Invasive alien species (IAS) are those plants, animals, or microorganisms that do not naturally belong to a region but, once introduced, spread quickly and disturb the local balance.

Key highlights of the study 

• Expansion of IAS: Annually, ~15,500 km² natural areas in India are invaded by at least one new IAS.
  • Invasive alien plants have already doubled their range in ecologically sensitive regions eg. Western Ghats(WGs), Himalayas and north-east.
• Impacting Natural Ecosystem: Almost 2/3rd of India’s natural ecosystems now contain at least 11 major IASs, eg. Lantana camara, Chromolaena odorata, Prosopis juliflora etc.
• Climate Change–Driven Spread: Wet-biome invaders eg. Ageratina adenophora, Mikania micrantha expanded with rising temperatures and declining soil moisture 
  • Conversely, dry biomes invasions e.g., Xanthium strumarium increased with increasing rainfall.

Impacts of IAS

• Threatening Livelihood: eg. Prosopis juliflora often block access to pasture, firewood and water and can cause respiratory illness.
• Threat to Wildlife- eg. By 2022, invasions had impacted more than 1 lakh sq km of tiger habitat.
• Threat to Biodiversity- eg. Lantana camara suppressed native vegetation in India's Western Ghats.
• Economic -India’s economic losses from IASs (1960 -2020) is $127.3 billion.