eurasian bittern outdoor in summer botaurus stellaris in danube delta biosphere reserve

eurasian bittern outdoor summer botaurus stellaris danube delta biosphere reserve romania wildlife wild great nature heron bird animal beak plumage water lake natural background reed brown adult wetland birdwatching flight portrait camouflage yellow marsh bill green winter closeup camouflaged ardeidae europe feathers reeds european black feather horizontal beautiful pond ornithology male little swamp