This blue tit appears to be trying to attack its own reflection seen in a shed window in Norwich.
The bird returns for a number of 'attacks' and appears to almost knock itself out on at least two occasions.
The clip was shared by user Tony Morter on our community website iwitness24.
Tony says: 'Here's a determined blue tit, tapping at his own reflection, on the garden shed windows!
'The attached plant guide wire, across the window frames, serves as a great perch to launch and re-launch the onslaught. Daily return visits have been ongoing for the past few days so his territorial 'adversary' has not given up yet!'
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