Brown Booby (Palau)

Sula leucogaster plotus




Boobies and Gannets (Sulidae)

Code 4


Code 6



Egg Color:

White to pale blue green, nest stained.

Number of Eggs:

1 - 3

Incubation Days:

40 - 47

Egg Incubator:

Both sexes

Nest Location:

On ground.

Nest Material:

Lined with grass, twigs, and debris.





Brown Booby (Palau): Large, black-brown seabird with white lower breast, belly, and wing linings. Sexes are similar. Medium, wedge-shaped, yellow to blue-gray bill. Blue to yellow facial skin. Long, narrow wings. Medium, wedge-shaped tail. Rather short, green-yellow legs and webbed feet. Plunge-dives for squid and fish just below the surface of the water. Rather quick, direct flight wing strong, steady wing beats.

Breeding and Nesting

Brown Booby (Palau): Two white-blue eggs are laid in a small mound made of broken shells and bits of vegetation. The nest is built on sandy or rocky ground on a small, isolated island. Incubation is carried out by both sexes for 42 days. This species typically nests in colonies.

Foraging and Feeding

Brown Booby (Palau): Feeds on small fish and squid. Forages by catching prey with bill. It can plunge dive to catch prey beneath the surface of oceanic waters or pick small fish off or near the surface of the water while flying just above the waves.


Brown Booby (Palau): Males produce low hisses; when aggressive, they produce a "chuff chuff" call. Females bark out a harsh "a-aarrk".

Similar Species

Brown morph Red-footed Booby has brown underparts, red feet, blue bill, bare skin at base of bill is red, and loral skin and eyering are blue.

The ventral part of the bird, or the area between the flanks on each side and the crissum and breast. Flight muscles are located between the belly and the breast.
The upper front part of a bird.
Parts of a Standing bird X
Head Feathers and Markings X
Parts of a Flying bird X