Rising sea levels danger to shorebirds

Oystercatchers will decline by 56 to 79 percent on three Wadden Islands over the next 100 years. This is according to results from James Cook University in Australia which continues on previous research by NIOO. 

'Half of this collapse will happen in the next 50 years with numbers already declining now due to sea level rise, and the rest in the 50 years after that' says lead researcher Martijn van de Pol from James Cook University, formerly at NIOO. Even in a low greenhouse gas scenario, where global warming is limited to less than two degrees, the oystercatcher populations are expected to decline by more than half. This is because the sites where oystercatchers nest are already flooding due to sea level rise.

Nesting behaviour when facing climate extremes

Van de Pol: 'Oystercatchers usually nest on the lower parts of the salt marsh: these are overgrown pieces of land directly bordering the sea. Historically, these nests would rarely get flooded, but they are now getting flooded more often due to sea level rise, causing fewer offspring being born and population numbers dropping'.

Previous NIOO research focused on ecological effects like these of climate extremes. For twenty years, nests of oystercatchers on Schiermonnikoog were monitored and showed that these birds do not adapt their behaviour to rising sea levels. The nests are still at the same height as before, even though there is now a greater risk of flooding. Take a look behind the scenes at how this research was conducted with Martijn van der Sluijs' oystercatcher vlogs (Dutch).