Marsh harriers are birds of prey, slightly bigger than ravens. Their heads are light-coloured and their bodies are predominantly or completely dark brown. The tail and, in part, wings (upper part of the wings, pinions) are ash-grey. The female bird, however, is totally dark brown, with only the top of their head being yellowish and the front edge of their wings being a lighter colour. The head of the marsh harrier is slightly lighter than the rest of the body, with a darker stripe around the eyes, which goes all the way to the neck. Their beak is yellow with a black tip. The throat is white. They build their nests in shallow water in a thicket of reeds or on dry land close to it. They use everything they can as building material, but mostly reed. The diameter of the nest is about a metre. Marsh harriers feed on all kinds of smaller rodents, Eurasian water shrews, duck-sized birds (mostly coots), bird chicks, and dead or sick fish floating on the surface of the water. They are excellent brood parasites. They are under protection (protection category III).