.ןטב-תנבל הלוס (33






Brown Booby
Brown Booby
Brown Booby




Sula leucogaster
Sula leucogaster
Sula leucogaster


לארשי

 .םינבלה ןטבהו הזחה דבלמ ההכ םוח העבצ ,היוצמה הלוסהמ הנטק :ןטב-תנבל הלוס
.תצקמב םיריהב לבא םירגובל םימוד םיריעצה
.םיגומלא ייא וא םיפושח םייאב םיקוצ לע תננקמ .ףוחל בורק הנוזמ תא הדצ ,םי הלודיג תיב
.ןוכיתה םיב יארקאב ,תליאב הרידנ תנמדזמ ץראב
.א'ע ג"ס ןילוח ... ןילכוא לוכאל וגהנש םוקמ ינטבו יאנקש ןיירש ינטבו ינבל ...
Subspecies and Distribution.
S. l. leucogaster Caribbean and tropical Atlantic.
S. l. plotus Red Sea and W Indian Ocean to C Pacific.
S. l. brewsteri NE tropical Pacific.
S. l. etesiaca CE Pacific.

Descriptive notes.

64-74 cm; 725-1500 g; wingspan 130-150 cm.
Bare part colour varies with race, especially in male; non-breeding male lacks blue on face.
Females average larger. Juvenile as adult, but duller brown above with dirty white underparts.
Race platus larger and more uniformly dark above than nominate; male etesiaca has pale greyish forecrown; most of head greyish white in male brewsteri.

Habitat

Strictly marine.
Feeds mostly on inshore waters. Not commonly seen sitting on water.
Nests on bare, rocky islands or coral atolls, preferably on cliffs or slopes, but also on flat ground, sometimes where vegetation dense; in some areas roosts in trees.

Food and Feeding

Mostly flying fish and squid; some halfbeak, mullet and anchovy; mean prey length 9,5 cm.May be less dependent on flying fish than other boobies.
Prey usually caught by plunge-diving, from low over water and at oblique angle, but height and angle both appear to be variable; commonly uses feet and wings for underwater propulsion, though this may not be efficient enough to catch live, mobile prey, also snatches prey off surface of water in flight. Sometimes kleptoparasitic, especially on S. dactylatra and even on frigatebirds in one study, most attacks on S. nebouxii carried out by females.
Feeds close inshore, sometimes in small groups, but generally more or less solitary.

Breeding.

Seasonal in some areas, but elsewhere breeding opportunistic or more or less continuous.
Usually nests on ground, bur often in midst of vegetation; colonies tend to be smaller than those of other sulids; nest is small depression in ground, sometimes lined with twigs or grass.
Normally 2 eggs, but brood reduced to 1 chick; incubation 43 days, chicks have whitish down; fledging 85-105 days.
Age of first breeding probably 2-3 years.
Annual mortality rate of adults 6%.

Movements.

Adults tend to stay more or less permanently around colony.
Young and non-breeders disperse widely, and some records of inter-colony movements.

Status and Conservation

Not globally threatened.
Possibly most numerous and widesread lpecies, but population often scatterd and thus difficult to estimate total numbers, must be several hundred thousand individuals, distributed over hundreds of small colonies.

Israel.

In Israel subspecies S. l. plotus. Regularly visitor mainly in Gulf Eilat, rarely in Mediterranean Sea.

S. l. leucogaster

S. l. plotus
(in Israel)

S. l. brewsteri
S. l. etesiaca

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