I was inspired by an image I saw on 365 by Richard Sayer, of a blue tit entering a feeder to get a full nut. I wondered if they would do the same thing here. I removed the top of the feeder but birds continued to peck through the cage, shortly the blue tits started to enter the cage to grab a whole nut and continue to do so even when the nut level gets quite low.
Well done Lee - now after several weeks the Great Tits and the Green Finches will lean into the feeder to grab a whole nut but it's only the agile little Bue Tits who will dive down to the bottom, grab a nut and then turn round completely to climb out again... and they do this incredibly quickly.