This swampy habitat is known for its riches and variety of birdlife. Because of its importance for the preservation of biodiversity, it is protected as an ornithological reserve. In Kolan mud and in the closer surroundings, 163 bird species have been noticed, 66 of which are nesting birds. Many bird species are looking for a shelter at the time of their movement and wintering in reeds. Some reside on the neighbouring meadows, and some nest in the nearby brook, while they come to the mud to feed on the many fish.