JP Myers 1974 Tryngites subroficollis Tower Llanos, Estancia Medeland, 35 Km S. of Juaanco by road, Ptdo de Medariaga, Provincia Buenos Aires, Argentina 18 January cont'd in mb the llanos, chasing another blackbird: the latter (Q) moved a little, but the chasing bird continued the attack on foot, at which pt. both stopped + crowded, holding head low, back feathers raised. Both held ~15 sec before both continued feeding, Q going further away from ledge, + the ledge bird returning. As in this case, when ledge goes inland, it usually returns directly (feeding en route) to the ledge. 0865 Ledge bird stretched neck high + flew at another buffy ~ 5m beyond pt where L usually turns in its traverse near W end, + 3 m inland. The other bird did not yield readily, + both started hopping + wing flapping. 5 separate hopping bouts in a few minutes. Finally L [illegible] executed way down in grass, head low, without moving. Other bird could L 3-4 times, then walked hurriedly W, away from L + L's transect, + started to feed again. L then got up, ran toward other bird with head shift in aggressive attack. Both began hopping again, until L flew back to our territory, to spot from where L had initiated encounter. In these "aggressive runnings," the normal bobbing motion seen while foraging disappears - the head is held low and neck arched still somewhat outstretched (but not stretched). 0830 L still patrolling ledge. On our patrol a buffy on the opposite side of drainage (O), feeding along edge of drainage. L flew at him O, forcing O to fly. O went E along drainage. L followed, walking 20-25 m to within 5 m of O (which was then feeding, coming closer to edge of drainage). Then L walked into dirt area + across to "our side". An En route its pace became more rapid. When it got to base of ledge, it flailed both wings, and another flash + jump, causing a cob close by WR to fly (which may have been the object of the flash) + increased pace. As the WR flew L flashed again. Returned to Tower at 1700 after leaving at 1000 this morning. See journal for [illegible] description of curious dispersion pattern, 1819 first aggression in buffies on Grid 4. Watching 2 buffies in small (3?) quint. "A" came over directly from (5,2) without wing flash. Seems to be for- aging together. Began with, when A came up it half-jabbed, half-foraged