Roadmap for Answer Writing

1. Introduction (Briefly define IAS and its relevance)

• Start by defining what invasive alien species (IAS) are: Non-native species that threaten biodiversity, ecosystem services, or human well-being (IUCN).
• Mention their increasing growth and spread, and their growing concern in India.

2. Factors Contributing to the Spread of IAS (Identify key drivers)

• Globalization and Trade: The rise in trade, travel, and transport facilitates the movement of IAS. Example: The Argentine ant spreading globally due to shipping routes.
• Illegal Wildlife Trade: Unregulated trade of exotic plants and animals contributes to the introduction of IAS. Example: Tree squirrels being introduced worldwide through the international pet trade.
• Lack of Natural Predators: IAS often thrive in new environments due to the absence of natural predators. Example: Brown tree snakes on Guam.
• High Survival Rate: Some IAS, like the Senna plant, have high survival rates due to prolific seed production, which aids their spread.

3. Threats Posed by IAS to India (Discuss the specific impacts on India)

• Threat to Natural Systems: IAS disrupt ecosystems, biodiversity, and natural processes. Example: Invasive species like Lantana camara, Prosopis juliflora, and Chromolaena odorata in the Nilgiri Biosphere Reserve threaten biodiversity.
• Economic Losses: IAS lead to losses in ecosystem services like agriculture, forestry, fisheries, etc., costing India an estimated $182.6 billion .
• Biodiversity Threats: IAS lead to local extinctions and the suppression of native species. Example: Prosopis juliflora transforming agricultural land in Tamil Nadu, forcing local populations to seek new livelihoods.
• Health Risks: IAS like the Asian tiger mosquito transmit diseases such as dengue and chikungunya, impacting public health.

4. Conclusion (Summarize the need for action)

• Emphasize the need for strategic actions like prevention of IAS introduction, better regulation of trade, and controlling the spread of these species through national initiatives (such as India’s adoption of the Aichi Target 9 on IAS).
• Highlight that IAS pose serious risks to conservation, the economy, and human health in India.

Key Facts for the Answer:

1. Definition of IAS: IAS are non-native species that negatively impact local biodiversity, ecosystem services, or human well-being (IUCN).
2. Globalization and Trade: Increased trade, transport, and tourism have facilitated IAS spread, e.g., Argentine ant in Hawaii.
3. Illegal Wildlife Trade: Tree squirrels were introduced globally through the international pet trade.
4. Lack of Natural Predators: The introduction of brown tree snakes to Guam caused the extinction of native birds.
5. High Survival Rate: IAS like Senna plants can outcompete native species due to prolific seed production.
6. Economic Loss: IAS cost India approximately $182.6 billion in losses to sectors like agriculture and forestry.
7. Biodiversity Threats: Lantana camara, Prosopis juliflora, and Chromolaena odorata affect biodiversity in protected areas like Nilgiri Biosphere Reserve.
8. Health Risks: IAS such as the Asian tiger mosquito carry diseases like Dengue and Chikungunya, posing health risks in India.

By following this roadmap, you can effectively answer the question, providing a clear explanation of the causes of IAS proliferation and its impacts on India.