Peculiarities of colonial breeding of the Black-necked Grebe in forest-steppe zone of the South Urals. - Yu.G. Lamekhov. - Berkut. 16 (2). 2007. - P. 187-194.
Black-necked Grebe is a breeding species in the South Urals territory. Its arrival to the nesting area coincides to a great extend with water and air rising temperature. Black-necked Grebe builds its nests among the nests of Black-headed Gull. At first gull’s nests appear in the territory of the colony and then the nests of the Black-necked grebe. Such a succession of events brings about the formation of the colony centre. Outlying area is formed around the centre. Black-necked Grebe nests are located both in the centre and in the outlying area of the colony among Black-headed gull nests. The colony life is connected with the action peculiarities of Black-necked Grebe and Black-headed Gull. Gull secures the protection of the colony. Grebe leaves the colony in case of danger. Water and air temperature is higher and wind speed is lower in the centre of the territory of the colony. Black-necked Grebe builds its nests from vegetative organs of the plants. The nests within one colony differ in size. Grebe has a tendency to the increase of a nest size with the rise of a number of eggs in laying. Black-necked Grebe eggs in one nest differ in size and mass. Differences in eggs parameters in the nests in the centre and outlying area of the colony can have statistically reliable character. [Russian].
Key words: Black-necked Grebe, Podiceps nigricollis, ecology, phenology, nest, clutch size, egg.
Address: Yu.G. Lamekhov, P.O. Box 13243, Chelabinsk 454091, Russia; e-mail: dobry_bobr@mail.ru.