4 
The Variable Red-Footed Booby 
The Red- footed Booby, found 
throughout the tropical oceans 
of the world, is one of the most 
familiar seabirds of the central 
and western Pacific. Its plumage 
coloration varies widely from area 
to area. So different are some of 
the plumage morphs that on occasion 
one form or another has been de- 
scribed as a distinct species. In 
the Leeward Hawaiian Islands, for 
example, most birds are white with 
black wing tips and a faint golden 
wash on the forehead while in other 
areas breeding birds are all brown 
with white tails . In the Phoenix 
Islands a third plumage morph pre- 
dominates in which the back and 
wings are greyish brown while the 
tail, neck and head are white. This 
third morph is highly variable; 
some birds have white half way up 
the back; others are greyish brown 
to the base of the tail. Some 
breeding birds have faint brown 
breastbands much like those of im- 
matures while others entirely lack 
the band. Occasionally the white 
Red-footed Booby nest on abandoned 
oil drum. (Photo by R. B. Clapp) 
morph, similar, but smaller than 
that found in the Leewards, is 
present and still less frequently 
the brown white- tailed morph is 
seen. 
The male and female are 
similar in appearance throughout 
much of the year but as the 
breeding season approaches changes 
in the soft part coloration make 
the two sexes readily distinguish- 
able. In the male, the patch of 
exposed skin at the base of the 
bill changes from pink to a 
distinct orange and the blue of the 
bill takes on a pronounced greenish 
or yellowish-green cast. In the 
female the base of the bill becomes 
bright pink and the blue shade of 
the bill becomes more intense. 
Like their larger relatives, the 
Blue-faced Boobies, Red-foots are 
often chased by frigatebirds intent 
on depriving them of their dinners. 
The Red-foots do not take kindly to 
such treatment and dive, twist, and 
turn in their attempts to escape, 
raucously screeching all the while. 
Under other circumstances the 
tables are occasionally turned. On 
Green Island, Kure Atoll, POBSP 
members once observed two birds, 
one a young Red- footed Booby, the 
other an immature Great Frigatebird 
engaged in what was apparently play. 
The frigatebird had seized a long 
strand of beach vine and was 
sailing along with the vine dang- 
ling below and behind. The young 
booby, in hot pursuit, continually 
tried to seize the trailing vine 
with its beak. The frigate kept 
ducking and twisting in an effort 
to avoid the booby's harassment but 
the chase continued for at least 
fifteen minutes before the two 
contestants wearied of their game. 
(cont’d on page 6) 
