Christopher Nolan’s Dark Knight patrols an inhospitable city and faces a daily struggle of survival just like the bats of the Western Ghats of India. These bats are also fighting for their lives against their loss of habitat to tea and other crop plantations. The Western Ghats is the most densely populated of the 35 biodiversity hotspots in the world. It’s little surprise that just six percent of the land has vegetation untouched by humans. The native forest now exists as fragments, which has devastated animal populations, bats included. The presence of humans in the area cannot be denied or easily reversed, so strategies to continue the human use of the land while improving the habitat for animals is essential to our coexistence.
Luckily, Claire Wordley and her colleagues at the University of Leeds in the United Kingdom recently published a journal article in Biological Conservation about bat habitat fragmentation. They researched how a variety of species of bats handle changes in land use. The team looked at populations of bats in areas of different land composition to determine which factors contribute to better habitats.
It turns out that tea plantations that heavily modified the land were not very hospitable to bats, however, land that is dominated with tea crop that also contains forest fragments could house several species of bats. Coffee grown in the shade of the existing forest also provided good habitat. Basically, the more scattered forest an area has, the more likely that area can support bat populations. This makes sense since the bats’ native habitat is forest. It’s just a good thing they can still survive with the tea and coffee crop dominating their home.
The researchers found that the individual bat species’ niches were generally broad, which is very helpful when the habitat is narrow. Small scale (100-500m) variability in habitat can still effect the populations, probably because bats can exploit small or even isolated foraging areas. This opens up a lot of viable land use strategies to conserve bats. The most obvious method consists of avoiding covering entire landscapes with tea crop. Perhaps coffee could be a bigger focus instead of tea. Leaving some forest corridors between their habitats would also be helpful.
Some people, for the sake of their economic interests, may disagree with altering our commercial crop systems. However, the bats and other animals and plants in the forest fragments are an essential part of the local ecosystems. Forests animals can provide human and ecosystem benefits like pollination and pest control, which offset the economic costs of conservation.
Habitat fragmentation is a serious issue in the Western Ghats and everywhere else. “Nearly 20 percent of the world’s remaining forest is the distance of a football field — or about 100 meters — away from a forest edge. Seventy percent of forest lands are within a half-mile of a forest edge. That means almost no forest can really be considered wilderness,” said Dr. Nick Haddad, William Neal Reynolds Distinguished Professor of Biological Sciences at North Carolina State, in a recent NC State News press release.
While the statistic is sad, human activity is inevitable, and with the exponential human population growth trend, our natural resource exploitation is fated to worsen. The best strategies will come from our creativity to use resources so that land is still suitable for other animals as well. A clear example is given by how we can fragment our own tea plantations and plant more coffee to allow bats to inhabit the scatter of forest that’s left. It’s not only the changes that they deserve, but also the ones that they need right now.
Wordley, C., Sankaran, M., Mudappa, D., & Altringham, J. (n.d.). Landscape scale habitat suitability modelling of bats in the Western Ghats of India: Bats like something in their tea. Biological Conservation, 529-536.