India, Feb. 3 -- Entry to Periyar Tiger Reserve is not marked by any ceremonial gate. The checkpost that leads to the national park in Kerala also has no sign to announce that one has crossed into one of India's most closely guarded forest landscapes in the Western Ghats.

But guarded it is. A small group of men at the checkpost watch all vehicles entering and exiting the reserve. C Pandian, C Murugan, V Mahamayan, and R Rakkumuthu are not forest guards by training. Till the mid-1990s, they would enter the forest at night, following routes taught by family elders, to illegally collect forest produce. Now they ensure that nothing leaves the reserve illegally. And they know how to spot a poacher.

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