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![]() Titicacadykker, Rollandia microptera gjengir ikke kilde da det var virus på den siden... Titicacadykker, Rollandia microptera, er en dykker som finnes på høyfjellsplatået i Peru og Bolivia. Som navnet indikerer, finnes de fleste på Titicacasjøen. Uru Uru og Poopó samt Desaguaderoelven, og små innsjøer som er fobundet med Titicacasjøen i våte år, tjener som ekstra territorium. Tidligere var bestanden større og flere av innsjødistriktene, som f.eks. Umayo- og Arapa-sjøen, hadde øyensynlig - og kan fortsatt ha - permanente store kolonier. Fuglen blir noen ganger plasert i gruppen Podiceps eller en monotypic genus Centropelma. Dens lokale navn er 'zampullín de Titicaca'. Det er en mellomstor dykker, varierende fra 28-45 cm i hel lengde. Den veier opp til 600 g. Fargedrakten er meget karakteristisk og egenartet. Den eneste dykkeren som nogenlunde ligner er en som ikke er i slekt, gråstrupedykker, Podiceps grisegena, som heller ikke finnes i Syd-Amerika. Podilymbus podiceps Ringnebbdykker Pied-billed Grebe all three pictures very C © Jim Scarff ringnebbdykker, Podilymbus podiceps, fugleart i dykkerfamilien. En middels stor dykker, 3038 cm, grålig brun med lyst nebb med svart ringformet flekk. Utbredt fra Canada til Patagonia. Tilfeldig gjest i Europa, påtruffet to ganger i Norge per 2003 (Nordland og Rogaland). Store norske leksikon, snl.no, Per Ole Syvertsen, 2010-10-27, http://www.snl.no/ringnebbdykker Hvitøredykker, Rollandia rolland, White-tufted Grebe, ![]() © www.arthurgrosset.com Hvitøredykker, Rollandia rolland, er også en lappeand i Podicipedidae familien. Den finnes i Argentina, Bolivia, Brazil, Chile, Falkland Islands, Paraguay, Peru, og Uruguay. ![]() Juvenile © www.arthurgrosset.com Dens naturlige område er grunne innsjøer. ![]() © www.arthurgrosset.com Maoridykker, Poliocephalus rufopectus, New Zealand Dabchick/Grebe, Maoridykker er omtrent 29 cm lang. Det er en liten og mørk dykker. .Svartaktig hode med fine sølvaktige fjær. Blekt gult øye. Mørn nøttefarget forhals og bryst. Svart-brun overside. Blekere utenfor hekkesesongen. Population estimate 1,700 - 1,800. Population trend decreasing.
Range estimate (breeding/resident) 87,400 km2. Maoridykkeren er hjemmehørende på New Zealand. Den
gjenværende bestand er begrenset til Nord-øya med en
spredt dekning. Den liker seg i små ferskvannsdammer som f.eks. små
innsjøer i sanddyneområder, og i laguner og større
innlandssjøer med Trusler den er utsatt for er bl.a. vannkvalitet, tørking
av sanddyneområder, ødeleggelse av reirplasser, økt
vegetasjon, økt menneskelig aktivitet på vannveier,
og rotter og mus, spesielt under ruging. Den er den største Nord-Amerikanske dykker, 56-74 cm lang.
Den er svart og hvit, med en lang svaneliknende hals og røde
øyne. Svanedykkeren har svart merkering rundt øynene og et rett
grønn-gult nebb mens gulnebbdykkeren er hvit rundt øynene,
This bird dines by diving for carp, herring, mollusks, crabs, and salamanders. Western Grebe fossils from the Late Pleistocene of SW North America
were described as a distinct species (Miller 1911), but later ranked
as a paleosubspecies Aechmophorus occidentalis lucasi (Howard 1946).
More recent study found them to fall within the variation now known
to exist in today's birds (Jehl 1967, Storer 1989). Gulnebbdykker, Aechmophorus clarkii, Clark's Grebe ![]() Clark's Grebe, Aechmophorus clarkii, taken at Lake Merritt in Oakland, California. http://en.wikipedia.org/wiki/File:Clark%27s_grebe2.jpg Clark's Grebe (Aechmophorus clarkii) is a North American species in the grebe family. Until the 1980s, it was thought to be a pale morph of the Western Grebe, which it resembles in size, range, and behavior. Intermediates between the two species are known. The "Clark" of its common nameand its specific epithet "clarkii"honor John Henry Clark, a 19th-century American surveyor who was also a naturalist and collector.[2] The genus name Aechmophorus comes from the Ancient Greek words "aichme", meaning spear, and "phoros", meaning someone who bears things around; it refers to the bird's long, daggerlike beak. This species nests on large inland lakes in western North America
and migrates
to the Pacific coast in winter. It maintains local populations year-round
in California, Nevada, Arizona-(the Lower Colorado River Valley),
and central Mexico. It feeds by diving for carp, herring, mollusks,
crabs, and salamanders. It performs the same elaborate courtship display as the Western Grebe. A family in California, USA. Two chicks are riding on one of the parent's backClark's Grebe is black-and-white and has long slender neck. It ranges in size from 2229 inches (5674 cm). Among its distinguishing features is its bill, which is slightly upturned and bright yellow, whereas the Western Grebe's bill is straight and greenish-yellow. It shows white around its eyes, whereas black appears around the eyes of the Western Grebe. The downy young are white, not gray. Atitlandykker, Podilymbus gigas, Atitlán Grebe, extinct (1989) The Atitlán Grebe (Podilymbus gigas), also known as Giant Grebe, Giant Pied-billed Grebe, or Poc, is an extinct water bird, a relative of the Pied-billed Grebe. It was endemic at the Lago de Atitlán in Guatemala at an altitude of 1700 m asl. Thanks to the field work of the American ecologist Anne LaBastille, its decline is comprehensively known. LaBastille observed this species for a period of over 25 years. She has also written a book about this bird called Mama Poc. ![]() ![]() The Atitlán Grebe reached a length of about 4650 cm. The call and appearance were similar to the Pied-billed Grebe. The plumage was mainly dark brown with white-flecked flanks. The underparts were dark grey flecked with white. The head was almost black and the neck was flecked with dark brown in the spring and white in the winter. The legs were slaty grey. The bill had a bold black vertical band in the middle. The color of the bill varied from white in the spring to brown in other seasons. The irises were brown. It had small wings and was flightless.
The Atitlan Grebe, Podilymbus gigas, is known only from Lake Atitlán
in Guatemala. First described in 1929, P.gigas is essentially a
larger version of the Pied-billed Grebe, P.podiceps, with a few
minor color differences, such as a darker head, neck and belly.
Although P.gigas is almost twice as heavy as p.PODICEPS, THE TWO
SPECIES HAVE ROUGHTLY SIMILAR WING LENGTHS, AND p.GIGAS IS REPORTED
TO BE FLIGHTLESS. pRIOR TO 1965, the population of P.gigas on Lake
Atitlán was estimated to be about 200., but a decreaqse3
to 80 in 1965 placed the species in danger of exti9nction and loed
to vigoro9us conservation efforts to protect it. In 1975 the population
temporarily recovered to its historic level of 2000, but then plummjeted
to approxiamtely 50 greb3es by 1983. |