BREEDING BIOLOGY OF THE DESERT WHEATEAR (OENANTHE DESERTI, MUSCICAPIDAE, AVES) IN AN EDGE POPULATION IN NORTHWESTERN KAZAKHSTAN
Over the last two decades, the range of the Desert Wheatear has expanded and the species started breeding in northwestern Kazakhstan. There are, however, almost no studies on the breeding biology of this northwesternmost edge population. In this paper, we provided data on the breeding biology and space use of the Desert Wheatear near the village Isatai, Atyrau Region, Kazakhstan. In 2012–2016, no less than 17 breeding pairs bred as a dense settlement next to Isatai within a 650 × 470 m plot. The local density was thus 0.55 pairs per ha, and the distance between the neighboring pairs usually was less than 100 m. Such dense settlements seem to be unusual for the Desert Wheatear in Kazakhstan. We assume that the local features of small cattle grazing may have caused the formation of this dense settlement. At the same time, habitat and nest site selections, as well as the breeding phenology of the Desert Wheatear in the vicinity of Isatai are generally the same as in southern Kazakhstan (i.e., central populations).