Invasive species, the silent intruders of ecosystems, are wreaking havoc across India’s natural landscapes. Defined as non-native organisms that disrupt native biodiversity and ecological balance, these invaders pose significant threats to both wildlife and human livelihoods. Their rapid proliferation often outpaces the ability of native species to compete, leading to altered habitats and ecosystem functions.

A recent study published in the Journal of Applied Ecology revealed alarming statistics: approximately 66 per cent of India’s natural systems face the threat of invasive species. Conducted through a national-level survey, the research identified 158,000 plots spanning 358,000 square kilometres of wild areas invaded by alien species. Among the 11 high-concern invasive plant species detected in 20 states, notable invaders include Lantana camara, Prosopis juliflora, and Chromolaena odorata.

The impact of these invaders extends beyond mere displacement of native flora. Invasive plants like Lantana camara, known for their dense thickets, smother native vegetation, reducing food and habitat for herbivores crucial to the ecosystem’s balance. Such alterations ripple through the food chain, jeopardising apex predators like tigers, whose survival hinges on robust herbivore populations.

“The survival of apex predators like tigers depends on habitats free from the negative impacts of plant invasions,” remarked Qamar Qureshi from the Wildlife Institute of India (WII), emphasising the broader ecological implications. Project Tiger, originally designed to monitor carnivore populations, now faces new challenges as invasive species reshape habitats essential for these iconic species.

The economic toll is equally staggering, with estimates suggesting biological invasions could cost India up to $182.6 billion. Invasive species alter soil moisture regimes, disrupt natural disturbance cycles, and thrive in areas modified by human activities. This disruption exacerbates pressures on already vulnerable ecosystems, increasing the risk of species extinctions and compromising essential ecosystem services.

Examples abound of invasive species making their mark across India’s diverse landscapes. From the expansive reach of Lantana camara in the Nilgiri Biosphere Reserve to the dense invasions of Prosopis juliflora in the Southern Eastern Ghats, these plants reshape natural environments wherever they take hold. Their ability to thrive in varied climates—from arid savannas to moist evergreen forests—underscores the urgency of effective management strategies.

Efforts to mitigate these impacts must go beyond removal efforts alone. Context-sensitive restoration, stakeholder engagement, and adaptive policies are essential to combat the complex challenges posed by invasive species. “Managing invasive species demands more than mere removal—it necessitates holistic approaches that enable positive changes,” stressed Ninad Avinash Mungi from Aarhus University, underscoring the need for collaborative action.

The global perspective on invasive species reinforces the urgency of India’s situation. Addressing the menace of invasive species requires swift and coordinated action. From strategic restoration initiatives to robust policy frameworks, proactive measures are crucial to safeguarding India’s biodiversity and natural heritage. As the country grapples with these challenges, fostering resilience and adaptive capacity will be key to preserving its rich ecological tapestry for future generations.

The writer is an environment enthusiast and an animal welfare activist, and is the Founder of Kaloms Ideas Welfare Foundation. She is also a chartered accountant.