An intergovernmental panel report on biodiversity has raised concerns over the devastating impact of the invasive Caribbean false mussel (Mytilopsis sallei) on Kerala’s native clams and oysters, crucial for local fisheries.
The Caribbean false mussel, originally from the Atlantic and Pacific coasts of South and Central America, has rapidly proliferated in Kerala, displacing native species and disrupting the local ecosystem. Notably, it has also outcompeted another invasive species, the American brackish water mussel (Mytella strigata), which previously posed a significant threat to the region’s waterways.
Researchers speculate that the Caribbean false mussel may have entered Indian waters through ships and subsequently spread to estuaries via smaller fishing vessels frequently traveling between coastal oceanic waters and Kerala’s fishing harbors.
An intriguing hypothesis presented in the report suggests that the spread of this invasive species might have been triggered by tropical Cyclone Ockhi, which struck the Kerala coast in 2017, potentially carrying the Caribbean false mussel into new habitats.
The report, released by the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES), highlights numerous case studies of invasive species contributing to the extinction of 60% of global plant and animal species. It emphasizes that the economic cost of invasive alien species exceeded $423 billion annually in 2019, with costs increasing significantly since 1970.
Invasive alien species are recognized as one of the five major drivers of biodiversity loss, alongside land and sea use changes, direct species exploitation, the climate crisis, and pollution. Over 37,000 alien species have been introduced to various regions and biomes worldwide due to human activities. Of these, more than 3,500 are considered harmful invasive alien species, posing significant threats to nature, human well-being, and quality of life.
While some alien species were intentionally introduced for their perceived benefits, the report indicates that nearly 80% of documented impacts from invasive alien species on ecosystems and biodiversity are negative. The most frequently reported impact is a reduction in the food supply, affecting various taxa and regions.
Additionally, the report underscores that invasive species also have health implications, contributing to the spread of diseases like malaria, Zika, and West Nile Fever, primarily transmitted by invasive alien mosquito species such as Aedes albopictus and Aedes aegypti.
“Invasive alien species have been a major factor in 60% and the only driver in 16% of global animal and plant extinctions that we have recorded, and at least 218 invasive alien species have been responsible for more than 1,200 local extinctions. In fact, 85% of the impacts of biological invasions on native species are negative,” noted Anibal Pauchard, co-chair of the assessment, in a statement.
