The Nilgiri Hills: Where Three States Meet

1.1 Where are the Nilgiri Hills, and how tall are they?

The Nilgiri Hills sit at the tri-junction of Tamil Nadu, Kerala, and Karnataka. “Nilgiri” translates roughly to “blue mountains,” reflecting a bluish haze the hills genuinely take on from a distance.

• They form part of the Western Ghats, in southern India.
• The Nilgiris also connect the Western Ghats toward the separate Eastern Ghats, making them a genuine geographic hinge point in the Peninsula.
• Much of the range sits as a rolling high-altitude plateau, not a single sharp ridge, letting both shola forest and open grassland coexist there.
• The plateau’s height gives it a genuinely cool climate year-round, unusually mild for a location this close to the tropics.
• Their highest peak, Doddabetta, rises to 2,637 metres.
• Because of this tri-state junction, wildlife and forest management here genuinely requires close coordination across all three neighbouring state governments.

2.1 Why does 1986 matter here?

The Nilgiri Biosphere Reserve, declared in 1986, was India’s first biosphere reserve.

• It covers a genuinely vast area spanning all three neighbouring states, not just one.
• UNESCO later added it to its own World Network of Biosphere Reserves, giving it international recognition beyond India’s own designation.
• Parts of the Nilgiris also genuinely fall within the Western Ghats UNESCO World Heritage Site, recognising the range’s exceptional biodiversity value.

3.1 What makes the shola-grassland ecosystem distinctive?

The Nilgiris have a distinctive shola forest-grassland ecosystem. Shola forests are dense evergreen patches found in valleys, surrounded by rolling grasslands.

• Cold air pools in the sheltered valleys, letting evergreen trees survive there, while exposed ridges nearby stay too harsh for anything but grass.
• This exact shola-grassland mosaic occurs only in a few high-altitude pockets of the southern Western Ghats — a genuinely rare ecosystem type.
• Shola forests also help regulate local water flow, acting as natural sponges that release water gradually even in the dry season.
• The Nilgiri tahr, an endangered species, is endemic to these grassland-shola habitats.
• The tahr is a goat-like mountain ungulate that climbs steep, rocky grassland slopes with genuine ease.
• It is officially Tamil Nadu’s state animal, so its conservation genuinely carries real political and cultural weight, well beyond pure ecology.

4.1 Who are the Nilgiris’ indigenous communities?

Indigenous tribes, including the Todas, Kotas, and Kurumbas, live across the region.

• Each community traditionally held a distinct role, from pastoralism to craft and trade, forming an interdependent hill economy long before roads or railways arrived.
• The Badagas, another major Nilgiri community, historically focused on settled agriculture, and genuinely remain the largest indigenous group in the hills today.
• The Todas graze buffalo on the mountain grasslands and treat the shola forests as culturally significant.
• The Todas build distinctive barrel-vaulted huts and dairy temples, a recognisable feature of the Nilgiri landscape today.
• The Toda population remains genuinely small, numbering only in the low thousands overall, making their culture especially vulnerable to outside pressure and change.

5.1 Why did the tahr population decline for decades?

The Nilgiri tahr’s population had actually declined over the decades in earlier range-wide counts.

• Grassland loss to agriculture, tourism, and invasive species like wattle and eucalyptus was the main driver.
• Wattle and eucalyptus plantations dry out the soil and crowd out native grass, so tahr and other grassland species lose feeding ground as a direct result.
• These trees were originally planted deliberately, for timber and fuelwood; their spread beyond planned areas became an unintended, lasting problem.

6.1 What actually reversed the decline?

This decline happened despite the region’s biosphere reserve status since 1986.

7.1 What did the 2026 survey find?

Tamil Nadu’s third synchronised Nilgiri tahr survey counted 1,364 individuals in April 2026, up 4.68% from 1,303 in 2025. (Source: The New Indian Express, June 6, 2026)

• This marks a rise of over 32% since 2024. Officials credit Project Nilgiri Tahr, launched in October 2023, for the recovery.
• The Anamalai Hills held 44.87% of Tamil Nadu’s tahr population, with the Nilgiris landscape holding another 29.25%.
• This is a genuine, recent reversal of the long decline described above, though officials still flag forest fires as an ongoing threat.