| .ליפט ןסמח (232 | ||||||||||
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.תוטלוב תויזכרמה ויתורבאו ךורא ובנז ,ולדוגב ינוניב ,רתויב חיכש ןסמח :ליפט ןסמח ,םדמדא ןווג םע ההכ םוח ,דיחא עבצ תולעב ףוגה תוצונ :ההכ ,עבצ יעפומ ינש ליפטה ןסמחל .הזחב רפרפא ספ םע ןבל ןוחגהו בהבהצ-ןבנבל ראוצה ,םימוח ףרועהו שארה תפיכ :ריהב .ומש ןאכמו ,םפרט תא דודשל ידכ םי תופוע תברקב ,בשע ילב וא םע תורדנוט ולודיג תיב .תויפחשו םיפחש לש תולודג תוקהל םהב שיש תורהנ יכפשב ףרוחב .תליא ץרפמו ןוכיתה םי ףוח דיל ,תוחפ יוצמ ףרוחו חיכש חרוא רבוע ץראב | ||||||||||
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Subspecies and Distribution.
Stercorarius parasiticus Circumpolar in coastal tundra. Winters in oceans of Southern Hemisphere. | ||||||||||
Descriptive notes.45 cm, 330-600 g, wingspan110-125 cm. medium sized Skua, whit two color morphs stricingly different:Pale morph, commoner further N and almost 100% of population above 75 latitude N, has cream underparts and hindneck, with straw yellow ear-coverts and side of neck, and may have a pale brown pectoralband. Pale morph is very variable and can be quite dusky. Dark morph, common at S end of breeding range, uniformly sooty brown, heterozygotes, often clled intermediates, are almost identical to dark morph, hut with paler cheeks and often slightlypaler belly. Habitat.Breeds on tundra or moorland or grassland, either in association with coastal seabird colonies where it can rob other species of food.In winter often aggregating at coastal sites such as estuaries frequented by large numbers of terns or small gulls. Food and FeedingIn tundra habitats, microtine rodents are often not a major prey item in contrast with Pomarine Skua, adult and fledgling passerines, wader chicks, bird's eggs, insects are all exploited.While breeding, will obtain most or all of food by kleptoparasetesm, especially stealing fish from Arctic Terns, Atlantic Puffins and Black-legged Guillemots. In winter and on migration, present species often associates with aggregations of terns or small gulls, and feeds mainly by kleptoparasitism. Breeding.May-Jun. Colonial at seabird sites or widely scattered over tundera. Territorial.Nest scrape unlined and inconspicuous. 2 eaggs, but only one laid by some inexperienced birds, incubation 26 days. Chick has dark brown down. Leaves nest 2 days after hatching. Sexual maturity at 3 years. Movements.Mainly transequatorial migrant, with very small numbers wintering in Northern Hemisphere.Leaves breeding areas in Aug, and moves slowly S down coasts associating with small gulls and terns during passage. Winters coastally, especially in Coral and Tasman Seas, and around Humboldt and Benguela Currents. Rapid northward migration in Apr. Status and Conservation.Not globally threatened. Total population estimated at 100.000 pairs.Israel.In Israel subspecies Stercorarius parasiticus. Uncommon migrant and winter visitor off Mediterranean coast, quite common spring migrant at Gulf of Eilat. |
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