SPmyers 1973 1974 Tryngite subaucticallis Tower Llanos, Estancia Weedland, 35 Km S of Junincho by road, Pcia de B.A. Argentina 19 December cont'd I was taking survey of grids in the Arroyo. Upon returning my attention to the llanos, I find a (probably the) buffy in the area where I had noted territorial behaviour. It had disappeared when several cows wandered into immediate vicinity 7 minutes ago. 0645 - just took count grid 4, noticed buffy acting up in field grid, in (32) unit of 25x25 area in grid 4. First thing I saw was a buffy running across field with his right wing raised vertically. E. Then another bird followed it, flying from the area from which the first had run, to the place where the first had run to, the running bird stopped when the second buffy landed and turned, & then jumped up and down, with wing movement, ~ 6 times. The jumps carried it at least 5 inches (between ft + ground) off ground, purely vertical. This bird then flew away, continuing in the direction in which it had been running. The jump carried some. 15 January 1840 drive onto llanos w/ Lois. Parked car ~200 m W of gate from fallow corn field. Sat watching 105 19 buffies with 1/2 girls (6 E) with 200m radius of car. Many of the birds are sitting in clumps of grass, on top of old ant hill or behind them or near Coupa, preening or resting. Others feeding (~30%) In same radius see 27 golden plovers, similarly engaged. Feeding rate data of buffy (tape 2 side 2) One of the birds I took data on flew into the vicinity of bird that Lois was watching. Another buffy flying at the same time, the birds intrusion produced effect on the preening birds: the first bird to fly in flew in straight walking towards the preening pair (B+C). B turned his body sideways (perpendicular to A), though did not mix from position even though A was within a foot of B. When A began to turn away, B lifted its wings, and jumped up/down, at which point C got up, lifted its wings + jumped up/down. B+C started walking hurriedly after A, which was walking South. Then the buffy (B) opened both of its wings facing A & held them open but cupped - like a parabolic reflector with A as the focus. (From above) B For the displaying bird stood upright with neck outstretched. However it did, the four of them (B+C, A plus other newcomer, D) are feeding within a 10m radius - all headed S (our preening). We have not traced which is which except for the fact that the one that has moved least away from the original spot is B the display. A made no obvious display in response to A. All four birds, plus nearby Golden, circled simultaneously. We saw nothing to break that. Within 45sec they were moving + feeding again. 1910 - birds widely separated now x 10 S -> [illegible]