The birds were keeping their heads low. I can't say I blamed them. I was eventually rewarded with a (very distant) view of a short-eared owl on the hunt. It was the long, flappy wings that gave it away. Other than that, I only spotted a few gulls and a couple of grey herons. I'm guessing there were also little egrets about, but they will have been uncharacteristically camouflaged.
More photos here.