Gadwall
Encyclopedia
The Gadwall is a common and widespread duck
of the family Anatidae
.
The Gadwall is 46–56 cm (18–22 in) long with a 78–90 cm (31–35 in) wingspan. The male is slightly larger than the female, weighing on average 990 g (35 oz) against her 850 g (30 oz). The breeding male is patterned grey, with a black rear end, light chestnut wings, and a brilliant white speculum
, obvious in flight or at rest. In non-breeding (eclipse) plumage, the drake looks more like the female, but retains the male wing pattern, and is usually greyer above and has less orange on the bill.
The female is light brown, with plumage much like a female Mallard
. It can be distinguished from that species by the dark orange-edged bill, smaller size, the white speculum
, and white belly. Both sexes go through two moults annually, following a juvenile moult.
The Gadwall is a quieter duck, except during its courtship display
. Females give a call similar to the quack of a female Mallard but higher-pitched, transcribed as gag-ag-ag-ag. Males give a grunt, transcribed as nheck, and a whistle.
and Asia
, and central North America
. In North America, its breeding range lies along the Saint Lawrence River
, through the Great Lakes
, Alberta
, Saskatchewan
, the Dakotas, south to Kansas
, west to California
, and along coastal Pacific Canada
and southern coastal Alaska
. The range of this bird appears to be expanding into eastern North America. This dabbling duck is strongly migratory
, and winters farther south than its breeding range, from coastal Alaska
, south into Central America
, and east into Idaho
, Kansas
, Ohio
, Virginia
, and then south all the way into Central America. Its conservation status is Least Concern
.
In Great Britain
, the Gadwall is a scarce-breeding bird and winter visitor, though its population has increased in recent years. It is likely that its expansion was partly through introduction, mainly to England, and partly through colonization to Great Britain
, with continental birds staying to breed in Scotland
. It has been reported in the River Avon in Hampshire
. In Ireland
a small breeding population has recently become established, centred on Wexford
in the south and Lough Neagh
in the north.
The Gadwall is a bird of open wetlands, such as prairie
or steppe
lakes, wet grassland or marshes with dense fringing vegetation, and usually feeds by dabbling for plant food with head submerged. It nests on the ground, often some distance from water. It is not as gregarious as some dabbling ducks outside the breeding season and tends to form only small flocks. This is a fairly quiet species; the male has a hoarse whistling call, and the female has a Mallard-like quack. The young birds are fed insect
s at first; adults also eat some molluscs and insects during the nesting season. The Gadwall is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA
) applies.
in his Systema naturae in 1758 under its current scientific name.
The Gadwall's closest relative within the genus Anas is the Falcated Duck
, followed by the wigeon
s.
There are two subspecies although one is extinct:
The etymology
of the word Gadwall is not known but the term has been recorded in usage from 1666.
Duck
Duck is the common name for a large number of species in the Anatidae family of birds, which also includes swans and geese. The ducks are divided among several subfamilies in the Anatidae family; they do not represent a monophyletic group but a form taxon, since swans and geese are not considered...
of the family Anatidae
Anatidae
Anatidae is the biological family of birds that includes ducks, geese and swans. The family has a cosmopolitan distribution, occurring on all the world's continents except Antarctica and on most of the world's islands and island groups...
.
Description
Speculum feathers
The speculum is a patch, often distinctly coloured, on the inner remiges of some birds.Examples of the colour of the speculum in a number of ducks are:* Common Teal and Green-winged Teal: Iridescent green edged with buff....
, obvious in flight or at rest. In non-breeding (eclipse) plumage, the drake looks more like the female, but retains the male wing pattern, and is usually greyer above and has less orange on the bill.
The female is light brown, with plumage much like a female Mallard
Mallard
The Mallard , or Wild Duck , is a dabbling duck which breeds throughout the temperate and subtropical Americas, Europe, Asia, and North Africa, and has been introduced to New Zealand and Australia....
. It can be distinguished from that species by the dark orange-edged bill, smaller size, the white speculum
Speculum feathers
The speculum is a patch, often distinctly coloured, on the inner remiges of some birds.Examples of the colour of the speculum in a number of ducks are:* Common Teal and Green-winged Teal: Iridescent green edged with buff....
, and white belly. Both sexes go through two moults annually, following a juvenile moult.
The Gadwall is a quieter duck, except during its courtship display
Courtship display
Courtship display is a special, sometimes ritualised, set of behaviours which some animals perform as part of courtship. Courtship behaviours can include special calls, postures, and movements, and may involve special plumage, bright colours or other ornamentation. A good example is the 'dancing'...
. Females give a call similar to the quack of a female Mallard but higher-pitched, transcribed as gag-ag-ag-ag. Males give a grunt, transcribed as nheck, and a whistle.
Distribution
The Gadwall breeds in the northern areas of EuropeEurope
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
and Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
, and central North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
. In North America, its breeding range lies along the Saint Lawrence River
Saint Lawrence River
The Saint Lawrence is a large river flowing approximately from southwest to northeast in the middle latitudes of North America, connecting the Great Lakes with the Atlantic Ocean. It is the primary drainage conveyor of the Great Lakes Basin...
, through the Great Lakes
Great Lakes
The Great Lakes are a collection of freshwater lakes located in northeastern North America, on the Canada – United States border. Consisting of Lakes Superior, Michigan, Huron, Erie, and Ontario, they form the largest group of freshwater lakes on Earth by total surface, coming in second by volume...
, Alberta
Alberta
Alberta is a province of Canada. It had an estimated population of 3.7 million in 2010 making it the most populous of Canada's three prairie provinces...
, Saskatchewan
Saskatchewan
Saskatchewan is a prairie province in Canada, which has an area of . Saskatchewan is bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, and on the south by the U.S. states of Montana and North Dakota....
, the Dakotas, south to Kansas
Kansas
Kansas is a US state located in the Midwestern United States. It is named after the Kansas River which flows through it, which in turn was named after the Kansa Native American tribe, which inhabited the area. The tribe's name is often said to mean "people of the wind" or "people of the south...
, west to California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
, and along coastal Pacific Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
and southern coastal Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
. The range of this bird appears to be expanding into eastern North America. This dabbling duck is strongly migratory
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
, and winters farther south than its breeding range, from coastal Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
, south into Central America
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...
, and east into Idaho
Idaho
Idaho is a state in the Rocky Mountain area of the United States. The state's largest city and capital is Boise. Residents are called "Idahoans". Idaho was admitted to the Union on July 3, 1890, as the 43rd state....
, Kansas
Kansas
Kansas is a US state located in the Midwestern United States. It is named after the Kansas River which flows through it, which in turn was named after the Kansa Native American tribe, which inhabited the area. The tribe's name is often said to mean "people of the wind" or "people of the south...
, Ohio
Ohio
Ohio is a Midwestern state in the United States. The 34th largest state by area in the U.S.,it is the 7th‑most populous with over 11.5 million residents, containing several major American cities and seven metropolitan areas with populations of 500,000 or more.The state's capital is Columbus...
, Virginia
Virginia
The Commonwealth of Virginia , is a U.S. state on the Atlantic Coast of the Southern United States. Virginia is nicknamed the "Old Dominion" and sometimes the "Mother of Presidents" after the eight U.S. presidents born there...
, and then south all the way into Central America. Its conservation status is Least Concern
Least Concern
Least Concern is an IUCN category assigned to extant taxon or lower taxa which have been evaluated but do not qualify for any other category. As such they do not qualify as threatened, Near Threatened, or Conservation Dependent...
.
In Great Britain
Great Britain
Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...
, the Gadwall is a scarce-breeding bird and winter visitor, though its population has increased in recent years. It is likely that its expansion was partly through introduction, mainly to England, and partly through colonization to Great Britain
Great Britain
Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...
, with continental birds staying to breed in Scotland
Scotland
Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...
. It has been reported in the River Avon in Hampshire
Hampshire
Hampshire is a county on the southern coast of England in the United Kingdom. The county town of Hampshire is Winchester, a historic cathedral city that was once the capital of England. Hampshire is notable for housing the original birthplaces of the Royal Navy, British Army, and Royal Air Force...
. In Ireland
Ireland
Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...
a small breeding population has recently become established, centred on Wexford
Wexford
Wexford is the county town of County Wexford, Ireland. It is situated near the southeastern corner of Ireland, close to Rosslare Europort. The town is connected to Dublin via the M11/N11 National Primary Route, and the national rail network...
in the south and Lough Neagh
Lough Neagh
Lough Neagh, sometimes Loch Neagh, is a large freshwater lake in Northern Ireland. Its name comes .-Geography:With an area of , it is the largest lake in the British Isles and ranks among the forty largest lakes of Europe. Located twenty miles to the west of Belfast, it is approximately twenty...
in the north.
Behaviour
Prairie
Prairies are considered part of the temperate grasslands, savannas, and shrublands biome by ecologists, based on similar temperate climates, moderate rainfall, and grasses, herbs, and shrubs, rather than trees, as the dominant vegetation type...
or steppe
Steppe
In physical geography, steppe is an ecoregion, in the montane grasslands and shrublands and temperate grasslands, savannas, and shrublands biomes, characterized by grassland plains without trees apart from those near rivers and lakes...
lakes, wet grassland or marshes with dense fringing vegetation, and usually feeds by dabbling for plant food with head submerged. It nests on the ground, often some distance from water. It is not as gregarious as some dabbling ducks outside the breeding season and tends to form only small flocks. This is a fairly quiet species; the male has a hoarse whistling call, and the female has a Mallard-like quack. The young birds are fed insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
s at first; adults also eat some molluscs and insects during the nesting season. The Gadwall is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA
AEWA
The Agreement on the Conservation of African-Eurasian Migratory Waterbirds is the largest of its kind developed so far under the Bonn Convention. It was concluded on 16 June 1995 at The Hague, the Netherlands and entered into force on 1 November 1999 after the required number of at least fourteen...
) applies.
Taxonomy
This species was first described by LinnaeusCarolus Linnaeus
Carl Linnaeus , also known after his ennoblement as , was a Swedish botanist, physician, and zoologist, who laid the foundations for the modern scheme of binomial nomenclature. He is known as the father of modern taxonomy, and is also considered one of the fathers of modern ecology...
in his Systema naturae in 1758 under its current scientific name.
The Gadwall's closest relative within the genus Anas is the Falcated Duck
Falcated Duck
The Falcated Duck or Falcated Teal is a Gadwall-sized dabbling duck.-Distribution and habitat:The Falcated duck breeds in eastern Asia...
, followed by the wigeon
Wigeon
The Eurasian Wigeon, also known as Widgeon or Eurasian Widgeon is one of three species of wigeon in the dabbling duck genus Anas. It is common and widespread within its range...
s.
There are two subspecies although one is extinct:
- A. strepera strepera, Common Gadwall the nominate subspecies.
- A. strepera couesi, Coues' Gadwall, extinct circa 1874, was located on Fanning IslandTabuaeranTabuaeran, also known as Fanning Island or Fanning Atoll is one of the Line Islands of the central Pacific Ocean, and part of Kiribati. It is an atoll located at...
.
The etymology
Etymology
Etymology is the study of the history of words, their origins, and how their form and meaning have changed over time.For languages with a long written history, etymologists make use of texts in these languages and texts about the languages to gather knowledge about how words were used during...
of the word Gadwall is not known but the term has been recorded in usage from 1666.
External links
- BirdLife Species Factsheet
- RSPB A to Z of UK Birds Page
- An article and photograph
- Gadwall Information and Photos - South Dakota Birds and Birding
- Gadwall Information - Cornell Lab of Ornithology
- Gadwall - USGS Patuxent Bird Identification InfoCenter
- Massachusetts Breeding Bird Atlas
- Gadwall videos, photos & sounds on the Internet Bird Collection