- Sri Lanka’s agriculture suffers significant losses due to crop-raiding wildlife, especially elephants, monkeys, wild boars, giant squirrels, porcupines, and peafowls.
- An island-wide, citizen-assisted count of wild animals on agriculture land and in home gardens is planned for Mar. 15, lasting five minutes starting 8 a.m.
- Crop-raiding wild animals remain a significant challenge in Sri Lanka as cultivations suffer but the problem is exacerbated by limited scientific data, prohibitive costs and public opposition to certain solutions like culling.
- The forthcoming survey excludes major nocturnal raiders such as elephants, wild boars, and porcupines, raising questions on the effectiveness of the exercise, while some consider it a step in the right direction.
COLOMBO — In December 2024, Sri Lanka’s newly appointed minister of agriculture K. D. Lalkantha told the Parliament that farmers should have the right to take action against crop-raiding wild animals. His comments drew backlash, particularly from environmentalists who termed the minister’s remarks harmful and an invitation to kill wildlife at will. While opinions remain divided on the efficacy of taking such a course of action amidst growing crop raids by wildlife, the long-standing problem needs to be addressed.
Amid calls for an urgent solution, the new administration formed a 15-member committee and called for public responses to solving the issue of crop-raiding pests. The first snag the committee ran into is the lack of population data of these wild animals, a key challenge to seeking a solution. Based on the committee’s recommendations, an island-wide citizen-assisted count of crop-raiding animals is set for Mar. 15 at 8 a.m., lasting just five minutes.
Due to limited labor, authorities are urging citizens to record sightings of wild animals from their farmlands, home gardens or workplaces within the allotted five minutes. The survey will use the ‘point count’ methodology, chosen after an unpublished pilot study found 8 a.m. to be an active period for many species, explains Lasantha Sandika, director of Sri Lanka’s Hector Kobbekaduwa Agrarian Research and Training Institute (HARTI).
A 2022 unpublished HARTI study estimates that wild animals caused crop losses of 144,989 metric tons of produce and 93 million coconuts, amounting to 30.2 billion Sri Lankan rupees ($87.5 million). The primary wildlife culprits include elephants (Elephas maximus), multiple monkey species, wild boars (Sus scrofa), giant squirrels (Ratufa macroura), porcupines (Hystrix indica) and peafowl (Pavo cristatus).
Common crop-raiders
Among them, the study shows elephants are among the most destructive, damaging rice, maize, bananas, sugarcane and vegetables. Wild boars devastate rice, maize, and root crops, while monkeys raid fruit, rice and vegetable fields. Toque macaques do not hesitate to enter unguarded homes to steal food during the day and are disliked by the villagers. The porcupines target root crops and also damage coconuts and young plants. The peafowls also contribute to losses, attacking fields, fruits, and vegetables.
The survey excludes nocturnal activities by animals such as elephants, wild boars, and porcupines.
Recent increase
Crop-raiding by wild animals has increased significantly over the past few decades, says R. W. Dharmasena, a rice farmer from Alawwa in northwestern Sri Lanka. Peafowls, once rare in the area, have recently become a major threat to paddy fields. In nearby villages, houses need to be fully secured to prevent toque macaques from breaking in, he tells Mongabay.
Beyond the damage caused to crops, monkeys also threaten native wildlife by raiding bird nests and feeding on eggs. While Dharmasena says he appreciates peafowls for preying on snakes, he worries that the unchecked rise of these crop-raiding species could reduce native wildlife and create an imbalance in his environment.
Concerns over accuracy
Sri Lanka is home to three species of monkeys who frequently interact with humans: the endemic toque macaque (Macaca sinica), gray langur (Semnopithecus priam) and the endemic purple-faced leaf monkey (Semnopithecus vetulus). The toque macaque and gray langur are particularly problematic, but distinguishing between the two species may pose challenges for survey participants, says A. L. Sandika, director and chief operating officer at the Hector Kobbekaduwa Agrarian Research and Training Institute (HARTI).
Public skepticism about the survey has led to widespread social media ridicule, with concerns being expressed about five minutes being inadequate for such an exercise. However, Sandika points out that a brief count minimizes double counting as animals move about fast. Larger landowners are requested to involve family members, while government officers are set to monitor public spaces.
However, environmentalists worry about the possibility of exaggerated numbers in locations identified as high-conflict areas. Sandika, however, says he believes the contrary and that the application of the proper methodology may result in an undercount than an exaggerated number.
Experts weigh in
Buddhi Marambe, a professor of crop science of the University of Peradeniya, Sri Lanka, says that crop-raiding animals have reached a tipping point due to unchecked population growth. While scientific survey methods exist, public participation can still provide useful baseline data, he says. “The results should be interpreted by experts in animal behavior and conservation science before taking any actions based on the results,” Marambe tells Mongabay.
Following the controversy triggered by the agriculture minister’s statement in Parliament, the government attempted to carry out a sterilization program for monkeys in Matale in central Sri Lanka.
The monkeys were captured and taken to a facility in Girithale in north-central Sri Lanka. However, the island has only a handful of wildlife veterinaries and the facilities are limited to be able to provide an effective sterilization exercise. After just a month, the government announced it will discontinue the monkey sterilization program.
Primatologist Wolfgang Dittus, who is based in Sri Lanka, sees some merit in the survey, as it could engage the public in matters of wildlife and potentially test longstanding observations about monkey numbers near human habitations.
However, he points out, counting monkeys will do very little to address human-monkey conflict and proposes, instead, creating awareness on protecting property and reducing monkeys’ access to human foods being more meaningful. He says moves to translocating problematic monkeys is not the best idea as they would prove a burden to villagers in rural areas, eventually getting killed either by people or territorial resident monkeys.
The solution to this no-win situation is to prevent monkey population growth by desisting from purposely feeding monkeys and preventing the littering of food that spurs their numbers, Dittus tells Mongabay.
As the debate rages on, the success of the five-minute count remains uncertain, but experts agree that better data is essential for informed decision-making on crop-raiding wildlife management. However, at least in the case of primates, resolving human-wildlife conflict requires education and counting monkeys has limited application, says Dittus.
Banner image: A troop of endemic, purple-faced leaf monkeys (Semnopithecus vetulus) making a coconut tree top their home. Image by Priyanath Kotalawela.
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This story first appeared on Mongabay
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