Bittern booming at RSPB Minsmere

Skip to 01:01 and 02:05 for the Booming. Heres a video of a male bittern fishing and booming at RSPB Minsmere. Filmed on the evening of the 11/04/11 from the Island mere hide. sorry its a little jumpy in places due to the fact the hide is pretty bouncy and the it was pretty crowded now due to the fact the bitterns booming call is technically a form of infa sound it does not register on computer speakers just headphones from what I can gather so sorry about that. the Booming call can be heard at 1:02 and 2:04