Looper Caterpillar Invasion in North East Indian Tea Agro-Ecosystem: Change of Weather and Habitat Loss May be Possible Causes?

Tea industry in India hit a record loss of tea production in 2009-11 due to widespread attack of tea defoliators, looper caterpillar pests of geometrid moths (Lepidoptera) in major tea growing eco-belt of Assam and West Bengal states. This geometrid pest complex has at least four sister species, two each of Biston and Hyposidra ; and a mixed brood of Ectropis sp. The former one was reported as a pest of tea in India since 1911, and later one reported from China and introduced to India; but Hyposidra is a novel tea pest globally, reported recently and that too first from northeast India. Through this article, we attempt to portray the severity of looper outbreak and raised two key questions; viz ., present looper outbreak as an indication of climate change in north-east India? and habitat loss may be the fundamental reason for the primary invasion of looper?