Tag Archives: Annual Bird Census.

Asia’s Shorebirds in Decline

Asia’s shorebirds in decline.


Common Redshanks roosting in the mangroves at Sungei Buloh during high tides. Fortunately their yearly numbers are still good.

Many of Asia’s migratory shorebirds are in decline. This is especially so for species migrating along the East Asian-Australasian Flyway, a major migratory corridor that includes Singapore. In the past decade, conservationists have identified the loss of coastal wetland habitats, especially in eastern Asia as among the key reasons driving the decline of migratory shorebirds. Illegal and unsustainable hunting across many parts of the region is also a major threat to migratory species.

The Nature Society (Singapore), in a recent interview on Channel News Asia’s “Singapore Today”, highlighted the decline of migratory shorebirds in Singapore, and more broadly in the region, based on the data collected from our bird censuses. Many viewers were alarmed by the absolute low numbers displayed for the Pacific Golden Plovers, Lesser Sand Plovers and Whimbrels.


The first Annual Bird Census was conducted by the Nature Society in March 1986 and had been faithfully carried out every March since. These single day counts from sites surveyed across Singapore provided us with 33 years of continuous data to determine the population trends of the country’s bird fauna.

Every year about 200 Whimbrels winter over at the Sungei Buloh Wetland Reserve


Together with the data from the Annual Waterbird Census, which started in 1990, the declining numbers of shorebirds such as the Pacific Golden Plovers, Marsh Sandpipers, Lesser Sand Plovers and Curlew Sandpipers are very clear to field observers. The loss of Serangoon Estuary and Senoko Wetlands is thought to have contributed to the decline of many shorebirds in Singapore. The Common Redshank has suffered less, and there are still good numbers annually, fortunately. 


Some Pacific Golden Plovers choose to roost inland or even on the fish farms at the Straits of Johor instead of the dry ponds at Sungei Buloh.

Their numbers were in the thousands in the 1990s, but the counts were in their tens or low hundreds during recent surveys.



Figure 1. Abundance trends for Pacific Golden Plover (1997-2017) based on Annual Bird Census data.


Figure 2. Abundance trends for Marsh Sandpiper (1997-2017) based on Annual Bird Census data.


Figure 3. Abundance trends for Common Redshanks (1997-2017) based on Annual Bird Census data.

Seletar Jetties

Rich coastal ecosytems like the Seletar mudflats must be conserved as they are irreplaceable.

So how can we stop or reverse these trends for our declining shorebirds? For a start we must continue work to conserve all our remaining wetlands like the rich coastal ecosystems at Mandai Mudflats, Seletar and Chek Java, which are highly irreplaceable. More importantly, we would need to continue with our long term monitoring work through bird censuses as tools to guide our ongoing and future conservation efforts.

Reference. NSS Bird Group Annual Bird Census 1995-2019.


By Lim Kim Chuah

Asian Openbill by Geoff Lim crop

Asian Openbill at SBWR, 24 March 2019, by Geoff Lim

The 2019 Annual Bird Census (ABC) was conducted on 24 March. Weather was generally fine at all the 17 sites covered. Another three sites on Ubin which were counted on 10 March as part of the Comprehensive Ubin Survey Monthly Survey were also added. This brings the number of sites counted to 20. The three sites counted on Ubin represented the sites which were traditionally counted during the ABC.

A total of 5,575 birds was counted, a 66% increase (2,207) compared to 2018. The number of species counted was 143 species, an increase compared to 137 species in 2018. The increases in both numbers and species counted in 2019 compared to 2018 could be due to the increase in the number of sites counted, 20 versus 17.

Some highlights from this year’s census include:

  • Asian Openbill – 1 at Buloh Route 1
  • Ashy Drongo – 1 at Telok Blangah
  • Black Bittern – 1 each at Bishan Park and Dairy Farm Nature Park
  • Black-browed Reed-Warbler – 1 at Kranji Marsh
  • Blue-rumped Parrot – 4 at Bukit Batok West (Sadly, this is likely to be the last year that this site will be covered as the place is currently being developed into the Tengah New Town)
  • Blue-winged Pitta – 1 at Lower Pierce and at Bukit Batok West and 3 at Poyan
  • Chestnut-bellied Malkoha – 1 at Poyan
  • Chestnut-winged Cuckoo – 1 at Halus
  • Cinnamon Bittern – 1 at Buloh Route 2 and 1 at Kranji Marsh
  • Crested Serpent Eagle – 1 at Malcolm Park
  • Dark-sided Flycatcher – 1 at Lower Pierce Reservoir
  • Great-billed Heron – 2 at Buloh Route 1, 1 at Buloh 2, 1 at Lower Seletar, 2 at Ubin East
  • Green Imperial Pigeon – 1 at Pasir Ris Park
  • Large Hawk Cuckoo – 1 at Pasir Ris Park
  • Lesser Adjutant – 2 at Buloh Route 1 and 1 at Kranji Marsh
  • Lesser Whistling Duck – 11 at Buloh Route 2
  • Little Grebe – 2 at Lorong Halus and 1 at Ubin East
  • Oriental Pratincole – 2 at Ubin West
  • Pallas’s Grasshopper Warbler – 1 at Kranji Marsh
  • Straw-headed Bulbul – 46 counted at 8 locations with most of them from Ubin
  • Violet Cuckoo – 2 at Poyan
  • Watercock – 1 at Kranji Marsh

Despite the increase in number of birds counted this year compared to 2018, the total is still below the last 10 years’ average of 7,356. This could be attributed to the lesser number of sites counted due largely to the lack of manpower which meant some key sites like Sungei Mandai had to be left out in 2019.


Chart below shows the total number of birds and species counted from 2010-19:


Chinese Garden turned out to be the site with the highest number of birds counted (432). And Kranji Marsh remained the site with the highest number of species counted (73).

Chart below shows the number of birds counted at each site:


Chart below shows the number of species counted at each site:


And again, it was not surprising that our ubiquitous Javan Myna is the most numerous birds counted, reclaiming its position from the Asian Glossy Starling which it relinquished to in 2018.


NSS Bird Group would like to thank the following volunteers for participating and helping with the census. Without their support, we would not have been able to continue to monitor the state of the birdlife here in Singapore all these years.

Lee Ee Ling, KP Teh, Alfred Chia, Veronica Foo, Wing Chong, John Spencer, Keita Sin, Danny Lau, Nessie Khoo, Alvin Seng, Terry and Jane Heppell, Francis Chia, Betty Shaw, Steven Shields, Alan Owyong, Con Foley, Yan Jiejun, Tan Kok Hui, Eunice Kong, Lee Bee Yong, Milton Tan, Beh Swee Hua, John Marriott, Woo Lai Choo, Cheng Li Ai, Pary Sivaraman, Arasu Sivaraman, Gahyatree Arasu, Lena Chow, Kong Lai Peng, Anandaraman Sivakumar, Patricia Lorenz, Jean-Marc Chavatte, Yong Jun Zer, Lim Jia Xuan and Lim Li Fang.