Can be heard year-round but most common form late-winter/early spring into early summer. Timing and repetitive nature of calling behaviour suggests these might involve mostly territorial flights.
Coots have two main call types but both can be very variable.
1 – wailing calls
These calls consist of short sequences of notes, some quite similar to day time calls. The exact shape of the notes can be very variable but the slightly halting, stuttered nature of the sequence is characteristic. Notes can be prolonged and have a slightly wailing or moaning quality, as in the second example below. The calls are usually readily identified from Moorhen, which are much sharper and more rapidly delivered.
2 – high squeaks
These call notes are scarce but possibly overlooked. Possible confusion with Kingfisher and some Common Sandpiper call notes.
Kingfisher (high calls)
Common Sandpiper (high calls)