Red-tailed Tropicbird (13) 
Approximately the same number was recorded during the July survey. The 
increased numbers recorded in the grid during the July-August 1966 surveys are 
considered to be the result of buildup in the breeding population on Howland 
Island. One specimen was collected. 
White-tailed Tropicbird (2) 
Except for higher concentrations during October-November 1965* this species 
has consistently been recorded in low numbers or absent on all cruises to date. 
Blue-faced Booby (131 + 3 nocturnal) 
Density dropped from 0.388 in July to 0.2U5 during the present cruise. This 
reflects decreased grid activity near Howland Island rather than any decrease 
in bird numbers since numbers on Howland have remained much the same throughout 
the present breeding season* A blue painted adult was recorded approximately 
10 miles NE Howland on 18 August and a blue-streamered immature on the same day 
at 27 miles NE Howland. The majority of grid sightings occurred in close proximity 
to Howland Island during the period lii-17 August as consecutive grid legs were 
begun each day starting from that island. Up to a dozen immature birds invariably 
accompanied the ship out from Howland, some remaining with it as far as 20 miles 
out. Some individuals may have learned that flying fish are stirred up by the 
ship. 
Brown Booby (U i 1 nocturnal) 
Three of the four sightings were recorded on Hi August between Howland and Baker. 
The greater numbers recorded last month were correctly attributed to increased 
activity near the two islands. 
