S.P. Meyers 1973 Calidris melanotos Grid J (Farmhouse puddle) Estancia Medland, 35 Km S of Juancholey road, Pcia de Bs. Aires, Argentina. 4 December (cont'd) 3 non-territorial pectorals in upper right hand area of grid (1,5)'s. (Are they the 3 that left earlier?) Why aren't they supplanted by the resident? [Aside - watching them forage; it occurs to me that their sites of probing - when they stick their bill - are along different from those typically used by WR. If I had to guess now what diminutive Pectoral WR separated here, one would be microtopographic features at the habitat: Pecks use mounds that stick out of the water indoor mats of grass just above the water line, whereas WR typically probe in water. In a place like this grid, where the walking action has created a myriad of molds + corresponding mounds, this means that the two species can forage side by side + get still use different sites. What role does the WR tongue musculature play?] 1420 If it is a territorial system - defending is not perfect. Those 3 birds had been on what was a defended area ~2 hrs ago for 20 min. The defending bird is about 20 m away. The following explanation is possible: the defending bird normally uses an area which is predominantly off the grid to the S, with some extension into the grid. However throughout the morning + early afternoon a S. lapwing was chasing everything away from the shrub in ~ from 10 m S of the grid to 50 m S of the grid. Thus the bird's territory was not all available to it, and it made an extension to the opposite side. When that S. lapwing has ceased to chase in that area, after returning, called me birds in an area no longer defended by the territorial bird. 1450: Pet landed 0.5 m SW from stake (4,2), just beyond "island" on which the (3,2) bird typically perches. The (3,2) bird (which was present) immediately arose, stretched its neck, and started walking rapidly toward the landed bird, picking at the surface. It seemingly fed like this until within 3' of the landed bird, at which pt. it ceased velocity movement. This neck outstretched, in an angle almost but not quite horizontal (but with it held out off the direction of motion): Note that the direction of motion is not directly toward the bird being supplanted the other bird flew as the supplantor reached reached within 1' or so of it and as the supplantor churned. But the individual flew only a short distance, and the supplantor followed.