While scanning the big pit for shorebirds two birds seemed out of place among the Least Sandpipers. These two were drinking from an open pool. Larger than a Least SP. Finch/Sparrow head look to it, Yellowish throat, very White belly, pinkish legs. Defined supercillium. Eyering, no marked wingbars. First thoughts are JUV of any of these three: Horned Lark, Dickcissel, Bobolink. Both birds kept thier backs to me most of the time.