Heron?

I'm fairly sure I spotted a heron yesterday, being chased by two crows. I thought it was a gull until I saw the legs stretched out behind it in flight. Having looked it up, I'm no longer sure, because all the pictures I can find are of fairly massive birds. The one I saw was gull size, albeit a very big gull.
I've finally found a picture that looks a bit more like it, so it could well have been a heron.

Bird feeder

We've just refilled our bird feeder (after weeks of guilt when our local robin kept coming and looking hopefully at the branch on which it used to hang) and we're now visited by a pair of coal tits. It took me a while to decide whether they were actually coal tits because blue tits look very similar. They tend to fly down, peck at the seeds while they hang on to the feeder (flapping desperately to keep their perch) and fly off quickly again.