It’s getting crowded round here (Image: Subhoranjan Sen)

THE tigers in India’s Panna National Park will soon live in a forest that watches out for them. A wireless network of low-power radars is being developed to track everything that moves in or out of the forest. This helps keep the tigers safe from poachers, and villagers’ cattle safe from the big cats.

Built by Anish Arora at Ohio State University in Columbus, the work was originally designed as a way for the US government to monitor the flow of people across the country’s borders. Had the US border patrol not opted to build a 1100-kilometre-long fence instead, the system could have alerted officers to people trying to cross the border with Mexico anywhere other than at official points.

Arora’s system is the first wildlife-tracking technology that detects and reports on a specific animal in real time. It works by looking for the patterns created as radar reflects off different objects, and then comparing these to recorded signatures. When the system spots a human entering the tiger’s reserve, or a tiger leaving, it alerts the wardens.


When the system spots a human entering the tiger’s reserve, or a tiger leaving, it alerts the wardens

“It is as simple as that. The alarm goes off and poachers get caught,” says Arora. Or guards posted inside the 400-square-kilometre park can move to cut off a tiger that is advancing towards a farm. When the system is fully up and running, Arora says, it will cover all the most tiger-trafficked parts of the forest.

It’s not the only technology on the lookout in Panna. P. Vijay Kumar of the Indian Institute of Science in Bangalore is working on an infrared system that ignores swaying trees and shrubs, and sounds the alarm only when it detects an intruder. M. Radhakrishna at the Indian Institute of Information Technology in Allahabad is burying fibre-optic cables that detect slight changes of pressure at the surface. The step of a human or tiger makes the fibre bend slightly, changing the way light moves through it.

When it comes to imaging, Arora’s radar system has a big advantage over cameras. Gathering and processing radar data takes less computer power than visual images do, allowing the network to keep running day and night for long periods of time. “It can survive on very little power, a couple of AA batteries,” Arora says. He plans to put an updated version of the network live for several months starting in December (SenSys 2014, doi.org/w5b).

This article appeared in print under the headline “Radar network makes tigers good neighbours”