I've seen Malcolm around here recently, so ...

On Friday we spotted a group (around 6) of greenish birds walking up and
down the bark of a mature willow tree, presumably searching for insects.
Not tree creepers, not nuthatches.

They were greenish brown on the back, creamy on the tummy, perhaps with
some dark in the head region, noticeably larger than sparrows, rounded,
very bouncy, also flying across to land on the heads of some large
umbellifers. Very tit-like in behaviour, but bigger than tits.

Anyone any ideas?

Sorry about inadequacy of description, but my birdwatching is normally
limited to identifying what is emptying my birdfeeders with such
rapidity.
--
Kay