Spring migration of Red Knot Calidris canutus subspecies through N Europe

Based on available literature, we present an account of the spring migration through N Europe of Red Knots Calidris canutus of the subspecies canutus heading for breeding grounds in Siberia and islandica heading for N Greenland and NE Canada. Using counts in national bird databases, we describe the spring migration phenology of knots through Sweden and Finland during 1990–2016 and Estonia mainly during 2000–2016.

A few knots occurred in S Sweden in winter and in March and April. The main migration in N Sweden was during 10–17 May, which was earlier than in S Sweden (24 May–6 June). Few knots were recorded in migratory flight before 24 May in S Sweden (8%), Finland (4%) or Estonia (5%). The peak of migration in S Sweden, Finland and Estonia occurred during 25 May–2 June when 72% of migrating knots recorded passed through S Sweden, 77% through Finland and 51% through Estonia. In S Sweden and Finland, the main migration was over by 6 June; after that date, only 7% of knots passed through Sweden and 5% through Finland. In Estonia, 24% of migrating knots were recorded during 5–7 June and only 2% after 7 June. The cessation of the migration in June as recorded in our study was several days earlier than before 1990. We compare the timing of migration through Sweden, Finland and Estonia with that of knots migrating through the Kola Peninsula and the White Sea described in Russian literature (which is not easily available to non-Russian speakers). We also present other previously unpublished records for Kandalaksha Bay. The migration through the Kola Peninsula and Kandalaksha Bay in the northwest of the White Sea is earlier than in the southeast White Sea. In view of what is known about the spring staging sites of the islandica and canutus subspecies and data presented in this paper, we suggest that knots on the Kola Peninsula are probably islandica, those in Kandalaksha Bay are islandica or canutus or both, and those in the southeast White Sea are canutus.

Available in Russian: Весенняя миграция подвидов исландского песочника Calidris canutus в северной Европе, Дж.Р.Уилсон, П.С.Томкович, ISSN 0869-4362 Русский орнитологический журнал 2017, Том 26, Экспресс-выпуск 1500: 3919-3936