Egyptian goose

Name and taxonomy

Carl Linnaeus described the species in 1766, in the twelfth edition of Systema Naturae. He called it Anas aegyptiaca and worked partly from a French account of 1760. Mathurin Jacques Brisson had described and drawn the bird in his Ornithologie. Leonhard Stejneger introduced the modern genus Alopochen in 1885. The name means fox-goose, from the Greek words for a fox and for a goose. It refers to the ruddy colour of the back.

The species name aegyptiaca is simply the Latin for Egyptian. No subspecies are recognised, so the species is monotypic. The genus Alopochen holds two extinct island birds beside this one. Those were the sheldgeese of Mauritius and of Reunion, both now gone. English speakers sometimes call the bird the Nile goose.

Evolution and relatives

The Egyptian goose sits in the subfamily Tadorninae with the shelducks of the genus Tadorna. Like other shelducks, it stands between the true geese and the ducks in shape and habit. The heavy body and the slow flight give this species its goose-like look. That look is the reason the English name calls it a goose at all. Studies of mitochondrial DNA leave the link to Tadorna unsettled. More work is probably needed before the group is fully sorted.

The two other members of Alopochen died out after people reached their islands. The Mauritius and Reunion sheldgeese are known, as far as the record suggests, only from remains and old reports. This species is therefore the last of its genus. It is also the most widely spread member of the duck family in Africa.

Appearance

The bird is 63 to 73 cm long and weighs 1.5 to 2.3 kg. The neck is long, the legs are long and pink, and the bill is pink. A dark brown patch rings each eye, which is the clearest field mark. A second brown patch sits in the middle of the chest. The head and the upper wings are brown, and the rest of the body is a paler brown. Plumage tone varies a great deal, and some birds look grey while others look brown.

That variation follows neither sex nor age. A large part of the wing is white in a mature bird. The wing coverts hide the white when the bird rests. An alarmed or angry bird opens the wing and shows the white panel. The underside of the wing carries white and green. A young bird lacks both the eye patches and the chest patch.

The two sexes wear the same plumage, which makes them hard to tell apart. Males run somewhat larger than females. The voice appears to be the surest test, rather than the look. In flight the bird looks heavy and slow, more like a goose than a duck.

Habitat and range

The natural range runs across sub-Saharan Africa and up the Nile Valley. The bird is common to abundant over most of that ground. It has grown scarce in the northern part of the Nile Valley. It wants open or half-open country near fresh water. Rivers, streams, lakes, ponds, marshes, meadows and crop fields all suit it. It avoids thick forest and true desert.

The species reaches 4,000 metres above sea level in the Ethiopian Highlands. Outside the breeding season it wanders, sometimes north into the dry Sahel. A few birds reach Algeria and Tunisia, which were once a regular part of the range. The species bred in southeastern Europe until the early 1700s. Birds held on in Turkey and in the western Middle East as late as the early 1900s. Nobody knows why it vanished from either place.

British landowners brought the bird to estates and parks in the 17th century. Those were the first birds released anywhere outside Africa. The British list added the species formally only in 1971. It now breeds mainly in East Anglia and along the River Thames. In winter the birds spread through river valleys and feed on short grass and cereals. GBIF holds occurrence records from 107 countries.

Diet and feeding

The Egyptian goose is mainly a plant eater. It grazes young grass on grassland and savanna. It also takes grain from farmland, and wheat is a favourite. Soft leaves and other plant matter fill out the diet. Locusts, worms, insects and the odd frog make up a small animal share.

Most feeding happens on land, in pasture or in an arable field. The birds leave the water in the morning and return to it at night. Goslings cannot graze for their first few weeks. They eat small water animals instead, above all freshwater plankton. That diet carries a risk when a pond loses its oxygen. Botulinum toxin can then pass up the food chain in worms and larvae and kill a whole brood.

The parents eat almost none of those small animals, so they usually escape the poisoning. Adults feed themselves and never carry food to the young. A gosling forages for itself from the day it hatches. Farmers in southern Africa complain that flocks strip young crops. The same flocks probably remove pest insects from those fields as well.

Behaviour and social life

Outside the breeding season the birds live in small flocks. A flock gives more eyes to watch for danger, which is probably why it forms. Pairs split away from the flock to breed and rejoin it afterwards. Most birds settle on one pond, lake or river for life. They move only if a drought dries the water or predators grow too many.

Both sexes turn fiercely territorial once they start to breed. A pair chases an intruding bird into the air and attacks it there. Observers describe those chases as aerial dogfights. The birds have even attacked drones that flew over their water. A neighbouring pair may kill another pair's goslings to free up food and space. That aggression is the reason the European Union treats the species as a problem.

Communication and senses

The two sexes sound quite different, and the voice is the best way to tell them apart. A male gives a hoarse, quiet quack that he uses only when roused. He also gives a louder breathy call in a fast run of notes. That call has been likened to a steam engine. A female has a far louder and rougher quack. She uses it most in anger while she is minding her young.

For most of the year the birds are quiet and reserved. In the breeding season they turn noisy, and a stressed bird makes a great deal of sound. A courting male honks loudly, stretches his neck and spreads his feathers. The white wing panel works as a visual signal in alarm or aggression. Like other waterfowl, the birds see well and feed by sight in daylight.

Reproduction and life cycle

Both sexes are ready to breed at two years old. Most pairs breed in the spring, or else as the dry season closes. The season falls somewhere between July and March, depending on the region. A male wins his mate with a loud display of honking and posturing. Egyptian geese are monogamous, and most pairs stay together for life.

The pair nests alone in thick plants, in a hole, or flat on the ground. Holes in old trees in parkland are a favourite site. Some pairs take over the old nest of a buzzard or a magpie, high in a tree or on a ledge. The female builds with reeds, leaves, grass and feathers. A nest sits near water for safety and near grass for food.

A clutch holds five to twelve eggs. Both parents take turns to incubate for 28 to 30 days. The goslings hatch active and covered in down. The father guards the brood while the mother keeps them together. The young fly at about 70 days old. A pair raises one brood a year.

Wild birds live up to 15 years. One captive bird reached the age of 35. A zoo bird in the United States lived fourteen years. Nobody has measured a typical wild lifespan for the species.

Predators and threats

In Africa the bird faces a long list of hunters. Lions, leopards, cheetahs and hyenas all take Egyptian geese. Crocodiles take birds at the water's edge. Old World vultures take eggs and goslings. Flocking is probably the main defence, because many birds watch at once.

Botulism poisoning kills whole broods of goslings in stagnant water. Neighbouring pairs kill goslings in fights over ground and food. Drought forces birds off a lake and into unfamiliar country. Farmers in southern Africa shoot at flocks to drive them off young crops. In Great Britain the law now allows anyone to shoot a bird that causes problems. None of these pressures appears to threaten the species as a whole.

Population and conservation

The IUCN lists the Egyptian goose as Least Concern. It is the most widely spread member of its family in Africa. More dams and farm ponds in southern Africa have raised local numbers. CITES places the species on Appendix III. The conservation problem here appears to be the opposite of scarcity.

Birds released in the Netherlands in 1967 and in Belgium in 1982 founded the European population. Escapes from other collections probably added to it. The species spread into Germany and France in the mid-1980s. In the early 2000s it reached Switzerland, Luxembourg, Denmark and the Czech Republic. Single birds and odd nests have turned up in Austria, Italy, Poland, Spain and Sweden.

The United Kingdom declared the bird a non-native species in 2009. The European Union added it to the invasive species list in 2017. Member states may not import, breed, sell or release it, and must try to remove it. Breeding populations also live in Mauritius, Israel, the United Arab Emirates and the United States. American birds nest in Arkansas, California, Florida, Nebraska, Oklahoma and Texas. Releases in Australia and New Zealand failed to take hold.

Relationship with humans

People have kept this bird for its looks for a very long time. British estates stocked ornamental lakes with it from the 17th century. Dutch and Belgian collections did the same three hundred years later. Every wild European population probably began with birds that escaped a park. In Africa few people hunt the species, because it often lives far from towns.

Farmers are the main exception, and they shoot to protect sprouting crops. In European towns the bird now grazes lawns, sports pitches and park banks. Its droppings and its temper likely make it unpopular with park keepers. It drives other waterbirds off nesting islands and tree holes. That displacement is the reason for the European ban on keeping it.

In culture and myth

No wild bird appears more often in ancient Egyptian art than this one. Painters and carvers appear to have shown it on tomb walls, on panels and in hunting scenes. In ancient Egyptian religion a goose god named Gengen-Wer guarded a sky egg. The name translates as the great honker or the great cackler. The egg was said to hold the creative force that began the world. The Book of the Dead names Gengen-Wer in its fifty-ninth chapter.

Scholars long linked the earth god Geb to that creator goose. The link appears to be a mistake, born of a similar sound. The Egyptian word for the white-fronted goose meant the lame one or the stumbler. That word resembled the god's name, so a goose sign spelled it. The sign was a sound spelling and never a holy bird of Geb.

In modern Britain the bird appears to be a fixture of ornamental water and country house parks. Birdwatchers there probably argued for years over whether to count it as a wild British bird. The British list settled the question in 1971. The English name misleads, because the animal is a shelduck rather than a goose.