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Galapagos boobies
 The
three species of boobies in the Galapagos are certainly the commonest and
most frequently seen of the
seabirds.
Looking similar to gannets, and in the same family (Sulidae), they are large
birds, 70 to 90 cm in length, with long (1-1.5 m) narrow wings. Their long
pointed beaks give rise to their local name "piquero" (lancer), but no one
seems certain where their English name "booby" came from. "Bobo" is a
Spanish word for clown and may be the root of the word.It is thought that their name originated in the
seafarer's term for them,for they appear stupid, often showing no concern on
being approached and captured. Boobies frequently perch on ships at sea,
some-times using a vantage point near the bow from which to dive on flying
fish skipping away from the bow wave. The word "booby-hatch" is almost
certainly derived from their habit of perching at the bow.
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 The
boobies all have a strong, direct flight with several powerful rapid wing
beats followed by a glide. When in groups, they often fly ill a ragged line.
All species of boobies feed by spectacular plunge diving. When hunting, they
will fly with their bill pointing fifteen metres or more above the water. On
sighting their prey, they check their flight and hurtle in a headlong dive
to the sea. After seeing them hit the water at break-neck speed and bob
backup to the surface, one wonders how they survive the shock. Boobies and
gannets are well built for penetrating air and water, with a pointed,
tapered bill, torpedo-shaped body, and pointed tail.
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Air sacs in the skull cushion the impact of the dive and closed
nostrils prevent water from being forced in.
 All
three species are colonial but, in the
Galapagos, they
range from the widely distributed small colonies of the blue-foot to larger
and less frequent colonies of the masked to a few huge colonies of the red-foot.
An unusual feature of the breeding biology of boobies is the way in which
they brood their eggs. The developing embryo needs a constant temperature,
and in most bird species this is provided via the bare skin of brood patches.
These are areas with few feathers and a good supply of blood vessels so as
both to monitor the temperature of, and to provide heat to, the eggs.
Boobies and gannets, together with cormorants, pelicans, and tropicbirds,
incubate their eggs on their foot-webs which are well supplied with blood
vessels.
By either nestling down onto the eggs or raising the body
so that cool air may circulate, boobies can maintain the temperature
precisely around 39°C. Readers wishing to pursue studies of the boobies
should consult Bryan Nelson's The Sulidae (1978).
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