Invasive Alien Species Threaten India’s Biodiversity Crisis

Recent studies show a growing threat from invasive alien species in India. These non-native plants, animals, and insects disrupt ecosystems and harm native biodiversity. Conservationists face urgent challenges in managing their spread while understanding their complex impacts.

What Are Invasive Alien Species?

Invasive alien species are organisms introduced accidentally or deliberately into new environments. They often outcompete native species, causing habitat loss and local extinctions. Examples include ornamental plants, exotic fish, and pest insects. India hosts about 139 such species, many damaging crops, wildlife, and ecosystems.

Impact on Terrestrial Ecosystems

Invasive plants like Lantana camara and Prosopis juliflora alter soil and water conditions. Lantana, introduced during colonial times, blocks movement of large herbivores, increasing human-wildlife conflicts. Prosopis, planted to combat soil salinity, consumes excessive water and reduces native grasslands. These changes disrupt predator-prey dynamics and traditional livelihoods.

Threats to Aquatic Environments

Water bodies face invasion by species such as water hyacinth, alligator weed, and alien fish introduced through aquaculture and aquarium trade. These species choke waterways, reduce oxygen levels, and threaten over 1,000 freshwater fish species. Alien aquatic species are widespread, from Kashmir’s Dal Lake to wetlands in Kerala.

Challenges in Documentation and Research

Comprehensive data on invasive species in India is scarce. Many invasions lack detailed records on spread and ecological impact. Freshwater invasion biology remains underdeveloped. This hinders effective conservation planning. Scientists call for standardised methods to assess cumulative impacts on ecosystems and species.

Conservation Dilemma – Document or Act?

Researchers debate whether to wait for full documentation before acting or to proceed with control measures alongside ongoing studies. Given the vast number of invasions and limited resources, simultaneous documentation and conservation are advised. Learning from global experiences can guide immediate management efforts.

Strategies for Management and Awareness

Developing quantitative frameworks to prioritise invasive species and affected areas is crucial. Collaboration among scientists, policymakers, and local communities is needed. Citizen science can aid in mapping invasions and monitoring changes. Integrated approaches can improve prevention, control, and eradication efforts.

Socio-Economic and Ecological Implications

Invasive species impact agriculture, wildlife conservation, and human livelihoods. They alter ecosystem functions like nutrient cycling and food webs. These changes may transform entire habitats, reducing biodiversity and ecosystem services. Addressing invasions is key to sustaining India’s natural heritage and rural economies.

Questions for UPSC:

1. Critically discuss the ecological and socio-economic impacts of invasive alien species on India’s biodiversity and rural livelihoods.
2. Examine the challenges faced in documenting invasive species in freshwater ecosystems and suggest ways to improve invasion biology research in India.
3. Analyse the role of community participation and citizen science in managing biological invasions and conserving native biodiversity.
4. Estimate the consequences of invasive plant species on soil and water resources, and how these changes affect human-wildlife conflict in India.

Answer Hints:

1. Critically discuss the ecological and socio-economic impacts of invasive alien species on India’s biodiversity and rural livelihoods.

1. Invasive species displace native flora and fauna, causing loss of biodiversity and local extinctions.
2. They alter ecosystem functions such as nutrient cycling, food webs, and habitat structure.
3. Examples like Lantana camara and Prosopis juliflora degrade habitats, affecting wildlife movement and survival.
4. Invasive pests damage crops directly and indirectly by disrupting native insect populations, impacting agriculture.
5. Changes in wildlife behavior due to habitat degradation increase human-animal conflicts, threatening rural safety and livelihoods.
6. Economic losses arise from reduced agricultural productivity, increased management costs, and loss of ecosystem services.

2. Examine the challenges faced in documenting invasive species in freshwater ecosystems and suggest ways to improve invasion biology research in India.

1. Freshwater invasion biology is underdeveloped with limited baseline data and poor species distribution records.
2. Many invasive species lack documented invasion histories, impact assessments, and spatial extent mapping.
3. Inadequate standardized methodologies hinder consistent data collection and impact evaluation.
4. Resource constraints and fragmented research efforts limit comprehensive studies across diverse water bodies.
5. Improvement requires developing standardized quantitative frameworks for cumulative impact assessment.
6. Promoting interdisciplinary collaboration, capacity building, and use of citizen science can enhance data collection and monitoring.

3. Analyse the role of community participation and citizen science in managing biological invasions and conserving native biodiversity.

1. Local communities possess traditional knowledge useful for early detection and reporting of invasives.
2. Citizen science initiatives can create extensive atlases of invasive species distribution at low cost.
3. Community involvement encourages awareness, ownership, and cooperation in control and eradication efforts.
4. Collaborative approaches help integrate socio-economic concerns with ecological management strategies.
5. Engagement across stakeholders ensures diverse perspectives and more effective, inclusive conservation planning.
6. Such participatory models improve monitoring frequency and spatial coverage beyond what scientists alone can achieve.

4. Estimate the consequences of invasive plant species on soil and water resources, and how these changes affect human-wildlife conflict in India.

1. Invasive plants like Prosopis juliflora consume excessive soil moisture, reducing water availability for native species.
2. Lantana camara alters soil properties and creates dense thickets, impeding movement of large herbivores.
3. Changes in soil porosity, acidity, and water turbidity disrupt native plant growth and ecosystem functions.
4. Degraded habitats force wildlife to move closer to human settlements in search of food and water.
5. This displacement increases encounters and conflicts between humans and wild animals, threatening lives and crops.
6. Such ecological changes undermine traditional pastoralist and farming practices, affecting rural livelihoods.