On-line trade of aesthetic exotic organisms: sword of Damocles?

Exotic organisms introduced into non-native ecosystems may invade and affect the native biodiversity, which might lead to serious ecological, economic and sociological threats. Among the various pathways of introduction of non-native species, on-line pet trading is the most recently emerged method which facilitates rapid introduction of exotic species. Though on-line trading has become an influential factor for the growth of world economy in the current scenario, its role in the introduction of exotic species and their subsequent consequences in countries like India is least studied. In this article we delineate the role of on-line trading in importing alien species to our doorsteps, which can cause serious threats to India's biodiversity and economy in near future. Our web survey revealed that 910 varieties of exotic fishes and 14 exotic animals are being sold through unregulated on-line trading in India. The number of exotic species recorded in this survey is not conclusive and may be the tip of the iceberg when compared to the ground reality in the country. Our interaction with the local people exposed that most of the sellers and buyers are naive about the consequences of introducing these species into our native ecosystems. Our extensive field survey revealed that most of the exotic fishes were maintained in open tanks and no regulations were adopted to curtail their escape during maintenance of tanks, rains and floods. Greater abundance and biomass of Pterygoplichthys pardalis than the native edible fishes in freshwater ecosystem in Madurai, Tamil Nadu, South India is an example of invasion of ornamental fish into the wild. Bringing policy-level changes, multidimensional approaches to regulate on-line trade of exotic species will pave the way for protecting the native ecosystem from encroachment of exotic organisms.