Wood Sandpiper

The wood sandpiper is the smallest of the shanks, a group of mid-sized, long-legged waders that largely use freshwater and wetland habitats. It resembles a longer-legged, more delicate green sandpiper, with a shorter, finer bill, a brown back and longer yellowish legs. It differs from the green sandpiper in having a smaller, less contrasting white rump patch, whereas the solitary sandpiper has no rump patch at all. Its closest relative is the common redshank, which it shares with the marsh sandpiper. (Wikipedia, general species account)

The wood sandpiper breeds in subarctic wetlands from the Scottish Highlands in the west east across Eurasia and the Palearctic, and it migrates to Africa, South Asia, particularly India, and Australia. Vagrants have reached the Pacific as far as Hawaii. In the western Pacific and East Asia it is encountered between mid-October and mid-May, and it is a regular visitor to Palau and the Mariana Islands, where flocks of up to 32 birds have been reported. (Wikipedia, general species account)