BROWN BOOBY 

 RED-TAILED TROPICBIRD 



WINDWARO 

 ISLETS 



Fig. 1. Caroline Atoll, Republic of Kiribati, with newly-named islets. 

 RED TAILED TROPICBIRD 1988 



22 - 

 20 - 

 18 - 



CAROLINE ATOLL 



Fig. 2. Distribution map of breeding red-tailed tropicbirds and brown 

 boobies on Caroline Atoll. September 1988. In this and the following 

 distribution maps, arrows indicate concentrations of breeding birds. 



a 



z 



0) 



< 



a. 



o 



z 



16 

 14 

 12 



10 



uveniles 



primaries 



scap 



downy 



eggs 



1.0 



0.5 



>- 

 < 



Q 



a. 



LU 

 0. 



CO 

 LU 



X 



u 



o 

 6 



160 



APRIL 



140 



MAY 



120 



20 



SEPT. 



Fig. 3. Approximate laying dates for red-tailed tropicbird nests found on Caroline Atoll in September 1988. In this and the following similar figures the numbers 

 of nests begun during a given time period (bars) were determined by tallying each nest into one of several age classes (bar labels): bar widths indicate 

 length in days for each class. The dotted line connects mean number of surviving clutches begun per day for each class. For example, a juvenile found 

 in September began its egg stage in the previous May or June. The number of days are counted backwards from field observations. 



157 



