The dry side of Munnar: why Chinnar, where the dolmen trek goes, gets a tenth of the rain

Drive forty-six kilometres north-east from Munnar and the weather changes species. The tea goes, the mist goes, the permanent damp goes, and you come out into thorn scrub and dry deciduous forest on red-brown ground, with sandal in the folds. It is the same district. It takes under two hours. And it is the single most surprising thing about a Chinnar morning.

What a rain shadow does

The south-west monsoon comes off the Arabian Sea, hits the western wall of the Ghats and empties there. Everything behind the wall gets what is left. Chinnar is behind the wall. It takes on the order of 500 mm of rain a year, spread over something like forty-eight days — less than a tenth of what falls on the windward slopes an hour’s drive away, and most of what it does get arrives from the north-east monsoon between October and December, when the rest of Kerala is drying out.

For a walker this has one very practical consequence. The Chinnar treks are the only walks in this part of Idukki that are genuinely workable through June, July and August, because the rain is falling on the other side of the ridge. The trade is the other way round in March, April and May, when the open slopes are ferociously hot by nine in the morning.

A very small reserve with a very long species list

The sanctuary was constituted in August 1984 and covers 90.44 square kilometres — small — but it runs from about 400 m on the Chinnar river up to 2,522 m at Kumarikkal, more than two vertical kilometres inside one reserve. That range is why the lists are so long: on the order of 963 plant species, 225 birds, 52 reptiles and 28 mammals, from dry thorn at the bottom to shola and grassland at the top.

The animal Chinnar exists for

The grizzled giant squirrel, Ratufa macroura, is a big, shy, grey-flecked tree squirrel that in India lives essentially here — in the riverine strips of tall trees along the Chinnar and the Pambar. Chinnar holds the country’s principal population. There are also Indian star tortoises on the dry ground, an unusual white gaur population, elephant, gaur, sambar, spotted deer, bonnet macaque and Nilgiri langur.

One honest note for anyone choosing between the walks: the culture trek climbs away from the rivers onto dry hilltops, which is not squirrel country. If the squirrel is the thing you want, the river trek or the Thoovanam falls walk from the same counter goes through its actual habitat. Doing both is a comfortable day.

Eleven settlements inside the fence

Chinnar is not empty. Eleven settlements sit inside the sanctuary — seven Muthuva and four Hill Pulaya — growing ragi, chaama and citronella, and their Eco-Development Committees are who run the treks, supply the guides and take the fee. The model is deliberate: the walk exists to put money into the settlements rather than into a ticket office, and the interpretation you get on the hill is theirs.