Are Trenches Really the Solution to Human-Elephant conflict in Sri Lanka?

By Salik Ansar     


Day by day, elephants are losing their habitat. Hour by hour, they are losing their sources of food and water. Now, they are faced with yet another threat – falling into man-made trenches. These falls, and getting stuck in trenches, could be life-threatening. In 2021, the State Ministry of Wildlife Conservation decided to dig trenches to try to prevent elephants from crossing into human-occupied lands. However, experts fear the decision will cause more harm to the animals than good.

As a nation, Sri Lanka has suffered over the last few years: the economic crisis caused by the dwindling economy, the rise in inflation and questionable policy decisions; large-scale deforestation; mismanagement of state funds… the list goes on and on. Meanwhile, human-elephant conflict (HEC) appears to have been at its highest these last two years, with losses from both sides. While many NGOs and concerned individuals are constantly finding innovative ways to mitigate HEC, Sri Lanka’s governing body – the Department of Wildlife Conservation (DWC) – has also been busy finding solutions. After deliberation, the DWC has resorted to digging trenches to mitigate conflicts in the selected area. But as you’ll see below, we ask the question: is this really a solution?

The plight of the elephants is simple, day by day they are losing their habitat, their sources of food is decreasing, and now they are having to navigate dangerous trenches in order to feed themselves.

Who thought of this solution?

The State Ministry of Wildlife Conservation, in a sudden change of events, decided to dig trenches in an aim to prevent elephants from entering human-occupied land. To understand this sudden decision, we need to delve into the political landscape. Over two years ago a new political party came into power and with them came promises: a promise to find a solution to HEC in all affected areas in the country. 

Tring to uphold these promises, the state minister along with the President of Sri Lanka appointed a “Presidential committee” to look into many state matters, including the matter of resolving HEC. The committee had members who were wildlife experts, and they came up with an action plan for HEC mitigation, which did not include trenches. However, the state minister, who is not a wildlife expert himself, came up with the idea to build trenches around farming communities where HEC is at its highest.


Are Trenches the right solution?

According to the former Department of Wildlife Conservation head, Dr. Pilapitiya, trenches have been tried before and it has failed, not only in Sri Lanka but in many other ranges across the world. It is ineffective and inhumane.  

“In Sri Lanka, trenches have been tried in combination with DWC electric fences at the Pelawatte Sugar Company and the Lunugamvehera National Park in the south and Kathnoruwa in the northwest but proved ineffective. Private landowners in the Puttalam area have also tried out trenches but without success,” Dr. Pilapitiya points out, with evidence in hand.

The view from Thailand

Earlier this year, we initiated a collaboration with partners in Thailand to monitor elephants in agricultural fields using camera traps. Trenches have been in use for some time to keep elephants away from the pineapple and other fruit crops in the area. Having habituated to this tactic by now, it was interesting to see how the elephants behaved. In the video below, PhD student Tyler Nuckols from the University of Colorado Boulder is filming elephants entering the agricultural area using night-vision binoculars. Instead of serving as a barrier, some wiley individuals use it as a shelter for hiding from the night patrols! This is only natural, given that elephants often use dry river banks as movement paths.

Many experts feel that trenches will cause more harm than good. In Sri Lanka especially, the trenches are ineffective, as the heavy monsoonal rains fill the trenches and eventually the sides collapse. Moreover, the trenches will be a barrier to the movements of smaller animals. As is observed in other parts of the world, smaller animals will get caught in these trenches and eventually succumb to slow deaths without food, water, shelter or a means to escape.

Another point to note is the cost. Trenches are expensive both financially and environmentally. In order to build them, heavy vehicles tread into the forest, thereby damaging the sensitive ecosystem and surrounding environment. 

Despite all this, in December 2021, the DWC expedited this trenches project. By the end of the month, excavations began in Wilpattu, Lahugala, and Udawalawe, using additional DWC resources and were excavated within weeks. DWC plans to excavate more trenches in the coming months. 

How are we dealing with this now?

Many environmental NGOs banded together to stop the trenches project. The Centre of Environmental Justice (CEJ) was the pioneer in this struggle. They immediately filed multiple lawsuits against the digging of trenches in several areas in the country, including the Protected Areas under the Fauna and Flora Protection Ordinance No 2. Of 1937. They argued that trenches are not a strategy to mitigate HEC, particularly without either expert recommendations nor considerations of past experiences. The case is scheduled for a hearing this month and CEJ is hoping for a favorable response. Meanwhile, historic protests over the economic crisis has precipitated a change in political leadership. Fingers crossed that the case and future environmental decisions meet with a favorable outcome – stay tuned!


New pan-Indian study of elephant genetics reveals surprises

Herd of elephants in Terai Arc Landscape

Asian elephants were once widely distributed in India, but are now restricted to four widely separated regions: the north-western (NW), north-eastern (NE), east-central (ECI), and the southern India (SI). When you undertake the population genetics study of a wildlife species, the quality of the result is related to the design of the field sampling protocol. This is to ensure that the sampling is extensive covering different areas to avoid over-sampling of more accessible populations. When we started our population genetics study of the Asian elephant (Elephas maximus L.), we planned to collect fresh elephant dung samples from across the beats and various ranges of protected forests in India. This of course often involved traversing through inhospitable and difficult terrain with a forest staff in attendance. The first problem were the elephants themselves. To get fresh dung, one had to go close to elephants for collecting samples. This often did not go down too well with some individuals who responded to the invasion by a determined charge. We were fortunate not to have suffered any mishaps and ultimately it worked out well and we were able to collate an impressive database of elephant dung samples.

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Camera Trapping Elephants in Agricultural Areas

In partnership with Bring The Elephant Home in Thailand, we’re excited to share this picture diary from the field, by Brooke Friswold, who is a PhD student at King Mongkut University of Technology Thonburi!

Written by Brooke Friswold

It has been another busy month in Ruam Thai Village! We have erected ten camera traps on pineapple farms with the consent of local farmers in areas with reported high frequency of visitation and five on lemongrass farmland rented by Bring the Elephant Home.

In speaking with the farmers they were very excited and enthusiastic to share their experience: some of the farmers say that the elephants are coming most nights to their land, while others say it can be weekly or also come in waves, with times of high visitation followed by lapses in appearance. The farmers were very eager and interested to share and discuss where the best placement would be for the camera traps, the trails the elephants use to enter, and the recent visitations they had.

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Trialing Camera Traps 

We’re partnering with Bring The Elephant Home in Thailand to trial the potential of alternative crops to support farmers living with elephants. We’re excited to bring the first news from the field, by Brooke Friswold, who is a PhD student at King Mongkut University of Technology Thonburi!

by Brooke Friswold

The team in Thailand has been busy over the last two months – especially while director and founder of Bring the Elephant Home (BTEH) Antoinette van de Water has been in country! With the start of data collection for a subset of five BTEH rented lemongrass plots and ten community-owned pineapple plots on the horizon, equipment and methodology trialing has begun. Data collection via camera trapping is set to begin in mid-May to record baseline elephant behavior in control and experimental plots for the HECTAARE project and for Brooke Friswold’s PhD research with King Mongkut’s University of Technology Thonburi (KMUTT) in partnership with BTEH and HECTAARE. 

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Human-Elephant Conflict: Opportunities for coexistence

As the world grows more crowded, spaces inhabited by wildlife and humans tend to overlap resulting in human-wildlife conflict (HWC). While peaceful coexistence is possible, negative encounters due to various factors continue to be a challenge in conservation. Human expansion into wildlife habitat is especially problematic for Asian elephants that need a large area for their ecological needs[1]. As a result, these animals break into human settlements and cause significant losses to the community. 

Asian elephants are found to impose the highest damages with a probability of 35.1%.[4] Photo by Lokesh Kaushik on Unsplash
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