JPMayers 1974 Arenaria interpres Punta Raga, 15 km N of San Clemente by road, Pido de Gral. Lavalle, Proin de Bs.Air, Argentina 28 March 20-30 turnstones along a 400 m strocked mudflat, watching one eat fiddler crab. These crabs are quite small (5-6 cm long) and in a dense bank which they have prepared with their holes. The turnstone runs along, very frequently changing orientation + speed of movement. Stops, jumps a hill down a boll, + infrequently comes up with a crab. The crabs leave about a 0.5 m radius about the bird: as it approaches to that distance they retract into holes. 15 min later I found another turnstone clearing crabs. 1805 - so far I've seen no signs of space-specific aggression. I have seen an Arenaria chasing after another which has a bundle of food. Now here is one feeding on a dead (or dying immobile) crab in the mud, another is walking by, + coming into the crab. Unfortunately I am too far to see details of the interaction but the following process is evident: as the 'intruder' approaches, the feeding bird rotates about the crab so as to keep facing the intruder: inttrud motion -> From above motin <---crab feeder motion One of the turnstone here this afternoon has moulted considerably, not only on breast but also the head has a very muddy look to it. Others have not progressed so far, but all are obviously on their way out of basic.