The Barnacle Goose (Branta leucopsis) is a frequent winter guest and migrant on the northwest European North Sea shores and in the Wadden Sea. Very often the Barnacle Goose can be watched in large flocks on the German and Dutch North Sea coast. These geese also move to inland areas, up to 300 to 350 km from the coast line. The Barnacle Goose is a so-called marine goose and one of the species breeding in the arctic.

Characteristics of the Barnacale Goose
Taxonomy
Order: Anseriformes
Family: Anatidae
Sub-family: Swans and Geese (Anserinae)
Genus: Marine Geese (Branta)
Species: Barnacle Goose
Scientific Name: Branta leucopsis
Names and Synonyms of the Barnacle Goose
German: Weisswangengans or Nonnengans
French: Bernache nonnette
Spanish: Barnacla Cariblanca
Portuguese: Ganso-marisco
Italian: Oca facciabianca
Dutch: Brandgans
Danish: Bramgås
Swedish: Vitkindad gås
Norwegian: Hvitkinngås
Finland: Valkoposkihanhi
Iceland: Helsingi
Inuktitut: Nerlernarnaq
Greenland: Nerlernarnaq
North Karelian: Valkiepoškihanhi
North Samian: Gierdocuonji, Vilgesnierčuonjá
Polish: Bernikla białolica
Russian: Белощёкая казарка

Distribution – Movement – Wintering – Habitat
Distribution: Distributed across the northern Western Palearctic with breeding population in the arctic zones. Breeding populations on East Greeland, Svalbard, Nowaja Zemlya, Waigatsch and also with populations on Iceland. Scattered populations in northern Germany (Schleswig-Holstein and Lower Saxony), also in the Netherlands
Movement: Migratory. Migration to wintering areas begins as early as October and lasts until early November. By end-November large flocks concentrate on the Waddensea between Schleswig-Holstein and the Netherland. There are also flocks migrating to inland areas as far as 300-400 km from the coast line. Return to breeding areas begins in by April and lasts to May, sometimes even in June. Returning to the breeding habitats correlates with the snowmelt.
Wintering: Breeding populations from Greenland winter on the Western Iles (Hebrides) in northwest Scotland and in Ireland. The breeding populations from the Barents Sea winter in northwest Germany, the Netherlands and in the northwest of France. Barnacle Geese are frequent guests in the Waddensee. Further wintering areas are on Baltics coast of Sweden, Denmark and in Schleswig-Holstein
Barnacle Geese windering on the Lower Rhine in western Germany close to the Dutch border
As early in November but by mid-December at the latest, Barnacle Geese reach the marshes and grassland on both sides of the Lower Rhine in the west of Germany. Early in the morning large flocks leave the sleeping grounds and move the feeding grounds which are mainly kilometers apart. The video shows a flock of Barnacle Geese while feeding on grasslands. Check it out
Habitat: Breeding habitats are along the coastlines and in Greenland and Russia also up in adjacent moutainous areas. On Iceland also in coastal marshes. Proximity to water is essential.
Behaviour
Barnacle Geese are diurnal but also nocturnal in moonlight. Sleeping and feeding grounds are several kilometres apart. Feed on grassland. Gregarious birds during the entire year. Colonial breeders.

Field Characteristics of the Barnacle Goose
Medium-sized and fairly compact. Clearly to be indentified, cannot be mistaken for other black geese; though similar to other branta species. Thick-set short neck, rounded head. Body is rather stocky. Shows long wings in flight, bill is small. Head, neck and breast are black, with large whitisch, pale yellowish or pale buff area. Cheeks and throuat withh a variable black stipe across the lores to the eye. Underparts silver-white, upperparts grey and barred black and white. During flight difficult to recognise is the white head from a distance. Obviously strong contrast between black breast and whitish belly. Wings slightly shorter than on Brent Goose.
Bill: dark slate-grey
Iris: dark brown
Legs: dark
Measurements and Mass
Size: 58-71 cm, ♂ slightly larger than ♀
Weight:
♂ = 1400-2200 g (max. 2650 g)
♀ = 1290-1900 g
Wingspan: 132-145 cm
Wing:
♂ = 3888-429 mm
♀ = 376-410 mm

Voice
Barnacle Geese are very vocal but much less noisy than other species. Though, noisier in flocks, and especially when in flight. Call is repeated nasal gua.

Breeding
Breeding: Start of breeding correlates with the snowmelt in breeding habitats and subsequently immediately after the birds return from their wintering habitats between May and June by the latest. Small breeding colonies between up to 50 to a maximum of 150 pairs.
Sexually mature: Probably in the third year.
Mating: Probably even before maturity. Barnacle Geese arive as breeding pairs in the breeding habitat. Lifetime monogamous breeding pairs.

Clutches and Nest
Clutches per breeding season: 1 clutch per year.
Nest: Nest are on cliffs, rocky ridges and boulders, always along the coastlines and also up in mountainous areas as is the case in Grednland and Russia. Nest is scratched mould on the ground lined with plant material gathered in the surroundings of the nest. Minimum distance to other nests in colony is > 1 m.
Clutch: (2-) unsually 4-5 (rarely -9) eggs
Recurrent Clutch: no such data recorded.

Egges and Egg Measurements
Eggs: vary from elliptical to spindle shaped. Cream white shell.
Egg Measurements:
Length: 68.7-82.7 mm
Width: 46.4-53.6 mm
Fresh Egg Weight: 77-125 g (Ø n =105)
Shell Weight: 8.5-12.2 g

From Laying to Fledging and Dependency
Laying Interval: probably 24 hours
Begin of incubating: after laying the last egg
Incubation: 24-25 (max. -28) days, only ♀ is incubating but is fedd by ♂
Hatching: no recorded data; assumably all chicken hatch within 24 hours
Fledging: Within a few days parents show their goslings how to jump off the cliffs/ledges and are then brought to the water. Goslings are not fed by adults but are able to feed in green plants but are looked after by their parents. After 40-45 days the juveniles fledged.
Dependency: After fledging the juveniles still follow their parents and also migrate as family to wintering grounds.

Miscellanous
Food: Barnacle goose feed on grass, herbs, seeds, lichens and mosses, also on inscts and earthworms
Longevity: Barnacle Goose can reach an age of over 19 years. The oldest ringed bird known was 19 years and 8 month old. The minimum age is about 12 years. In captivity Barnacle Goose can reach ann age of about 40 years.
Threats and enemies: Loss of extensive and undisturbed feeding grounds. Loss of feeding grounds because of large wind energy plants in coastal areas. Human persecution because of alledged damage to fields, arctdic fox, dogs, White-tailed Eagle

References
Bauer, Hans-Günther, Bezzel, Einhard et. al. (HG), Kompendium der Vögel Mitteleuropas, Band 1, Sonderausgabe 2012, Aula Verlag, Wiebelsheim
Bauer, Hans-Günther, Bezzel, Einhard et. al. (HG), Kompendium der Vögel Mitteleuropas, Band 3, Literatur und Anhang, Aula Verlag Wiebelsheim, 2. vollständig überarbeitete Auflage 1993
Bezzel, Einhard, Kompendium der Vögel Mitteleuropas, Non-Passeriformes, Band 1, Aula Verlag Wiesbaden, 1985
Bruun/Singer/König, Der Kosmos Vogelführer, Franck’sche Verlagshandlung Stuttgart, 5. Auflage 1982
Glutz von Blotzheim, Urs et. al (HG), Handbuch der Vögel Mitteleuropas, Band 2, Anseriformes (1. Teil), Akademische Verlagsgesellschaft, Wiesbaden, 1979, Nachdruck der Auflage von 1968
Reeber, Sébastien, Wildfowl of Europe, Asia and North America, Helm Identification Guides, Christopher Helm London, 2015
Svenson, Lars et. al, Der Kosmos Vogelführer, Franck-Kosmos Verlag GmbH & Co. KG, Stuttgart, 2. Auflage 2011
Svenson, Lars et.al, Collins Bird Guide, The most complete Guide to the Birds of Britain and Europe, Harper Collins London, 2nd Edition, 2021
Uspenski, S.M. Dr. habil, Die Wildgänse Nordeurasiens, Die Neue Brehm Bücherei, Band 352, A. Ziemsen Verlag Wittenberg Lutherstadt, 1965
Bundesamt für Naturschutz: Nationaler Vogelschutzbericht 2019 gemäß Artikel 12 Vogelschutzrichtlinie, Berichtsdaten aus dem Abschnitt Wa-WE Wintergäste (pdf download)


Image Credits
Eggs of the Barnacle Goose – source: by Roger Culos – own works, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=72311032
Featured Image of the Barnacle Goose: by ©Raymond Loyal
All other post images of the Barnacle Goose: by © Raymond Loyal

