Contrôles par Condition for Mergule nain

Game species in Greenland and (under special regulation) in Russia.

Most encounters are obtained after 2005, exclusively during the breeding season – 99% in Jun-Aug (mainly adults): 19, 71 and 5% respectively. Encounters prior to 1960 are almost lacking. Those based on dead birds decreased markedly over the years – from 90% in 1961-90 (70% shot) to less than 1% after 1991. Inversely, the share of recoveries based on alive birds largely increased – from virtually none to more than 99% respectively, the latter mostly due to ringing encounters. The encounters based on shooting/hunting come exclusively from SW Greenland, while those based on alive birds – from Svalbard.

Ringing data from the Russian Arctic is absent.

Annual Movements for Mergule nain

Post-breeding dispersal starts in Aug or Sep. The species undergoes a flightless wing-moulting period after breeding season (Montevecchi, Stenhouse, 2020). Birds breeding in Svalbard and Bear Is during moult period move E into the Barents Sea, dispersing along the ice edge between S Spitsbergen and Novaya Zemlya (Fort et al. 2013). Later on, they take SW routes, subsequently being encountered in SW Greenland and Iceland mostly between Nov and Feb, Mar at latest.

Tagging of birds in E Greenland revealed an important post-breeding staging area (moult period) in the Greenland Sea (Mosbech et al. 2012), as well as wintering area off Newfoundland, ca. 2500km SW from the breeding colonies (Fort et al. 2012).

Breeding colonies are usually occupied in Apr-May (Stempniewicz 2001).

A theoretical model was recently developed of possible migration overturn driven by climate change, involving transarctic flights (Clairbaux et al. 2019).

Connectivité par mois par région pour Mergule nain

Dispersal movements are evident from late summer, prominent migration takes place in early to mid-autumn. The Svalbard population is encountered wintering in SW Greenland and Iceland from late autumn to early spring. Wintering concentrations are known from the sea waters around Europe as well – Norwegian and North Sea (significant) and Arctic ocean (less numerous) (Stempniewicz 2001). Barents Sea seems to hold wintering the population breeding on the Franz Josef Land archipelago (Montevecchi, Stenhouse, 2020).

Influxes and wrecks occurred on a number of occasions in W Europe possibly triggered by prolonged food shortages during or immediately following severe storms (Camphuysen, Leopold, 1996), like the North Atlantic winter cyclones (Clairbaux et al. 2021).