A multi-national team of experts led by Bat Conservation International (BCI), Rwanda Development Board (RDB), and the Rwanda Wildlife Conservation Association (RWCA) has rediscovered Hill's horseshoe bat (Rhinolophus hilli), a critically endangered ‘lost bat species’ not seen in forty years. To support wider efforts to understand and protect imperiled bats, BCI has published records of the rediscovery in their first dataset shared openly through the Global Biodiversity Information Facility (GBIF).
“Going into this project we feared the species may have already gone extinct. Rediscovering Hill’s horseshoe bat was incredible – it’s astonishing to think that we’re the first people to see this bat in so long”, said Dr. Jon Flanders, BCI’s Director of Endangered Species Interventions. “Now our real work begins to figure out how to protect this species long into the future.”
After 40 years, the Hill’s horseshoe bat has been rediscovered by a team of conservationists. Photo by Jon Flanders, Bat Conservation International.
The Rediscovery of Hill’s Horseshoe Bat
The horseshoe bat rediscovery marked the culmination of survey efforts that started in 2013, as the team’s dedication paid off during a ten-day and night expedition to Africa’s Nyungwe National Park in January 2019. Dr. Winifred Frick, BCI’s Chief Scientist, recalled, “We knew immediately that the bat we had captured was unusual and remarkable. The facial features were exaggerated to the point of comical. Horseshoe bats are easily distinguishable from other bats by characteristic horseshoe shape and specialized skin flaps on their noses”.
Careful measurements of the bat before they released it back into the wild were an early tip-off that this could be the lost species they came to find. Dr. Flanders then traveled to visit museum archives in Europe to compare the only known specimens to verify that what they had captured in the African forest was, in fact, the first evidence in 40 years that Hill’s horseshoe bat still exists. Catching this elusive species also allowed the team to collect additional information to ensure it is easier to find in the future – including recording the first-ever echolocation calls that Hill’s horseshoe bat emits as it hunts for insects.
Bat Conservation International (BCI) and collaborators collect data on several bat species within the Rwandan national park. Photo by Jon Flanders, Bat Conservation International.
“Knowing the echolocation calls for this species is a game changer," said Dr. Paul Webala, Senior Lecturer at Maasai Mara University, and one of the team’s lead scientists. Since catching the pair of Hill’s horseshoe bats, the Nyungwe Park Rangers have been setting out detectors that ‘eavesdrop’ on the bats during their nightly flights through the forest.
The rangers conducted audio surveys with Wildlife Acoustics bat detectors in 23 locations over nine months resulting in recording a quarter-million sound files. Analysis of the sound files revealed Hill’s horseshoe bats were heard at eight locations, all within a small area. “All the work so far confirms that this is a very rare species with a very small core range. We look forward to collaborating with the Rwanda Development Board and Nyungwe Management Company to strengthen the existing conservation efforts to ensure it stays protected,” said Dr. Frick.
Careful planning and strong partnership support between all the agencies, organizations and experts involved in this initiative were key to its success, according to Dr. Olivier Nsengimana, founder and executive director of the Rwanda Wildlife Conservation Association.
Protecting African Bat Diversity
Records from the 2019 survey and the rest of the nine-year project’s fieldwork in Africa are included in a dataset openly available through GBIF. Other notable highlights include the first record of Lander's horseshoe bat (Rhinolophus landeri) in Nyungwe and the first known occurrences of the Damara woolly bat (Kerivoula argentata) in Rwanda. The research team has released the dataset alongside a preprint describing the findings and survey methods currently in review with Biodiversity Data Journal. Sharing such data, even for such a rare species, allows the international scientific community to put it to use immediately and aid conservation and research aimed at documenting and protecting African bat diversity.
“Nyungwe National Park is one of the most biologically important montane rainforests in Central Africa, supporting an exceptional range of biodiversity including many rare and endemic species, including bats,” said Mr. Eugene Mutangana, the Conservation Management Expert, Rwanda Development Board. “These findings reinforce the importance of Rwanda’s committed stewardship of Nyungwe National Park as a global biodiversity hotspot and our conservation efforts, including implementing species management actions. We look forward to continuing this collaboration with BCI, RWCA, and the rest of our partners to find out more about the bat diversity in this incredible landscape”.
“Sharing the survey data to be accessible freely through GBIF is as important to bat conservation as the actual findings,” said Dr. Frick. “These data belong to anyone and everyone working to ensure these species have protected forests to call home. Open data sharing ensures we live up to the promise that conservation benefits us all.”