Rob Robinson

An exclusively marine, medium-sized seabird, occupying rocky coastal regions on steep mainland cliffs and offshore islands (Lavers et al. 2020). Its range extends across the temperate, boreal and low-arctic waters of the N Atlantic. Patchily distributed in Europe, from NW France and the British Isles to Iceland (holding the bulk of population), N Norway, Bear Is and NW Russia (Keller et al. 2020).

Season of assessment

B

Population trendIncreasing
Population size
(min-max, best estimate)		519000-1070000,763000
Red List categoryLC
Franks, S., Fiedler, W., Arizaga, J., Jiguet, F., Nikolov, B., van der Jeugd, Ambrosini, R, Aizpurua, O., Bairlein, F., Clark, J., Fattorini, N, Hammond, M., Higgins, D, Levering, H., Skellorn, W., Spina, F, Thorup, K. Walker, J., Woodward, I. and Baillie, S.R. (1) (2022) Online Atlas of the movements of European bird populations. https://migrationatlas.org EURING/CMS (1) Principal investigator
Mapa

Conectividad global para Alca común

Migratory movements are longest in high-latitude populations. Further S Razorbill is partially migratory, resident or locally dispersive. British Isles breeders are mostly found along the Atlantic coast of Europe from NW Africa to C Norway in winter, but also the W Mediterranean, reaching Tunisia and Italy and a few as far as W Greenland and the Azores. The Icelandic population migrates SE towards the Faroes and the British Isles; some reach S Scandinavia. The small population in NW France is resident. Baltic Sea region breeders move withing the region, often dependent on the sea ice coverage in winter. Birds breeding in NW Russia, N & C Norway are found locally and along the coasts of SW & S Norway and the Danish straits in winter (Hestem 2019), with some reaching the British Isles.

Recuperaciones por condición para Alca común

Razorbill is a game species in the Faroes and Iceland, but is protected in most of Europe. Most recoveries are in NW (69%) & N Europe (22%) with 68% in Jun-Jul. Recoveries of birds found dead decreased from 80% pre-1961 to 23% after 1991; those of live birds markedly increased from 5% before 1960 to 77% after 1991. The latter is mostly due to recaptures, including ring resightings. Shooting was an important factor in the past - 33% of all cases pre-1961, but now fewer than 1% of all recoveries are of shot birds. Currently 7% of all recoveries come from by-catch casualties (22% in 1961-1990). The species is vulnerable to oil pollution - now 2% of all cases (11% in 1961-1990).

Movimientos anuales para Alca común

After breeding, Razorbills undergo a flightless wing moult (Lavers et al. 2020). N Icelandic breeders moult locally (Aug-Sep) and some remain along the coasts of S Iceland in winter (Linnebjerg et al. 2018).; ohers move towards the Faroes (Oct-Jan). Birds breeding in the British Isles are found along the Atlantic coasts of N, W, and SW Europe, as well as NW Africa (mostly Morocco, but S to Western Sahara and even Mauritania; Isenmann et al. 2010) as early as Sep, most encounters are Nov-Feb. Summer encounters on the wintering grounds are of immature birds. Birds breeding in the Baltic Sea region overwinter locally, mostly in the S & SE part. N European breeders are found along SW & S Scandinavian coasts mainly in Oct-Feb. Breeding sites are reached from late Feb, mostly Mar-Apr (May at latest) (Cherenkov et al. 2016, Noskov et al. 2016).

Conectividad por mes por región para Alca común

Post-breeding dispersal starts in mid-summer. Birds breeding in the British Isles migrate and are found along the Atlantic coasts of Europe and NW Africa mostly between mid- to late autumn and late winter. First-winter birds from British colonies tend to migrate farther than adults (North 1980, Wernham et al. 2002). Some immatures stay in the winter quarters during their first summer; the proportion returning increases with age (Lavers et al. 2020). Birds breeding in W Europe and the Baltic Sea region are sedentary or locally dispersive. N European population (N Norway & NW Russia) take SW routes towards S Scandinavia and the Danish straits, where they are encountered primarily from mid-autumn to late winter; some continue as far as the British Isles (records are mostly in late winter to early spring) and France.

Referencias

Estadísticas Mapa
Nº de registros Nº de individuos Nº de recuperaciones
Datos en el mapa*
Total de datos disponibles
* Los datos del mapa incluyen solo recuperaciones lejanas (>= 50 km)
Referencias Mapa
2020 . European Breeding Bird Atlas 2: Distribution, Abundance and Change. European Bird Census Council & Lynx Edicions, BarcelonaEditor(s): Keller, V., S. Herrando, P. Voříšek, et al.
2002 . The Migration Atlas: movements of the birds of Britain and Ireland. T. & A.D. Poyser, LondonEditor(s): Wernham, C.V., Toms, M.P., Marchant, J.H., Clark, J.A., Siriwardena, G.M., Baillie, S.R.
Cherenkov, A. E., Kouzov, S. A., Semashko, V. Y., Tertitski, G. M., Semashko, E. V. 2016 . Present status of Razorbills Alca torda in Russia: occurrence, population and migrations. Marine Ornithology 44: 207–213
Hestem, M. 2019 . Should I Stay or Should I Go? Geolocators reveal different winter home ranges and -activity patterns in sympatrically breeding razorbills (Alca torda). Master’s Thesis. Norwegian University of Life Sciences
Isenmann, P., Benmergui, M., Browne, P., Ba, A. D., Diagana, C. H., Diawara, Y., and El Abidine ould Sidaty, Z. 2010 . Birds of Mauritania/Oiseaux de Mauritanie. Société d’Études Ornithologiques de France, Paris
Lavers, J., J. M. Hipfner, and G. Chapdelaine 2020 . Razorbill (Alca torda), version 1.0. In Birds of the World Link to Article (DOI: https://doi.org/10.2173/bow.razorb.01) Cornell Lab of Ornithology, Ithaca, NY, USA
Linnebjerg, J.F., Frederiksen, M., Kolbeinsson, Y., Snaethórsson, A. Ö., Thórisson, B., Thórarinsson, T. L. 2018 . Non-breeding areas of three sympatric auk species breeding in three Icelandic colonies. Polar Biology 41: 1951–1961
North, P. M. 1980 . An analysis of Razorbill movements away from the breeding colony. Bird Study 27: 11–20
Noskov, G. A., Rymkevich, T. A., Gaginskaya, A. R. 2016 . Migration of Birds on Northwest Russia. Non-Passerines. ANO LA “Professional”, Saint Petersburg

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