Anser indicusbar-headed goose

Geographic Range

Bar-headed geese (Anser indicus) have a breeding range that stretches from Mongolia south through Russia and Western China to Tibet and as far west as Kyrgyzstan. Approximately 25% of the global population of bar-headed geese winter on the southern Tibetan-Qinghai Plateau. Another wintering area for a portion of the population is India and Bangladesh. (Guo-Gang, et al., 2011; Takekawa, et al., 2009)

Habitat

Bar-headed geese can be found at high elevations. They use habitats like mountain grasslands and crop fields from surrounding villages. Bar-headed geese tend to use freshwater marshes, lakes, and streams that are around elevations of 4,000 to 6,000 meters above sea level as stop-over and over-wintering sites. Some geese have even been reported to migrate at altitudes of 9,000 meters when they cross the Himalaya Mountains. (Guo-Gang, et al., 2011; Middleton, 1992; Scott, et al., 2009; Takekawa, et al., 2009)

  • Range elevation
    Sea Level to 6,000 m
    to ft

Physical Description

Bar-headed geese have grey bodies, with orange legs and a black and white neck. This species is named for the obvious black U-shaped bars on the back of the white head. They weigh between 2 and 3 kg (4.5 and 6.5 lbs) with a wingspan between 140 and 160 cm (55 and 62 inch), and are between 68 and 78 cm (27 and 30 inch) in length. Bar-headed geese have a basal metabolic rate of 756 cubic centimeters of oxygen per hour. (Tammelin, 2012; Ward, et al., 2002)

  • Sexual Dimorphism
  • sexes alike
  • Range mass
    2.0 to 3.0 kg
    4.41 to 6.61 lb
  • Range length
    68 to 78 cm
    26.77 to 30.71 in
  • Range wingspan
    140 to 160 cm
    55.12 to 62.99 in
  • Average basal metabolic rate
    756 cm3.O2/g/hr

Reproduction

Bar-headed geese are seasonal breeders. They exhibit a monogamous mating system, where males pair with one single female for several years. During times when the population is biased towards females a polygynous system is adopted where a monogamous pair may be joined by multiple secondary females. These secondary females also breed with the male of the pair. Because they breed in large colonies, females defend their nests from socially lower females that may be using brood parasitism to increase the likely hood of their offspring's survival. (Lamprecht, 1987)

Bar-headed geese typically breed on an annual basis. This occurs during the spring. Nesting occurs from the last week of April until June. They typically lay 3 to 8 eggs on average. After 28 to 30 days the goslings hatch. There was little information on the birth mass of the goslings. They then fledge by 55 to 60 days, and reach sexual maturity at 3 years of age. Bar-headed geese tend to breed on the Tibetan-Qinghai Plateau. They lay their eggs in ground nests at high elevations in the highland marshes and lakes. (Prins and van Wieren, 2004; Takekawa, et al., 2009)

  • Breeding interval
    Bar-headed geese breed annually (once yearly).
  • Breeding season
    Bar-headed geese breed in the last week of April through July.
  • Range eggs per season
    3 to 8
  • Range time to hatching
    28 to 30 days
  • Range fledging age
    55 to 60 days
  • Range time to independence
    55 to 60 days
  • Average age at sexual or reproductive maturity (female)
    3 years
  • Average age at sexual or reproductive maturity (male)
    3 years

Bar-headed geese use biparental care when raising young. Studies show that male bar-headed geese are more alert and defensive when in the presence of their goslings. These same studies show that the goslings have the added benefit of an increased survival rate from having both parents. Both parents provide their goslings with protection from predators and other geese. In addition to that the parents also protect the goslings' food. (Friedl, 1993; Schneider and Lamprecht, 1990)

Lifespan/Longevity

Little information is published on the lifespan of bar-headed geese. Like most geese they are long-lived. A close relative, greylag geese, have a lifespan of 20 years in the wild and the oldest one in captivity lived 31 years. (de Magalhaes and Costa, 2009; de Magalhaes and Costa, 2009)

  • Average lifespan
    Status: wild
    20 years
  • Average lifespan
    Status: captivity
    20 years

Behavior

This species is typical to most in the order Anseriformes in that they are a social species migrating in family groups or large colonies. They are very motile migrating twice a year over the Himalaya Mountains to and from their breeding grounds on the Tibetan-Qinghai Plateau. They migrate in "V"-formations or variations of it. They have a social hierarchy consisting of mated male-female pairs being the highest, followed by secondary females that are usually part of a harem, and lowest socially is lone females. This harem usually forms when the population is biased towards females. Bar-headed geese make ground nests with shallow depressions at high elevations. They defend these nests from predators and from other socially lower females. ("Bar-headed geese - the astronauts among migratory birds", 2011; Prins and van Wieren, 2004; Scott, et al., 2009; Speakman and Banks, 1998)

Home Range

Their Breeding range is in Western China, Mongolia, and on the Tibetan-Qinghai Plateau. Their non-breeding range is in India, Bangladesh and Nepal. (Prins and van Wieren, 2004; Schneider and Lamprecht, 1990; Scott, et al., 2009; Ward, et al., 2002)

Communication and Perception

Like most geese, bar-headed geese fly in "V"-shaped formations. When the lead bird gets tired they fall to the back of the formation and another goose takes the lead. The formation can vary from a traditional V to other shapes like "J"-shape and the echeleon shape where one arm of the "V"-shape is missing. The benefit of this style of flight is that each individual flies with reduced drag, which in turn saves them energy. They use vocal communications and visual cues to maintain their spacing while flying in these formations. This also assists them in staying in closely related family groups as they move from traditional feeding and breeding areas. Like other waterfowl they can also see in the ultraviolet spectrum of light. (Speakman and Banks, 1998)

Food Habits

Bar-headed geese generally feed on the highland grasses surrounding their lakes and streams where they nest. During other times of the year they can be found eating on agricultural crops such as corn, wheat, barley, and rice. (Akbar, et al., 2005)

  • Animal Foods
  • fish
  • insects
  • Plant Foods
  • leaves
  • roots and tubers
  • seeds, grains, and nuts

Predation

From the air the bar-headed geese are prey for sea eagles, golden eagles, crows, and ravens. On the ground the geese are preyed upon by red foxes. Some of the adaptations the geese have developed is the ability to survive at high altitudes. This limits the amount of ground predators that can reach them. They can survive at high altitudes because they have a higher density of capillaries that are spaced closer together this allows them to deliver more oxygen to their muscles, in particular their flight muscles. In addition to their capillaries they also have hemoglobin in their blood that is more efficient at taking in oxygen. Another adaptation is that these geese tend to live in large colonies or smaller family groups which enhances predator detection. (Prins and van Wieren, 2004; Scott, et al., 2009)

Ecosystem Roles

These geese are prey for animals such as red foxes, and golden eagles. Some can also be parasites by using higher ranked females as hosts to raise their offspring. In addition they are also carriers of the H5N1 virus and capable of passing the virus to humans, and other animals as well. They assist in the dispersal of grass seeds they eat throughout the year. (Cui, et al., 2011; Prins and van Wieren, 2004; Weigmann and Lamprecht, 1991)

  • Ecosystem Impact
  • disperses seeds

Economic Importance for Humans: Positive

These geese benefit humans because of ecotourism to the wildlife areas that they use as refueling stops during their migrations. "The East Calcutta Wetlands in Western Bengal (a stop over site for migrating Bar-headed Geese) has environmental benefits worth 38.54 million dollars"(Bhattacharyya et al., 2008). (Bhattacharyya, et al., 2008)

Economic Importance for Humans: Negative

Bar-headed geese were one of the first species to show signs of the H5N1 (Bird Flu) virus. In addition to carrying the virus the geese are also pests to the local villagers. Since they feed on the wheat, rice, and other crops around their roosting areas, they can cause damage to farm fields. (Cui, et al., 2011)

  • Negative Impacts
  • injures humans
    • carries human disease
  • crop pest

Conservation Status

Bar-headed geese are listed on the IUCN Red List as Least Concerned. They have no special status under the US Migratory Bird Act or on the US Federal List because there is no population living in the US. Nor are they protected under the US Endangered Species Act. CITES contains no special status for the species either. (Butchart and Symes, 2012)

Contributors

Dominick Cucinello (author), University of Wisconsin-Stevens Point, Christopher Yahnke (editor), University of Wisconsin-Stevens Point, Laura Podzikowski (editor), Special Projects.

Glossary

Palearctic

living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

World Map

acoustic

uses sound to communicate

agricultural

living in landscapes dominated by human agriculture.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

brackish water

areas with salty water, usually in coastal marshes and estuaries.

chemical

uses smells or other chemicals to communicate

colonial

used loosely to describe any group of organisms living together or in close proximity to each other - for example nesting shorebirds that live in large colonies. More specifically refers to a group of organisms in which members act as specialized subunits (a continuous, modular society) - as in clonal organisms.

dominance hierarchies

ranking system or pecking order among members of a long-term social group, where dominance status affects access to resources or mates

ecotourism

humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

female parental care

parental care is carried out by females

fertilization

union of egg and spermatozoan

folivore

an animal that mainly eats leaves.

freshwater

mainly lives in water that is not salty.

granivore

an animal that mainly eats seeds

herbivore

An animal that eats mainly plants or parts of plants.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

magnetic

(as perception channel keyword). This animal has a special ability to detect the Earth's magnetic fields.

male parental care

parental care is carried out by males

marsh

marshes are wetland areas often dominated by grasses and reeds.

migratory

makes seasonal movements between breeding and wintering grounds

monogamous

Having one mate at a time.

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oriental

found in the oriental region of the world. In other words, India and southeast Asia.

World Map

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

polygynous

having more than one female as a mate at one time

seasonal breeding

breeding is confined to a particular season

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5? N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

visual

uses sight to communicate

young precocial

young are relatively well-developed when born

References

2011. "Bar-headed geese - the astronauts among migratory birds" (On-line). Goose.org. Accessed August 08, 2012 at http://www.goose.org/englisch/bar-headed-goose.html.

Akbar, M., R. Khan, S. Mehboob, Z. Nisa. 2005. Wildlife of Border Belt Game Reserve District Narowal, Punjab, Pakistan. Pak. j. life soc. sci., 3(1-2): 13-17.

Bhattacharyya, A., S. Sen, P. Roy, A. Mazumdar. 2008. A Critical Study on Status of East Kolkata Wetlands with Special Emphasis on Water Birds as Bio-Indicator. Proceedings of Taal2007: The 12th World Lake Conference, 12: 1561-1570.

Butchart, S., A. Symes. 2012. "Anser indicus" (On-line). The IUCN Red List of Threatened Species. Accessed August 06, 2012 at http://www.iucnredlist.org/details/full/100600379/0.

Cui, P., Y. Hou, a. et.. 2011. Bird Migration and Risk for H5N1 Transsmission into Qinghai Lake, China. Vector Bome Zoonotic Dis., 11(5): 567-576. Accessed August 09, 2012 at http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3096498/?tool=pmcentrez.

Friedl, T. 1993. Intraclutch Egg-Mass Variation in Geese: Mechanism for Brood Reduction in Precocial Birds. The Auk, 110(1): 129-132. Accessed August 09, 2012 at http://library.unm.edu/sora/Auk/v110n01/p0129-p0132.pdf.

Guo-Gang, Z., L. Dong-Ping, H. Yun-Qiu, J. Hong-Xing, D. Ming, Q. Fa-Wen, L. Jun, X. Zhi, L. Feng-Shan. 2011. Migration Routes and Stop-Over Sites Determined with Satellite Tracking of Bar-Headed Geese Anser indicus Breeding at Qinghai Lake, China. Waterbirds, 34(1): 112-116. Accessed August 05, 2012 at http://www.bioone.org/doi/full/10.1675/063.034.0115.

Lamprecht, J. 1987. Female Reproductive Strategies in Bar-headed Geese (Anser indicus): Why Are Geese Monogamous?. Behavioral Ecology and Socialbiology, 21(5): 297-305. Accessed August 06, 2012 at http://www.jstor.org/stable/4600095.

Middleton, B. 1992. Habitat and Food Preferences of Greylag and Barheaded Geese Wintering in the Keoladeo National Park, India. Journal of Tropical Ecology, 8 No.2: 181-193. Accessed August 05, 2012 at http://www.jstor.org/stable/2559700.

Prins, H., S. van Wieren. 2004. Number, population structure and habitat use of bar-headed geese Aniser indicus in Ladakh (India) during the brood-rearing period. Acta Zoologica Sinica, 50(5): 738-744.

Schneider, J., J. Lamprecht. 1990. The importance of biparental care in a precoial, monogamous bird, the bar-headed goose (Aniser indicus). Behavioral Ecology and Socialbiology, 27: 415-419. Accessed August 07, 2012 at http://www.jstor.org.ezproxy.uwsp.edu/stable/pdfplus/4600500.pdf.

Scott, G., S. Egginton, J. Richards, W. Milsom. 2009. Evolution of muscle phenotype for extreme high altitude flight in the bar-headed goose. Proc Biol Sci, 276(1673): 3645-3653.

Speakman, J., D. Banks. 1998. The function of flight formations in Greylag Geese Anser anser; energy saving or orientation?. Ibis, 140: 280-287.

Takekawa, J., S. Heath, D. Douglas, W. Perry, Javed Salim, S. Newman. 2009. Geographic variation in Bar-headed Geese Anser indicus: connectivity of wintering areas and breeding grounds across a broad front. Wildfowl, 59: 100-123. Accessed August 05, 2012 at https://www.wwt.org.uk/userfiles/files/11_Takekawa_pp100_123.pdf.

Tammelin, H. 2012. "Bar-headed Goose" (On-line). NatureGate. Accessed August 09, 2012 at http://www.luontoportti.com/suomi/en/tekijat/.

Ward, S., C. Bishop, A. Woakes, P. Butler. 2002. Heart rate and the rate of oxygen consumption of flying and walking barnacle geese (Branta leucopsis) and bar-headed geese (Anser indicus). The Journal of Experimental Biology, 205: 3347–3356.

Weigmann, C., J. Lamprecht. 1991. Intraspecific nest parasitism in bar-headed geese, Anser indicus. Animal Behaviour, 41: 677-688.

de Magalhaes, J., J. Costa. 2009. A database of vertebrate longevity records and their relation to other life-history traits.. Journal of Evolutionary Biology, 22(8): 1770-1774.