(Great) Bittern
Botaurus stellaris

Bitterns are members of the heron family and as such, they hunt fish, frogs and other animals in water. Bitterns are often quite shy and retiring, preferring to remain hidden in reed beds. Occasionally, icy conditions can force them out of cover. The males make a 'booming' call in mating season, likened to blowing across the top of a milk bottle.
 

  

1-2: Fanel, 27/12/2007.