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 | nigricollis | |
| Classification | Brehm, 1831 | |
| Common name | black-necked grebe | |
| Size | 28 - 34 centimeters | |
| Wing Span | 56 - 60 centimeters | |
| Male weight | 250 - 350 grams | |
| Female weight | 250 - 350 grams |
| Geographic Range | North America, South America, Asia, Europe, Central Africa. |
| Physical Characteristics | the male and the female look like each other. The young have a black head, a black neck, and a black upper part of the neck, with a short crest. A bunch of long and narrow golden yellow -orange feathers spreads from behind the eyes and cover the sides of the head. Its flanks are usually nut-brown. Males are generally the most colourful. The iris is scarlet, the ocular ring is orange, and the beak and almost the whole paws are black while the internal surface of the lobes of the paws is light blue. The beak is long and thin and slightly bended up. Unripe individuals look much like adults during wintertime. In winter both the head and the sides of the head of the adults are black, the back part of the neck and the back are dark grey, except for the secondary feathers, which are almost entirely white and can be seen during the flight. The throat and the area behind the cheeks and the ears are white-greyish. The front of the neck, the sides of the breast and flanks are light grey. |
| Call | it is usually quiet, but during the mating season it gives a cry similar to the croacking of a frog. |
| Behaviour | it is an aquatic bird, with no tail. It spends most of daytime in the water, swimming and plunging to hunt amphibians, crustaceans, small fishes and molluscs or pecking away at the water surface to look for insects. When it plunges it hides its body in the water while its beak stays outside. They are very gregarious birds: when it's time for nesting they form very numerous and noisy groups, but also in winter they gather in big flocks to migrate. |
| Habitat | it is found in sheets of shallow water but rich with vegetation, lagoons, lakes, ponds. During winter it moves towards littorals, while in summer it prefers the hinterland. |
| Flight | during the flight paws are dragged behind the body in a clumsy way. Secondary feathers are white and visible during the flight. |
| Food habits | insects, small fishes, crustaceans, amphibians, molluscs. It often swallows its own feathers to protect the stomach and the intestine from the sharp fish-bones that can be ingested. The swallowed feathers delay the passing of the food through the digestive tract so that the time necessary for a complete absorption of nutritional substances is increased. |
| Migration | the reproduction areas are scattered in all Europe (Ireland, Finland, Sicily) and in Algeria and Morocco too. In Italy it is migratory and regularly wintering, moreover it is irregularly nesting. The individuals wintering or crossing Italy probably come from Central and Eastern Europe. |
| Nidification | it nests in the marshy and shallow water zones of lakes and ponds. It builds a floating nest anchored to nearby plants. The top of the nest extends little over water surface. The female lays from three to five white-brownish and brown spotted eggs. Parents share duties during incubation period, which lasts about 21 days, and breed the chicks together. Initially the chicks are carried on the back of the adults, afterwards they begin to follow parents for at least a month and a half before becoming completely independent. In October, the young leave the nest and gather with the adults in big groups to spend winter in the same place. It nests in dense colonies. |
| Status in the lagoon | it has been observed most of all in the open lagoon. There are just few of them along littorals and in fish farms. |
| Sources | |
| References | INBio - Instituto Nacional de Biodiversidad
- Costa Rica Canada's AquaticEnvironment eNature.com - Nature and wildlife field guide database www.oiseaux-nature.com Lone Pine guide to Birds of the Rocky Mountains 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.inbio.ac.cr/en/default.html http://www.aquatic.uoguelph.ca/ http://www.enature.com/ http://207.34.92.247/birdsite/ |
| Source of the photo | http://www.execpc.com/~mcphoto/ |
| Source of the call | http://www.cserkesz.hu/~szazs/madarhang/ |
| Source of the video | http://www.hbw.com/ibc/ |
Podiceps
nigricollis
