Cuckoos (Cuculus canorus) fighting

Taken at RSPB Lakenheath Fen.

This image has been published in the following:
Vol 337 of the journal Science on 3rd August 2012.
"Cuckoo" by Prof. Nick Davies FRS, ISBN: 9781408856567, published by Bloomsbury

This image has been accepted in the following exhibitions:
German International DVF-Photocup 2011 - Salon Hessen
German International DVF-Photocup 2011 - Salon Niedersachsen