JPMyers 1979 Journal Tower Llanos, Estancia Mekland, 35 Km S. of Juancho by road, Pto de Madurinza, Provin d Buenos Aires Argentina 23 January (contd) the grid readings. Combined with a series of following data for buffeo by both Lois + myself during the morning we have a very good picture of the way in which the buffeio divide up Grid 10 (see ap. accent). Southern lapwing aggessions during the morning in (3,1), (0,2), (1,1), (1,2) of 4b created a state of flux in the shorebird division that was difficult to handle because of the instability. It is particularly evident in the 730, 900 and 1000 readings. The birds are chased out of these again, they go into the eastern areas of (0,1) and all of (2,1) and (3,0) and then begin working back. This creates a cyclical pattern in this division, because once they work their way back far enough the lapwings chase again. During the afternoon Buffie density on Grid 10 decreased dramatically. Grid totals - 36 samples. Buffie 2.5 (0-5) 93 White-rump spiper 0.2 (0-1) 8 ; Golden Plover 0.2 (0-1) 7; H.galwit 0.1 (0-1) 5; WR Swallow - (0-1) 1 ; Geositta curicularia 0.8 (0-2) 30; Correndera pipit - (0-1) 2; Zonotrichia - (0-1) 2. Buffie density before noon (13 samples) was 3.8/sample. Afternoon (23 samples) = 2.2/sample. Grid 4a (14 samples) Buff-breasted Spiper 4.9 (2-7) 68; Golden Plover 2.1 (0-5) 32 ; H.galwit 1.6 (0-6) 22 ; S.lapwing 0.4 (0-3) 5; Pseudoleistes viacecens - (0-1) 1; Anthus concolor - (0-1) 2; Rufous backed negrito 0.3 (0-3) 4; WR Swallow 0.4 (0-5) 6. Grid 4b (contains 4a) ; Buff breasted Sandpiper 9.6 (5-12) 135; Golden Plover 3.1 (0-6) 44; Hudsonian Godwit 2.6 (1-6) 36 S.lapwing 1.9 (0-6) 26 ; Pseudoleistes viacecens 0.3 (0-3) 4; C pipit - (0-3) 2; R.b.negrito 0.5 (0-4) 7; WR swallow 0.4 (0-5) 6; Cow 1. (0-8) 15. Hmm! 24 January We arose early before dawn and were at the tower before the sun but the horizon (0650 ADST) Temp at 0600 = 13.5° N. wind, 20% cloud cover (coming from NE). Effort this morning directed at obtaining additional buffie following data with which to compare contrast within yesterday's data. This turned out to be more difficult than anticipated (the equally interesting) because of the more transient character of most of the buffeio we followed. One seemed to be the same bird as yesterday, several others could