* 
BULWER'S PETREL (Bulweria bulwerii): At-Sea Distribution and Abundance 
The following maps represent all At-Sea observations made by 
personnel of the Pacific Ocean Biological Survey Program from February, 
1963 > through August, 1965 * 
Each square represents one days observation from the first through 
the fifteenth of the month, while each circle represents one days 
observation from the sixteenth through the thirty-first of each month. 
Numbers refer to the actual number of birds observed during the day. 
Color code: 
yellow = 0 birds 
green = 1-10 birds 
blue = 11-50 birds 
red = 51-100 birds 
brown = 100+ birds 
