18-529: Angel wing , also known as airplane wing , slipped wing , crooked wing , and drooped wing , is a syndrome that affects primarily aquatic birds, such as geese and ducks , in which the last joint of the wing is twisted with the wing feathers pointing out laterally, instead of lying against the body. Males develop it more frequently than females. It has also been reported in goshawks , bustard chicks, and psittacine birds ( budgerigars , macaws , and conures ). The theoretical causes of angel wing are genetics,
36-406: A characteristic upperwing coloration in flight: the tertiary remiges form a green speculum , the secondaries and primaries are black, and the coverts (forewing) are white. Their diet consists of small shore animals ( winkles , crabs etc.) as well as grasses and other plants. They were originally known as " sheldrakes ", which remained the most common name until the late 19th century. The word
54-436: A female one (the latter referring to a male). Young birds before fledging are called goslings . The collective noun for a group of geese on the ground is a gaggle ; when in flight, they are called a skein , a team , or a wedge ; when flying close together, they are called a plump . The word "goose" is a direct descendant of Proto-Indo-European *ǵʰh₂éns . In Germanic languages , the root gave Old English gōs with
72-502: A half meters tall and weighed about 22 kilograms. The evidence suggests the bird was flightless, unlike modern geese. Most goose species are migratory, though populations of Canada geese living near human developments may remain in a locality year-round. These 'resident' geese, found primarily in the eastern United States, may migrate only short distances, or not at all, if they have adequate food supply and access to open water. Migratory geese may use several environmental cues in timing
90-599: Is spent at perennial stopover sites, where individuals rest and build up fat stores for further travel. Geese, like other birds, fly in a V formation . This formation helps to conserve energy in flight, and aids in communication and monitoring of flock mates. Using great white pelicans as a model species, researchers showed that flying in a V formation increased the aerodynamics of trailing birds, thus requiring fewer wing flaps to stay aloft and lowering individuals' heartrates. Leading geese switch positions on longer flights to allow for multiple individuals to gain benefits from
108-537: Is still sometimes used to refer to a male shelduck and can also occasionally refer to the canvasback ( Aythya valisineria ) of North America. The genus Tadorna was introduced by the German zoologist Friedrich Boie in 1822. The type species is the common shelduck . The genus name comes from the French name Tadorne for the common shelduck. It may originally derive from Celtic roots meaning "pied waterfowl", essentially
126-558: The Hawaiian Islands . Geese are monogamous , living in permanent pairs throughout the year; however, unlike most other permanently monogamous animals, they are territorial only during the short nesting season. Paired geese are more dominant and feed more, two factors that result in more young. Goose fossils have been found ranging from 10 to 12 million years ago (Middle Miocene). Garganornis ballmanni from Late Miocene (~ 6-9 Ma) of Gargano region of central Italy, stood one and
144-551: The genera Anser (grey geese and white geese) and Branta (black geese). Some members of the Tadorninae subfamily (e.g., Egyptian goose , Orinoco goose ) are commonly called geese, but are not considered "true geese" taxonomically. More distantly related members of the family Anatidae are swans , most of which are larger than true geese, and ducks , which are smaller. The term "goose" may refer to such bird of either sex, but when paired with " gander ", refers specifically to
162-578: The greylag goose and snow goose , and Branta , black geese, such as the Canada goose . Two genera of geese are only tentatively placed in the Anserinae; they may belong to the shelducks or form a subfamily on their own: Cereopsis , the Cape Barren goose, and Cnemiornis , the prehistoric New Zealand goose . Either these or, more probably, the goose-like coscoroba swan is the closest living relative of
180-455: The Egyptian goose were found to be poorly resolved by mtDNA cytochrome b sequence data; this genus may thus be paraphyletic . The Radjah sheduck, formerly placed in the genus Tadorna , is now placed in its own monotypic genus: Fossil bones from Dorkovo ( Bulgaria ) described as Balcanas pliocaenica may actually belong to this genus. They have even been proposed to be referable to
198-445: The beginning of their migration, including temperature, predation threat, and food availability. Like all migratory birds, geese exhibit an ability to navigate using an internal compass, using a combination of innate and learned behaviors. The preferred direction of migration is heritable, and birds appear to orient themselves using Earth's magnetic field. Migrations occur over the course of several weeks, and up to 85% of migration time
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#1732873425385216-722: The common shelduck, but their Early Pliocene age makes this rather unlikely. Based on the Taxonomy in Flux from John Boyd's website. Radjah radjah (Lesson 1828) Reichenbach 1852 (Radjah shelduck) Alopochen Stejneger 1885 ?† T. cristata (Kuroda 1917) (Crested shelduck) T. tadorna (Linnaeus 1758) (Common shelduck) T. cana (Gmelin 1789) (South African shelduck) T. ferruginea (Pallas 1764) (Ruddy shelduck) T. tadornoides (Jardine & Selby 1828) (Australian shelduck) T. variegata (Gmelin 1789) (Paradise shelduck) The following table
234-428: The excessive intake of carbohydrates and proteins, together with insufficient intake of vitamin E, low dietary calcium and manganese deficiency. However, scientific studies have not proven any link between bread and angel wing, and some experts and academics deny the connection. Goose A goose ( pl. : geese ) is a bird of any of several waterfowl species in the family Anatidae . This group comprises
252-679: The genus Tadorna (except for the Radjah shelduck , which is now found in its own monotypic genus Radjah ), are a group of large birds in the Tadorninae subfamily of the Anatidae , the biological family that includes the ducks and most duck-like waterfowl such as the geese and swans . Shelducks are a group of large, often semi-terrestrial waterfowl, which can be seen as intermediate between geese ( Anserinae ) and ducks . They are mid-sized (some 50–60 cm) Old World waterfowl. The sexes are colored slightly differently in most species, and all have
270-640: The less energy-intensive trailing positions; in family groups, parental birds almost always lead. Some mainly Southern Hemisphere birds are called "geese", most of which belong to the shelduck subfamily Tadorninae . These are: Others: The oldest collection of Medieval Icelandic laws is known as "Grágás" ; i.e., the Gray Goose Laws . Various etymologies were offered for that name: Shelduck T. ferruginea T. cana T. tadornoides T. variegata T. cristata T. tadorna see text The shelducks , most species of which are found in
288-840: The plural gēs and gandra (becoming Modern English goose, geese, gander, respectively), West Frisian goes , gies and guoske , Dutch : gans , New High German Gans , Gänse , and Ganter , and Old Norse gās and gæslingr , whence English gosling . This term also gave Lithuanian : žąsìs , Irish : gé (goose, from Old Irish géiss ), Hindi: कलहंस, Latin : anser , Spanish and Portuguese : ganso , Ancient Greek : χήν ( khēn ), Albanian : gatë ( swans ), Finnish : hanhi , Avestan zāō , Polish : gęś , Romanian : gâscă / gânsac , Ukrainian : гуска / гусак ( huska / husak ), Russian : гусыня / гусь ( gusyna / gus ), Czech : husa , and Persian : غاز ( ghāz ). The two living genera of true geese are: Anser , grey geese and white geese, such as
306-704: The same as the English "shelduck". A group of them is called a "dopping," taken from the Harley Manuscript . The namesake genus of the Tadorninae, Tadorna is very close to the Egyptian goose and its extinct relatives from the Madagascar region, Alopochen . While the classical shelducks form a group that is obviously monophyletic , the interrelationships of these, the aberrant common and especially Radjah sheducks, and
324-631: The true geese. Fossils of true geese are hard to assign to genus; all that can be said is that their fossil record, particularly in North America , is dense and comprehensively documents many different species of true geese that have been around since about 10 million years ago in the Miocene . The aptly named Anser atavus (meaning "progenitor goose") from some 12 million years ago had even more plesiomorphies in common with swans. In addition, some goose-like birds are known from subfossil remains found on
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