Updated breeding range of the Terek Sandpiper Xenus cinereus with additional data on nest densities

This paper updates the known breeding range of the Terek Sandpiper Xenus cinereus in Russia, Belarus and Ukraine, based mainly on published sources. Most Terek Sandpiper breeding sites identified in this study are within the breeding range described by Gladkov (1951) and Cramp & Simmons (1983). Only a few new nesting sites were recorded well outside this range, but more were encountered slightly to the north between the valleys of the lower Ob River and the lower Pechora River, as well as on the banks of large Lena, Yana and Indigirka rivers in Siberia. The fact that nests have been found in the Smolensk and Bryansk regions of W Russia adjacent to Belarus indicates that Belarus and Ukraine are not inhabited by a discrete breeding population, as has been suggested. No breeding Terek Sandpipers have been found throughout the vast territory of the upper Yenisei, Angara and upper Lena rivers the Amur River area and the upper Kolyma River, or in SW Siberia, including the Tobol River valley, the upper Irtysh River, and the Altay steppes. In the north and north-eastern parts of the breeding range, Terek Sandpipers concentrate in river valleys in densities that are much higher than in the western parts.