| י 8 ) טבלן בינוני | |||||||||||||||||||||||||||||||||||||||||||||||||
:טבלן בינוני | , קטן מהטבלן לבן הלחיים ושונה ממנו בלבושו בתקופת החיזור . בצוארו השחור ובציציות אזניו הנוטות מטה . בחורף צבע קדקודו השחור משתנה בהדרגה והופך לבן . חלקו התחתון של מקורו דק בקצהו דבר הגורם לו להראות כנוטה כלפי מעלה . בארץ חורף מצוי, המעדיף מאגרי מים גדולים
Subspecies and Distribution.
| P.n. nigricollis Europe to Asia. P.n. gurneyi S Africa. P.n. californicus Canada, USA, Mexico.
Descriptive notes.
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28-34 cm; 260-450 g.Only grebe with yellow tufts on head and rest of head and neck, Non-breeding adult can resemble P. taczanowskii but contrast less marked. Juvenile as non-breeding adult, but throat and foreneck dirty white, with dark collar at base or neck . Races separated on slight plumage differences. Habitat. genrally breeds on small, shallow, highly eutrophic water bodies, with lush vegetation and typically with stretches of open water; occupies ponds, fish ponds, sewage farms and quiet river backwaters, or areas of lakes and marshes with suetable conditions. rather erratic; readily moves into newly flooded areas, but also abandons many sites after few years. Outwith breeding season, moves to open standing, generally saline waters, or coastal waters, estuaries, bays, channels and arms of sea. Food and Feeding Especially during breeding season takes mostly insects, both adults and larvae, aquatic bugs, terrestrial and aquatic beetles, damselflies and dragonflies; also molouscs, crustaceans, amphivians (frogs and tadpoles) and small fish. Plant remains frequently recorded in stomachs, but probably ingested accidentally. Much food obtained by diving, with dives usually lasting under 30 seconds. frequently practices foliage- gleaning, and feeds more from water surface than most grebes, picking objects off surface, submerging head while swimming, or occasionally capturing flying insects. Breeding. Mainly Apr-Jul in Europe; all months in tropical Africa, with peaks usualy in or immediatly after long rains; peak laying Nov-Mar in Australasaia. Nest is platform of aquatic plants,either floating and anchored to vegetation or built from lake bottom. Usually 3-5 eggs; incubation 25-30 days. Sexual maturity at 2 years old. Movements. Mainly migratory and dispersive, though populations in S of range can be more or less sedentary. Highly gregarious on migration and in winter, forming concentrations of up to hundreds of thousands at certain sites in N America and Asia: at Great Salt Lake, Uta, and Mono Lake, California, sites for primary moult and migration staging; at Salton Sea, California, with 500.000 birds in winter; and in S Caspian Sea. Much movement apparently nocturnal, although diurnal migration also recorded in palearctic. Straggler to Hawaii; also to Azores, Madeira and Canaries. Status and Conservation. Not globally threatened.Widespread and locally abundant; probably most numerous of all grebes,In Europe has expanded N and W in last 100 yars, colonizing most of C and W of continent. Israel. In Israel subspecies P. n. nigricollis.. Uncommon passage migrant, non-breeding.
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