The Spoon-billed Sandpiper is one the world’s rarest and most endangered waders. RSPB has been involved in the international effort to save it since 2010. Migrants Recovery programme Manager, Guy Anderson, reports on September fieldwork in eastern China, a hotspot for ‘spoonies’ along their 8,000km migration route.
Precious service stations for migratory waterbirds
“Thumpth……..Thumpth………Thumpth…….”
The ground shakes each time the pile driver pounds another steel shaft deep into the mud of what used to the be the Yellow Sea. Another port being built in eastern China. Although the claiming of new land from mudflats and saltmarshes has been - thankfully - largely halted in China, the development of areas previously snatched from the sea goes on apace. On the bunded, and yet to be developed, patch of new land next door, 5000 waders seek refuge from the advancing tide and congregate as a skittering carpet dotted across the flat ground. Not very long ago this was open mudflat, and a scattering of long dead cockle shells tells the story of what decades of land claims have done to food resources needed by migratory birds in the Yellow Sea. Just as the estuaries, mudflats and saltmarshes of the UK and north-western Europe provide vital service stations for migratory waterbirds travelling along the East Atlantic Flyway, so do the same habitats that remain in the Yellow Sea, for birds navigating the East Asian-Australasian Flyway.
Spoon-billed Sandpiper ‘Yellow LY’, flagged during our fieldwork in China in September 2024, and now contributing to the science estimating the world population of this Critically Endangered wader. Photo taken 5 October 2024 by © Jiang Yilei (used with their permission).
Finding spoonies in a haystack
The waders gathering in front of me seem oblivious to the bass-line racket of the pile drivers next door. On the other side of the seawall that surrounds this area, the tide is high, there is no feeding to be done for a few hours, and these birds have few other options for a safe roost site. These are becoming few and far between along this coast. To my European eyes, the familiar shapes of Dunlin, Sanderling and Grey Plovers cozy up to less familiar Red-necked Stints, Broad-billed Sandpipers, confusingly similar species of sandplovers. Hiding in their midst, a small pale grey shape flicks its head from side to side, keeping watch for danger, and in doing so reveals its identity – a Spoon-billed Sandpiper. Scouring the carpet of waders through my scope reveals another 2, maybe 3, ‘spoonies’ at most. They are always a challenge to pick out, especially when roosting with their bills unhelpfully tucked away. Sparrow-sized and never very bothered about keeping close company with their own kind. It feels like trying to find spoonies in a haystack.
How many Spoon-billed Sandpipers are there?
So why the search? Part of an international research team, I’m trying to find as many spoonies as possible to help us track their numbers. Even just counting them is not easy. Like most bird populations, they never all occur in one place at one time, and we have incomplete knowledge of where spoonies go, along their vast flyway between the Arctic and south-east Asia. So we can’t just rely on adding up the numbers seen at the places we do know. The only reliable way is to use mark-recapture methods. Mark a number of birds (in this case with individually-coded small plastic legs flags), let those birds mix into population and then look at the ratio between numbers of marked and unmarked birds we see in field. Using exactly this method, we’ve just published the latest estimate of the Spoon-billed Sandpiper world population size, and its population trend. Both make sobering reading. Around 400 breeding-age individuals likely left now, following a slight decline over the last 10 years. The better news is that back in 2010, the population decline was estimated at a shocking 26% per year. This was a fast track to extinction, and thankfully that rate of decline has levelled off, following a huge international conservation effort successfully tacking several known threats. But we are not seeing a recovery yet, and 400 adult birds is not many to work with.
Urgent need for science-led conservation action
RSPB volunteers, Nigel Clark and Ewan Weston, surveying mudflats for Spoon-billed Sandpipers, gathering data required for estimating population size, Jiangsu Province China, September 2024. (photo: Guy Anderson, RSPB)
The need for rapid, robust and imaginative science to help spoonie conservation has never been greater. We have already used satellite tags to reveal unknown sites along the flyway, and to show us when spoonies use these. It is essential to be able to understand what threats birds might face at the places they rely on, when they are there. In combination with remotely sensed environmental data, we have used satellite tracking to predict other flyway sites that might yet to prove important for spoonies – focussing future survey and conservation efforts.
Spoonies are important in their own right. They also act as a flagship species for a whole community of migratory waterbirds using the East Asian-Australasian Flyway – many of which are Globally Threatened or Near-Threatened as a result of population decline – caused by exactly the same threats and pressures that Spoonies have faced, and still face. There is still time to save the Spoon-billed Sandpiper, but the need for robust evidence and prioritised species action planning, leading to coordinated international action, has never been greater. By working with international partners, RSPB continues to make a significant contribution to the science and monitoring, international policy and advocacy, coastal wetland creation and management capacity, and species conservation action planning efforts, that this species, and indeed this whole flyway, so badly needs.
More waders have arrived on the dry mud in front of me. I re-focus my scope and keep looking.
References
Green, R. E., Leung, K. K. S., Clark, N. A., Anderson, G. Q. A., Brides, K., Chang, Q., Chowdhury, S. U., Clark, J. A., Foysal, M., Zöckler, C., Gerasimov, Y., Gale, G. A., Iakushev, N., Khamaye, J., Lappo, E., Melville, D. S., Tomkovich, P. S., Weston, E., Weston, J., & Yang, Z. (2024). New estimate of the trend in world population size of the Spoon-billed Sandpiper suggests continuing decline. Wader Study, 131(2). https://doi.org/10.18194/ws.00344
Acknowledgments
See Green et al. (2024) for the full and long list of individuals and organisations who contributed to this study - most of whose continued dedication and commitment going forward will be vital to improving our chances of saving this amazing little bird.