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Sunday 19 November 2017

Horned grebe or Slavonian grebe - Podiceps auritus (Linnaeus, 1758) Χειμωνοβουτηχτάρι, Χειμωνοβούττης - Cyprus

3rd Cyprus Record found by Alison McArthur.
Σπάνιος επισκέπτης της Κύπρου με τελευταία καταγραφή το 1958  
3 αναφορά για την Κύπρο 

Photos at Kouklia 19/11/2017 by George Konstantinou
The horned grebe or Slavonian grebe (Podiceps auritus) is a relatively small waterbird in the family Podicipedidae. There are two known subspecies; (P. a. auritus), which breeds in Eurasia, and (P. a. cornutus), which breeds in North America. In Eurasia, the subspecies is distributed over most of northern Europe and Asia, breeding from Greenland to western China. The North American subspecies spans most of Canada and some of the United States. Both subspecies appear physically similar and get their name from large patches of yellowish feathers, called “horns”, located behind the eyes that can raise and lower at will.

Birders can easily recognize the Horned Grebe by its red-and-black alternate (breeding) plumage, its black-and-white basic (non-breeding) plumage and its characteristic “horns”. This small grebe is 31–38 cm long, has a wingspan 55–74 cm wide and weighs 300-570 g. It has a moderately long neck, flat forehead and a rear crown of black feathers. Its beak is straight and pointy with a white tip. Both subspecies are physically similar except, P.a. auritius (Eurasia) appears darker than P.a.cornutus (North America), which has light grey feathers on its back inconspicuous or absent in P.a.auritius.The Horned Grebe is often confused with the Black-necked grebe, which is similar in size and colouring but differentiates by a steeper forehead, a more slender bill and a fluffier rump.

The alternate (breeding) plumage of the Horned Grebe has bright erectable “horns”, black fan-shaped cheek feathers and an overall red-and-black colour. The neck, flanks, lores and upper-chest are chestnut brown, while the crown and back are black. The belly is a dull white. Males are slightly larger and brighter than females but are generally indistinguishable.

The basic (non-breeding) plumage is overall black and white. The neck, chest and cheeks are white, while the back and crown are a dull black-grey. The border between the crown and the cheeks extend in a straight line behind the eyes. The basic plumage does not have “horns”.


Juveniles appear similar to a non-breeding adult except they are a slightly duller shade of white and their back is tinged with brown. The line separating the cheeks and crown is less distinct and their beak is paler. The chicks are fluffy, with a dull grey back, a white belly and interesting black-and-white facial stripping.

The Horned Grebe is distributed in Eurasia and North America. In Eurasia, it breeds in a few isolated locations in Greendland (uncommon), Iceland, Scotland and northwestern Norway, while extensively from southeastern Norway to western China. It winters along the coasts of Iceland, Norway and the British Isles down towards the Mediterranean, the Black Sea and the Caspian Sea. In eastern Asia, the Horned Grebe winters along the coasts of China, Korea and Japan.

In North America, it is restricted to northwestern region of the continent, with 92% of its distribution located in Canada. The total North American range spans from south-central Alaska to northwestern Ontario. It breeds as far north as the Yukon and southern Nunavut to northwestern states, from Washington to Minnesota. Additionally, there is small population who breed annually on the Magdalene Islands of Quebec. Its wintering range is also primarily coastal from southern Alaska down to the northern Gulf of California. Its eastern overwintering range is from southern Nova Scotia, down to the Florida Keys and sometimes west to Texas.

Horned Grebes breed primarily in temperate zones, including prairies and parklands, but are also seen in boreal and subarctic regions. They breed in small to moderately sized (0.5-10 ha) shallow freshwater ponds, marshes and shallow bays on lake edges with beds of emergent vegetation. They prefer areas with sedges, rushes, and cattails along with large areas of open water. This habitat provides a suitable site for nest material, anchorage, concealment and protection for young.


Chicks swimming alongside adult in alternate plumage
During migration, they will stop along lakes, rivers and marshes. Following migration, they winter in marine environments of estuaries and bays or inland on large lakes, although in Norway, large concentrations congregate on inland lakes

Horned Grebes dive underwater using their large feet for agile manoeuvrability to feed on aquatic arthropods, fish and crustaceans. Otherwise will catch airborne insects at water surface. Underwater they swallow or capture large prey remerging at the surface to manipulate the fish headfirst. They usually feed solitarily or in small groups up to 5 individuals. During the summer, aquatic and airborne arthropods are preferred, whereas winter selection favours fish and crustaceans.

The Horned Grebe has a unique adaptation for swallowing fish whole. They will eat their own feathers from a young age, so their stomach has a matted plug that functions as a filter to hold fish bones until digestion.
From https://en.wikipedia.org/wiki/Horned_grebe





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