J Payers 1974 Journal 25 April cont'd Arroyo Chico, Estancia Medland, 35 km S. of Tornacho (by road), Pto de Wadaniang, Pcia de Bs. As., Argentina in subunit 3, [illegible] is a almost, if not completely dry. This dry stretch continues from below 7 through to #12 of subunit 8, that is 415 meters. Above 8 (8-10) there is continuous water again. Grid totals: White-rump 39.4(43); Hudsonian godwit 9.5(9); Charadrius falllalandicus 11.5(16); Zonibyx modestus 2.4(6); B. Necked Stilt 8.4(12); Maguari Stork 3.2(5); B. hooded gull 0.3(2); Cinclodes 3.0(6) White-rump dispersion was again remarkable: almost half of the total birds occurring within 50m of subunit 9. Running down totals: White-rump 38.56(94); Hudsonian godwit 7.11(18); Greater Yellowlegs 9.1(1); Southern lapwing 2.0(2); Charadrius falllalandicus 15.39(52); Zonibyx modestus 5.15(20); Black-necked Stilt 0.2(2); Maguari Stork 1.0(1); Speckled teal 2.0(2); [illegible] Milvago chimango 1.1(2); Brown-hooded gull 1.4(5); Cinclodes fuscus 3.4(7); Coreendra piju 2.0(1). After completing these surveys I continued down the Arroyo searching for banded WR. Today I continued on part the southern border of Estancia Medland, going as far South as a place Huici called La Urqueta - the fork -, where a dam had been built and [illegible] then to a [illegible] (bridge over the Arroyo). Very rough map Estancia medland Estancia la Diana Estancia Atlantida Arroyo Chico Farmhouse road Tule stand the Tajamar small moint small moint La Urqueta BRIDGE The Arroyo changes character beyond Medland; in fact it begins to do so before leaving the Potrero in which Tower Clamos lie. We have always suspected that there is something unusual about this particular stretch of Arroyo because, though I did not realize it at the time, we put the grid on a section of Arroyo unusual for its high density of WR. Only later in the season did any of the stretch N of the linear grid devolve heavy WR usage, and today below the [illegible] Estancia Medland bridge, I saw only one within 200 m of the bridge. Estimate that I covered a minimum of 15 km of the Arroyo, and am confident that no WR evaded my detection. There were, however, many Zonibyx and Charadrius falllalandicus