Invasive Alien Species (IAS)

What Are Invasive Alien Species (IAS)?

Invasive Alien Species (IAS) are non-native organisms (plants, animals, fungi, or microbes) introduced beyond their natural range, where they establish self-sustaining populations. They tend to outcompete, displace, or prey on native species, disrupting ecosystems and causing significant ecological, economic, and social impacts.

The Convention on Biological Diversity (CBD) defines IAS as species that can "arrive, survive, and thrive" in new environments, often outcompeting native species for resources. In India, the Wildlife Protection Act, 1972 defines IAS as non-native species that threaten wildlife or habitats.

Key Invasive Alien Species in India

Some of the most widespread IAS in India include:

• Animals: African catfish, Nile tilapia, red-bellied piranha, alligator gar, Red-eared Slider (North American turtle).

• Plants: Lantana, Water Hyacinth, Prosopis juliflora, and Parthenium hysterophorus (Carrot grass).

Factors Contributing to the Rise of IAS

1. Globalisation-Linked Dispersal:

   • Increased trade, travel, and transport facilitate the unintentional spread of species. For example, the Black Rat, introduced to Australia in the 1800s, is now listed as one of the "World’s Worst" invasive species by the IUCN. Similarly, the Zebra Mussel was introduced to North America's Great Lakes through ballast water.

2. Climate-Driven Proliferation:

   • Changes in temperature and precipitation create favourable conditions for invasive species, disrupting native species' life cycles. For instance, warmer temperatures may accelerate the spread of invasive insects or aquatic species like fish and mollusks.

3. Habitat Disturbance and Degradation:

   • Human activities such as deforestation, urbanization, and agriculture disturb ecosystems, making them more susceptible to IAS colonization. Parthenium hysterophorus thrives in disturbed habitats like roadsides and fields, often signaling environmental degradation.

4. Human Introduction of Exotic Species:

   • IAS are often introduced deliberately for purposes like gardening, landscaping, aquaculture, or pest control. However, these species frequently escape into the wild and outcompete native biodiversity. Water Hyacinth, originally introduced to India for ornamental purposes, has since become a major ecological threat.

Key Impacts of Invasive Alien Species

1. Ecological Impact:

   • IAS are among the top 5 direct drivers of biodiversity loss globally. They lead to the decline or extinction of native species through competition, predation, or disease. For example, the Brown Tree Snake introduced to Guam caused the local extinction of many native bird species.

2. Economic Impact:

   • IAS impose heavy financial burdens on nations, affecting sectors such as agriculture, forestry, and fisheries. Plants are the most economically damaging, with USD 926.38 billion in management costs. Water Hyacinth in Lake Victoria has depleted local fisheries, hurting economies reliant on fishing.

3. Health Impact:

   • IAS like Aedes albopictus and Aedes aegypti transmit malaria, Zika, and West Nile Fever. Other IAS, such as Parthenium, cause respiratory issues and skin allergies. Contamination of crops by invasive weeds can introduce harmful substances into food chains.

4. Threat Multiplier:

   • IAS, like Lantana, alter fire regimes, displace native flora, and reduce carbon sequestration, exacerbating climate change. This makes IAS a threat multiplier that weakens ecosystem resilience and hinders adaptation to climate change.

Global and India-Specific Initiatives for IAS Management

Global Initiatives:

1. Convention on Biological Diversity (CBD):

   • Encourages parties, including India, to prevent, control, or eradicate alien species (Article 8(h)) and offers guidelines for management.

2. Kunming-Montreal Global Biodiversity Framework:

   • Target 6 of the framework aims to reduce the impact of IAS on biodiversity and ecosystem services by 50% by 2030.

3. IUCN Invasive Species Specialist Group (ISSG):

   • Maintains the Global Invasive Species Database (GISD), offering data for the global management of IAS.

4. CITES (1975):

   • Regulates international trade of wild fauna and flora to prevent the spread of IAS through illegal trade.

India-Specific Initiatives:

1. National Biodiversity Action Plan (NBAP):

   • Focuses on the prevention and management of invasive species in India.

2. National Action Plan on Invasive Alien Species (NAPINVAS):

   • Launched by the Ministry of Environment, Forest and Climate Change (MoEFCC), this plan emphasizes prevention, early detection, control, and management.

3. National Invasive Species Information Center (NISIC):

   • Provides resources, information, and awareness on IAS in India.

4. Plant Quarantine Order, 2003:

   • Regulates the import of plants and plant material to prevent the introduction of invasive species.

Challenges in Tackling Invasive Alien Species in India

1. Underreporting & Lack of Data:

   • There is a significant underreporting of IAS-related costs, leading to underestimation of the ecological and economic impacts.

2. Resource Constraints:

   • Limited funding and human resources hinder effective surveillance, control, and eradication of IAS.

3. High Eradication Costs:

   • Large-scale removal of IAS like Lantana and Prosopis requires substantial financial and human resources.

4. Policy Gaps:

   • There is fragmented coverage of IAS under existing laws like the Biodiversity Act, Wildlife Protection Act, and Plant Quarantine Rules, with weak enforcement.

Management Strategies and Way Forward

1. Strengthening Data & Monitoring Systems:

   • Establish a centralized database for IAS, improve data collection, and track expenditure and management efforts more effectively.

2. Allocating Dedicated Resources:

   • Dedicate funding and enhance human resources to support surveillance and control efforts. Community participation can help reduce costs and increase effectiveness.

3. Community-Centric Solutions:

   • Engage local communities, as seen with the Kadar tribe in Kerala, who actively restore forests degraded by IAS. Biological control methods could also offer cost-effective alternatives to chemical control.

4. Institutional and Policy Fortification:

   • Strengthen enforcement of existing laws and improve institutional coordination. Integrating IAS management into broader policies like climate change and biodiversity action plans is crucial.

5. Public Awareness and Education:

   • Raise awareness among the public and stakeholders about the dangers of IAS and the importance of biosecurity to prevent further spread.

Conclusion

Tackling Invasive Alien Species (IAS) requires a multifaceted approach that combines strong enforcement institutions, integrated policies, and community involvement. By addressing data gaps, resource constraints, and policy inconsistencies, India can significantly reduce the ecological and economic impacts of IAS, ensuring long-term environmental and economic resilience.