The Gadwall (Anas strepera) is a slim duck and is a dabbling duck. It is slighly smaller than the Mallard and not as noisy. We find the mallard in the temperate zones of continental Eurasia where the bird also settles in steppe and desert zones. Though, meanwile the Gadwall also distributes in more oceanic zones from the more distant Iceland to south Scandinavia, Central Europe and more eastwards to Central Asia.
Distribution of the Gadwall in Central Europe is more patchy and it is by far not as common as the Mallard or even the Teal. During winter we notice more migrants and winter guest coming down from the north, spending winter in Central Europe. Some of the migrants even move as far southwards as the Alpine foothills.
Watching and photographing the Gadwall
Although Gadwalls are more shy than Mallards, it is well possible to watch and photograph them on close-range distances. Just keep stum and do a bit on your camouflage. For photographers, still using an EF 600 mm f4, possibly extended with Extender 1.4 or 2.0 might be essential. Everything below 500 mm focal length makes no sense at all.
Characteristics of the Gadwall
Order: Ducks and Geese (Anseriformes)
Family: Ducks (Anatidae)
Sub-family: Ducks (Anatinae)
Genus: Dabbling Ducks / True Ducks (Anas)
Scientific Name: Anas strepera
Names and Synonyms of the Gadwall
French: Canard chipeau
Spanish: Ánade Friso
Czech: Kopřivka obecná
Slovak: Kačica chripľavka
Hungarian: Kendermagos réce
Croat: Patka Kreketaljka
Russian: Серая утка
Mongolian: Бор нугас, Бордуу нугас, халбага нугас, халбагат нугас
Chinese (traditional): 漈鳧, 赤膀鴨, 青邊仔
Chinese: 漈凫, 赤膀鴨, 赤膀鸭, 青边仔
Distribution – Movements – Wintering – Habitat
Distribution: The Gadwall is a breeding bird across the temperate lowlands of the continental Eurasia. Though it also distributes in small pockets on Iceland, in Southern Scandinavia and in most of central and eastern Europe. Beyond the Ural we find the Gadwall eastwards to Central Asia and in patchy populations distributed even in Manchuria, on Sakhalin and in isolated populations in North America.
The European distribution of sedentary populations centres on Iceland, South England, Belgium, the Netherlands, Luxembourg, France, Spain, southern Europe and Germany. Migratory populations are to be found in southern Scandinavia, Denmark, eastern Germany, eastern Europe (Poland, Romania, Ukraine, Russia, Belarus and Baltic states, Estonia, Lithuania and Latvia).
Movements: The migratory populations move southwards during winter which is the case with all northern and eastern Eurasian populations. Sedentary populations leave the usual habitat in case of unexpected frosty periods and return as soon as possible.
Wintering: The main European wintering grounds of the Gadwall are in Ireland, South England, Black Sea and Caspi area, Greece, Turkey, Valley of the Nile and even as far as East Africa. Sightings of Gadwalls were recorded for Nigeria, Upper Volta and Chad.
Habitat: usually on and near shallow, stagnant or slow flowing eutrophic bodies of water. Occasionally also on coastal brackish waters. During migration and winter Gadwalls will stop at similar habitats.
Behaviour of the Gadwall
Gadwalls are mainly diurnal but are also nocturnal, depending on the availabilty of suitable food, but also in case of disturbances during daylight. They are mainly surface feeders and to a lesser extend ground feed as Mallards do. Ground feeding never goes beyond depths of about 18 inches or about 45 to 50 cm. Kleptoparasitism is not unknown for Gadwalls, food is taken away from diving birds such as the Common Coot.
Gadwalls are gergarious birds and enjoy the company of larger flocks. Though, they do not mix with other species.
Field Characteristics of the Gadwall
Slim duck, slightly smaller than Mallard and also with narrower wings and body. The Gadwall shows a whitish belly in flight. A prominent identification feature is the white spekulum in the wing of the adult ♂, which can also be seen, though smaller, with the adult ♀ and at times even on juvenile individuals.
The adult ♂ breeding plumage: head in medium brown, black stern, tail pale brown, with rest of the body in grey which shows a fine verniculated markings, most promient on the breast. Pale-grey buff. In flight black and chestnut colours on upperwing. Visible white speculum.
Adult ♀: resembles female Mallard, though with whitish belly and only small speculum. Tail feathers dark brown.
Bill: ♂ = grey-black; bill pattern with orange even stripe along cutting edge.
Measurements and Voice
Size: 46-58 cm
Weight: 550-1100 g
♂ = 990 g on average
♀ = 880 g on average
Wingspan: 84-95 cm
♂ = 261-282 mm
♀ = 243-261 mm
Voice: Different calls from ♂ and ♀. Male utters a low, short croaking “ahrk”. During courtship male also sounds a high-pitched wistling “pee”. Like other dabbling ducks, the female utters a quacking call similar to the Mallard ♀ but that call sounds harder. Gadwalls are, by far, not as noisy and chatty as Mallards.
Sexually Mature: towards the end of the first year
Mating: Monogamous breeding pair. After loss of clutch during early days, female mostly mates with another male.
Clutches per breeding season: 1 clutch per season
Breeding Season: First eggs are laid from early April from end-April to early May, but no later than early July.
Nest: nest mainly on dry ground, hidden in dense vegetation and close to water. The edge of the nest is surrounded by a wall of plant material, built by ♀ about 1-2 days before laying begins.
Clutches, Eggs & Measurements
Clutch: (6-) usually 8-12 (max -13) eggs; larger clutches are from 2 or more females.
Recurrent Clutch: only if loss of clutch happens during early days of incubation.
Eggs: long-oval cream-coloured shell without stains.
Length: 45.1-59-9 mm
Width: 33.5-43.5 mm
Ø: 53.8×38.2 mm
Weight of fresh egg: 39.8-43.8 g; Ø = 42 g
Shell weight: 2.98-4.22 g; 3.45 g
Laying, Incubation, Fledging and Dependency
Laying Interval: 2 days
Begin of Incubation: after laying the last egg
Incubation: 24-26 days, only ♀ is incubating
Hatching: first clutches hatch from early May; mainly in June and July, latest by early August. All ducklings of a clutch hatch within a day.
Fledging: Ducklings leave the nest as soon as downs are dry and follow the female. Male do not look after the flock. Juveniles fledge after 45-50 days. The female mostly leaves the juveniles days before fledging.
Dependency: After fledging all family ties are cut and juveniles are fully independent.
Food – Diet: Mainly plant-based. Animal diet supplements the normal food during summer halfyear.
Longevity: Gadwalls can reach an age of 13 years.
Mortality: 37 per cent of the ducklings die within the first three weeks.
Enemies and Threats: Pikes, Otter, Red Kite and White-tailed Eagle
Bauer, Hans-Günther, Bezzel, Einhard et. al. (HG), Kompendium der Vögel Mitteleuropas, Band 1+2, 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 3, Anseriformes (2. Teil), Akademische Verlagsgesellschaft, Wiesbaden, 1969
Reeber, Sébastien, Wildfowl of Europe, Asia, and North America, Helm Identification Guides, Bloomsbury Publishing Plc, 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 to the Birds of Britain and Europe, Harper Collins London, 2019
Bundesamt für Naturschutz: Nationaler Vogelschutzbericht 2019 – Krickente = Teal – report section Rot … Sch – breeding birds (pdf Download – text in German)
Featured Image of a Gadwall: by ©Raymond Loyal
Eggs of Gadwall: by Klaus Rassinger und Gerhard Cammerer, Museum Wiesbaden – own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=35760497
All other post images of Gadwalls: by ©Raymond Loyal