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Rising sea levels spell danger for shorebirds such as oystercatcher

Research by James Cook University in Australia involving Radboud University scientists shows that rising sea levels will drastically reduce the number of shorebirds in Europe. The number of oystercatchers on three Waddeneilanden will decline an additional 56 to 79 percent over the next 100 years due to sea level rise.

Even in a low greenhouse emission scenario that limits global warming below two degrees, it was projected all three studied oystercatcher populations would be reduces by more than half. This is because the sites where the oystercatchers nests are already flooding due to sea level rise. 

Lead researcher Martijn van de Pol of James Cook University: 'Oystercatchers typically nest on the lower parts of the saltmarsh: these are overgrown areas of land directly bordering the sea. Historically, these nests would rarely get flooded, but now they do on a regular basis. As a result, there is fewer offspring being born and population numbers are dropping.' The oystercatchers' ability to adapt is not sufficient to cope with this rate of sea level rise.


The researchers analysed four decades of field data and saw that the quality of habitat for shorebirds is declining due to increased nest flooding. Ecologist Eelke Jongejans of Radboud University was involved in the study: ‘Thus far, scientists have typically assumed coastal wildlife will mainly be affected by sea level rise due to habitat loss, but our study shows that strong impacts already occur. Even before their habitat is drastically reduced.' Flooding washes away nests more often and in a few years oystercatchers will have even less room to build their nests. 

Gas extraction

The research also shows that gas extraction under the Waddenzee can worsen the consequences of sea level rise for birds. Jongejans: 'We saw in our models that the greatest impact of gas extraction only takes place after the extraction has stopped. So for oystercatchers, among others, it is important that no more gas is extracted from the Waddenzee.'

Literature reference

van de Pol, M., Bailey, L. D., Frauendorf, M., Allen, A. M., van der Sluijs, M., Hijner, N., Brouwer, L., de Kroon, H., Jongejans, E., & Ens, B. J. (2024). Sea-level rise causes shorebird population collapse before habitats drown. Nature Climate Change, 1–6. 

Contact information

For further information, please contact one of the researchers involved or team Science communication via +31 24 361 6000 or media [at] (media[at]ru[dot]nl).   

Sustainability, Nature