Who flees from cat growls in the dark? Asian elephants.

Playbacks of predator growls can be a tool to deter elephants and reduce human-elephant conflicts. Wild Asian elephants startled and eventually retreated upon hearing playbacks of leopard and tiger growls. Elephants vocalized loudly to leopard growls but remained silent to those of tiger, corresponding to the different threat levels posed by the felids. The setup can be improved to reinforce elephant response.

Over two decades ago, an Indian horticulturist showed his four-year old son an Asian elephant. That encounter kindled a life-long fascination with the gentle giants in young Vivek Thuppil. “Ever since I was young, elephants have been my favourite animal,” recalls Vivek, now a freshly minted animal behavior Ph.D. graduate from University of California-Davis. “I could spend hours and hours watching them.”

Male Asian elephant in India. By Yathin S Krishnappa, 2005.

Male Asian elephant in India. (credit: Yathin S Krishnappa)

Sadly, human encounters with elephants can be ugly, even lethal. Surveying news of human-elephant conflicts during 2003-2009, a study counted reports of 226 human and 87 elephant deaths in Asia; India alone suffered half of these casualties1. Actual losses could be higher. Another study reported that human-elephant conflicts in India killed over 200 elephants during 2006-2011 and 400 people in 20102. Elephants were, and are still electrocuted or poisoned as retribution for the trampled houses, crops and human lives. Although estimates vary, one thing is certain: in India, human-elephant conflicts are not abating.

India’s troubles with human-elephant conflicts are not surprising. Of the 40,000 wild Asian elephants in the world, more than half of them roam India. India is also home to 1.2 billion people, many who are farmers. Such high densities of overlapping human and elephant populations spark frequent encroachment of habitats, often ending in violence.

“Crop-raiding by elephants (in India) is very common,” Vivek explained. “More elephants are killed as a result of agriculture conflict than other sources.”

In contrast, Malaysians and our estimated 3000 wild Asian elephants share a less tumultuous coexistence. Although the Malaysian Department of Wildlife and National Park received about 800 complaints of human-elephant conflicts yearly (1998-2010), annual human casualties averaged to fewer than 13. As in India, crop-raiding by elephants makes up most of the conflicts in Malaysia, but there are important differences to explain the less violent relationship.

“Human-elephant conflicts in Malaysia are very different to those in South Asia,” says Prof. Ahimsa Campos-Arceiz in an email interview. Prof Campos-Arceiz studies the management and ecology of elephants in Malaysia. “There is a predominance of rubber and oil palm plantations, compared with more intensive smallholder paddy or other crops in India.” The lower human and elephant densities in a sparse agricultural landscape reduce “opportunities for direct contact and conflict”.

Back in India, it hurts Vivek to see his favourite animal at the epicenter of fear and anger. He studied Asian elephants for an answer to resolve the conflict. “We wanted to reduce human-elephant conflicts and instances of elephants entering farms.” He focused on deterrent methods.

But how would one deter a moving mass of muscles and bones weighing more than forty sumo wrestlers? Current methods include chili-based repellents4 and bee hives5. Vivek remembered reading of “a farmer who said he could stop elephants from entering his farm by playing tiger growls.” Most animals actively avoid predators; would elephants do so too?

It appears they would.

In southern India, Vivek and Richard Coss6 conducted a field experiment and showed that upon hearing playback of tiger and leopard growls, wild Asian elephants startled and later retreated. Speakers played the pre-recorded growls when elephants triggered sensors set on paths leading to farms. Interestingly, after the same initial startle, elephants reacted differently to the growls of the two predators.

Infrared cameras equipped with microphones. Bachahalli, Karnataka, India. by Jan Coss.

Infrared cameras equipped with microphones. Bachahalli, Karnataka, India. (credit: Jan Coss)

“With the tiger growls, the elephants retreated silently. There was no intermediate behaviour—no trumpeting, no investigating the area,” says Vivek. “With the leopard growls, there were a lot of these behaviours. You see the elephants trying to make sense of what’s going on.” Elephants trumpet and grunt “in cases of aggression, alarm and disturbances”.

The contrasting behaviours of the elephants match the threats posed by the respective predators. In India, wild tiger diets contained elephant remains and tigers reportedly kill calves, but leopards were never found to kill elephants. Against the more menacing tiger, the elephants chose the safer option of muted retreat. “With the tiger,” Vivek explains, “The elephants don’t want to make any noise because they would be betraying their position.” Against the less dangerous leopard, the elephants stood their ground and loudly vocalized their presence, but eventually left the area too.

Playback speaker  in paddy field. Ananjera, Kerala, India. by Jan Coss

Playback speaker in paddy field. Ananjera, Kerala, India. (credit: Jan Coss)

“Despite their size, elephants don’t want to mess with claws and teeth,” Vivek describes the cautious nature of the Asian elephants.

“Even if they can’t kill the elephants, they can hurt them. Elephants tend to shy away from confrontations.” Facing the uncertainty of predators in the dark, even the world’s largest land animal practices extra prudence.

Locals actively involved. (Left to right) Madhan, Rajesh and Sudhakar working on electronics.

Locals actively involved. (Left to right) Madhan, Rajesh and Sudhakar working on electronics. (credit: Jan Coss)

The study involved more than elephants. Local villagers helped with the experiment and gave feedback. “They absolutely welcomed the research,” says Vivek. “Some enterprising villagers started using the growls as an early warning system instead of having to stay up all night (to watch out for elephants).” Now, the villagers maintain a low-cost version of Vivek’s setup to deter elephants.

There is more work to be done. After repeated encounters, some elephants stopped responding to growls because there was no “credible threat”. One way to overcome the elephant’s habituation is to “play the growls from multiple directions to signify a moving tiger.” Yet even if he could greatly improve his setup, Vivek emphasized that his is one of several methods available to deter elephants, and using “the more of them, the better”. The other elephant conservationists strongly agree.

Human-elephant conflicts are complicated by the various stakeholders and their various priorities in various socio-economic and geographic conditions. Conservationists and policy-makers have tested many methods—from translocation of elephants to financial compensation, from changes in land use to physical barriers—and showed that a combination of methods is most effective to mitigate human-elephant conflicts.

“There is also a danger in people looking for silver bullets that ‘solve’ the problem of human-elephant conflicts,” Prof. Campos-Arceiz warns. “It has to be clear that such silver bullets don’t exist.” In our haste to make peace with the charismatic elephants, we tend to inflate expectations of any one method to unrealistic heights, and risk: the consequent disappointment would compromise future conservation efforts and investment.

“Appealing as they are,” says Prof. Campos-Arceiz of Vivek’s study, “measures like the use of growls are just one small part of a big picture management.”

Indeed, Vivek’s study is only one of many that aim to mitigate human-elephant conflicts. It is also a much welcomed contribution and proves that research of fundamental animal behaviours supports practical applications.

Vivek Thuppil carrying speaker for placement at Nenmeylikunu

Vivek Thuppil carrying speaker for placement at Nenmeylikunu. (credit: Jan Coss)

References and Links
1.         Doyle, S. et al. Human-Elephant Conflict—What Can We Learn from the News? Gajah 32, 14–20 (2010).
2.         Baskaran, N., Varma, S., Sar, C. K. & Sukumar, R. Current Status of Asian Elephants in India. Gajah 35, 47–54 (2011).
3.         Saaban, S., Othman, N. B., Yasak, M. N. B., Burhanuddin, M. N. & Zafir, A. Current status of Asian elephants in Peninsular Malaysia. Gajah 35, 67–75 (2011).
4.         Hoare, R. Lessons from 15 years of human-elephant conflict mitigation: Management considerations involving biological, physical and governance issues in Africa. Pachyderm 51, 60–74 (2012).
5.         King, L. E., Douglas-Hamilton, I. & Vollrath, F. Beehive fences as effective deterrents for crop-raiding elephants: field trials in northern Kenya. Afr. J. Ecol. 49, 431–439 (2011).
6.         Thuppil, V. & Coss, R. G. Wild Asian elephants distinguish aggressive tiger and leopard growls according to perceived danger. Biol. Lett. 9, 20130518–20130518 (2013).
Asian Elephant Specialist Group:  http://www.asesg.org/

Management & Ecology of Malaysian Elephants Project: http://www.meme-elephants.org/meme_home.html

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