The largest of divers has a length of 51-60 cm and a wingspan of 85-90 cm. Weight: 750-1200 g. Dimorphism is seasonal and age. In their summer plumage Great Crested Grebes have long narrow necks that are white in front and dark brown behind. Two black tufts rise from their dark caps, and their white faces are lined with wide reddish brown wide cheek tufts. Their backs are dark brown, their flanks and are a lighter brown and they have white underparts. In flight they look slender, and white patches are visible on both the leading and trailing edges of their wing bases. Their legs are yellowish grey, toes are lobed. Bills are yellowish brown, and irises are red.
Juveniles generally resemble adults, except for their heads, which have black and white patterning and no crests. Their caps and the backs of their necks are dark, and they have a dark stripe above their eye and a second dark stripe below the eye which continues indistinctly onto the side of the throat. Their irises are orange. Great Crested Grebes’ winter plumage resembles their summer colouring, but they have no ear or cheek tufts.
Great Crested Grebes are very noisy birds. Breeding pairs perform a complex courtship display that includes a “penguin dance”, where the birds stand up erect from the water facing each other. Parents often carry their young fledglings on their backs or under their wings, even while diving.
Distribution and Habitat
In Europe it occurs everywhere except in northern Scandinavia. It inhabits also Australia, New Zealand and Equatorial Africa. Migrate in Western and Southern Europe and Western Africa.
For Bulgaria, the Great Crested Grebe is a breeding-passing, passing and wintering species. Incubating along the Danube and Black Sea coast, the Danube Plain, the Sofia Field, the Maritsa and Tundja Valleys.
It inhabits freshwater lakes, fishponds and dams. Prefers water reservoirs, ringed with a broad but not very dense band of cane or reed; in the winter – large freshwater lakes, dams, lagoons and shallow sea bays.
Great Crested Grebe feeds on fish, frogs, crustaceans, molluscs, tadpoles, water insects and their larvae, aquatic plants.
The Great Crested Grebe has one generation a year. The breeding area has an area of 350-500 sq. M. for single and 50-150 sq. M for colonial nesting. Breeds in the shallow sections of ponds near reed beds. The nest is a raft made of aquatic plants, algae and reeds sliding on the surface of the water, but usually attached to a group of aquatic plants. From April to July, the female bird puts 3-6 white eggs that change color in brown and thus become less noticeable. Both birds incubate, alternating every few hours. Hatching occurs after 28 days. The young are able to swim at once, but remain dependent on their parents for several weeks. In case of threat the little ones hide in the plumage of the female, which by diving avoids the danger.
Vulnerable. Protected of the BDA. A substantial part of the habitats are included in NATURA 2000 protected areas.