Hawaiian Goose
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| Hawaiian Goose | ||||||||||||||
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 At Honolulu Zoo
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| Branta sandvicensis (Vigors, 1833) |
The Hawaiian Goose or Nēnē, Branta sandvicensis, is a species of goose endemic to the Hawaiian Islands. The official bird of the State of Hawaiʻi, the Nēnē is exclusively found in the wild on the islands of Maui, Kauaʻi and Hawaiʻi. The Nēnē gets its Hawaiian name from its soft call.
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[edit] Evolution
The Nēnē evolved from the Canada Goose (Branta canadensis), which most likely migrated to the Hawaiian islands 500,000 years ago, shortly after the island of Hawaiʻi was formed. This ancestor is the progenitor the Nēnē as well as the prehistoric Giant Hawaiʻi Goose[1] and Nēnē-nui (Branta hylobadistes). The Nēnē-nui was larger than the Nēnē, varied from flightless to flighted depending on the individual, and inhabited the island of Maui. Similar fossil geese found on Oʻahu and Kauaʻi may be of the same species. The Giant Hawaiʻi Goose was restricted to the island of Hawaiʻi and measured 1.2 metres (3.9 ft) in length with a mass of 8.6 kilograms (19 lb), making it more than four times larger than the Nēnē. It is believed that the herbivorous Giant Hawaiʻi Goose occupied the same ecological niche as the goose-like ducks known as moa-nalo, which were not present on the Big Island.[2] Based on mitochondrial DNA found in fossils, all Hawaiian geese, living and dead, are closely related to the Giant Canada Goose (B. c. maxima) and Dusky Canada Goose (B. c. occidentalis).[1]
[edit] Description
The Nēnē is a medium-sized goose at 41 centimetres (16 in) tall. Females have a mass of 1.525–2.56 kilograms (3.36–5.64 lb), while males average 1.695–3.05 kilograms (3.74–6.72 lb), 11% larger than females.[3] Adult males have a black head and hindneck, buff cheeks and heavily furrowed neck.[4] The neck has black and white diagonal stripes.[4] Aside from being smaller, the female Hawaiian Goose is similar to the male in colouration. The adult's bill, legs and feet are black. It has soft feathers under its chin. Goslings resemble the male, but are a duller brown and with less demarcation between the colours of the head and neck, and striping and barring effects are much reduced. The bill, legs and feet are the same as for the adult.[4] Its strong toes are padded and have reduced webbing, an adaptation that allows it to swiftly traverse rough terrain such as lava plains.[5]
[edit] Habitat and range
The Nēnē could at one time be found on the islands of Hawaiʻi, Maui, Kahoʻolawe, Lānaʻi, Molokaʻi, and Kauaʻi. Today, its range is restricted to Hawaiʻi, Maui, Molokaʻi, and Kauaʻi. The Nēnē is an inhabitant of shrubland, grassland, coastal dunes, and lava plains, and related anthropogenic habitats such as pasture and golf courses from sea level to as much as 2,400 metres (7,900 ft).[6] Some populations migrated between lowland breeding grounds and montane foraging areas.[5]
[edit] Breeding
The breeding season of the Nēnē, from August to April, is longer than that of any other goose;[7] most eggs are laid between November and January.[3] Unlike most other waterfowl, the Nēnē mates on land.[4] Nests are built by females on a site of their choosing, in which one to five eggs are laid (average is three on Maui and Hawaiʻi, four on Kauaʻi). Females incubate the eggs for 29 to 32 days, while the male acts as a sentry. Goslings are precocial, able to feed on their own; they remain with their parents until the following breeding season.[3]
[edit] Diet
The Nēnē is an herbivore that will either graze or browse depending on the availability of vegetation. Food items include the leaves, seeds, fruit, and flowers of grasses and shrubs.[6]
[edit] Conservation
This is the world's rarest goose.[citation needed] The bird was once believed to be common, with approximately 25,000 Nēnē living in Hawaiʻi when Captain James Cook arrived in 1778.[4] However, hunting and introduced predators, such as Small Asian Mongooses, pigs, and cats, reduced the population to 30 birds by 1952.[4] However, this species breeds well in captivity, and has been successfully re-introduced; in 2004 it was estimated that there were 800 birds in the wild, as well as 1000 in wildfowl collections and zoos.[4] However, there is some concern of inbreeding due to the small initial population of birds. The nature reserve WWT Slimbridge in England was instrumental in the successful breeding of Nēnē geese in captivity. Under the direction of the leading conservationist Sir Peter Scott, it was bred back from the brink of extinction during the 1950s for later re-introduction into the wild in Hawaiʻi. There are still Nēnē at Slimbridge today. At WWT Martin Mere, they are very friendly and will eat grain out of one's hand
[edit] Gallery
 The distinctive neck pattern |
 A group of Nēnē; the bird on the right shows the characteristic foot |
 A sign in Hawaiʻi warning of crossing Nēnē. |
 Two Nēnē at the Kīlauea Point National Wildlife Refuge. |
 Three Nēnē in Liliuokalani Park and Gardens, Hilo, Hawaiʻi. |
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[edit] References
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Wikimedia Commons has media related to: Branta sandvicensis |
- ^ a b Harder, Ben (2002-02-06). "State Bird of Hawaii Unmasked as Canadian". National Geographic News (National Geographic Society). http://news.nationalgeographic.com/news/2002/02/0206_020206_canadiangeese_2.html. Retrieved on 2009-03-17.
- ^ Ziegler, Alan C. (2002). Hawaiian Natural History, Ecology, and Evolution. University of Hawaiʻi Press. p. 260. ISBN 9780824821906. http://books.google.com/books?id=l56J_8teG58C&client=firefox-a.
- ^ a b c Reading, Richard P.; Brian Miller (2000). Endangered animals: A Reference Guide to Conflicting Issues. Greenwood Publishing Group. pp. 142-146. ISBN 9780313308161. http://books.google.com/books?id=f_AWCtX29-kC&client=firefox-a.
- ^ a b c d e f g Ellis, Richard (2004). No Turning Back: The Life and Death of Animal Species. New York City: Harper Perennial. pp. 280-281. ISBN 0-06-055804-0.
- ^ a b Banko, Paul C.; Jeffrey M. Black; Winston E. Banko (1999). "Hawaiian Goose (Branta sandvicensis)". in A. Poole. Birds of North America Online. Cornell Laboratory of Ornithology. http://bna.birds.cornell.edu/bna/species/434/articles/introduction. Retrieved on 2009-03-18.
- ^ a b "Nene or Hawaiian Goose" (PDF). State of Hawaiʻi. 2005-03-25. http://www.state.hi.us/dlnr/dofaw/cwcs/files/3.29.05%20Fact%20Sheets/Nene.pdf. Retrieved on 2009-03-18.
- ^ "Hawaiian Goose (Branta sandvicensis)". Audubon Watchlist. National Audubon Society. http://audubon2.org/watchlist/viewSpecies.jsp?id=100. Retrieved on 2009-03-18.
- BirdLife International (2004). Branta sandvicensis. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 11 May 2006. Database entry includes justification for why this species is vulnerable
[edit] External links
- BirdLife Species Factsheet.
- Nene Video Clip
- "Nene or Hawaiian Goose" (PDF). State of Hawaiʻi. 2005-03-25. http://www.state.hi.us/dlnr/dofaw/cwcs/files/3.29.05%20Fact%20Sheets/Nene.pdf.
