JP Myers 1974 Colidris fuscicollis (13,21) Arroyo Chico, Estancia Medaland, 35 Km S. of Juninco by road, Ptdo de Madariaga, Pcia de Bs. Aires. 2 October Arag, Argentina 1050 - found flyby between subunits 7+8. it is possible territorial. went through instance of supplanting, but why conviction was consistency. (13,22) Arroyo Chico, Estancia Medaland, Ptdo de Madariaga, Pcia de Bs. Aires, Argentina. 1115 - definite territorial bird we have between subunits 8+9. very territorial bird - tail down, consistent supplantation, flying from 10's of meters. appears that when it lords after sup- planting it holds its wings up root - there is a distinct difference between the leading posture in a territorial bird as opposed to non-territorial. this individual is following intruders in clean flight for 30-40 m along the length of the territory, chasing less than 50 cm behind the chased bird, following every move. Sometimes chases when others fly over. it is foraging over ~70 m of arroyo, supplanting along both side. chase is intense. supplants from a min- imum of 40 m, probably 50-60. however sometimes inconsistent: orients into wind (as) so that birds can approach coming upwind (i.e. upa). but the territorial also forages downwind, + when it is it is consistent in position of supplantation. Grid 13 (13,24) Estancia Medaland, Ptdo de Madariaga, Pcia de Bs Aires, Argentina (finished linear grid run at 0755 - total of 25 wr on subunits. territorial bird in 10-3 perhaps 9.) 4 October 0800 began sampling Grid 13 - [illegible] then 10-4-74A began following 10-4-74A, a territorial bird on grid 13. took 1 hours following data. During that time it supplant an incredible 37 times, some of them flights of over 30m (as) was supplanted by neighbor as it intruded too far upstream. 10-4-74A shared borders w/3 other birds, 2 of which had controlled porchive of Grid 13. It appeared that 'waves' of intruders came in - then would be periods of contin- uous feeding (i.e. no supplantation) for up to 9 minutes, and then several minutes in which, in each minute, there was at least one supplantation. 10-4-74A ranged over (i.e. controlled) ~425 m² of area, only ~50m² outside of the grid. It was very consistent in its supplantation. During these waves, intruding birds would be chased from one building to another, sometimes not even being able to land. 10-4-74A fed 73% of the samples (i.e. 73% of times that it's position was noted, it was feeding.) One supplantation of a bird.