This creature is not rare but quite asocial, misanthropic, and hidden. It usually walks gloomily in shallow water looking for fish, frogs, and other delicatessen. Bittern prefers overgrown marshes, so to meet and especially to see a bittern is not easy.
Before this time, I saw the bitters twice by the standard way – something brown behind bushes.
This time it has shown in all its glory.
More of the bittern: