Chennai Biodiversity Index Released – A First for Tamil Nadu

Aug 2025 : In a landmark step to strengthen biodiversity conservation, the Hon’ble Chief Minister of Tamil Nadu, Thiru. M. K. Stalin, today released the City Biodiversity Index (CBI) for Chennai. This is the first City Biodiversity Index in Tamil Nadu, providing a framework to evaluate and benchmark urban biodiversity.

The City Biodiversity Index, also known as the Singapore Index, was developed in 2008 and endorsed at the Convention on Biological Diversity (COP 9). Using 23 globally recognized indicators, the Index enables cities to measure, evaluate, and improve biodiversity conservation. Named after Singapore, which pioneered the model, it serves as a tool to align local biodiversity action with national and global commitments.

The Index acts as both a scorecard and a roadmap—helping cities assess their natural assets, track biodiversity trends, prioritize conservation, and integrate ecosystem health into urban planning.

For Chennai, this means balancing rapid urbanization with the protection of wetlands, green cover, and native species. The booklet released presents data and a roadmap for integrating biodiversity into city planning, enhancing green cover, and contributing to carbon sequestration, heat mitigation, and public health. It also promotes data-driven decisions for budget allocation, restoration projects, and community participation. This initiative is aligned with Tamil Nadu’s Green Tamil Nadu Mission, supporting sustainable growth while enhancing liveability and resilience.

Baseline Year Results (2024)

In its baseline year, Chennai scored 38 out of 72 points across 18 indicators. Highlights include:

• Proportion of natural areas: 20.12% of Chennai’s landscape still comprises natural ecosystems such as forests, wetlands, marshes, and beaches—the highest possible score under this indicator.
• Connectivity of ecosystems: Strong ecological links through wetlands, rivers, and green corridors earned Chennai top marks.
• Native bird species in urban areas: 90 bird species recorded in built-up areas secured full points, as Chennai lies along the Central Asian Flyway for migratory birds.
• Institutional biodiversity functions: Home to institutions such as Guindy National Park’s Snake Park, Semmozhi Poonga, and the MCC fauna museum, the city scored full marks on institutional capacity.

Key Biodiversity Assets

Despite rapid urbanisation, Chennai retains unique green and blue assets:

• Guindy National Park – one of India’s smallest yet most biodiverse national parks.
• Pallikaranai Marsh – a Ramsar site supporting 115 bird species, 46 fish species, amphibians, and reptiles.
• IIT Madras Campus – a remnant tropical dry evergreen forest with thriving deer, blackbuck, and over 300 plant species.
• Theosophical Society & MCC grounds – ecological refuges with rich tree diversity.

Together with Chennai’s beaches and rivers, these assets form the city’s ecological lungs, supporting climate resilience, recreation, and education.

Government Commitment

This launch builds on Tamil Nadu’s missions for ecosystem conservation, including the Tamil Nadu Wetlands Mission, Green Tamil Nadu Mission, Tamil Nadu Climate Change Mission, and the Tamil Nadu Coastal Restoration Mission.

The City Biodiversity Index for Chennai was developed in collaboration with ICLEI South Asia, the Greater Chennai Corporation, and other State and city departments. ICLEI South Asia, part of the global ICLEI network of over 100 local and regional governments, has developed the Index for 18 of the 20 Indian cities that have adopted it.

Hon’ble Chief Minister Thiru. M. K. Stalin also announced that five more cities in Tamil Nadu will prepare their City Biodiversity Index, marking the beginning of a broader journey.

Dignitaries Present

The launch was attended by:

• Thiru. R. S. Rajakannappan – Hon’ble Minister for Forest and Khadi
• Thiru. N. Muruganandham, I.A.S. – Chief Secretary to Government
• Tmt. Supriya Sahu, I.A.S. – Additional Chief Secretary, Environment, Climate Change & Forests
• Thiru. Srinivas Reddy, I.F.S. – Principal Chief Conservator of Forests, Head of Forest Force
• Tmt. Mita Bannerjee, I.F.S. – Principal Chief Conservator of Forests & Member Secretary, Tamil Nadu Biodiversity Board
• Thiru. Emani Kumar – Executive Director, ICLEI South Asia & Deputy General, ICLEI Global
• Dr. Monalisa Sen – Associate Director, ICLEI South Asia

Issued by: DIPR, Secretariat, Chennai – 9