1963 Green Is; Kure Atoll, Hawari, Pacific Ocean R. Clapp - Journal - Dec. 15 Much of the morning was taken up with records and upon the activity study. Prior to beginning the activity study a single fairy tern was seen flying over the island in the vicinity of the boat pier. Spent some time during activity study watching displaying haysan at foot of tower. While earlier displaying vigorously at the time of observation they were merely facing one another, frequently dropping bill to ground to manipulate or near manipulate small objects at the surface. There were occasional instances of tucking the bill under the wing but none resulted in the full, rather formal display, with a bill snap upward. This preening under the wing, while perhaps serving a display function is not ritualized as in the bill snap upward; and the release of the head from under the wing has a very "casual" appearance. Occasional preening of the breast feathers took place by both birds. Shaking + ruffling the feathers also occurred. Besides bowing and mandibulating at ground the birds grab gently at one another's bill and nibble one another around the neck. The aforementioned behavior patterns occur either when the birds are standing up or when both are resting on their tarsi in the sand. One of the two birds neither of which had yet been handled by us; roached down, picked up a small straw; turned its head and put it behind it. Possibly this is some antecedent of nest-building behaviour partially