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.
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.