iiREurr 
DRIFT 2 
birds 
Table 
Resting Activity of*the Great Frigatebird on Enderbury Island 
February 
IV ' O -r 7- 
196 
,<cr 
77-1-1 
X310-21-0 
July 
665-735-995 
1204 - (948) 
825-651-264 
November 
46-0-387 
19 - (l/l5) 
\ 
In 
The First figure . .jrap re sente the number of nests containing eggs, 
the second the number ith snail goung md the thircz the number 
with large young • In July and November 1964 small j/nd large young 
were not distinguished in our counts,. 
t?o 
gg laying begins from 
January to March and by July most egg laying has 
ceased. Nesting activity appears to increase more rapidly in the Great 
Frigatebird than in tee other breeding species. In addition at any given time^. 
CX O \ 0$T } 
J^tT Great Frigatebird nests contain ggs similarly advanced in incubation or 
young of a proximalely equivalent ages than Ij/generally true In the other 
breeding species. 
/ 
as 
The cessation of egg laying seems /to be abrupt as its initiation. 
In November 1963 the young were over/two months old indicating a cessation of 
most egg laying in July. In November 1964 the young were sotely between one and 
two months old ^^2 laying ceased somewhat later than in 1963* 
1 
Fledging of young extends through December and immature birds spend several 
mont s in the vicinity of their former nests. Egg loss is very high in the 
colonies and renesting may be a partial explanatio n of the extended 
laying period. 
^trbuoiTcly ^ 
Reproduction: On Enderbury this species nests primarily in Tournefortia trees 
oves. 
or on the .ground 
■hile 
Red- ~ 
footed Boobnest| mainly in jjae Cordia gr< 
/a> ^r 4 a 
A tew- small number! {^1 25) nesWin a small circular grove of trees at the 
of ^ X ( 
Iff corner but :a- a': ■... . __sive 11 frigate cc a rf . ] OlCrth 
of the lighthouse and a y mile south of the F 
hill n * In July 19 63 the 
number of nests found in this latter area#* was about 1700 or approximately 
70% of the total nests present. A similar proportion (c v 62%) of the nests 
