J.P. Myers (1974) Journal Linear grid Arroyo Chico, Estancia Medaland, 35 Km S. of Tuenchelo by road, Pto de Madariaga, Provincia de Bs. Aires, Argentina 6 November (cont.) Vanellus chilensis 1,0(1); Steganopus tricolor 1,5(6); Himantopus h. 4,13(17); Chauna forquata 1,0(1); Anas flavirostris 2,0(2); Anas georgica 3,5(7); Larus maculipennis 3,5(12). In summary for the linear grid reading of this morning and this running up — the difference between today’s WR dispersion pattern and that of 4 November is considerable. Today they are evenly spaced almost along the whole length of the Arroyo. Everywhere was evidence of territoriality — much supplanting. There were a few groups of birds, although there were some. Ry Lya which had been territorial on 11–3 and between subunits 9 and 10 and then switched to sub 8–7 on 11–4, was back between sub 9–10 today. Ry Lya also switched back, although I had no indication of its territoriality. Ry Lya did the same. If anything, the dispersion of optimal habitat along the arroyo today is much more even than it was 4 Nov. The birds are also even, and they are territorial. (B)1 Estancia Medaland, 35 Km S. of Tuenchelo road, Pto de Madariaga, Provincia de Bs. Aires, Argentina 1800 began counting flying shorebirds from position used 9 October and 18 October. Weather during the day has been eventless — a moderate NE wind backtown continuously, cloud cover remained below 10%. Temperature risen to 25°C. Temperature at 1800 = 24°C. We counted until 1945 at which time light intensity fell (below 1 fc). total: Tryngites subruficollis 651 (+360 spooked); Calidris fasciollus 11; C. laicalis 2; Limosa haemastica 24; Tringa sp, 8; Vanellus chilensis, 62; Pluvialis dominica 29, 278 (+272 spooked); Himantopus h.j. temperature at 1745–1755. It began to look as if another thunderstorm was forming, advancing from the S. However, it never developed. Sunset at ~1927 (Obscured by cloud). There was some variability introduced into the count by the fact that 2 horse riders working taking sheep through a prime upland unit of habitat on the western side of the Arroyo, and later they passed along the road, going to the farmhouse. Large flocks flew in front of them. These were tallied separately in the flock account. If the spooked flocks are separated from the main body of 10 buffy flocks, and the latter latter plotted