Jungle Book: What caused the fireflies to fly away?

Pretty bungalows with gardens tucked away on sleepy streets, stars shining in the night sky and the sound of insects greeting you outdoors late in the night:  All of this seems so much in the distant past now that it has become even hard to imagine in a city that bears little resemblance today to what it used to be just a few decades ago.

Catching fireflies on moonlit nights in the backyards of homes was quite usual too in the Garden City with its many parks and tree- lined avenues. But almost unnoticed by most, these little insects with the strange ability to produce light have almost vanished in a fast concretising Bengaluru, that has little space left today for nature to thrive.

“Fireflies belong to the Lampyridae family of insects in the beetle order. They are an under- explored group of insects here as not much research  has been done on them in this country,” says Mr Priyadarsanan Dharma Rajan, a senior fellow, working in the field of insect taxonomy, ecology and conservation, at ATREE,who believes fireflies are declining in  population  in the city due to light pollution. “Fireflies produce light to communicate with each other and to find a mate. This communication is being hindered by the light pollution we are causing,” he explained.

The other reason why they are no longer flittering  around in numbers like before and illuminating dark nights is because their natural habitat has been taken over by buildings and roads in the city, he adds. “Fireflies, when very young, grow under the soil as they are largely carnivorous. They produce light when they are fully grown for many reasons, but especially to attract mates. But with the urban sprawl we are losing their habitat. Until recently we saw a good population of fireflies in  green spaces of educational institutes like the Indian Institute of Science and many more, but now these institutes too are getting cramped with more buildings in their grounds,” Mr Rajan regretted, emphasising that fireflies could be conserved and studied in an urban ecosystem now only if large campuses of universities or other organizations made an effort to have sprawling green spaces in their midst.

If fireflies are no longer found as commonly in the city as before, they are thankfully still found in plenty in the protected areas of the state like the Nagarhole sanctuary where Mr Rajan and other researchers  stumbled upon a cluster of them flashing their light in a strange synchronised fashion, forming an illuminated wave in the dark of the night. “ It was as if there was electrical illumination in the forest. We are still not sure  how they managed to  flash their light in such a synchronised pattern,” he said.

Researchers from Malaysia and other South Asian countries are currently trying to solve the mystery of the synchronised flashing of lights by fireflies in the tropics.

The phenomenon of fireflies, also called glow worms or lighting bugs, and other insect species producing their own light is called bioluminescence. A combined study by seven scientists from the Connecticut College, Hauptman-Woodward Institute, University of Buffalo and Yale University in the United States, which has been published in the Journal of the American Chemical Society,  provides a detailed explanation about bioluminescence. While research continues elsewhere into the fireflies and their strange light-giving property, scientists here continue to  worry about bioluminescence species possibly going extinct in Bengaluru.

Warning that this is by no means a far-fetched possibility, they emphasise that everyone has a  role to play in protecting such species by reducing light pollution and creating more ecosystems for them to thrive in, if only to let their  children and grandchildren continue to enjoy seeing them light up the night.