Invasive species driving extinctions of biodiversity, causing Rs 42k crore loss: Report

Invasive alien species are irreversibly destroying natural environments at a rapid pace, with a new report putting the annual global economic cost at Rs 42,300 crore as of 2019, while affecting the livelihood of crores of people across the globe.

The latest findings from the Intergovernmental Science Policy Platform on Biodiversity and Ecosystem Services (IPBES) warn that the life, livelihood, and cultural identities of people, especially those from vulnerable communities, are at stake.

More than 37,000 alien species have been reported worldwide, with 200 new ones recorded every year. Consequently, 1215 local extinctions have been caused by 218 invasive alien species. In sensitive environments like islands, 90% of global extinctions are attributed to invasive species.

While noting that not all alien species become invasive, the report said those that begin to establish themselves at the cost of local species have a negative impact. They were a major factor in 60% of the global animal and plant extinctions while being the sole cause in 16% of the extinctions.

"Nearly 80% of the documented impacts of invasive alien species on nature’s contributions to people are also negative – especially through damage to food supplies – such as the impact of the European shore crab (Carcinus maenas) on commercial shellfish beds in New England and the damage caused by the Caribbean false mussel (Mytilopsis sallei) to locally important fishery resources in India," it said.

People's quality of life has also been affected in 85% of the documented impacts. "Health impacts, including diseases such as malaria, Zika, West Nile Fever, spread by invasive alien mosquito species like Aedes albopictus and Aedes aegypti," it said.

The report shows that 34% of the impacts of biological invasions were reported from the Americas, 31% from Europe and Central Asia, 25% from Asia and the Pacific, and about 7% from Africa. "Most negative impacts are reported on land (about 75%) – especially in forests, woodlands, and cultivated areas – with considerably fewer reported in freshwater (14%) and marine (10%) habitats. Invasive alien species are most damaging on islands, with numbers of alien plants now exceeding the number of native plants on more than 25% of all islands," it said.

Professor Helen Roy (United Kingdom), co-chair of the Assessment, said 37% of the 37,000 alien species known today have been reported since 1970. "Under 'business as usual' conditions, we project that the total numbers of alien species will continue to increase in this way. But 'business as usual' is actually unlikely. With so many major drivers of change predicted to worsen, it is expected that the increase of invasive alien species and their negative impacts are likely to be significantly greater," Roy added.

The report suggests effective management and more integrated approaches as measures to prevent future biological invasions.