Volume 40
Issue 2

Racing to discover the secret life of one of the world’s most endangered bats

by Christie Wilcox

Only an estimated 1,200 to 1,300 Livingstone’s Flying Foxes exist on the planet, and they live on just two of the Comoros Islands, which are located near Madagascar. These curious-looking, fluffy, fruit-eating bats live in high elevation areas on the islands, and Dr. Isabella Mandl spends her time studying them.

Livingstone’s Flying Fox.

Dr. Mandl is a Wildlife Biologist with the Comoros-based NGO Dahari, and she implements research and management programs for the flora and fauna of the Comoros. One of her projects was a monitoring effort for these Critically Endangered endemic flying foxes—a task that sounds much easier than it really is.

Livingstone’s Flying Foxes weigh up to 2.2 pounds with a wingspan of nearly 5 feet, so they’re not the easiest animals to handle, and getting to them is difficult. They live at more than 1,900 feet in elevation, and the terrain is brutal. The roost Dr. Mandl visits most often requires hiking an hour and a half up a steep slope and crossing a river. “It requires endurance to get there,” she says. “You just have to know you’re going to see something cool at the end.”

But perhaps the larger problem is there is next to nothing known about the animals themselves. Outside of a few established roosts, where they spend their time is a mystery. Even their diet is unknown—all researchers have are educated guesses as to which fruits they consume and where. “We don’t know about whether these feeding sites are located within forests, for example, or if they’re located in agricultural areas—and that kind of information would help us make conservation management decisions,” Dr. Mandl says.

Learning the Livingstone’s Secrets

It was incredibly important to determine the bats’ preferred habitats and needs, so the Dahari Ecological Research Team and the University of Comoros launched a GPS tracking study to get that critical intel. The idea was to catch bats and outfit them with GPS collars that track their movements for a period of time before the tags fell off. But the bats didn’t cooperate. “They see the net you put up,” Dr. Mandl explains, noting they often dodge it.

In fact, they’re so evasive that when Dr. Jon Flanders, Bat Conservation International’s Director of Endangered Species Interventions, went to the islands to help with the fieldwork, he didn’t end up collaring a single bat. “I have this great video of this bat flying around, seeing the net, and just flying over it,” he says, smiling.

Livingstone’s Flying Foxes have a 5-foot wingspan.

If they do end up being captured, some bats don’t always cooperate. One individual removed his collar after a mere four weeks, when the collars would normally fall off after a few months.

Still, those four weeks of data, combined with 10 months from a female bat, were priceless to the researchers.

“We figured out that they’re very mobile,” Dr. Mandl says. The animals switch roost sites more often than the team expected. Not only did the collars reveal the location of the roosts, but they also suggested likely feeding areas.

One of those came as a surprise, as it was located on agricultural lands.

“These results provide us with vital information to help save these bats from extinction,” Dr. Flanders says. “The GPS data generated from these two bats is a testament to how advancing technology can advance conservation work.”

Next, Dr. Mandl would like to figure out exactly what Livingstone’s Flying Foxes are eating, and if they’re acting as seed dispersers or pollinators for native plants. Very little undisturbed forest is left in the Comoros, so these bats could be playing essential roles in maintaining the islands’ biodiversity. “[It] would be really good to find out, because then they could actually help conserve the landscape,” Dr. Mandl says.

Such information could also help convince locals that the bats and their homes are worth protecting. Unlike some fruit bats, the Livingstone’s Flying Foxes aren’t hunted or seen as a nuisance, but they’re still threatened by habitat loss, especially the loss of the large, old trees they roost in. By working with the local community, Dahari is helping make the bats part of a broad, sustainable conservation solution for the area.

In the process, Dr. Mandl hopes to learn as much as she can about these bats, and quickly. While their numbers seem to be somewhat stable, with such a small range, there’s always the chance that a natural disaster or unforeseen event could tip the scales against them, causing these charismatic critters to be gone for good.

Bat stats

Scientific name: Pteropus livingstonii

Family: Pteropodidae

Colony size: 5–150

Weight: Up to 1,000 grams

Diet: Frugivorous

Status: Critically Endangered

Region: Comoros Islands