DISSEMINATION
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DISSEMINATION |
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| Kingdom | Animalia | 
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| Phylum | Chordata | |
| Class | Aves | |
| Order | Podicipediformes | |
| Family | Podicipedidae | |
| Genus | Podiceps | |
| Species | cristatus | |
| Classification | Linnaeus, 1758 | |
| Common name | great crested grebe | |
| Size | 46 - 51 centimeters | |
| Wing Span | 85 - 90 centimeters | |
| Male weight | 750 - 1200 grams | |
| Female weight | 750 - 1200 grams |
| Geographic Range | Southern regions, Africa (South of the Sahara), Asia (South of Himalayas), Australia, New Zealand and near islands. |
| Physical Characteristics | it is the biggest grebe. It is easily recognizable by the tuft of black feathers it has on its head, and, in spring, by the red and black tufts of feathers adorning the sides of its head. It has a thin neck, which in the lower part is dull white, while in the upper part it is brown- grey. The back is grey-brown; the beak is long, sharpened, grey- pink, with a brown upper border. In winter the face is almost white and springtime dark face ornaments have disappeared. |
| Canto | it is very noisy, the chicks perform little persistent cries. |
| Behaviour | in order to hunt the fishes it feeds on it dives reaching even three metres depth: it can resist in the water up to a minute, swimming with its lobate paws. It can control its floating level swelling or squeezing its plumage. When it feels in danger it prefers to plunge in the water, re-emerging ten metres further, then it flies up. |
| Habitat | it is found in lakes and ponds, where banks are covered with beds of reeds and rushes with which it gets easily mingled thanks to the colour of its plumage. |
| Food habits | it feeds on small fishes, molluscs, water insects, frogs, tadpoles, seaweeds. |
| Migration | it is a short distance partially migratory species, sometimes resident. In Italy it is a localized wintering species, while it is widespread as migratory and wintering. The individuals that are present in winter come from Central and Northern Europe . |
| Nidification | the pair builds on the water a floating hurdle platform anchored to nearby plants or lying on the bottom. The female lays 3-5 whitish eggs between April and June, the incubation lasts about 28 days and it is carried out by both parents. The chicks can leave the nest just born: they swim and plunge, even if they are often carried by their parents in the back wing pockets; they become completely independent at the age of 2 or 3 months. |
| Status in the lagoon | it is well widespread as a wintering species, most of all in the open sheets of water; in a reduced number it can be found along littorals and in fish farms. The only area in which reproduction was verified is the lagoon of Caorle. |
| Sources | |
| References | La Riserva Tevere Farfa - Un'area umida di
importanza internazionale Oiseaux de France Atlante degli Uccelli Nidificanti in Provincia di Venezia - a cura di M. Bon, G. Cherubini, M. Semenzato, E. Stival - Provincia di Venezia, Assessorato Caccia e Pesca. I censimenti degli uccelli svernanti in Provincia di Venezia - a cura di M. Bon e G. Cherubini - Provincia di Venezia, Assessorato Caccia e Pesca. |
| Web References | http://www.mclink.it/n/tevere/riserva/riserva.htm www.oiseaux-nature.com http://www.oiseaux.net/oiseaux/ |
| Source of the photo | http://home.t-online.de/home/UMWELTBILD/ |
| Source of the call | http://aves.desdeinter.net/ |
| Source of the video | http://www.hbw.com/ibc/ |
Podiceps cristatus
