you see a lot of butterflies hovering around coffee plantations. The reason is the plantations have scattered stands of trees for shade. And a change in ecology can affect their numbers.

Over the past five years, the native trees in the coffee plantations at Chikmagalur in Karnataka have been replaced with the exotic silver oak. A study from Bangalore, which looked into how the change has affected butterflies, says it hasn't made any considerable difference. Silver oak is popular with plantation owners since it grows rapidly and provides valuable timber.

The study has observed that distance of coffee plantations from protected areas does affect their population. The researchers found that coffee plantations closer to forests had better butterfly diversity than those further away. With 37 endemic butterfly species in the Western Ghats, the non-forest landscapes should be made butterfly friendly and conserved by having a variation in vegetation, the study says.

The Western Ghats in Chikmagalur are a patchwork of forests and plantations of varied kind, including tea. Researchers say it will be a good idea to have coffee plantations close to protected areas so that the coffee plantations can act as corridors allowing butterflies to move from one fragment to the other and provide space for activities such as basking, mating and roosting. "Converting all tea plantations to coffee may not be feasible as coffee offers only seasonal employment. But perhaps, the conversion of coffee to tea near protected area could be stopped,' says Ajith Kumar of the National Centre for Biological Sciences, Bangalore.

The researchers suggest identifying the kind of land use that promotes greater plant and animal biodiversity to be a workable option. The study was published in January's edition of the journal Animal Conservation.