| .הרוחש תימורמ(270 | ||||||||||
| ||||||||||
|
.ונבולב טלוב תשה תתו רופא הבנז ,ריהב רפרפא עבצב םיפנכה ,םירוחש הפוגו השאר ץיקב .החיכשו ההכ ,הנטק תימורמ :הרוחש תימורמ ,רורבב םוחתה ןבלה ףתכה םתכב תורחאה תוימורמהמ תלדבנ ,םינבל הנוחגו הינפ ףרוחב .תוהכ תומודא םילגרהו רוחש רוקמה .רתוי ההכ םבגש אלא םירגובל םימוד םיריעצה .תוחפ דדוקמה הבנזבו רוחשה רוקמב ,הזחה ידיצבש רוחשה םתכבו .תורהנ יכפשו םיפוח דיל הדידנה ןמזב .תוחלמו תוציב ,םימגא דיל היחמצ ירישע םירוזא הלודיג תיב .הלוחה תמי לש ינופצה הצקב הנניק רבעבש ץראה ןופצב רתויב הרידנ ץיק תרקבמו ,םיכומנה םירוזאו הלפשב הרידנ חרוא תרבוע ץראב 16 ,א"י ארקיו ... ףחשה תאו ... | ||||||||||
|
Subspecies and Distribution.
C. n. niger S scaninavia S to S Spain, and E through E Europe and W Asia. Winters in Africa. C. n. surinamensis S Mackenzie and C Manitoba S to California, and E to Great Lakes, NW Pennsylvania and NW New York. Winters in Central America and N South America. | ||||||||||
Descriptive notes.Distinctive small dark tern. 23-26 cm, 65 g, wingspan 55-65 cm. Head, neck and breast black, becoming more dark slaty grey on back and belly, with grey upperwing and tail. Vent and undertail coverts white, underwing grey, bill black and legs blackish-red.Shows slight sexual plumage dimorphism, probably the only tern to do so. breeding female greyer, with dull black on head restricted to crown. Race surinamensis smaller and darker. Habitat.Breeding on well vegetated inland lakes, peat bogs and marshes, sometimes on brackish marshes. Prefers sparse, open vegetation of bulrush and cattail and other emergents, or floating water-lilies.On passage occurs on coasts and estuaries, but also at virtually any wetland, including even small ponds and ditches. Food and FeedingAquatic insects, small fish, tadpoles, snails and frogs. In breeding season diet based on insects.Usually feeds by aerial hawking and contact-dipping, occasionally hover-dipping, and more rarely plunge-diving. May feed up to 5 km from colony. Migrants feed in estuarine and coastal habitats, and flocks coalesce over schools of predatory fish. In Mediterranean, reported feeding in flocks over dolphins and tuna. Breeding.May-Jun in North America and Europe. Most colonies fewer than 20 pairs up to 100. Usually nests over water, also muskrat houses, boards, or old grebe or coot nests. 2-3 eggs, incubation 20-23 days.Chick similar to C. leucopterus but paler, with dark chin and throat. Movements.Palearctic birds often disperse N after breeding, with sometimes very large concentrations in S North Sea. Migrates in huge numbers through Mediterranean, and also across N Africa, to main wintering grounds on coasts from Mauritania to Namibia, some reaching South Africa.North American birds migrate to both Pacific and Atlantic coasts, wintering from Mexico and Panama S to Peru, and from the Gulf Coast to N South America. Accidental in Chile and Argentina. Status and ConservationNot globaly threatened. world population 500.000 pairs.Israel.In Israel subspecies C. n. niger. Scarce passage migrant in low-lying across the country, very rare summer visitor in north. Former breed in Hula Valley. |
| |||||||||
| HOME | NEXT | |||||||||
