Knowledge Nugget: What makes Delhi one of the world’s most bird-diverse capitals?

Key Takeaways:

1. The atlas was developed by the Delhi Forest Department, Bird Count India, World Wide Fund for Nature (WWF)-India and other partner organisations, with the participation of birdwatchers, students, researchers, forest staff and citizen volunteers.

2. According to the atlas, “The Delhi Bird List now stands at 471 species”, excluding another 22 species that have not been re-recorded since 1975.

3. The atlas cites the rare mix of the city’s geography, including the northern edge of the Aravallis, proximity to the western Himalayas, the Yamuna and Sahibi floodplains, and its location near the Central Asian Flyway (CAF) — a key bird migration route stretching from the Arctic down to the Indian Ocean — as the primary reason behind the bird diversity.

4. The atlas covers 11 per cent of Delhi’s area in its sampling design. The survey started in January 2025, takes place twice a year, in winter and summer, and will run for at least two years. 

5. In the first year, 221 species were recorded across the city, including 200 in winter and 152 in summer. Of these, 126 were resident species, 81 were winter migrants and 14 were summer migrants. Nearly half the recorded bird assemblage comprised invertebrate feeders, that is, 108 species or 48.87 per cent. Plant and seed feeders accounted for 37 species, omnivores for 34, vertebrate and carrion feeders for 33, and fruit and nectar feeders for nine.

6. The atlas also records 18 endemic bird species, that is, species found exclusively in one specific geographic region. It also lists several vulnerable bird species, including the Endangered Egyptian Vulture and Black-bellied Tern, the Vulnerable River Tern and Common Pochard, and Near Threatened species such as the Black-tailed Godwit, Ferruginous Duck, Painted Stork, Black-headed Ibis and Oriental Darter.

7. Experts associated with the atlas attribute Delhi’s bird diversity to the city’s position at an ecological intersection: the Ridge brings the Aravalli landscape into the Capital, while the Yamuna floodplains and associated wetlands provide refuge for waterbirds and migrants. 

8. The city’s proximity to the western Himalayas, meanwhile, facilitates seasonal movement. The atlas notes that Delhi “lies almost at the heart of the Central Asian Flyway”, making it “a seasonal haven for species arriving from as far as Central Asia and the Arctic”.

9. Meanwhile, the atlas also describes Delhi as “a meeting point of history, geography, and biodiversity”, noting that such diversity persists despite the pressures of one of the world’s most populous urban regions. It also underlines the importance of protecting “the green and blue spaces that sustain it”. The Yamuna floodplains, in particular, are identified as a key ecosystem for conservation and habitat restoration.

BEYOND THE NUGGET: First-ever grassland bird census

1. In May last year, a survey to record the grassland bird population in Kaziranga National Park was undertaken by a team of forest officials, scientists, and conservationists. It was the “first-ever grassland bird census” conducted in Assam’s Kaziranga National Park. 

2. The grassland bird census recorded a total of 43 grassland bird species, including 1 Critically Endangered, 2 Endangered, and 6 Vulnerable species, according to the IUCN Red List. 

3. A new methodology was deployed in the survey. According to Kaziranga National Park Director Dr. Sonali Ghosh, the use of passive acoustic recording monitoring was the highlight of the survey.

The national park authorities have been particularly excited by the discovery of a breeding colony of the endangered Finn’s Weaver, which is endemic to the Brahmaputra flood plain. (Source: Wikimedia)

5. The survey prioritised 10 species that are either globally threatened or endemic to the Brahmaputra floodplains:

5. The national park authorities have been particularly excited by the discovery of a breeding colony of the endangered Finn’s Weaver, which is endemic to the Brahmaputra flood plain.

Post Read Questions

(1) With reference to India’s biodiversity, Ceylon frogmouth, Coppersmith barbet, Gray-chinned miniyet and White-throated redstart are (UPSC CSE, 2020)

(a) Birds

(b) Primates

(c) Reptiles

(d) Amphibians

(2) If you walk through countryside, you are likely to see some birds stalking alongside the cattle to seize the insects disturbed by their movement through grasses. Which of the following is/are such bird/birds? (UPSC CSE, 2014)

1. Painted Stork

2. Common Myna

3. Black-necked Crane

Select the correct answer using the code given below.

(a) 1 and 2

(b) 2 only

(c) 2 and 3

(d) 3 only

(Sources: Delhi Bird Atlas released on June 5,  First-ever grassland bird census : A must-know for UPSC exam, 

🚨 Click Here to read the UPSC Essentials magazine for May 2026. Share your views and suggestions in the comment box or at manas.srivastava@indianexpress.com🚨 

Subscribe to our UPSC newsletter. Stay updated with the latest UPSC articles by joining our Telegram channel – Indian Express UPSC Hub, and follow us on Instagram and X.