Unlike fictional Gotham City’s Batman and Batgirl, this crew of researchers – some of whom describe themselves as “Batmen” – did not band up to deal out their brand of vigilante justice.
Exploring their way through Meghalaya’s karst caves – some of the longest in the world – cave biologists (speleologists) and bat experts from India and abroad ended up cataloguing the astounding diversity of the flying mammals in the state that harbours half of the recorded bat species in the country.
A longing to explore new caves and the thirst to understand bats brought Zoological Survey of India scientist Uttam Saikia, Meghalaya researcher Adora Thabah and international cave biologists together as part of the multi-country ‘Caving in the Abode of the Clouds’ project that aims to discover and describe the caves in the state in northeast India.
During their adventures in partnership with Meghalaya Adventurers Association, the researchers also stumbled upon new species in the grottos as also hitherto unknown roosting sites of extremely rare bats. Their explorations also led to a village council dedicating a forest patch to conserve an elusive species.
The subsequent inventory discussed in the book chapter, “The Bat Fauna of Meghalaya, Northeast India: Diversity and Conservation”, not only discusses the impressive diversity (65 species), their distribution but also spotlights the conservation challenges, including indiscriminate mining, faced by the less studied mammals.
“Since bats are one of the less studied mammalian groups, comprehensive diversity and distribution information is not available for most of the Indian states which effectively hampers formulating any conservation efforts,” Saikia said.
The catalogue is rooted in published results, online collection database of museums abroad (especially that of Field Museum of Natural History, Chicago, which houses a considerable collection of bat specimens from Meghalaya) and supplemented by recent field surveys in the state (2011–2018) and examination of voucher collections deposited at Zoological Survey of India, Shillong (ZSIS).
“A faunal inventory is the starting point of any conservation efforts. It also helps in prioritising conservation action by directing required attention to the threatened species,” Saikia said.
As many as 65 species of bats are recorded from Meghalaya so far and this number is also likely to increase to some extent with more attention and investigations. Considered as the wettest place on earth, cloud-cloaked Meghalaya is abundant in limestone and coal deposits strewn across three hill regions namely Khasi Hills, Jaintia Hills and Garo Hills.
Discovering bats in the caves of Meghalaya
The rain, warm climate and extensive areas of limestone, particularly in the southern fringe of the Meghalaya plateau, has provided the perfect mix to created many fine caves, of which at least 1,500 caves have been identified, 970 of them explored and surveyed in excess of 427 kilometres underground.
These natural systems of caves, caverns and passages provide ideal roosting habitat for a large number of bat species and for this reason the state of Meghalaya harbours a wide range of bat species, noted Saikia. Though they are adapted to a wide variety of habitats in the state, majority seek the shelter of the caves.
“Bats are known from most of the caves in Meghalaya and some caves harbour dense bat colonies containing thousands of individuals and also a number of poorly known species,” the book chapter notes.
“Compared to other states of Northeast India, the bat fauna of Meghalaya is rela- tively better known. This is primarily because of the fact that the provincial British administration was based at Shillong, the headquarters of erstwhile Assam Province and naturalists under the patronage of the British government conducted extensive faunal surveys in the Khasi and Jaintia Hills area,” the chapter said.
Some of recently added species are the greater bamboo bat (Tylonycteris robustula), Kelaart’s Pipistrelle (Pipistrellus ceylonicus), Miniopterus pusillus, northern tailless fruit bat (Megaerops niphanae) and Tylonycteris malayana.
The inventory also lists new roosting sites of the extremely rare and elusive Wroughton’s free-tailed bats (Otomops wroughtoni) in the Jaintia Hills in southeastern Meghalaya. Up until the reported discovery of the three new roosts in Jaintia Hills in 2014, the species was “known so far by a single breeding colony in Karnataka in southwestern India and two single individuals recorded in Meghalaya and Cambodia.”
The addition (of at least 97 individuals confirmed in the Meghalaya roosts) doubles the known world population of the Wroughton’s free-tailed bats to 200 individuals.
Swiss bat biologist Manuel Ruedi, who first participated in the project in 2011 following an invitation from the project’s co-leader Thomas Arbenz, recalled the “amazing” but “underexplored” biodiversity jewels of Meghalaya and how the caving project worked with local tribal community members to get the job done.
“I only had to come along with my camping gear, pitch my small tent and then do my job as a batman,” said Ruedi alluding to the partnership.
“The results were amazing with many species recorded for the first time in the region, and even for India, underlining the fact that the biodiversity jewels of Meghalaya were clearly underexplored … and even the discovery of two new species of bats, one dedicated to the Jaintias and called Murina jaintiana,” said Ruedi, curator of the mammal collection in the Natural History Museum of Geneva, Switzerland.
But all is not well for the bats of Meghalaya.
Mining, hunting and human disturbances threaten bat population
The caves are mostly located in coal or limestone belts and disturbances to roosting sites through rampant mining, human presence and hunting have caused danger to the nocturnal animals, said Saikia.
“Mining practices in the state is indiscriminate and unscientific and is also ecologically very damaging. Mining has caused extensive ecological damage in the Jaintia and Garo Hills region including deforestation and pollution which is directly affecting bat populations,” he said.
Bats are also prized on the menu. Hunting bats for bushmeat is a fairly common practice in the Jaintia Hills which has certainly caused decline of populations, maintains Saikia.
“There is no study/quantitative data to highlight the role of hunting in bat population decline. However, from my observations during the last few years, it it certainly a major threat,” he said.
Meghalaya State Biodiversity Strategy and Action Plan (draft) mentions “the superstitions associated with bat meat consumption are a major threat to the species of bats in Meghalaya”.
There still a lot to discover and given the pace at which the natural habitats are being destroyed (both due to agriculture need or to mining activities), it is now absolutely urgent to document this biodiversity before everything disappears, believes Ruedi.
“Not only bats use the cave systems to roost and the surrounding habitats to find their food (insects), but a number of other creatures need this environment, so they need to be protected to continue their role in the natural systems,” Ruedi said.
Meghalaya village protects a rare bat
The field surveys dovetailed with communication efforts eventually encouraged a village in East Jaintia Hill district in the eastern most part of Meghalaya to dedicate a small patch of their forest to save the rare Wroughton’s free-tailed bats.
“We also, together with locals, taught to the villagers what is the role of bats in their environment, and how important they are to help control pest insects and also that they should not only be viewed as potential proteins to eat, but also a creatures of God worth protecting. In particular, we gave an illustrated talk (with my pictures, taken during the field work) in the village adjacent to a large cave harbouring a large colony of very rare bats to encourage those villagers to protect their cave, habitat and inhabitants,” recalled Ruedi.
The village in question is Pynurkba.
“The area where the cave is located is in a forested patch that is looked after by the community. We came to know about the discovery of the free-tailed bats through the researchers. It took us almost one year to convince the village elders to declare the area as a community reserve. It is a 2.4 hectares patch and surrounds the cave,” added H Lato, divisional forest officer of Jaintia Hills.
Saikia said the then chief wildlife warden BS Kharmawphlang showed a keen interest for declaring this area as community reserve and also for conservation of bats as a whole. K Mukhim of Lady Keane College of Shillong also was instrumental in convincing the villagers in the initial stage, he said.
“We are now in the process of notification,” said Lato.
(The article first appeared in Mongabay-India)