R. Clapp 
1964 
Oct. 18 Jaboeruldcti-Aruraeni Islands, Rikar Atoll 
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In the afternoon walked north on Jaboerukku and 
thence over to the Sooty Tern colony to have a 
look at the Crested Tern 1 nests in their midst. 
Near the center of the Sooty colony is a small 
colony of Crested Tern. • Originally there were 20 
eggs and 2 chicks but the 2 latter died and 2 
rotten eggs were removed by Amerson. Today there 
are 14 nests encompassed in a very small area. The 
14 nests are in an area, which, if boxed in by 
a rectangle would encompasss 20 square feet. 
Subtracting about 2 square feet from the total 
would be justified as a certain amount of this 
area is not utilized by the birds. (The nesting 
area is more nearly oval.) This reives a nesting 
desnsitv of about 1 bird / 2 so. ft. or SO nests/ 
loo square feet. 
T then measured the distances between eggs and 
their nearest adjacent neighbor to the half inch. 
I got : 10,10,12,12 , 10. 5 t 11, 11, 11.5, 12, 11, 
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9.5, and- 9.5 inches 
The nest itself is nothing more ..than a sligjrt 
scooped depression in the coarse rubbly coral and 
sand. Such a depression is about 6 inches in 
diameter and about .5 to 1.5 inches deep. 
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One egg centrally located was 12,10, and 10 
inches from its nearest neighbors'. This “would make 
the mean radius of the territory about 5.5 inches. 
This would give the bird a territory ’of less than 
a square foot. 
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