Internationally important stopover area for the globally-threatened Common Pochard Aythya ferina in the Volga River delta

The Common Pochard Aythya ferina (hereafter Pochard), is a widespread freshwater diving duck of the Palearctic. A large and rapid decrease in abundance resulted in it being classified as Vulnerable in the International Union for Conservation of Nature’s (IUCN) Red List in 2015 and it is now considered to be a threatened species globally. The objective of this study was to provide reliable data on numbers and habitat use for Pochard in the delta area of the River Volga (southern European Russia) during their autumn migration. The total number of Pochard staging in the River Volga’s avandelta was estimated at c. 346,000–390,000 individuals in mid-November 2020 and c. 153,200–170,000 in mid-November 2021. Several sites with large numbers of staging Pochard were identified within the delta, and the Volga River delta currently holds the most important stopover concentrations of Pochard in the Palearctic. A large-scale monitoring and research programme is required for Pochard in the delta of the River Volga, because such information is essential for the effective conservation of this globally-threatened species