White-headed dipper

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White-headed dipper
Bald dipper

Bald dipper

Systematics
Order : Passerines (Passeriformes)
Subordination : Songbirds (passeri)
Superfamily : Muscicapoidea
Family : Cinclidae
Genre : Dipper ( Cinclus )
Type : White-headed dipper
Scientific name
Cinclus leucocephalus
Tschudi , 1844

The bald dippers ( Cinclus leucocephalus ) is a bird art of the genus of dippers ( Cinclus ) from the family Cinclidae. It is much smaller than the Palearctic species in this family. It occurs in the Andes from Venezuela to Bolivia . She is a resident .

Like all representatives of the Cinclidae , this species is closely tied to life along fast-flowing, oxygen-rich waters, where it feeds primarily on aquatic invertebrates . This species probably doesn't dive. Three subspecies are described. The IUCN classifies the population of the species as not endangered.

description

White-headed dipper

With a body length of around 15 centimeters, the white-headed dipper is about the size of a greenfinch . However, it has the typical dipper shape with a large head, slightly detached from the body, a rounded body, a very short, often stilted tail and relatively long legs.

White-headed dippers are quite variable in their color, especially the extent of the white plumage is very different. In general, the crown and neck, and occasionally parts of the back, are white with black inclusions and dashes of varying degrees. The neck feathers are often slightly elongated. The throat and chest are white. A black band stretches from the beak over the eyes to the neck. The white breast flap merges with white-gray spotted transitions into the more or less pure black body plumage. The iris is brown, the beak is black, and the legs are lead gray.

Young birds are pale black-gray in color; the white parts of the plumage of the adults are rather washed out white-gray. The feathers of the back and flank plumage show lighter ends, so that the impression of scaling is created.

voice

The main call is a sharp ziiit-ziiit . The singing is a loud, but often drowned out by the rush of water, melodious chirping with embedded whistles, trills and squashed-sounding sounds.

distribution and habitat

Distribution area of ​​the white-headed dipper

The white-headed dipper occurs in a narrow belt in the Andes and their foothills from Venezuela southwards via Colombia , Ecuador and Peru to Bolivia.

In this distribution area, it inhabits habitats along fast flowing, clear mountain streams and rivers, especially at altitudes of 1000 meters to 4000 meters. Occasionally it also rises to the limit of the páramo . The white-headed dipper is largely a resident bird.

Food and subsistence

The food composition and the food acquisition of this species are only insufficiently researched. Like all dippers, the white-headed dipper feeds exclusively on carnivore . The main components of their diet are aquatic invertebrates and those small animals that can be found on rocks washed around, along streams or rivers, in shallow water and in bank vegetation.

In contrast to the Eurasian and North American species of dipper, the white-headed dipper seems, at least as far as has been observed so far, neither to dive nor to swim. It picks its prey on rocks and stones, wading at the edges of the water for food or reading insects from the leaves of the bank vegetation.

Breeding biology

There is very little information available on reproduction. Two nests have been described from Ecuador: one lay in a crevice behind a small waterfall, the other in a similar position in the immediate vicinity of a waterfall. They measured about 25 centimeters in diameter and consisted of an outer layer, mainly made up of moss, and an inner nesting cavity made of dry leaves, pieces of bark, but also plastic material. In large parts of the distribution area it can be confused with nests of the thick-billed bushhammer ( Lysurus castaneiceps ), which occurs regionally sympatric with the white-headed dipper.

The clutch usually appears to consist of two, probably white eggs. The breeding period should be between March and November. Clutches were found in Venezuela in March and in Bolivia in November. Fledgling young birds were observed in May in Bolivia, in July in Peru and in October in Colombia. No information is available about the duration of the breeding or nestling period.

Systematics

The white-headed dipper is one of the five species in the genus Cinclus within the family Cinclidae; Occasionally this is also understood as a subfamily (Cinclinae) of the flycatcher (Muscicapidae). Two species are in Eurasia, one is in North America and two are native to South America. The relationship of the family is the subject of research. In the past, due to morphological and behavioral similarities, they were placed near the wrens (Troglodytidae), today they are more likely to be more closely related to the thrushes (Turdidae) and mockingbirds (Mimidae).

Three well-differentiated subspecies are recognized:

  • Cinclus leucocephalus leucocephalus Tschudi , 1844 - The nominate form is common in the Andes of Bolivia and Peru. Her breast is bright white, and the crown and neck plumage is only streaked with black stripes. The rest of the plumage is uniformly deep black.
  • C. l. leuconotus P. L. Sclater , 1858 - This subspecies found in the north of the distribution area, ie in Venezuela, Colombia and Ecuador, differs greatly from the nominate form: the pure white plumage parts extend to the belly; also the plumage in the rump area is not pure black, but clearly flocked whitish. The white head plumage is strongly dashed in black, the white parts continue to the middle back. The black rump plumage appears finely lined with whitish tones.
  • C. l. rivularis Bangs , 1899 - This subspecies is only found in a small, isolated area in northern Colombia in the Santa Marta Mountains . The dark parts of the plumage are not pure black, but brown-black; the throat, which is pure white in the other species, is markedly blackish dashed.

Inventory and inventory development

There are no current inventory figures or assessments of inventory development. According to the IUCN , the species is currently not endangered. In large parts of its distribution area, the white-headed dipper seems to be not uncommon. Apparently, however, it is very sensitive to changes in the environment, especially water pollution. For this reason, it has disappeared from some breeding grounds in the area of Quito in recent years .

Individual evidence

  1. ↑ data sheet Birdlife intern. Eng
  2. ^ Brewer, 2001, p. 206.
  3. ^ Brewer, 2001, p. 206.
  4. ↑ Greeney, 2008, p. 52.
  5. ^ Brewer, 2001, p. 206.
  6. ^ Brewer, 2001, p. 19.
  7. ↑ Johann Jakob von Tschudi, p. 279.
  8. ^ Philip Lutley Sclater, p. 274.
  9. ^ Outram Bangs, p. 105.
  10. ^ Brewer, 2001, p. 206.

literature

  • David Brewer, Barry Kent MacKay: Wrens, Dippers and Thrashers. Yale University Press, New Haven / London 2001, ISBN 0-300-09059-5 , p. 19; 62-63; and 205-206.
  • Harold F. Greeney : Observations on the nesting of White-capped Dipper (Cinclus leucocephalus) in Ecuador. In: Boletín SAO. Volume 18, No. 2, pp. 49–53 ( PDF file; full text; English / Spanish ).
  • Johann Jakob von Tschudi: Avium conspectus quae in Republica Peruana repiuntur et pleraque observatae vel collectae sunt in itinere . In: Archives for Natural History . tape 10 , no. 1 , 1844, pp. 262-317 ( online [accessed March 16, 2014]).
  • Philip Lutley Sclater: Description of eleven new species of birds from tropical America . In: Proceedings of the Zoological Society of London . tape 25 , no. 344 , 1857, pp. 271-277 ( online [accessed March 16, 2014]).
  • Outram Bangs: On some new or rare birds from the Sierra Nevada de Santa Marta, Colombia . In: Proceedings of the Biological Society of Washington . tape 13 , 1899, pp. 91-108 ( online [accessed March 16, 2014]).

Web links

Commons : Bald Dipper ( Cinclus leucocephalus )  - Collection of images, videos and audio files