fC C\ v' 1 Hi i/y* i 
J n>r 
m k? t f j 
p &jy V I 
1 ■ J Iff 6 Lf 
BIRDS 
?• *\ c. 
3 V 4 ^ 
//’; 
^ / m r & * r 
Smqerbury DRAFT 2 
. > 
BLUE-FACED BOOBY ( Sula diactylatra ) ~~ __ 
f m 
Current Status: Com on resident and k-uyfe most abundant breeding species 
/7h> 
J 
Prior Records: Cassin (1858) who~pepep4ed—©n~4he reported that the Blue-faced 
Booby was jae^ert abundant on Honden and Enderbury Islands and that they were 
’'sitting and hatching" in January 1841. Munro (M3 1938) notdd that the species 
waw "common 11 in July, 1938 and in the Spring of the following year James 
E.A« Kinney banded 150 adults between April 2nd and May /5th* 
Population: The Blue-faced Booby populations cn Enderbury fluctuate considerably 
throughout the year. fflr 1 1 gg-*--popii • tinr rnnnar^-.^ 
and. the 1'frgest was luOO birds in November 1964 
, 
^ ' r jj 
and an almost equal number were present on tIsland' in July J The largest 
populations are present well after the breeding peak but the smallest populations 
are associated with little or no nesting activity* 
inland 
A considerable proportion of the population consists of 
non-breeding birds as is shown in tfeble 
below 
Table 
uly 1963 
ovember 1963 
ebruary 1964 
’uly 1964 
'ovember 19 64 
'ebruary 1965 
Lay 1965 
composition of the 
Variation in^Blue-faced Booby Populations on Enderbury 
Oj_ 
Number 
Nesting Bird 
o 
■790 
200 
ifimEl a**. UMH. 
850 
620 
40 
150 
Number of Non- 
Nesting Birds 
1100 
1500 
400 
75C 
1400 
750 
550 
Percent of 
Population nestin 
63 
The number of nesting birds is baaed on an actual count of the nest- with 
less than 1% error* The number of non-nesting birds is an estimate made 
from the number of birds banded but is probably accurate to within 10^. 
The breeding population in both 1963 and 1964 was at least 1,000 and 
ably closer to 1,250 (see Appendix A). Over 2,?00 adult .....nd 35C subadult 
island from July 1963 through May 1965* A 
Lincoln index calculation based on May 1965 recaptures indicates that the 
