9 
Blue -faced Booby . . . Demon or Dunce ? 
The Blue-faced Booby is one of 
those species whose dispersal and 
at sea distribution has been most 
intensively studied by the Smith- 
sonian Pacific Program. Many of 
these birds, also known as the 
Masked or White Booby, have been 
seen hundreds of miles from the 
nearest land. A few young birds 
have even been collected over a 
thousand miles from their natal 
island. 
While at sea, the Blue-faced 
Booby courses the sea lanes search- 
ing for its favorite foods, flying 
fish and squid. These birds 
occasionally alight on the ocean 
but prefer to roost on floating 
objects such as driftwood logs, 
old crates discarded by passing 
ships, or sometimes even sea 
turtles . 
Blue-faced Boobies nest abun- 
dantly on scantly vegetated Central 
Pacific islands. In the nest, 
which is only a circular scrape sur- 
rounded by a thin white line of 
excrement, two eggs are laid. Only 
one young is raised, because the 
first hatched, larger nestling 
pushes its younger sibling out of 
the nest. 
On their breeding grounds, 
these birds, the largest of the 
boobies, are perhaps the most 
dangerous species encountered by 
POBSP banders. They are particular- 
ly aggressive when defending their 
nest sites from human intrusions. 
At such times the raucous honks of 
the female, piercing whistles of 
the male, and vicious lunges with 
bayonet-beaks by both sexes, will 
dismay even an experienced bander. 
Such antics led one observer to 
call them "shrieking demons", and 
others, less lucky, have often des- 
cribed them in a rather more vitri- 
olic manner. 
Despite their ferocious de- 
fense of "home" the Blue -faced 
Boobies do not recognize their eggs 
or young chicks, and will uncon- 
cernedly trample them underfoot 
when disturbed. With complete 
equanimity nesting birds accept and 
incubate such objects as worn sea- 
shells, stones, and spherical glass 
fish net floats. One Blue-faced 
Booby was even seen incubating a 
live hermit crab but, admittedly, 
the bird appeared somewhat puzzled 
as its "egg" crawled away from the 
nest . 
Many such incidents suggest 
how the species received its dis- 
paraging popular name (derived 
from a Spanish word for "dunce"): 
however such behavior has not pre- 
vented this species from being one 
of the most abundant of the larger 
tropical seabirds, with over fif- 
teen thousand breeding pairs in 
the Central Pacific alone . 
- Roger B. Clapp 
Blue-faced Booby and chick. Photo by 
W. 0. Wirtz, POBSP. 
