GUWAHATI, Oct 12: Assam’s elephants are roaming far beyond forest boundaries, traversing tea gardens, farmlands, riverine grasslands and human settlements across vast landscapes, a GPS telemetry study has revealed, underscoring the urgent need for a landscape-wide approach to elephant conservation and human-elephant conflict management.
The study found that the annual home range of some elephant herds exceeds 500 sq km, with one herd covering as much as 890 sq km. It also identified tea plantations as important secondary habitats, where elephants spend considerable time for movement and shelter.
Conducted by the Assam Forest Department in partnership with WWF-India between April 2021 and June 2026, the study tracked four female-led herds and one solitary male across the high-conflict districts of Udalguri, Sonitpur and Biswanath.
The exercise marks a first-of-its-kind effort to understand the ranging patterns and habitat use of Asian elephants in Assam.
The findings show that elephants navigate a complex mosaic of forests, tea estates, agricultural lands and human settlements, with all collared elephants expanding their ranges significantly during the monsoon and post-monsoon seasons, apparently due to crop availability.
Seasonal movements also varied across districts. The Udalguri herds displayed distinct seasonal patterns, with their average home ranges larger than those of the herds monitored in Sonitpur. One herd in the study recorded an annual home range of 890 sq km.
In Sonitpur, satellite telemetry revealed that the two collared elephants belonged to separate herds whose home ranges partially overlapped. Together, the elephants covered more than 500 sq km annually. Their ranges remained relatively restricted, at around 30-50 sq km, between January and September, before expanding dramatically to 450-500 sq km during the post-monsoon months.
During this period, the elephants used the Nameri-Sonai Rupai-Arimora Chapori corridor to reach the Brahmaputra river, highlighting the importance of connected habitats and movement corridors in sustaining elephant populations.
The solitary male tracked in Biswanath exhibited an even wider range than the monitored elephants in Sonitpur and Udalguri. His ranging area covered 947 sq km, extending approximately 40 km southeast towards Gohpur, 18 km south and 23 km southwest across the Brahmaputra’s riverine chaporis, comprising grasslands and river islands.
In Udalguri, transboundary movement into Bhutan was observed as both the herds went to Bhutan during the dry season, potentially due to the lack of water availability on the Indian side.
The study also points to variations in elephant movement between day and night, depending on land use. Elephants may move more extensively at night through human-dominated areas, while showing more diurnal movement in natural habitats.
Amidst anthropogenic pressure on forests and traditional wildlife habitats, tea plantations are emerging as significant spaces for elephant movement, foraging and habitation. All four collared female elephants and their herds extensively used tea gardens in Sonitpur and Udalguri, highlighting the role of these estates in supporting elephant movement across the landscape.
However, their near-year-round presence in tea plantations also raises concerns about accidental encounters between people and elephants, as well as the risk of electrocution.
“The near-annual presence of elephants in the tea plantations necessitates proactive steps to reduce the risk of accidental encounters between people and elephants, as well as interventions to prevent electrocutions,” the study noted.
It recommended improved lighting in tea estate settlements and along adjoining roads to enhance visibility at night, allowing residents to detect approaching elephants and avoid sudden encounters.
The study also suggested restoring low-lying areas within tea estates where tea has not been planted, thereby improving forage availability for elephants.
With many tea estates installing energised fences to prevent elephants from entering tea-growing sections, the researchers stressed the need to align such barriers carefully. While fences can help secure vulnerable areas, poorly planned installations could obstruct traditional elephant routes and disrupt movement across the landscape.