The Eurasian Bittern (Botaurus stellaris) is a large, secretive wading bird found throughout much of Europe and Asia, as well parts of Africa. This species is also known as the Great Bittern. Eurasian Bitterns live in densely vegetated wetlands such as reedbeds and can be difficult to see.

What does a Eurasian Bittern sound like? Eurasian Bitterns make deep, resonant booming calls which can be heard for several kilometres. Listening for these calls is often the best way to detect the presence of this species during their breeding season.  This male ‘song’ is usually a series of 2-6 foghorn-like booms, preceded by a few softer pumping, gulping notes. The bittern creates this sound by inflating its oesopagus which acts as a resonance chamber. The function of this sound is to advertise his presence to female bitterns and also as a territorial call. Other sounds made by the Eurasian Bittern include bill snaps and a harsh ‘kau’ call, often given when in flight or alarmed.