Filming a common kingfisher at Langford Lakes

Last week we popped back over to land ford lakes, as I had seem that a kingfisher has been seen at the new hide for a few days in a row! ( Of course not on the day I go to film it. )
So ended up getting a handful "cutaways" or shoots that will be used to go between full story based sequences.
Till I popped down to see my other half, who was take some shoots of the dragonflies, when some of the kind staff, let us know, that there was a kingfisher fishing on the other side of the lake ( very far away. )
So wanted to talk about some of the challenge that comes, when filming at 2,400mm.