JPM yeus 1977 Calidris pusilla Prokhor Bay, Alaska phenological notes on this species prior to 28 July are within the Journal. see 5 June, 26 June and 22 July especially. 28 July we must be near the peak of C. pusilla juvenile migration. see Journal for general observations. flocks strongly concentrated along littoral zone but also present in a few concentrations away inland—e.g. the WANA seepage pond, a disturbed site out by BP main camp (near Pad E) etc. Flock sizes up to 100 birds, but many small groups of 5–20 observed, foraging largely in littoral Puccinella marsh along base pond margins in red mud. groups also seen foraging on road in gravel taking dipteran. Important—we seen in area of salt water burned tundra—ponds lining by the margin, spilled out in old Carex marshes blackened by salt Carex and moss (Droguenocladus?) killed by salt water. a few newly colonized Puccinella phryganaides plants moving into area. ponds filled with diatoms copepods and fairy shrimp. very localized aggression: behavior— foraging on territorial note foraging by undisrupted individual limited to ~2 m of shoreline, certain aggression toward intruders, and several behaviors highly reminiscent of classic calidris kennerally: [illegible] sometimes tail cocked foraging or back raised thus birds will actually forage of back at wicked angle crouching on ground waving shake of tail cocked Thus there were good border displays involving motor solicitations crouching by 2 individuals. no good tail down however, even though I looked explicitly for it. The frenzy of the high density scene with 30 or 40 birds pushed into a distance of 30 m may have—almost certainly—precluded the full expression of a well developed array. 29 July more adventurous quickly as they came, they were gone. It's of pusilla juveniles were down markedly today, sufficiently so that qualitatively we felt certain in a drop in abundance