They seemed to be taking it in turns to grab the wire with their beaks or feet, and on several occasions appeared to copy the previous attempt. What was even more unusual was that this play involved two different species of bird, carrion crow and jackdaw.
I've seen carrion crows playing before, as here when one seemed to be having fun annoying a swan!
In this case the crow is using its intelligence to try to get some food away from a gull.