Unexpected elephant raids are the worst nightmare of a forest-fringe village in India. But what if there is somebody to text you in advance that the jumbos are on the way? Researchers in Tamil Nadu claimed to have developed an intrusion detection system which can text forest officials an early warning if an elephant heard is moving towards a village.
|An Indian elephant in the wild: from Nagarhole National Park in Karnataka|
Texting an elephant raid warning
According to S. J. Sugumar of Coimbatore Institute of Technology and R. Jayaparvathy of SSN College of Engineering Chennai, who developed the system, it functions by tracking the movement of the elephants electronically with the help of the vibrations on the ground created by the footfall of the animal. The system, according to the researchers, has to be implemented in “specific pockets identified based on the analytical results along the forest border areas where the elephants can intrude from the forest into human habitation.” It consists of a geophone string, threshold comparator with amplification module, embedded micro controller, GSM, and the power supply.
A research article published in Current Science journal about the system says that the footfall of the elephant produces a vibration in the ground which is sensed by the geophones that are buried underground. After sensing the vibration, the geophone will generate an electrical signal which will be amplified and compared with a set threshold value which is based on that generated by the footfall of a single elephant. If it exceeds the threshold, the system is designed to trigger the embedded controller to send a warning SMS with the help of the GSM transceiver to the forest officials. The geophones with a range of 120 square meters can cover a large area when used as a string of five geophones, claim the researchers.
Impact on human-elephant conflicts
|Geo-phone as part of the elephant intrusion detection system|
(Image Courtesy: Current Science)
The study was carried out in Coimbatore forest division which has recorded a number of cases of human-elephant conflict. According to official figures, there were 680 incidents of elephant intrusion into human habitat in 2011 while it was 844 in 2010 and 560 in 2009. In 2011, 14 people were killed in elephant attack while the figure was 16 in 2010 and 11 in 2009. In the conflict, there was a reported death of 10 elephants in 2011, 11 in 2010 and 12 in 2009. The implementation of the system is expected to help bring down the number of incidents of unexpected elephant raids and resulting causalities on both sides.
However, there are chances that other heavy animals walking over the buried geophones trigger false alarms. To avoid this confusion, the researchers have identified four different types of possible responses and have designed the system in such a way that false alarms are not triggered. According to the researchers, on field trials, the performance of the system to differentiate the vibrations generated by different species of animals was 91.25 percent. Analyzing the migration data of elephants in an area can be well used to predict the possibilities of intrusion almost precisely, say the researchers.