A study on the firefly species and their habitats in the Anamalai Tiger Reserve (ATR), where mega congregation of the insects and their synchronised bioluminescence is observed during summer every year, has underscored the need to take proactive conservation measures to preserve their habitat and safeguard the ecosystem.
It has also stressed the need to minimise the impact of artificial light on the communication and mating behaviours of fireflies.
Extensive field surveys were conducted during the firefly mating seasons from 2022-2023 in the ATR for the study, which was authored by Sriram Murali and Mathi Thumilan B. of Wild and Dark Earth — a non-governmental organisation engaged in the study and conservation of nocturnal habitats; Geetha G. Thimmegowda of Nithyaharidhvarna Foundation; and S. Ramasubramanian, M.G. Ganesan, K. Bhargava Teja and V. Selvam, officers of the Tamil Nadu Forest Department.
The study, published in the Indian Entomologist recently, was aimed at understanding the ecological significance of synchronous fireflies and the diversity of the species in the ATR. The researchers recorded the flashing patterns of fireflies (whether ascending or descending) in individual trees and the timing of flashing events, among others, for an analysis of the synchronisation phenomenon.
They also observed mating behaviours such as rapid pulsations and the duration of flashing sequences.
Three species of fireflies — Asymmetrica humeralis, Abscondita genus (species unknown) and Curtos sp — were identified from the ATR. They exhibited variation in size morphology, but shared similar types of habitat with overlapping zones.
As per the study, the synchronised flashing behaviour of fireflies serves as a vital ecological marker, reflecting the health of their habitat and the surrounding environment. Understanding their behaviour and the factors influencing flashing patterns can provide insights into the overall health and functioning of the ecosystem and interactions with other species in the food chain.
According to the authors, the well-preserved core zone of the ATR serves as a critical sanctuary for firefly activity, especially during the crucial breeding season in April and May.
It is vital to maintain the area undisturbed to safeguard their eggs and larvae from potential harm due to soil unrest or the introduction of foreign elements, they said.
As fireflies rely on bioluminescence for communication and mating, artificial lights in the buffer zone of the reserve may disrupt their delicate synchronisation and mating behaviour.
Hence, it is crucial to establish a sustainable tourism model in the buffer area to minimise light pollution for preserving the firefly population, says the study.
The authors feel that the introduction of lighting within the reserve should be carefully considered. Use of low luminosity torch lights by field staff during patrolling, limiting vehicular movement at night, regulation of religious festivities that coincide with the peak mating season of fireflies at Kozhikamuthi tribal settlement, designating a watcher to monitor the firefly population, preventing illegal activities and raising awareness about light pollution are some of the measures suggested to preserve the firefly habitat.
