Exotic South American Apple Snail discovered in Mumbai

An international team of wildlife biologists based out of Mumbai, Karnataka and Scotland, in the UK, discovered a breeding population of the exotic South American Apple Snail, Pomacea diffusa, in the waters of Mumbai.

Popularly known as Spike-topped Apple Snail, its discovery was part of their ongoing research on urban wildlife and the ecology of introduced species in the Mumbai region. The landmark study is funded by Scotland-based conservation organisation ‘Caledonian Conservation Limited.’

The discovery was published in the October-December 2020 issue of 'ELA Journal of Forestry and Wildlife', a peer reviewed science journal, which is also the official journal of Maharashtra State Forest Department. The study team was steered by the principal author and lead researcher, Javed Ahmed, in collaboration with Scotland-based wildlife biologist Chris Cathrine; Moodbidri-based environmentalist and surgeon, Dr Krishna Mohan; naturalist, arachnologist and landrace dog expert, Rajashree Khalap and wildlife photographer and researcher, Bhushan Jadhav.

Javed Ahmed, along with his colleagues, Dr Krishna Mohan and Rajashree Khalap, had earlier discovered many new species of spiders in the country. “Prevalence of Spike-topped Apple Snails in Mumbai and other parts of India is a direct result of the aquarium trade, either as accidental or deliberate releases from home aquaria. However, compared to other snails in the genus Pomacea, which are native to South America, they are not dangerously invasive and are generally considered harmless,” informed Dr Krishna Mohan, who co-authored the paper.

The discovery of this foreign species of snail raises many issues of concern to native ecology. Though Spike-topped Apple Snails are considered harmless, the same is not true for other species which are known to proliferate through the aquarium trade. “Other species of apple snails in the genus Pomacea also make their way into aquarium trade. One such species, Pomacea caniculata, popularly known as Channeled Apple Snail, is particularly troublesome as it has a voracious appetite for aquatic vegetation. If established locally, Channeled Apple Snails can wreak havoc on riceland ecosystems. They also prey on amphibian eggs and can greatly damage native aquatic ecosystems,” Javed Ahmed said.

Dr Krishna Mohan said: “Though the Channeled Apple Snail is yet to show up in our waterways, the discovery of Spike-topped Apple Snails does highlight the important concern to regulate global aquarium trade and promote responsible aquarium culture. The aquarium trade in India needs to be closely monitored and wisely regulated to prevent any future potential ecological disasters due to the introduction of dangerously invasive species. Those who keep aquariums should be responsible," Dr Krishna Mohan said.

“Be a responsible hobbyist. Ensure that fish, plants and aquatic invertebrates are bred, legally and ethically sourced. Always strive to emulate natural conditions. Do not sell, acquire or keep endangered or protected species and do not release exotic fish, plants, and invertebrates in local water bodies,” he appealed.