5.P.Mayers 1979 Trypanito subbruticollis 55 (1323) Estancia Medaland, Pto. de Madariaga, Provincia de Bs. Aires, Argentina 13 November 0815 just collected 2 non-ten. bufffios from [illegible] short-grass. I had watched them for 35min for sign of space-specific aggression, but saw no aggression whatever, even though they were foraging together in circumstances which, had they been territorial, would have generated aggression. (1725) Estancia Medaland, Pto. de Madariaga, Provincia de Bs. Aires, Argentina 16 November Photographing bufffios this a.m. from blind, placed in dense treffly area pre- dawn. They looked to me fairly readily, and during the early morning there were frequently bufffios nearby. Some supplementating and at least 5 good territories nearby. However, the consistency of supplementers declined markedly after one prolonged spook ~0830. Finally by 1045 they were beginning again, although 'tentatively' and only heliopetra flight + subdued side-head supplementing. Foraging very space-limited. Collected a territorial bird, of the above sort (176) Tower Llanos, Estancia Medaland, Pto. de Madariaga, Provincia de Bs. Aires, Argentina 17 November Taking microhabitat data on bufffios, 1630. - appears to be a series of ten birds in this area (1215). Although now we have disturbed them, they continued supplementing even after I took the first few points. One wing flash with us at close range, directed at a bird which had just left because of us. Possible that this is an edge effect: the birds are foraging near the edge of the canopy where there is a steep (vertical) street, broken defining thread of bufffio habitat. Several if not all of the ten were near that. 1720: we have been bothering them for some time, now. Must be going about in a directional flock. 1820-From (8.11) observation post. Territorial birds took us if they abandoned, particularly on the S side of the clearing. Still, ditch once there is not only an edge, but where the dendritic form of the canopy creates + defines a series of patches. At least 2 of these are used by one ten bird/patch. See flocking accent in totals. In the mid-afternoon period to ~1730 botha were foraging as a phalanx - running a few steps, cocking the neck as they ran + leaning over, then