Brown Booby is a widespread Booby species, with nesting colonies found on
islands throughout the tropical oceans of the world. They are just visitors
to the United States, with most sightings seen near the Dry Tortugas in
Florida, but with widespread sightings along both coasts, and a handful of
sightings on inland areas. They are easily differentiated from other
Booby species by the stark contrasting brown and white plumage, as they are
the only Booby species with a dark brown back, head, neck, and breast, with
a strongly contrasting white belly.
Habitat: Nesting colonies are on tropical islands.
Outside of the breeding season, some birds may disperse, and may be found
anywhere from close to shore, to very far out at sea.
Diet: Feeds mostly on fish, but will also take
squid and other marine life on occasion.
Behavior: Forages by plunge-diving into the water
in pursuit of prey. They will also sometimes swim on the ocean's
surface and grab food items while swimming.
Nesting: Brown Boobies build a mounded nest of
sticks, grasses, and various types of debris, placed directly on the ground,
or sometimes on a ledge on a cliff face. The female lays 1 or 2 eggs,
and both parents help to incubate them. Upon hatching, both parents
help feed the nestlings, with parents continuing to care for the young for 4
months or more.
Song: At breeding colonies, young and females make
groaning and honking sounds, while males have a higher-pitched whistling
sound. Brown Boobies are usually silent when not at breeding colonies.
Migration: Near breeding colonies, Brown Boobies
are often found year round, but with birds wandering further out to sea than
during the breeding season. Some birds may widely disperse after
Dark upper plumage and dark head with white belly is unique for adult booby
species. Most likely to be confused with
Blue-footed Booby at a distance.
Conservation Status: Populations have declined
somewhat in the last several decades, as introduced predators such as rats
wiping out some former nesting colonies. However, nesting colonies are
numerous and widespread throughout the tropical oceans, and overall
populations still remain strong.
The IUCN lists the
Brown Booby as a species of "Least Concern".