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.ןטק טגירפ (38 | ||||||||||
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,םירהוז קוריו לוגס ,לוחכ ינוג םע רוחש ועבצ .םיטגירפה ןיבמ ןטקה :ןטק טגירפ | ||||||||||
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Subspecies and Distribution.
F. a. iredalei W Indian Ocean. F. a. ariel C&E Indian, W & C Pacific Oceans. F. a. trinitatis S Atlantic. | ||||||||||
Descriptive notes.71-81 cm: male 625-875 g, female 760-955 g: wingspan 175-193 cm. Much the smallest species.Male unique, all-black, glossed blue/purple/green, with white axillary "spurs". Female has white upper breast and axillary "spurs", females average slightly larger. Complex series of immature plumages, with progressively decreasing amounts of russet on head and white on underbody. Races very similar, separated on wing and bill length. HabitatTropical and subtropical seas, breeding on small, remote islands, in mangroves or bushes/scrub . more prepared to use lower vegetation thanF. minor on Aldabra. and can even nest on ground.Feeds in adjoining ocean, usually in waters over 22'C in pelagic zone. Food and FeedingMostly fish. especially flying-fish Cvpseiurus, Exocoptus, Evolan-tia of 10-20 cm. and squid of 4-12 cm: also seabird eggs and chicks, carrion and fish scraps.Surface dipping main system for obtaining food: kleptoparasitism used mostly by females. Food preference surprisingly similar to that of Great Frigatebird. Breeding.Throughout much of year at different localities, some preference for laying in dry season. Probably biennial, when successful.Colonial, with sub-groups of up to 100 nests, often in mixed colonies alongside other species of Pelecanifonnes, sometimes with F. minor. Nest is stick platform, usually up to 15m up tree. One egg. Incubation c. 45 days. Chicks naked, grow white down, fledging 20-24 weeks. Movements.Sedentary, with dispersal of immatures and non-breeders throughout tropical seas, especially of Indian and Pacific Oceans. Results from ringing of some 13,000 juveniles in SC Pacific indicate that they follow prevailing winds W to Coral Sea, NE of Australia, before heading off N by New Guinea towards Philippines, with some reaching Japan; recent evidence suggests possible mixing with Australian birds, with some heading further W to Cocos (Keeling) Is.May be trying to colonize Christmas I, Indian Ocean. Vagrant to Japan, Siberia. NE USA and New Zealand. Status and ConservationNot globally threatend. World population probably several hundred thousand birds.Israel.In Israel subspecies F. a. ariel. very rare. Observed at Eilat. |
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