Great crested grebe

The great crested grebe (Podiceps cristatus) is a large and distinctive waterbird with a courtship ceremony that is well worth seeing. It was once almost extinct in the UK but is now no longer regarded as being in danger as a species.

Appearance

The bird is about 48 centimetres (19 inches) in length, with a long slender neck and a pink dagger-like bill. The underparts are mainly white with the upper part of the body being reddish-brown in summer and greyish in winter. The wings are dark grey throughout the year. The face is mostly white, but in summer the rear of the head is reddish–brown, getting darker towards the back. A black line runs from the bill to the eye, which is red. Males and females are identical in plumage and size.

The double crest, after which the bird is named, is dark grey and is raised as a plume during the courtship display. After the late summer moult, the crest almost disappears. These crests are what led to the great crested grebe being hunted in past times.

Behaviour

The great crested grebe is at home on the water, generally inland lakes, flooded gravel pits and reservoirs, and only occasionally on rivers. Preferably, the chosen patch of water is well supplied with reeds and/or sedges. However, they often winter on coasts and estuaries.

On land they are clumsy birds, their legs being set so far back on their bodies that walking is an effort for them. They are also infrequent fliers, preferring to dive rather than fly when in danger.

The great crested grebe has a varied range of calls that can be described as croaks, growls and snarls, particularly when breeding.

Great crested grebes feed mainly on fish, insect larvae, crustaceans, molluscs, tadpoles and frogs.

Breeding

Great crested grebes return to their breeding grounds in March or April, and courtship begins with a male and a female greeting each other by stretching their necks out across the water. They then swim towards each other, with crests erect and calling all the time, and embrace by rubbing necks. Like synchronized swimmers they dive together, but unlike their human counterparts they grab billfulls of weed from the bottom which they then display to each other, nodding their heads from side to side as they do so, rising out of the water as they tread with their feet.

This mutual display may constitute a “promise” to build a nest, as it is material from the lake bottom that comprises much of the material. In shallow water, the nest can be built from the bottom until it breaks the surface, or it can be free-floating among the reeds at the edge of the lake.

The clutch of eggs is three to six, with both partners incubating them for up to 27 days, although the female is seen on the nest more frequently than the male. When hatched, the chicks are carried on their parents’ backs, often hiding under the wings, although they are able to swim and dive for themselves from the start. The parent birds feed the young on molluscs and insects.

© John Welford