‘We’ve seen oiled birds’: fears for protected wetlands after Poole harbour spill

As the seasons turn, the wetlands are uniquely home to winter birds yet to depart and summer birds recently arriving. Photograph: Jamie Grierson/The Guardian

On the Arne peninsula in Dorset, the gnarled heather and gorse gives way to a soft sand beach gently lapped by the opaque waters of Poole harbour.

But as a flock of oystercatchers graces the skies above this globally significant ecological site, an unsettling anxiety pervades the otherwise tranquil idyll.