Bitterns are known for their loud "booming" call, produced by the males ... and conservation site teams monitor numbers by ...

Bittern numbers have increased by a fifth in the last year, the RSPB said Conservationists are celebrating a record year for bitterns ... for their loud "booming" call, produced by the males ...

The males produce a loud “booming" call when trying to attract a mate ... the importance of thriving wetlands with high densities of fish as crucial for bittern recovery. Volunteers and conservation ...