Recuperaciones por condición para Ánsar campestre

Classical switch from mainly dead recoveries of shots before 1960 to mainly colour ring reads today, though dead recoveries still the second recovery condition, but less than 6% in frequency. Heterogeneities in temporal patterns of recoveries might ensue from changes in recovery conditions, but also more ring reads during the 1990s. European Taiga Bean Geese historically showed lower survival that Tundra forms, which might be due to heavier hunting pressure (Fox et al. 2021) which may affect our ability to recognise patterns in the two forms.

Movimientos anuales para Ánsar campestre

Breeders from Scandinavia winter in southern Scandinavia, mainly southern Sweden and Denmark, reaching northern Germany, few to the Netherlands. A few birds from Finnmark tracked with GPS wintered in southern Sweden, arriving there during the last decade of September, and leaving in the last decade of April. Most birds wintering in the Netherlands undergo a spring migration to Russia, reaching the Siberian tundra in the third decade of May. Migration to Finnmark mainly coastal, migration to Siberia mainly over the continent.

A recent tracking study provides novel information on movements of Finnish Taiga fabalis (Piironen et al. 2021); satellite-tracked non-breeders and unsuccessfull breeders migrate to the island of Novaya Zemlya in the high Arctic for wing moult, outside the breeding range, for approximately three months; migratory connectivity between breeding and moulting sites was very low; moult migrants began fall migration later in autumn than successful breeders, and their overall annual migration distance was more than twofold that of successful breeders; these tracked fabalis wintered in southern Sweden.

No separation of data from the two forms (tundra/taiga) here, so potential differences in timing between subspecies to be considered carefully (Heinicke 2010), as both forms seem also to locally hybridize (Ottenburghs et al. 2020).

Conectividad por mes por región para Ánsar campestre

No movements of wintering birds from end of November to the end of January, first movements towards southern Scandinavia noted early February, reaching Finland in March, installed in May (Nilsson 2011). Records restricted to northern Siberia after mid-May, so ongoing movements to the far-north during three months. In autumn, first notable movements noted in early September, to be completed during October. Far-eastern Siberian birds are on the move after the Scandinavian birds, and reach their breeding grounds later.