A recent study has revealed significant declines in many of India’s bird species, underscoring the urgent need for targeted and sustained conservation efforts. The State of India’s Birds 2023 report, produced by a consortium of leading research institutions and conservation organisations, assesses the status of 942 bird species using data contributed by thousands of birdwatchers through the eBird citizen science platform.
This report represents one of the largest biodiversity monitoring efforts in the Global South. Leveraging semi-structured data collected by citizen scientists, the researchers overcame common challenges such as uneven geographic coverage and variation in observer effort. To address these biases, the team developed a robust analytical framework that allows scientifically sound conclusions to be drawn from volunteer-generated data.
“Our findings reveal a sobering truth: India’s diverse bird populations are facing significant declines, underscoring an urgent need for concerted conservation efforts”, said Vivek Ramachandran, Fellow, Wildlife biology and conservation program at NCBS and an author of the study.
Key Findings:
- 204 specieshave suffered long-term declines, and 142 speciesare currently declining.
- 178 specieshave been classified as High Conservation Priority
- 323 speciesas Moderate Priority
- 441 speciesas Low Priority
Birds with specialised diets, such as those feeding on vertebrate prey, carrion, or invertebrates, have declined the most, averaging over 25% long-term population loss. In contrast, species dependent on fruits or nectar have remained stable or even increased.
Habitat specialists from grasslands, scrublands, and wetlands have experienced the steepest declines. Winter migrants to India have also declined more sharply than resident species, raising further alarm.
Innovations in Data Handling:
One of the main challenges of using eBird data is the variable effort put in by citizen scientists. Rather than standardising birding duration or distance, the team standardised analyses based on the number of species reported per checklist, which improved the comparability of data.
A key strength of eBird is the completeness factor—birdwatchers can mark checklists as “complete”, indicating that all detected species were reported. The team used only these checklists to ensure data integrity. All the software and analytical methods developed for the project are open source, allowing researchers worldwide to build upon them.
“The analysis leveraged citizen science data from the eBird platform and developed a robust methodology to clean, organise, and analyse this semi-structured data to overcome biases. This framework allowed for the assessment of a larger number of bird species than previously possible and is intended to serve as a blueprint for regions with limited resources for traditional surveys,” said Ramachandran.
This study sets a new standard for biodiversity assessment in regions with limited access to traditional survey methods. It demonstrates how citizen science, when combined with scientific rigour and computational tools, can fill critical knowledge gaps at scale.
The State of India’s Birds Partnership continues to welcome scientists interested in semi-structured data analyses and conservation. As the effort evolves, it offers a platform for collaboration and advancement in biodiversity monitoring globally.
About National Centre for Biological Sciences (NCBS-TIFR)
NCBS is a centre of Tata Institute of Fundamental Research (TIFR; an autonomous institute of Department of Atomic Energy, Govt. of India). Faculty and students at NCBS pursue high-quality multidisciplinary and multiscale research in the frontier areas of biology, ranging across all scales of size, complexity, and time- from molecules to ecosystems and nanosecond to evolutionary timescale. A major focus of their research is on ecology, biodiversity, and conservation, carried out using advanced knowledge and techniques. NCBS houses state of the art facilities-among the best in the world and hosts an environment conducive for innovative research and scientific collaborations.
Link to the study: https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecs2.70290
For more details, contact
Vivek Ramachandran
Email: vivekr@ncbs.res.in
Ashwin Viswanathan
Email: ashwinv@ncf-india.org
