I've looked hard, very hard, but I've never seen a bittern, which is why I'm desperately trying to find time to get to our Rye Meads nature reserve just north of east London.
I'm not one of those who'll bear discomfort to see a particular bird, but for a bittern, I might defy the cold snap. Especially as it's the cold weather that's forcing these shy and well camoflaged birds out into the open where they can…