Journal Punta Raga, 15 Km N of San Clemente del Tuyú by road, Pto de Gral Lavalle, Provincia de Bs. Aires, Argentina birds foraging. There is a long, narrow strip of pelletly beach which appears to define the N side of the channel. On and around it were 65 godwits, 40 curlews, 27 knots, 30-40 turnstone. However, as yesterday, I am not overwhelmed by the great numbers of shorebirds. Why aren't there more? Others present include Charadrius falklandicus, (most numerous on this side of the channel where they predominate over LWR) 5-10 Tovar yellowlegs, many American oystercatchers as well as black-bellied plovers, only a few sandpipers. 0935 - total estimate of WCR is close to 1000, same for Charadrius falklandicus. 20 Ajai, a flock of mixed terns (80% Royal); 150 Kelpgulls, many brown-hooded. The knot total is over 100. Distribution of the birds now, at low tide, is not even even along the tidal front. Tanger present again While contemplating the tidal sharking line, comparing it with that in which I have been immersed for the last several months (i.e. non-tidal areas + mud flats in swamps) the major difference between their habitats [in terms of what factors affect the % of space-specific aggression] the probability that is one of temporal stability: A bird foraging in a suitable location in the non-tidal area with at time N will be able to forage at that location in N+1 is much higher than one foraging in a tidal area, except perhaps on a cyclical basis. The % of time the total foraging time avail- able to the bird which can profitably during which foraging near a tidal site location can be exploited is small with respect to the % at a non-tidal, non-cyclical location. These two variables are continuous - "% time available" and "probability at N+1" - how do they vary with respect to % of space-oriented aggression? Aecy. During the late morning until 1500 we were along the windward side of Punta Raga where we had been at the same time yesterday. The express purpose of the visit was to collect from the roosting site decided yesterday. However, we began our trek long before the tide had come up (it turned at about 1130), and thus spent a considerable time waiting for the birds to appear. When we first arrived, there was one Ch. falklandicus - it may occupy this area territorially. Other falklandicus were scattered along the beach, as were a few American oystercatchers, black-bellied