Environmental impacts of invasive species greatest in global south, study finds

New Delhi, Jul 24 (PTI) Impacts of invasive species, which spread aggressively and are not native to a region, on biodiversity are the greatest in the global south, where rapidly developing economies, weak governance, and limited management capacity leave ecosystems most vulnerable to biological invasions, a study has found.

The spread of invasive alien species is said to be a major driver of global biodiversity loss. Previous estimates suggest that invasive species have contributed to roughly 60 per cent of documented species extinctions and hundreds of billions of dollars in economic damages.

Researchers, including those from the University of Fribourg in Switzerland, said the findings “overturn the widely held assumption that the most severe

impacts of IAS are concentrated in the Global North”.

They added although the distribution of non-native species around the world is increasingly well documented, geographic patterns of their environmental impacts remain poorly understood.

Most global assessments rely on indirect indicators, such as invasive species richness or trade volume — global trade can introduce non-native species — which have suggested that impacts are greatest in the global north, they said.

However, the pattern may reflect an underreporting in the global south, rather than true differences in ecological impact, the team added.

The researchers combined the Global Impacts Dataset of Invasive Alien Species (GIDIAS), which compiles more than 22,000 documented impacts from more than 3,300 invasive species across 172 countries, with global datasets of alien species distributions.

The authors “calculated average impact severity per country and found that it is higher in the Global South (where research effort is generally lower) despite more than twice as many reports in the Global North.” “Weak governance and limited management capacity are the main drivers of high impact severity. Emerging economies with rapid economic growth but poor governance are particularly vulnerable,” they said.

The team also found that for 164 invasive species causing impacts in both global north and global south, the average impact severity of the same species was 50 per cent higher in the Global South.

The result indicated that local conditions in the Global South, including governance, facilitate more severe impacts, they said.

The researchers added that failure in recognising impacts of invasive species in the Global South “diverts attention away from the most threatened regions”. PTI KRS KRS MAH MAH