A group of five pectoral sandpipers frequented the shore of Barrier Lake (July 29, 1951) but the group was not seen the following day. On August 3, there was a sudden increase of pectoral sandpipers in the area; most of them were in flocks of six to 50. From one point along edge of the uplands, we shot 20 birds from several different flocks consisting mostly of juveniles. They seemed curious about our presence. When a bird was shot from the flock, the entire group circled back and forth over the dead or injured bird, sometimes only three or four feet above our heads. In the late evening of this same day, the number of pectoral sandpipers increased and although some were moving westward, most of them were moving eastward. On the following day they were still present in great numbers. The day before the arrival of these migrating birds, two adults (Aug. 2) acted as if they were still attending young. On July 30, we shot at a lone bird as it flew by and thereupon it climbed upward until nearly out of sight as they frequently did when chased by falcons. At Lake Schrader (July 23, 1952) pectoral sandpipers were active 24 hours of the day. On August 4, 1952, at the south end of Lake Peters, a group of eight pectoral sandpipers fed near camp. On August 5, one was shot and on the following day only seven were seen, suggesting that they were established in the area and were not migrants. They left on August 12. At James Robert Lake (3600 feet elev., August 8, 1952), which is the most southern body of water in the canyon south of Lake Peters, several pectoral sandpipers were feeding along the edge of the lake and on the alluvium outwash below James Robert Glacier. At Gavia Lake there was a decided trend in movement of groups of pectoral sandpipers. On August 22, 1952, groups of 2, 4, 6, 8, 8, 8, 16, 17, 18 flew by to the east. The day before there were only a few sandpipers and these were not especially on the move. Comparison between dates of active movements of sandpipers in 1951 and 1952 indicate that migration was considerably earlier in 1951 than in 1952. +Erolia bairdii+ (Coues): Baird's sandpiper.--Specimens, 5: Topagaruk, 155 deg.48', 70 deg.34', 10 ft., 4, Nos. 30657-30660 including 2 ad. males and 2 ad. females, July 7, 9, 10, 1951; Kaolak River, 159 deg.47'40", 70 deg.11'15", 30 ft., 1, No. 30656, ad. male, July 12, 1951.