Can be heard throughout the year, but most active from early spring to mid summer. Many calls probably relate to territorial behaviour.
Moorhens has one predominant nocturnal flight call type, plus three other calls which are given more rarely in flight and also from the ground.
1 – kek-kek-kek sequence
By far the commonest is a burst of harsh kek notes, often in groups of three or four. These can be given as a single burst, as in the top example below, or repeated every few seconds. Some passes can be very prolonged with 20 or more sets of kek notes, possibly indicating the bird is circling and territorial. This call can be hard year-round. It might be mistaken for Little Owl and Tawny Owl. Notes in the middle of a sequence are usually higher than those at the beginning and end. In the Distance Call of Tawny Owl the notes usually descend in frequency through the series.
2 – kik sequence
Possibly a variant of the kek, the individual notes are shorted and don’t have the typical “staple” shape of kek notes.
3 – krrrk call
This call will be familiar to many from the daytime. It is also heard at night from stationary birds and may occasionally be heard from flying birds, but seems to be quite rare.
4 – kiddick call
Again, a common call from stationary birds, but possibly also given (rarely) in flight.