10-4-63 ( cont. ) 
a sizeable number on immature boobys of Masked and 
Red-footed species which are in intermediate plumage 
stages from 2 Birds-of-the-Year to Adults. I hope to 
obtain a series from this island where Chan Robbins has 
done so much tagging of these species in the past. I 
estimate now that there are 75 pairs of Broun Boobys here, 
120 pairs of Masked Booby, and 800-1200 pairs of Red-footed 
Boobys nesting here. I would also judge between 600 and 900 
pairs of Great Frigatabirds here. 
10-7-63 
This has been a good day. We began early when Bill 
got up before seven to work his study area for the first 
time. I set out to mark several Brown and Masked Booby 
Nests and to tag any other adults which we might have 
missed. I set up seven study nests, two Masked Booby and 
five 3rown Booby. One Masked nest has a new e^g, and two 
of the Brown nests have new eggs. Tagged severl more 
Juvenal Masked, and a couple of Browns. Then Bill spotted 
a largem Shearwater-like bird which I collected. I believe 
that this is a Giant Petrel: All blackish-grey, short 
necked, very robust; Adult Female, ovary 1*3 x .7 Cm. with 
largest ovum of 2 mm. ( suggesting a S. hemisphere bird 
with reversed breeding cycles to N. hemisphere birds ). 
The bird was very fat, weighing 405 grams. Skinned it and 
saved a partial skeleton. In the afternoon went hunting 
for a few minutes and promptly bagged a Sharp-tailed 
Sandpiper ( Erolia ), and saw what I believe to be a 
Black Turnstone, and a Dunlin. The Dunlin was at quite a 
distance and I make this guess at the birdss identity 
with reservation. Then went to help Bill with the resetting 
of his traps and rousted out a Skylark ( A iauda ) which 
was then collected. This bird is the " sparrow 11 which we 
have seen for the past two days, and is probably the 
same species that I shot at and lost about a week ago. 
The two birds flew the same, acted the same, and possessed 
white outer tail feathers. And, before the first bird was 
killed I had seen two birds flying together: After shooting 
the first bird and losing it I saw only one. Skinned the 
sandpiper in the evening. 
r ~ 
