Thermal Imaging Advances Fight Against Poaching
Adam Yaney-Keller
Nearly 80% of the world’s remaining white and black rhinoceros’ populations are in South Africa, making the country both a sanctuary for rhinos and a target for poachers[1]. Nearly 1,000 rhinos were killed each year between 2013 and 2017, and although poaching has decreased since then, so has the overall population[1] [2] [3]. While many new technologies are being employed in the fight against poaching, the main line of defense remains foot and vehicle patrols [4]. However, these patrols can be dangerous, and even deadly for the rangers[4] [5]. A team of researchers, led by Professors Adam Hart and Anne Goodenough from the University of Gloucestershire in the UK, sought to determine whether Infrared Thermography or IRT, might be a useful tool for making these patrols safer and more effective.
IRT works by remotely sensing temperature, giving the user a visual of heat sources in their environment. “Think of it like a digital camera, but instead of detecting visible light the chip at the back detects infra-red given off by hot objects”, explains Hart. “It is basically a ‘heat photograph’”. Because of this, IRT can identify people hiding at night, when most poaching occurs. But how effective is it? And is it worth the price tag?
To answer these questions, the team tested a low-cost ($2,000 USD) and high-cost ($22,000 USD) handheld IRT unit versus the use of traditional high-powered flashlights for detecting hidden poachers in the bushveldt of Mankwe Wildlife Reserve in northwest South Africa. To do this, they set up a game of cat-and-mouse. “One of the co-authors, Rik Rolfe, was the ‘target’ – his job was to hide in the bush,” describes Hart. Observers then walked down a path trying to find Rolfe using each of the three technologies. When observers initially thought they saw the “poacher”, they stopped and informed one of the research team, who marked the location. They then continued down the path until they made a positive sighting, and Rolfe stood up to confirm if they were right. By doing this, they were able to measure the distance at which the patrolling “ranger” could first identify a hidden “poacher” and compare those distances, along with accuracy, between the different technologies.
Overall, they found that IRT was significantly better at detecting poachers from a distance, up to nearly 30 meters over the flashlight. They also found that the low cost IRT unit was just as effective as the high-cost one, which was nearly ten times the price and less user-friendly. “We thought the expensive unit we were using would be pretty good,” says Hart, “but we weren’t expecting the cheaper units to work just as well”.
The team published their results in the journal PLoS One in 2015, and have since begun leading anti-poaching workshops to teach about the tech’s advantages, and expanded the project into neighboring reserves in South Africa, Botswana and Namibia. “Staff using the [IRT] kit report feeling much safer as well as big reductions in poaching of all kinds”, reports Hart. In 2019 their efforts won them a Green Gown Award for sustainable research, highlighting IRT’s potential. And it’s not just Hart and team - FLIR Systems, Inc., which makes the IRT units used in the study, launched a $3 million initiative with World Wildlife Fund in 2019 to deploy IRT for anti-poaching in Kenya, which directly led to the arrest of 100 poachers [6] [7]. While Hart and others note that no single solution will stop the wave of poaching endangered rhinos and other species, IRT remains a promising tool in making the fight easier, and safer, for rangers and the wildlife they protect.
Images
View of poacher from 20 m hiding in the field study area : (a-b) illumination by an LED flashlight, what was visible to observers with the naked eye (poacher location is indicated with a white arrow); (c-d) images from low-cost IRT device (e-f) images from high-cost infrared IRT device [4].
If you would like to know more about the many ways thermal imaging can be used for wildlife, check out the BRAND NEW BOOK: Thermal Imaging for Wildlife Applications by Dr Kayleigh Fawcett Williams.
References
[1] Save the Rhino. “Poaching Numbers: Conservation: Save the Rhino International.” Save The Rhino, 2020, www.savetherhino.org/rhino-info/poaching-stats/.
[2] Mongabay. “Rhino Poaching in South Africa Declines for Fifth Straight Year.” Mongabay Environmental News, 7 Feb. 2020, https://news.mongabay.com/2020/02/rhino-poaching-in-south-africa-declines-for-fifth-straight-year/.
[3] Ferreira, Sam M., Bissett, Charlene, Cowell, Carly R., Gaylard, Angela, Greaver, Cathy, Hayes, Jessica, Hofmeyr, Markus, Moolman-van der Vyver, Lizette, & Zimmermann, David. (2017). The status of rhinoceroses in South African National Parks. Koedoe, 59(1), 1-11. https://dx.doi.org/10.4102/koedoe.v59i1.1392
[4] Hart, A. G., Rolfe, R. N., Dandy, S., Stubbs, H., MacTavish, D., MacTavish, L., & Goodenough, A. E. (2015). Can Handheld Thermal Imaging Technology Improve Detection of Poachers in African Bushveldt?. PloS one, 10(6), e0131584. https://doi.org/10.1371/journal.pone.0131584
[5] Winter, Stuart. “Battle against Poachers: 740 Rangers Have Been Killed Protecting ]\\Elephants and Rhinos.” Express.co.uk, Express.co.uk, 31 July 2017, www.express.co.uk/news/nature/835165/battle-poachers-rangers-killed-protecting-animals.
[6] FLIR, Inc. “FLIR and World Wildlife Fund Announce Effort to Combat Rhino Poaching in Kenya.” FLIR Systems, 8 Jan. 2019, www.flir.com/news-center/press-releases/flir-and-world-wildlife-fund-announce-effort-to-combat-rhino-poaching-in-kenya/.
[7] Palminteri, Sue. “'Better and Better': Thermal Cameras Turn up the Heat on Poachers.” Mongabay Environmental News, 22 Nov. 2019, https://news.mongabay.com/2018/07/better-and-better-thermal-cameras-turn-up-the-heat-on-poachers/.
