12. the immature birds in the flocks. The frigates in the southern areas could be from the Marquesas (or Tuamotus) which was the nearest land. Perhaps the birds north of the equator were from the Line Islands and consequently had no frigates associated with them. The islands off the American coast that have Sooty Terns are another possible source of these birds, but they have a spring breeding cycle which would not account for the immatures in the flocks, especially since the direction of flight would indicate that they would be returning to the islands to nest. All of this is of course, pure conjecture and must await further work in the area before any definite statements can be made. Fairy Tern (Gygis alba) Fairy Terns were found in fair numbers south of the equator and only occasionally north of it (see figure 19). The data from this grip indicate that this species wanders great distances from land, as one was seen well over 1,000 miles from the nearest land, and they were common at the 600 mile mark. Cetaceans Figure 4 shows the numbers of mammals seen per day during the trip. They were most common near the equator and in the California Current, but were almost totally absent in the Southern Hemisphere.