One of the rarest bats in Bulgaria, Geoffroy’s bat (Myotis emarginatus) roosts mostly in caves and old mines. That may be its undoing, as disturbances by cave explorers seem to be the major threat to the nation’s few Geoffroy’s nursery colonies.
Rumyana Panduraska-Whitcher of the Bulgarian Institute of Zoology, with a grant from BCI’s Global Grassroots Conservation Fund, is beginning to remove that threat.
All of Bulgaria’s 29 insect-eating bat species are protected by law, but Geoffroy’s bat needs special attention because of the vulnerability of its roosts.
The researchers, led by Panduraska-Whitcher, studied 10 nursery colonies, monitoring temperatures and other cave conditions, as well as the bats’ population and reproductive status. The study found that colonies in caves visited by humans often declined, while those spared such disturbance remained constant or increased their numbers in the past 10 years.
With these data in hand, the team proposed federal protection for Kozarnika Cave, which houses approximately 150 of the threatened bats. The Ministry of Environment says it will declare the cave and its surroundings a protected site and national monument.
The team also proposed that regional authorities protect the entrances to other caves and bunkers used by Geoffroy’s bats. Signs were posted at seven important roosts to restrict visits while the bats are giving birth and raising their pups.
The team produced 1,500 Geoffroy’s bat posters for distribution to schools, cavers’ clubs, tourism groups, and others.