Bat-ventures: expedition into Tsingy de Namoroka National Park
By Giorgia Castiello, Student Researcher, Namoroka Site
On my first expedition into Namoroka National Park, I was immediately struck by the intense heat—a fitting start for my pilot research project. I am conducting my PhD in Evolutionary Biology at La Sapienza University in Rome, focusing on the impact of forest structure and human activities on bat communities. Working with Wildlife Madagascar, I arrived with my team in the small village of Namoroka, the namesake for the adjacent protected area, and despite being early, everyone was waiting for us. The village leader greeted us and took us to the Ampanjaca, a wise man who could “see.” It was in his hut that I took part in the Joro, the first animist ceremony of my life. The man asked the forest spirits to protect our expedition, but on one condition: we had to respect the sacredness of nature and not take anything away from it. Following the ceremony, we departed for the forest, with several local villagers helping to port our equipment. We hiked for about an hour and a half, occasionally fording rivers barefoot and taking a respite from the sun under giant mango trees, before we finally arrived at our campsite.
Joined by Caren and Lomeris, I couldn’t have asked for a better team to help me carry out this difficult work! Our work began in the late afternoon at 5:00 p.m. as we headed to the caves to start our exploration. Some of the caves we explored were nestled deep in the forest, with larger chambers where tree roots dangled from the ceiling, creating a fascinating blend of forest and subterranean worlds. Others, especially those more characteristic of the tsingy (limestone karst) landscape, had much narrower entrances and formed true labyrinths inside, with winding passages that required careful movements. Exploring each cave took a long time, as we moved slowly and methodically in search of bat roosts, all while taking careful precautions to not disturb any bats or the other cave inhabitants. The incredible variety of cave structures made each exploration unique, adding to the experience of working in this extraordinary environment!
Once we located a roost, our work began! We set up our harp trap and waited until dusk for the bats to emerge from the cave. The harp trap is specially designed for effectively and safely catching bats, with a structure similar to a harp. Unable to detect the fine wires, the bats end up flying into them and gently falling into a soft bag below. Truly ingenious, isn’t it? With this portable structure, we were able to catch many bats.
For me, the most exciting moments were always in the darkness. Every time we heard a bat drop into the bag, we would collectively wonder: “What species is it?”
Naturally, like humans, bats have distinct personalities. Some individuals are calm, while others are…let’s say more than a bit restless! Lomeris usually took charge of the more unruly ones, a sight that Caren and I always found amusing.
Left: Caren weighing a bat in a bag while Lomeris identifies another bat. Right: Giorgia inspects one of the bats collected in the harp trap.
Once all of the bats collected with the harp trap were safely secured, we returned to the camp to begin collecting morphometric measurements. This process involved capturing detailed data on each bat, including forearm length and shape, body mass, and other relevant anatomical characteristics. We also recorded the echolocation calls of each species. Indeed, the purpose of my research is to create an acoustic library of Malagasy bat species found in Tsingy de Namoroka National Park. This library is intended to be a valuable resource for future conservation-focused studies, to support long-term monitoring of species populations and to promote greater knowledge of these species. This work represents a pilot study, and I will need to return for further research, although the sampling we have completed so far has already yielded promising results. Though the data collection often took several hours, we always prioritized the welfare of each bat, and all individuals were carefully released before dawn at the exact spot where they were collected.
After sunrise, we finally had a chance to rest, although this was not always possible. The lively chorus of the night creatures, especially the energetic fork-marked lemurs, often made it difficult to fall asleep, reminding us of the extraordinary biodiversity surrounding us. In addition to the lemurs, we would hear the calls of various nocturnal birds, whose haunting melodies filled the night air. In Namoroka, each night presented a fascinating soundscape!
Working with bats, though demanding, is truly unique. It requires adjusting to a reversed schedule—active at night, resting by day—but it brings incredible rewards. I believe the forest at night holds a special magic, and it is a privilege to witness the sunset and sunrise at Namoroka, surrounded by species found nowhere else on Earth. Being here, sharing the hidden world of these extraordinary creatures, reminds me how rich and unique Madagascar’s biodiversity is, a treasure that deserves to be widely known and protected. I am truly grateful to Wildlife Madagascar for this opportunity, and I can’t wait to return to continue my research and play a role in conserving these remarkable species.
