Great Frigatebird (Frigata minor): 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 actual number kf birds counted for each day. Blue line encloses total area of occurrence. Red indicates exceptionally high numbers.