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Wildlife Guide · Europe & Asia

Goose

Family Anatidae (Anser and Branta)

Large, social grazing waterfowl famous for V-formation migrations

Varies; common species Least Concern (IUCN)
A greylag goose standing on a grassy riverbank, showing its stout orange bill, pale grey-brown plumage and webbed feet

Image: Source: Wikimedia Commons — “Greylag goose (Anser anser)” by Hobbyfotowiki, CC0

In brief

A goose is a large, social grazing waterfowl in the family Anatidae, split mainly into grey and white geese (Anser) and black geese (Branta). Bigger than ducks, geese feed on grass, form lifelong pair bonds and migrate long distances in energy-saving V-formations.

By the WARN Research & Conservation TeamChecked against IUCN Red List & CITES sourcesLast updated

A goose is a large, social waterfowl in the family Anatidae, grouped chiefly into the grey and white geese (genus Anser) and the black geese (genus Branta). Bigger than ducks but smaller than swans, geese are built for grazing: they crop grasses, sedges and crops with a strong, serrated bill and spend much of their time walking on land. Many species are powerfully migratory, travelling in the famous V-shaped skeins that save energy and keep the flock together. Geese form strong, long-lasting pair bonds and raise broods of downy goslings. The greylag goose (Anser anser) is the ancestor of most domestic breeds, while the Canada goose (Branta canadensis) is a familiar park resident across much of the Northern Hemisphere.

2

main genera: Anser (grey/white) and Branta (black)

1.8 m

wingspan of a large Canada goose

~2500 BCE

Domestic geese shown in Egyptian art by the Old Kingdom

10-24 yrs

typical wild lifespan of a Canada goose reaching adulthood

Figures sourced from Goose - Wikipedia, Greylag goose - Wikipedia, Canada goose - Wikipedia and other references on this page.

Goose: Quick Facts

Vital statistics and key facts about the Goose
Common name Goose (plural: geese)
Main genera Anser (grey/white) and Branta (black)
Family Anatidae (waterfowl, with ducks and swans)
Typical length About 74-110 cm, depending on species
Wingspan Roughly 1.5-1.8 m in large species
Weight Around 3-4 kg in common species
Diet Mainly grasses, leaves, grain and aquatic plants (grazer)
Migration Many species migrate in V-shaped skeins
Social life Mostly monogamous, often paired for life; flock outside breeding
Lifespan Often 10-24 years in the wild (Canada goose)

Scientific Classification

Scientific classification of the Goose
Kingdom Animalia
Phylum Chordata
Class Aves
Order Anseriformes
Family Anatidae
Subfamily Anserinae
Genera Mainly Anser (grey/white geese) and Branta (black geese)

Conservation Status

IUCN Status
Conservation status varies by species. Many of the most familiar geese, including the greylag goose (Anser anser) and the Canada goose (Branta canadensis), are assessed by the IUCN as Least Concern, with large and often increasing populations. Resident Canada geese are so numerous in places that they are widely treated as urban pests. Some more specialised or restricted-range geese, however, face pressure from wetland loss, drainage, hunting and disturbance, so not all species are equally secure.
Population
Not meaningful as a single figure; common species number in the millions, while a few specialised geese have far smaller populations.
Trend
Stable to increasing for widespread generalist species such as the greylag and Canada goose; declining for some specialised wetland geese.
Assessed
Greylag and Canada goose assessed as Least Concern in recent IUCN Red List assessments
CITES
Not generally listed; common geese are not CITES-restricted, though some specific species may have trade protections

Because goose covers many species across two main genera, status is best read species by species rather than as a single category.

Key Facts: Goose

  • Geese are large grazing waterfowl, classed mainly in the grey/white genus Anser and the black genus Branta within the duck family Anatidae.
  • They fly in V-shaped formations that conserve energy and help the flock stay in contact during long migrations.
  • Geese are largely herbivorous grazers, cropping grass, leaves, grain and aquatic plants, though they take some small invertebrates too.
  • Most pair for life and defend territory only during the short nesting season, when they raise downy goslings.
  • The greylag goose is the wild ancestor of most domestic goose breeds, kept by people for thousands of years.
  • Common species such as the greylag and Canada goose are listed as Least Concern, and resident Canada geese are often treated as urban pests.

What does a goose look like, and how is it different from a duck or swan?

Geese are medium-to-large waterfowl that sit between ducks and swans in size. A greylag goose measures roughly 74-91 cm long with a wingspan of about 147-180 cm, while a large Canada goose can reach 75-110 cm with a wingspan up to around 185 cm. They have long necks (though shorter than a swan's), heavy bodies, broad wings and webbed feet, and a stout, deep-based bill with serrated edges suited to gripping and cropping vegetation. Compared with ducks, geese are bigger, longer-necked and spend far more time grazing on land; both sexes usually share similar plumage, unlike the bright drakes of many ducks. Plumage varies by group: Anser geese tend to be grey-brown or white with pink or orange bills and legs, while Branta geese, such as the Canada and barnacle goose, are boldly patterned in black, white and grey. Swans, by contrast, are larger again, with very long necks and almost always all-white or all-black adult plumage.


Why do geese fly in a V-formation?

The V, or skein, is one of the most recognisable sights in the bird world, and it is a feat of aerodynamics. As each goose flaps, its wingtips shed swirling vortices of air; birds flying slightly behind and to the side can ride the rising part of that wake, gaining lift and reducing the effort needed to stay aloft. By trailing one another in a staggered line, the flock as a whole saves energy on long journeys. The formation also aids communication and lets every bird keep its flock-mates in view, which matters when migrations can span continents. Geese share the demanding lead position and rotate through it, and much of a migration is actually spent resting at traditional stopover sites, where birds refuel and build fat reserves before the next leg. Young geese learn these routes and stopovers from their parents, so migratory knowledge is passed down the generations rather than being purely instinctive.


What do geese eat and how do they live?

Geese are primarily herbivores and dedicated grazers. They feed chiefly on grasses, sedges, leaves, roots, aquatic plants and agricultural grain such as wheat, corn and rice, using the serrated edges of their bills to tear and crop vegetation. Some species also take small quantities of insects, molluscs, crustaceans and occasionally tiny fish, especially when feeding goslings that need protein to grow. Socially, geese are strongly bonded: most are monogamous and stay together as pairs throughout the year, becoming territorial mainly during the short nesting season. They nest on the ground near water, and both parents help guard the brood of goslings, which can walk and feed themselves soon after hatching. Outside the breeding season geese gather in large, noisy flocks, and a group has many traditional names: a gaggle on the ground, and a skein, team or wedge in flight. Their loud honking calls help coordinate these flocks and warn of danger.


Are geese endangered, or are some a nuisance?

Most familiar geese are not threatened. Widespread species such as the greylag goose and the Canada goose are assessed as Least Concern by the IUCN, with large, often increasing populations. In fact, the opposite problem is more common in towns and cities: non-migratory Canada geese, which stay put where winters are mild and predators few, are widely regarded as pests. Their droppings foul parks and waterways, they graze and trample crops and amenity grass, they can be noisily aggressive when nesting, and they readily beg for food. Management can involve hazing, egg treatment to limit breeding, and culling. Not every goose is so secure, though. Some species and local populations face pressure from habitat loss, drainage of wetlands, hunting and disturbance, and a few island or specialist geese have small ranges. The broad pattern is that adaptable, generalist geese thrive alongside people, while more specialised wetland species depend on the health of the marshes, estuaries and tundra they need.

Goose vs swan: how to tell them apart

FeatureGooseSwan
SizeMedium to largeLarger, among the biggest waterfowl
NeckLong but proportionateVery long and graceful
PlumageGrey-brown, white, or boldly black-and-whiteUsually all-white or all-black as adults
BillStout, deep-based, for grazing grassLong, with a knob or coloured base in many species
FeedingMostly grazes on landFeeds mainly in water, often up-ending
FamilyAnatidae (genera Anser, Branta)Anatidae (genus Cygnus)

What WARN Does

World Animal Rescue Network (WARN) does not run field projects specifically for wild geese, which range mainly outside the countries where our partners work. This guide is part of WARN's free educational work, helping people understand and value the wildlife around them. The threats that affect vulnerable wetland geese, above all the loss and drainage of wetlands, also harm many of the animals WARN does help to protect.

If this guide helped you see geese a little differently, a small gift helps keep WARN's free wildlife education and animal-protection work going.

How does the goose compare?

Goose: Frequently Asked Questions

What is the difference between a goose and a duck?

Geese and ducks are both in the family Anatidae, but geese are larger, with longer necks and heavier bodies. Geese are dedicated grazers that spend much of their time feeding on grass and crops on land, while many ducks feed more in water. In geese, both sexes usually look alike, unlike the often brightly coloured drakes among ducks.

What is a male goose, a female goose and a baby goose called?

A male goose is called a gander, an adult female is simply called a goose, and a young goose is a gosling. Collectively the word geese is the plural. Goslings are covered in down and can walk, swim and feed themselves within a day or so of hatching, staying close to both parents, who help guard the brood until it can fly.

Why do geese fly in a V-shape?

Flying in a V, or skein, saves energy. Each beating wing throws off swirling air, and birds positioned behind and to the side ride the rising part of that wake, gaining extra lift. The formation also helps the flock communicate and keep one another in sight on long migrations. Geese share and rotate through the tiring lead position at the point of the V.

What do geese eat?

Geese are mainly herbivores and graze on grasses, sedges, leaves, roots and aquatic plants, as well as agricultural grain such as wheat, corn and rice. They use the serrated edges of their bills to crop vegetation. Some also take small amounts of insects, molluscs and other invertebrates, particularly when feeding fast-growing goslings that need extra protein.

Are geese dangerous or aggressive?

Geese are not generally dangerous to people, but they can be aggressive, especially during the nesting season when defending a mate, nest or goslings. A defensive goose may hiss, lower its head, flap its wings and chase or nip an intruder. Such encounters are usually about warning you off rather than causing real harm. Keeping a respectful distance from nesting birds avoids most conflict.

Where do geese live?

Geese are found across much of the world, particularly in the Northern Hemisphere. Grey and white geese (genus Anser) breed widely across Europe and Asia, while black geese (genus Branta), including the Canada goose, are strongly associated with North America. Geese favour wetlands, lakes, rivers, estuaries, grasslands and farmland, and many now thrive in urban parks where food and safety are plentiful.

How long do gooses live?

Gooses typically live Often 10-24 years in the wild (Canada goose). A goose is a large, social grazing waterfowl in the family Anatidae, split mainly into grey and white geese (Anser) and black geese (Branta). Wild and captive figures can differ; use the sources listed on the guide for the underlying studies.

How big is a goose?

A Goose is about About 74-110 cm, depending on species. A goose is a large, social grazing waterfowl in the family Anatidae, split mainly into grey and white geese (Anser) and black geese (Branta).

Sources & References

Population figures, conservation status and biological facts on this page are drawn from authoritative scientific and intergovernmental sources.

Terms used on this page

Plain-English definitions, from our wildlife and conservation glossary.

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