August 2021.

Marburg, which is in the same family as the virus that causes Ebola, was detected less than two months after Guinea declared an end to an Ebola outbreak that erupted earlier this year. Samples taken from a now-deceased patient and tested by a field laboratory in Gueckedou as well as Guinea’s National Haemorrhagic Fever Laboratory turned out positive for the Marburg virus. Further analysis by the Institut Pasteur in Senegal confirmed the result.

 

A health worker in Gueckedou, Guinea. World Health Organization.

The patient had sought treatment at a local clinic in Koundou area of Gueckedou, where a medical investigation team had been dispatched to probe his worsening symptoms.

'We applaud the alertness and the quick investigative action by Guinea’s health workers. The potential for the Marburg virus to spread far and wide means we need to stop it in its tracks,' said Matshidiso Moeti, the World Health Organization's Regional Director for Africa. 'We are working with the health authorities to implement a swift response that builds on Guinea’s past experience and expertise in managing Ebola, which is transmitted in a similar way.'

Gueckedou, where Marburg has been confirmed, is also the same region where cases of the 2021 Ebola outbreak in Guinea as well as the 2014–2016 West Africa outbreak were initially detected.

Efforts are underway to find the people who may have been in contact with the patient. As the disease is appearing for the first time in the country, health authorities are launching public education and community mobilisation to raise awareness and galvanize support to help curb widespread infection.

An initial team of 10 World Health Organization experts, including epidemiologists and socio-anthropologists is on the ground helping to investigate the case and supporting the national health authorities to swiftly step up emergency response, including risk assessment, disease surveillance, community mobilization, testing, clinical care, infection prevention as well as logistical support.

Cross-border surveillance is also being enhanced to quickly detect any cases, with neighbouring countries on alert. The Ebola control systems in place in Guinea and in neighbouring countries are proving crucial to the emergency response to the Marburg virus.

Marburg is transmitted to people from Fruit Bats and spreads among Humans through direct contact with the bodily fluids of infected people, surfaces and materials.

Illness begins abruptly, with high fever, severe headache and malaise. Many patients develop severe haemorrhagic signs within seven days. Case fatality rates have varied from 24% to 88% in past outbreaks depending on Virus strain and case management.

Although there are no vaccines or antiviral treatments approved to treat the virus, supportive care, rehydration with oral or intravenous fluids, and treatment of specific symptoms, improves survival. A range of potential treatments, including blood products, immune therapies and drug therapies, are being evaluated.

In Africa, previous outbreaks and sporadic cases have been reported in Angola, the Democratic Republic of the Congo, Kenya, South Africa and Uganda.

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Nyctalus noctula: The discovery of a mass-wintering site used by the Common Noctule Bat in a town in southeast Poland.

The Common Noctule Bat, Nyctalus noctula, (Vespertilionidae) is amongst the Bat species with the longest seasonal migrations at distances as far as 1600 km. Particularly, long passages have been noted in Eastern Europe, which is characterised by longer and relatively cooler winters. Several decades ago, this Bat species was considered a regularly migrating species in Poland, particularly in the eastern part of the country. According to Petr Petrovič Strelkov the species selects areas of mean air temperature in January above –3°C for its wintering grounds. Large winter roosts have been known in Germany, where over 10 000 of hibernating Common Noctules have been found in some places.

In recent years, the number of winter records of the Common Noctule has markedly increased in Poland. Wintering of this species was noted in the central and eastern parts of the country. Increasing colonisation of urban areas and markedly enhanced sedentariness of this species was described for some places in Central Europe. Having this in mind, one may expect to find a greater number of winter roosts of the Common Noctule in Poland.

In a paper published in the journal Acta Zoologica Bulgaria on Grzegorz Lesiński and Krzysztof Janus of the Institute of Animal Sciences at the Warsaw University of Life Sciences, present the results of a study carried out in Nowy Sącz, a town in southeast Poland (83 000 inhabitants), in which a new mass-wintering site used by the Common Noctule Bats was discovered.

The study was carried out in two residential buildings built of concrete slabs. The five-storey buildings have been insulated with Styrofoam. Between the highest floors and the flat roofs of the buildings, there are low attics (with maximum height of 80 cm). Their floor has been insulated with mineral wool.

 

Building with the common noctule flying out of the attic. Arrows indicate some outlets from the attic. Lesiński & Janus (2020).

Nowy Sącz is situated in the flat bottom of the Sądecka Valley between the Dunajec River and its tributary the Kamienica Nawojowska River at an elevation from 272 to 475 m above sealevel (Majdan Hill). The town is located at the foothill of mountain ridges: Beskid Sądecki to the south, Beskid Wyspowy to the west, Beskid Niski to the east and Pogórze Rożnowskie to the north. At a short distance from the town, is the Rożnowskie Lake. The surface area of the town is 58 km² and the geographic coordinates of the housing estate are 49°37′30″ N, 20°41′44″ E.

A detailed survey of the buildings was made on 23 April, 20 July and 20 November 2014. All walls were observed with particular attention paid to cracks and openings in the walls (especially those with visible smudges of dirt and fat left by rubbing Animals), air holes and surroundings of window sills, gutters and drainpipes. Much attention was paid to the edges of metal sheets on roofs (frequent places of hiding). Marks of the presence of Bats (faeces) were searched for near the buildings. Attics were also surveyed.

Evening counting of bats flying out of attics was done on 17 September 2014. Observation of Bats leaving their daily shelter started two hours before dusk. Every flying individual was recorded and the time of start and end of Bats’ flying out of the attic was noted. Bats were identified considering their size and silhouette. Additional monitoring was performed with ultrasonic detector LunaBat DFD-1 operating in the system of frequency division. Sounds were recorded with digital sound recorder Samson Zoom H1.

Detailed survey of whole attics was made in only two buildings (Building 1 and Building 2). In other two buildings, parts of attics were surveyed on 10 February 2015. In many other buildings, studies were not possible due to unavailability of attics, which entrances were bricked up.

Counting Bats flying out of attics of two buildings just before hibernation (on 17 September 2014) revealed the presence of 546 individual Common Noctules. No other Bat species were recorded. The flight of Common Noctules took place early before dusk. The time of flying out of the attic of the Building 1 was determined for 252 individuals. The first individual flew out 50 minutes before sunset and the last one 10 minutes before sunset. The greatest intensity of flying was noted from 47 to 32 minutes before sunset. 

 

The number of Common Noctules flying out of attic in relation to the time (in minutes) before sunset (252). Lesiński & Janus (2020).

In total, 905 wintering individual Common Noctules were recorded during the survey of attics on 20 November 2014. Bats stayed on the walls of attics and on mineral wool lining the floor. Those on walls formed groups of up to 30 individuals. Moreover, surveys made on 10 February 2015 in two other buildings revealed the presence of about 230 hibernating individuals. Roosts in attics were also inhabited by Common Noctules during the reproduction period. Their number was, however, notably lower. In a single building no more than 50 individuals were present.

 

Individuals of the Common Noctule hibernating on mineral wool in building’s attic. Lesiński & Janus (2020).

Having in mind that detailed studies covered only two buildings out of 65 similar buildings in this housing estate in Nowy Sącz, Lesiński and Janus expect that several times more bats than actually observed are wintering there. During observations in September, Bats flying out of attics were noted not only from the two analysed buildings but also from several others in the neighbourhood. If other buildings were occupied by similar number of Bats, then their total number in the housing estate might be estimated at several thousand. Wintering of this species in similar buildings has also been noted in the town of Prešov (Slovakia), situated 80 km south of Nowy Sącz. So far, the nearest finding of wintering Common Noctules recorded was in Krynica (about 30 km south-east of Nowy Sącz), where one individual survived the winter of 2005/2006 in the attic of an Orthodox church. Lesiński and Janus do not exclude the possibility of other winter roosts of the common noctule in buildings in the regions of southern Poland and north-eastern Slovakia.

 

A cluster of the Common Noctule hibernating in an attic. Lesiński & Janus (2020).

Since the number of Bats occupying buildings in Nowy Sącz during reproduction is much lower than those wintering there, Lesiński and Janus expect that most wintering bats fly in from other areas. However, there are no data on the distances of their flights. An indication of how long such flights might be an example of a Common Noctule ringed in a winter roost in Slovakia and found next summer in the Białowieża Forest, north-eastern Poland. It is thus possible that buildings in Nowy Sącz serve as a winter roost for Bats inhabiting regions several hundred kilometers away. These might be the areas of eastern Poland but also in the Baltic republics and Belarus.

The described case of mass wintering of Common Noctules is certainly not exceptional and further studies should allow for finding other large winter roosts of Nyctalus noctula in Poland. Such findings may be expected also in cooler regions of the country, especially if global climate change will proceed. The threshold mean temperature in January (–3°C) that enables wintering of the Common Noctule has been recently confirmed in central and partly in eastern regions of Poland. Recently Common Noctules succesfully hibernated even in poorly isolated place (balcony) in Warsaw, central Poland.

The increasing number of winter roosts of the Common Noctule found in Central Europe confirms the deeper penetration of its populations into towns in search for shelters in buildings. With increasing trend of global climate change, these Bats could show enhanced sedentariness and likely hibernate in areas, from where they flew for wintering over 1000 km away several decades ago.

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