J.P. Myers 1979 Calidris fuscicollis Arroyo Chico, Estancia Merckland, 35 Km S of Tandil by road, Pte de Malanang, Piccia de Bs. Aires, Argentina 22 April cont'd woo Ryleo. Again today I was impressed by the tightness of (C.R.) grouping during the early morning foraging hours. 1023 began taking following data on Ryleo. Between subunits 5 and 4 when I had lost Ryleo after. The S wind appears to affect the foraging direction of Ryleo — only very infrequently (less than 5 min out of the plot) did it force facing downwind. Any downwind movement was usually accomplished by flying. The wind therefore probably has an effect upon the location of Ryleo’s foraging position because it will result in Ryleo spending more time in the southern part of its territory or perhaps even beyond if there is another food. Wind to S: Keep it back. Almost all of the feeding up to minute 32 has been deep-pelving with bill, standing in water up to its belly + repeatedly plunging the head under the water. Head under no longer than 2 sec at a time. So far there has been no intra-spec. interactions — there aren’t any more won near it. At min 14 two adults had worked down from the IV to the 12-13 region of sub 5, where last month Ryleo would have supplanted them from. It is over 60 m from them, however. At minute 15 they left, flying N. Also (minute 30) a we flew upstream (downwind) from the S and supplanted Ryleo, which flew further downwind. Chased by Zorilbyx at minute 42. A few minutes near the end of the observation period were the only period when I saw Ryleo foraging in the classic search-peck style of the Arroyo — a mode which used to be Ryleo’s only foraging mode. During the 60 min following period I saw only those above mentioned aggressive interactions involving Ryleo. During NONE of this period did it forage on any of its old territory, though this morning and at other recent times I have seen it there. Although the foraging behaviour — particularly the space specificity, and its solitariness — strongly suggest that it may still be territorial, there were no intrusions into its present area — which would have allowed me to say whether or not it was defending that area. Ryleo preened for only 2 minutes of the entire observation period, immediately after it was chased by Zorilbyx. 24 April 1900 — Ryleo in a flock! between subunits 2 and 3. Took Microhalutat data on Roboy 25 April 0827 — Subunit 3 two feeding within 3” of one another in the same hole