Boobies are the comics in the cast of Galapagos
seabirds. One of the strangest things about them is the name. Most people agree booby comes from
the Spanish bobo meaning "clown" for its blue feet and peculiar antics during courtship. But
the Spanish name today is piquero meaning "lance" for the sharp pointed bills.
Boobies occur in warm temperate oceans throughout the tropics. None of the booby species is endemic to the Galapagos, but
they have exceptionally high populations — the world's biggest in the case of the red-footed booby.
It's easy to see why early sailors must have been amused by their antics. Their courtship displays are elaborate
performances of calling, dancing and presenting. The reasons for the complicated courtship has not yet been worked out in
detail, but it may be related to preventing species cross-breeding. Also boobies are astonishingly oblivious to human
presence. You need to be within a couple of yards before they notice your presence. Even then, they carry out their lives
as though you were not there.
Of the four species of boobies, three are native to the Galapagos. These seabirds are classified in the family Sulidae,
related to gannets of northern temperate oceans, and share their typical feeding method — plunge-diving. On land
they may be comical, but to see a flock of boobies diving en masse is one of life's great spectacles. They hover a while,
waiting for the glint of a fish below the surface. Then with incredible power yet finesse, they drop from 50 feet or
more, folding their wings close to the body and pierce the water. They often chase the fish underwater before catching
it. To absorb the impact the booby skull has air sacs to lessen the shock — and they have many marvelous physical
and behavioral characteristics superbly adapted to their lifestyle.
Boobies have an area of distensible (stretchy) skin at their throats below the bill. When the bird is hot it holds its
bill open and flutters the skin of this so-called "gular pouch" and water on the inside evaporates, cooling it
down. This is not a very effective cooling system and when the weather is especially hot, boobies are prone to
overheating and death as a result. This problem is a particular hazard during breeding season, when the birds have to
stay on the nest, without a break, or food — often for days. Lacking natural predators, the only other major
threat is starvation, especially during El Niño events, when their favored prey — small sardine-like fish
called salema — migrate away to avoid the warm waters. However, since humans introduced cats, dogs, rats and
pigs, "unnatural" predators have become a significant danger. On islands where feral animals are common, boobies
are not doing so well. However, on most islands, which are too small to have interested sailors and settlers, the boobies
thrive to this day.
All the Sulidae breed in large colonies, so there is often stiff competition for nesting space. To avoid competing, each
species differs in their courtship rituals, nesting habits and where they feed — read more about these
differences and see the booby photos on the pages below.
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