י גיבתון שלג ( a496

Snow Bunting
Snow Bunting
Snow Bunting








Plectrophenax nivalis
Plectrophenax nivalis
Plectrophenax nivalis


:גיבתון שלג
. גבתון גדול, גודלו 14-18 ס"מ ומשקלו 18-56 ג
. בלבוש הקיץ ראשו לבן, גבו שחור וכתם לבן בכנפו
. הנקבה, קודקודה, לחייה וצידי החזה מנומרים באפור
, בסתיו המופעים דומים.צידי החזה, הלחי
. כיפת הראש העורף והכתף בעלי גוון חום צהבהב נוטה לגוון החלודה
. בית חיותו נוף אלפיני. אזורי הרים סלעיים חשופים ללא עצים וצמחים
. סלעים ימיים ובקרבת אדם. מגובה פני הים עד לרום של 2300 מ
. ניזון בעיקר מזרעים שונים. הצעירים ניזונים רק מחסרי חוליות
. האוכלוסייה נודדת ברובה כשהזכרים נודדים 3 שבועות קודם מהנקבות
. בארץ נתגלה באקראי. נצפה במשך חודשיים עד שנטרף על ידי בז מצוי ב2014
... תימה מהו אמר לא ידע האי גברא דעוף טהור חייב לשולחי ...חולין קמא, ע"ב
Subspecies and Distribution.
P.n.nivalis/ N North Americca. Alaska, Canada, Greenland. P.n.insulaeIceland N Scotland.
P.n.vlasowae NE European Russia to C & E Asia. Frrom Caspian region to Mongolia, Transbaikalia, China, Japan and Korea. P.n.townsendiCommander Is, and Aleutian Is. Middle East. םםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםם םםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםםם
Descriptive notes.
A large emberizid. 14-18 cm, 18-56 g. With large conical bill and relatively short, notched tail. Male nominate race breeding has head, neck and entire under parts white, sometimes some black in crown. upperparts black, back sometimes mottled with brown, rump and shorter uppertaiI-coverts white, central rump sometimes mottled with black. Three outer pairs of rectrices white, thinly tipped black on outer web, three central pairs black with pale fringes; most of upperwing white, alula feathers black, primaries black with white bases, tertials black; iris dark brown: bill black, legs dark grey or black. Male non breeding has white areas washed with rusty brown particularly on nape, crown, ear-coverts and breast. Black feathers on back edged with frosty brown, bill yellowish. Breeding plumage acquired mostly through wear (although has limited pre-breeding moult). Female is smaller than male. In breed¬ing plumage has crown and rear of head usually more dusky than male, upperparts duller, often brownish. Dark feathers of upperparts with pale fringes and somewhat less white in wing. in very worn plumage resembles male.
Habitat. It reeless. uncultivated barren rocky terrain, often near snow, also sea cliffs. Often nests near or even in human settlements. In winter found in open fields, shingle beaches, salt marshes, sand duties, and stubble fields. From sea-level to 2300 m.
Food and Feeding.
Mainly seeds. But in breeding season also small arthropods. Young fed only with invertebrates, including variety of insects, also worms and spiders.
Walks, runs, and occasionally hops, will sally to catch flying insects. Sometimes perches in trees or on fences, and burrows into snow. In non-breeding season in flocks of tens to hundreds of individuals, but also singly and in twos and threes. Sometimes associ¬ates with other species, Horned Lark Erentophila alpestris.
Breeding.
Pair formation by late May in Greenland. Breeds from mid-May through Jul in Iceland. begins breeding in late May in Scotland, and pair formation in early Jun in Canada. Timing of arrival pairing and egg-laying dependent on weather conditions, and sometimes signifi¬cantly later in years with cold spring. may be double-brooded (varies geographically and from year to year), but mostly single-brooded in Arctic. Monogamous. Males arrive in breeding area at; much as 34 weeks before females, remain in flocks for two weeks before breaking out into territorial defence. Male has elaborate aerial display during which he rises to 15 m, then glides into wind with wings held in a "V- above body while singing.
Both sexes search for nest-site, only female builds nest, a thick cup of dry grass and moss, lined with finer grasses, fur and feathers. commonly those of ptarmigan , placed in variety or places, commonly in crevice or crag in rocks, but will also use artificial site such as building, tin can, grave, human skull and the like. Clutch 2¬8 eggs, most commonly 5, white to pale green or pale blue and marked with brownish purplish or reddish spots, scrawls and splotches (usually concentrated at large end). Incubation by female. Often fed on nest by male, period 10-15 days, most commonly 12-13 days, nestling period 13 days.
Movements.
Most populations migratory. Females move farther S than males. Males move N in spring considerably (3-6 weeks) earlier than females, older males earlier than young males. Much of the migration not well known.
Status and Conservation.
Not globally threatened. Has spread west into Fenno-Scandia and nort-east into Kola peninsula.
Israel.
In Israel, accidental. It was observed on the Acre coast. After two months devoured by Kestrel. (2014)

P.n.insulae

P.n.bivalis

P.n.bivalis


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