Blinking solar-powered lights have come up along the nylon nets bordering the forests in the Sunderbans in a bid to prevent tiger intrusions into villages.
Wild animals, especially nocturnal ones like tigers, usually keep off lights, said foresters. A wildlife expert said intelligent animals might get habituated to static lights after a while. But blinking lights create a sense of uncertainty in them.
Forest officials are hoping the lights provide an additional layer of deterrence, especially in areas where the nets are damaged.
The pilot project started in the middle of December in a phased manner and has since covered two pockets in the South 24-Parganas forest division. The villages on the other side of these forest compartments have in the recent past witnessed tiger-straying incidents.
In total, the forest department has installed 80-odd lights along the nets bordering the Dhanchi II and IV and the Ajmalmari I and II forest compartments.
“The lights have been installed on top of poles that hold the nylon nets together and on trees dotting the fence. They are charged during the day. After sundown, they start blinking,” said Milan Mandal, the divisional forest officer of South 24-Parganas.
“It is still too early to say anything on the efficacy of the lights. But our men patrolling the areas would see pugmarks near the fence on a regular basis before the lights came up. Now, pugmarks are spotted rarely,” said Mandal.
A creek that meets the Thakuran river separates Sridharnagar village from the Dhanchi II compartment. On the other side of Dhanchi IV is a village called Sitarampur. Makri, a river that is connected to the much bigger Matla, separates the Ajmalmari forest compartments from neighbourhoods like Bhubaneswari, Debipur, Deulbari and Gurguria.
In the second week of December, a tiger had strayed near Bhubaneswari village in the Kultali block. It was driven back to the Ajmalmari forest in an operation that lasted close to 48 hours.
“The lights in the Ajmalmari forest came up after that. All the areas where the lights have been installed are prone to human-wildlife conflicts,” said Mandal.
Nylon nets, which border around 175km of forests in the Sunderbans, have proved very useful in mitigating human-wildlife conflict. But there are challenges.
Humans breach the nylon nets in these areas to enter the forests on the sly to catch fish and crabs. Tigers also stray into human habitats through these breached nets.
The unique terrain of the Sunderbans, the world’s only mangrove delta that is home to tigers, is also a big challenge. The tidal flow of water leaves the net fencing vulnerable.
“Especially in narrow openings to creeks, it is impossible to have a foolproof fence. The incursion and recession of water weakens the base of the poles that support thenylon nets. As the poles become wobbly, the nets areeasier to breach. Tigers cross over through the mudflats during low tide,” said a forest official.
A retired forest official who spent several years in the Sunderbans welcomed the initiative, but said “the real test would be during next winter, when most incidents of straying happen”.
Abhishek Ghoshal, head of the human-wildlife conflict mitigation division of the Wildlife Trust of India, a nature-conservation organisation, said time will prove the efficacy of the solar lights.
“Intelligent animals might get habituated to static lights. But blinking lights create a sense of uncertainty in them,” he said.
The agency had in 2019 installed a series of solar lights in a pocket of Purba Gurguria, on the other side of the Ajmalmari forest, following a series of conflicts.
“We set up 50 streetlights along a 1km stretch. The lights have been very useful in preventing straying incidents on that stretch,” said Ghoshal.
Another veteran forester said the department should also focus on periodic checks of the lights to prevent theft and damage.
“Since solar lights are cheap and effective, some might want to steal them. People entering forests illegally might also want to damage them to avoid detection,”he said.