Bat activity lower at solar farm sites, study finds
The activity level of six bat species was significantly reduced at solar farm sites, researchers have observed.
Their findings, published today in Journal of Applied Ecology, have the potential to impact and inform planning legislation and policy so that the benefits of solar power are reaped without impacting wildlife.
Renewable technologies are important in meeting energy demands sustainably. This is of vital importance given the roles of fossil fuels in producing carbon dioxide, a key driver of climate change. Renewable energy is growing at a rapid pace globally, with solar photovoltaic power providing about 30% of global renewable power, and increasing in amount by 25% in 2021.
Lead author Lizy Tinsley from the University of Bristol’s School of Biological Sciences explained: “Renewable energies can have negative impacts on biodiversity and mitigation is essential to provide win-win solutions for energy suppliers and for wildlife.”
To carry out their experiment, the team set up bat static monitoring equipment in a solar farm field, and a matched field without solar panels (control site).
Fields were matched in size, land use, and boundary feature (e.g. hedge, fence, stream) and a bat detector was placed in the middle and edge of both fields, totalling four recording locations, repeated across 19 separate sites. Field boundaries were selected as they are important navigation features for bats.
The data from the different echolocation calls at recording points were then analysed to identify the bat species and number of bat passes. They found that the activity level of Common Pipistrelle, Noctule, Myotis species, Serotine, Soprano pipistrelle and Long-eared species was substantially lower at solar farm sites, compared to the paired control sites.
Lizy said: “Due to the significant negative impact identified, solar farm developments should be screened in an Environmental Impact Assessment for ecological impacts so that appropriate mitigation be designed against the impacts, and monitoring undertaken.
“This has already been done with wind farms – where mortality of bats has been reduced by changing the wind speeds at which turbines become operational and by using acoustic deterrents, at minimal cost.
“Further research is required to assess bat behaviour at solar farms, and why it is causing the significant decrease of certain species at the site. Is it the loss of suitable habitat that reduces activity? Are they fewer insect prey available, and are bats at risk of collisions with panels?
“It will be important to identify mitigation strategies that can benefit bats at solar farms, such as planting insect-friendly plants, providing corridors to insect-rich habitats, or providing suitable alternative foraging habitats such as trees.
“Mitigation strategies can potentially mean that renewable energy can be provided while simultaneously having no detriment to wildlife. Such mitigation will be critical in reaping the undoubted benefits for climate change that can be provided by renewable energy.”
Co-author Professor Gareth Jones added: “This is novel research, as the impacts of solar farms on wildlife are currently little understood, with no evidence regarding their effects on bats, which can provide valuable ecosystem services such as the suppression of pest insect populations.
“The situation is potentially of concern as solar farms are occupying increasing areas of suitable foraging area for bats, and we already know that bats can collide with vertical flat surfaces, and can mistake flat surfaces for water, and attempt to drink from them. Very little is known on the impacts of solar farms on bat, particularly in the UK.”
The team now plan to look at the differences in invertebrate species richness and abundance between the paired sites.
Illustration showing effect of solar farming on bat activity
CREDIT
Lizy Tinsley
JOURNAL
Journal of Applied Ecology
ARTICLE TITLE
‘Renewable energies and biodiversity: impact of ground-mounted solar photovoltaic sites on bat activity’
ARTICLE PUBLICATION DATE
8-Aug-2023
Common ancestors of bats were omnivorous suggested by resurrection of ancestral sweet receptors
This study is led by Prof. Huabin Zhao (College of Life Sciences, Wuhan University).
The origins of powered flight and laryngeal echolocation in bats are widely cited as evidence that ancestral bats evolved as insectivores. Moreover, others have hypothesis that suggesting early bats were diurnal herbivores and that insectivory emerged secondarily for protein supplementation, which suggests modern frugivorous and nectarivorous bats might have retained ancestral adaptations, rather than undergone derived specializations. Direct evidence relating to the diets of ancestral bats is lacking.
Taste is closely linked to diet, and the sweet taste is particularly tied to the consumption of carbohydrate. The sweet taste receptor is formed by a dimer of Tas1r2 and Tas1r3, encoded by the Tas1r2 and Tas1r3 genes, respectively. In a previous study, both in vivo and in vitro functional experiments indicated that frugivorous species from both suborders of bats can sense natural sugars, whereas insectivorous species cannot.
To obtain insights into early evolution of bats, this study assesses whether ancestral bats were able to sense natural sugars, by resurrecting and measuring the functional properties of ancient proteins from six ancestral linages. The sweet receptors of the common ancestors of all extant bats, Yinperochiroptera, and Pteropodidae showed clear responses to natural sugars.
Functional assays of mismatched sweet receptors indicated that Tas1r2 is responsible for the loss of sweet taste in the ancestor of Yangochiroptera, and both Tas1r2 and Tas1r3 have resulted in the regain of the sweet taste in a New World fruit bat.
Two sets of protein sequences respectively resurrected by the amino acid model and the codon model showed the same trend in functional assays. Clear responses to an artificial sweetener as a positive control and similar equivalent expression levels of Tas1r2 and Tas1r3 confirmed that the heterologous expression system worked properly.
In summary, these findings provide the first evidence that the ability to sense natural sugars was present in the common ancestors of extant bats. Based on the correspondence between taste and diet in extant bats, early bats were suggested as omnivorous, feeding on a mixture of fruits and insects, and the ability to preceive sweetness has been retained throughout the evolutionary history of Old World fruit bats. The omnivorous diet of the common ancestor of bats challenges the common view that bats evolved flight and echolocation for hunting insects. Instead, it raises the possibility that the first bats hunted for insects and fruit without echolocation.
“This is an interesting study that went an additional step in inferring ancestral phenotypes from ancestral genotypes.” Says Professor Jianzhi George Zhang, the former President of Society for Molecular Biology and Evolution and Fellow of the American Association for the Advancement of Science, an evolutionary geneticist at the University of Michigan. “In this work, the authors inferred the dietary preference of the common ancestor of all extant bats by experimentally confirming the functions of inferred ancestral taste receptor genes, rendering their phenotypic inference more trustworthy. Because the diet of ancestral bats is hypothesized to be linked with the evolution of bat flight and echolocation, this study will stimulate investigations of the origin of bats and their unique biology.” Zhang says.
“This is an exciting new study where the authors reconstructed the taste receptors from ancestral bats using evolutionary methods to uncover how bat's feeding behaviours evolved.” Says Professor Emma Teeling, the member of Royal Irish Academy, a zoologist at the University College Dublin, Ireland. “One particularly interesting observation is that potentially New World fruit-feeding bats have evolved a different way to taste natural sugars, which would provide a new avenue for mammalian sensory biology. This study is an exciting example of the use of functional genomics to link genotype and phenotype together, giving us a unique insight into the evolution of bats’ unique sensory biology not possible before.” Teeling adds.
See the article:
JOURNAL
Science Bulletin
DOI
The war-damaged urban environment in Kharkiv is fatal for bats
Loss of roosts and lethal traps in destroyed buildings
Peer-Reviewed PublicationRussia’s war in the Ukraine has severe consequences not only for humans, it also has detrimental effects on populations of urban and semi-urban wildlife in the attacked cities and regions. Scientists from the Ukrainian Bat Rehabilitation Center recently examined the effects of war-related damages to buildings on urban populations of one important and widespread bat species, the Common Noctule (Nyctalus noctula), in the city of Kharkiv in north-eastern Ukraine. They showed that many buildings used by bats as roosts have been destroyed and approximately 7,000 bats were killed. In addition, partially destroyed buildings have become a death trap for bats, resulting in several thousand more victims. The findings are published in the Journal of Applied Animal Ethics Research.
The mission of the Ukrainian Bat Rehabilitation Center (UBRC) is to protect, rescue and conduct long-term research on bats, with the Kharkiv region as the focus of their efforts. Kharkiv is Ukraine’s second largest city and one of the places where conflicts between Ukrainian and Russian forces have been most intense to date. UBRC director Dr Anton Vlaschenko, who is also affiliated with the Berlin-based Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW), says: “Our findings suggest that 45.1% of buildings used as wintering roosts for Common Noctules were either partially damaged or completely destroyed by shellings, which may have led to the direct killing of approximately 7,000 bats.” Additionally, the war-damaged urban environment in Kharkiv has become a deadly trap for the bats during the period of autumn migration or swarming. “Bats entered the interiors of buildings through windows that were left open or broken by blast waves, resulting in entrapment,” says former Leibniz-IZW PhD student Dr Kseniia Kravchenko from the UBRC.
Windows left open by people and/or were broken by blast waves are a notable threat for migratory bats that enter the building and get trapped inside the apartments or between window frames. Some of the windows in the city are of an old double-glazed type – two frames with a space between them – and the bats end up trapped in the middle. “The issue has been known to occur in Kharkiv since the 1960s, but the war exacerbates the problem by creating ever more human-made traps for bats,” reports Vlaschenko . Before the war, UBRC scientists used to rescue up to 500 bats from such windows during the autumn bat migration. Owing to the war, the number of cases of bats trapped in partially damaged buildings and/or abandoned apartments was three times higher than in previous years. Almost all of them were Common Noctules. The team reports that they discovered 2,836 Common Noctules trapped inside buildings damaged by shelling and that approximately 30 percent of them were already dead upon discovery. Noctules flies in groups and these groups can get lost in urban structures. The size of trapped groups was clearly larger than in previous years, especially in the districts of the city most damaged by the ongoing war such as Saltivka,” says Kravchenko. During the first weeks of the full-scale war (February–March 2022) alone, almost half of the buildings known as winter roosts of Common Noctules were partially (31.4%) or fully (13.7%) damaged by Russian shelling, which may have led to the direct killing of thousands of bats.
The number of bats present in Kharkiv in 2022 was exceptional high, as Common Noctules stayed in the Kharkiv city area all autumn. The scientists also found that these bats had a larger body mass than usual. These changes might have been a consequence of the destruction of street lights and power plants in Kharkiv and most of the settlements in Ukraine since the beginning of the war. The absence of artificial light might result in more bats entering the city, as this removed any “light barrier” for nocturnal animals and facilitated a rapid recovery of night-active insect populations.
“The war created many new challenges in our lives and to those of bats, but we don’t lose focus on our mission to protect wildlife and exploit the current context to learn as much as we can on our favourite animals”, concludes Vlaschenko. The war has indeed made their working condition extremely difficult, but the team of the Ukrainian Bat Rehabilitation Center remains very active and continues to save bats, gather data, run workshops and collaborate with many scientists and institutes in Ukraine and beyond, such as with the Leibniz-IZW.
Publication
Vlaschenko A, Shulenko A, But A, Yerofieiva M, Bohodist V, Petelka M, Vovk A, Zemliana K, Myzuka D, Kravchenko K, Prylustka A (2023): The War-Damaged Urban Environment Becomes Deadly Trap for Bats: Case from Kharkiv City (NE Ukraine) in 2022. Journal of Applied Animal Ethics Research, 5(1), 27-49. DOI: 10.1163/25889567-bja10035
Contacts
Anton Vlaschenko
Director of the Ukrainian Bat Rehabilitation Center, Ukrainian Independent Ecology Institute, Plekhanov st., 40, 61001 Kharkiv, Ukraine
National Scientific Center “Institute of Experimental and Clinical Veterinary Medicine”, Pushkinska St., 83, Kharkiv 61023, Ukraine
email: anton.vlaschenko@gmail.com
Kseniia Kravchenko
Scientists at the Ukrainian Bat Rehabilitation Center, Ukrainian Independent Ecology Institute, Plekhanov st., 40, 61001 Kharkiv, Ukraine
Scientists at the University of Lausanne, Department of Ecology and Evolution, CH–1015 Lausanne, Switzerland
email: kseniia.a.kravchenko@gmail.com
Steven Seet / Jan Zwilling
Science communication at the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW), Alfred-Kowalke-Straße 17, 10315 Berlin, Germany
phone: +491778572673 / +49305168121
email: seet@izw-berlin.de / zwilling@izw-berlin.de
JOURNAL
Journal of Applied Animal Ethics Research
METHOD OF RESEARCH
Observational study
SUBJECT OF RESEARCH
Animals
ARTICLE TITLE
The War-Damaged Urban Environment Becomes Deadly Trap for Bats: Case from Kharkiv City (NE Ukraine) in 2022.