Little penguin

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For the extinct penguin genus, see Korora. For the Korora Linux operating system, see Korora (operating system).
Little penguin
Eudyptula minor Bruny 1.jpg
Near burrow at night, Bruny Island, Tasmania, Australia
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Sphenisciformes
Family: Spheniscidae
Genus: Eudyptula
Species: E. minor
Binomial name
Eudyptula minor
(J.R.Forster, 1781)

The Little penguin (Eudyptula minor) is the smallest species of penguin. It grows to an average of 33 cm (13 in) in height and 43 cm (17 in) in length, though specific measurements vary by subspecies.[2][3] It is found on the coastlines of southern Australia and New Zealand, with possible records from Chile.oIn Australia, they are have been historically referred to as fairy penguins. In New Zealand, they are more commonly known as Little blue penguins or Blue penguins, owing to their slate-blue plumage. They are also known by their Māori name: kororā.

Taxonomy[edit]

The little penguin was first described by German naturalist Johann Reinhold Forster in 1781. There are several subspecies but a precise classification of these is still a matter of dispute. The holotypes of the subspecies Eudyptula minor variabilis[4] and Eudyptula minor chathamensis[5] are in the collection of the Museum of New Zealand Te Papa Tongarewa. The white-flippered penguin is sometimes considered a subspecies, sometimes a distinct species, and sometimes a morph. As the Australian and Otago (southeastern coast of South Island) little penguins may be a distinct species[6] to which the specific name minor would apply, the white-flippered birds indeed belong to a distinct species, although not exactly as originally assumed.

Mitochondrial and nuclear DNA evidence suggests the split between Eudyptula and Spheniscus occurred around 25 million years ago, with the ancestors of the white-flippered and little penguins diverging about 2.7 million years ago.[7]

Description[edit]

Little penguin at the Melbourne Zoo

Like those of all penguins, the little penguin's wings have developed into flippers used for swimming. The little penguin typically grows to between 30 and 33 cm (12 to 13 inches) tall and usually weighs about 1.5 kilogram on average (3.3 pounds). The head and upperparts are blue in colour, with slate-grey ear coverts fading to white underneath, from the chin to the belly. The flippers are blue. The dark grey-black beak is 3–4 cm long, the irises pale silvery- or bluish-grey or hazel, and the feet pink above with black soles and webbing. An immature individual will have a shorter bill and lighter upperparts.[8]

Like most seabirds, they have a long lifespan. The average for the species is 6.5 years, but flipper ringing experiments show in very exceptional cases up to 25 years in captivity.[9]

Distribution and habitat[edit]

The little penguin breeds along the entire coastline of New Zealand, the Chatham Islands, and southern Australia (including roughly 20,000 pairs[10] on Babel Island). Australian colonies exist in New South Wales, Victoria, Tasmania, South Australia and Western Australia. Little penguins have also been reported from Chile (where they are known as Pingüino pequeño or Pingüino azul) (Isla Chañaral 1996, Playa de Santo Domingo, San Antonio, 16 March 1997) and South Africa, but it is unclear whether these birds were vagrants. As new colonies continue to be discovered, rough estimates of the world population are around 350,000-600,000 animals.[3]

New Zealand[edit]

Overall, little penguin populations in New Zealand have been decreasing. Some colonies have gone extinct and others continue to be at risk.[3] Some new colonies have been established in urban areas.[2] The species is not considered endangered in New Zealand, with the exception of the white-flippered subspecies found only on Banks Peninsula and nearby Motunau Island. Since the 1960s, the mainland population has declined by 60-70%; though there has been a small increase on Motunau Island.

Australia[edit]

Australian Little penguin colonies primarily exist on offshore islands where they are safe from feral terrestrial predators and human disturbances are rare. Colonies are found from Port Stephens in northern New South Wales around the southern coast to Fremantle, Western Australia.

New South Wales[edit]

An endangered population of Little Penguins exists at Manly, North Sydney Harbor. The population is protected under the NSW Threatened Species Conservation Act 1995 and has been managed in accordance with a Recovery Plan since the year 2000. The population once numbered in the hundreds, but has decreased to around 60 pairs of birds. The decline is believed to be mainly due to loss of suitable habitat, attacks by foxes and dogs and disturbance at nesting sites.[11]

The largest colony in New South Wales is on Montague Island. Up to 8000 breeding pairs are known to nest there each year.[12]

South Australia[edit]

In South Australia, Little penguin colony declines have been identified across the state. In some cases, colonies have declined to extinction (including the Neptune Islands, West Island, Wright Island, Pullen Island and several colonies on western Kangaroo Island), while others have declined from thousands of animals to few (Granite Island and Kingscote). A report released in 2011 presented evidence supporting the listing of the statewide population or the more closely monitored sub-population from St. Vincent's Gulf as Vulnerable under South Australia's National Parks & Wildlife Act 1974.[13] As of 2014, the Little penguin is not listed as a species of conservation concern,[14] despite ongoing declines at many colonies.

Tasmania[edit]

Tasmanian Little penguin population estimates range from 110,000–190,000 breeding pairs of which less than 5% are found on mainland Tasmania. Ever-increasing human pressure is predicted to result in the extinction of colonies on mainland Tasmania.[15]

Western Australia[edit]

The largest colony of Little penguins in Western Australia is located on Penguin Island. Approximately 1000 pairs nest there during the winter.[16]

Threats[edit]

Predation[edit]

Threats to little penguin populations include predation (both adult and nest predation) by a variety of terrestrial animals including cats, dogs, rats, foxes, large reptiles, ferrets and stoats.[2][3][17] Due to their diminutive size and the introduction of new predators, some colonies have been reduced in size by as much as 98% in just a few years, such as the small colony on Middle Island, near Warrnambool, Victoria, which was reduced from approximately 600 penguins in 2001 to less than 10 in 2005. Because of this threat of colony collapse, conservationists pioneered an experimental technique using Maremma Sheepdogs to protect the colony and fend off would-be predators.[18] Uncontrolled dogs or feral cats can have sudden and severe impacts on penguin colonies (more than the penguin's natural predators) and may kill many individuals.

Prey availability[edit]

Variation in prey abundance and distribution from year to year causes young birds to be washed up dead from starvation or in weak condition.[15]

Entanglement[edit]

Some Little penguins are drowned when amateur fisherman set gill nets near penguin colonies. Discarded fishing line can also present an entanglement risk and contact can result in physical injury, reduced mobility or drowning.[15]

Oil spills[edit]

Oil spills can be lethal for penguins and other sea birds. Oil is toxic when ingested and penguins' buoyancy and the insulative quality of their plumage is damaged by contact with oil.[15] Little penguin populations have been significantly impacted during two major oil spills at sea: the Iron Baron oil spill off Tasmania's north coast in 1995 and the grounding of the Rena off New Zealand in 2011.

Plastic pollution[edit]

Plastics are swallowed by Little penguins, who mistake them for prey items. They present a choking hazard and also occupying space in the animal's stomach. Indigestible material in a penguin's stomach can contribute to malnutrition or starvation. Other larger plastic items, such as bottle packaging rings can become entangled around penguins' necks impacting their mobility.[15]

Human development[edit]

The impacts of human habitation in proximity to Little penguin colonies include collisions with vehicles, direct harassment, burning and clearing of vegetation and housing development.[15]

Behaviour[edit]

Little penguins are diurnal and like many penguin species, spend the largest part of their day swimming and foraging at sea. During the breeding and chick rearing seasons, little penguins will leave their nest at sunrise, forage for food throughout the day and return to their nests just after dusk. Little penguins preen their feathers to keep them waterproof. They do this by rubbing a tiny drop of oil onto every feather from a special gland above the tail.

Diet[edit]

These birds feed by hunting small clupeoid fishes (including sardines and anchovies), cephalopods and crustaceans, for which they travel and dive quite extensively.[19][20] In New Zealand, important prey items include arrow squid, slender sprat, Graham's gudgeon, red cod and ahuru.[21] They are generally inshore feeders.[22] The use of data loggers has provided information of the diving behaviour of little penguins. 50% of their dives go no deeper than 2 m and the mean diving time is 21 seconds.[23] Yet, they are able to dive as deep as 20 m and remained submerged as long as 60 seconds.[24] Little penguins play an important role in the ecosystem as not only a predator to parasites but also a host. Recent studies have shown a new species of feather mite that feeds on the preening oil on the feathers of the penguin.[25]

Reproduction[edit]

Chick in nest burrow
Little penguin (Eudyptula minor) family exiting burrow at night, Bruny Island

Little penguins mature at different ages. The female matures at 2 years old. The male, however, matures at 3 years old. Little penguins only remain faithful to their partner in breeding seasons and whilst hatching eggs. At other times of the year they do tend to swap burrows. They exhibit site fidelity to their nesting colonies and nesting sites over successive years.

Little penguins can breed as isolated pairs, in colonies, or semi-colonially.[21] Nests are situated close to the sea in burrows excavated by the birds or other species, or in caves, rock crevices, under logs or in or under a variety of man-made structures including nest boxes, pipes, stacks of wood or timber, and buildings. They are monogamous within a breeding season, and share incubation and chick rearing duties. They are the only species of penguin capable of producing more than one clutch of eggs per breeding season, but few populations do so. The one or two white or lightly mottled brown eggs are laid from July to mid-November, and with rarer second (or even third) clutches beginning as late as December. Incubation takes up to 36 days. Chicks are brooded for 18–38 days, and fledge after 7–8 weeks.[21]

Little penguins typically return to their colonies to feed their chicks at dusk. The birds will tend to come ashore in small groups to provide some defence against predators which might pick off individuals one by one. In Australia, the strongest colonies are usually on cat-free and fox-free islands. However, the population on Granite Island (which is a fox, cat and dog-free island) has been severely depleted, from around 2000 penguins in 2001 down to 146 in 2009.

Relationship with humans[edit]

Feeding time at Melbourne Zoo

Little penguins have long been a curiosity to humans, and to children in particular. Captive animals are often exhibited in zoos. Historically, the animals have also been used as bait to catch Southern rock lobster, captured for amusement and eaten by ship-wrecked sailors and castaways to avoid starvation.[26][27] They have also been the victims of malicious attacks by humans and incidental bycatch by fishermen using nets.[28] The sites of many breeding colonies have developed into tourist destinations which provide an economic boost for coastal and island communities in Australia and New Zealand. These locations also often provide facilities and volunteer staff to support population surveys, habitat improvement works and Little penguin research programs.

Nocturnal Tours[edit]

South of Perth, Western Australia, visitors to Penguin Island are able to view penguins in a natural environment. Less than one hour from the centre of the city, it is possible to see little penguins in all months, including visiting sensitive areas where they remain on land for extended periods for the purposes of moulting.

At Phillip Island, Victoria, a viewing area has been established at the Phillip Island Nature Park to allow visitors to view the nightly "penguin parade". Lights and concrete stands have been erected to allow visitors to see but not photograph the birds interacting in their colony.[29]

In Otago, New Zealand town of Oamaru, where visitors may view the birds returning to their colony at dusk.[30] In Oamaru it is not uncommon for penguins to nest within the cellars and foundations of local shorefront properties, especially in the old historic precinct of the town. More recently, little penguin viewing facilities have been established at Pilots Beach, Otago Peninsula and Dunedin in New Zealand. Here visitors are guided by volunteer wardens to watch penguins returning to their burrows at dusk.[31]

Visitors to Kangaroo Island, South Australia, have nightly opportunities to observe penguins at the Kangaroo Island Marine Centre in Kingscote and at the Penneshaw Penguin Centre.[32] Granite Island at Victor Harbor, South Australia continues to offer guided tours at dusk, despite its colony dropping from thousands in the 1990s to dozens in 2014.[33] There is also a Penguin Centre located on the island where the penguins can be viewed in captivity.[34]

In Bicheno, Tasmania, evening penguin viewing tours are offered by a local tour operator at a rookery on private land.[35]

Habitat restoration[edit]

Several efforts have been made to improve breeding sites on Kangaroo Island, including augmenting habitat with artificial burrows and revegetation works. The Knox School's habitat restoration efforts were filmed and broadcast in 2008 by Totally Wild.

Zoological exhibits[edit]

Little penguins at Sea World, Gold Coast, Queensland, Australia (photo 2005)

Exhibits currently exist at the Adelaide Zoo, Melbourne Zoo, the National Zoo & Aquarium in Canberra, Perth Zoo and the Taronga Zoo in Sydney.[36][37][38][39][40]

A colony of little penguins is also exhibited at Sea World, on the Gold Coast, Queensland, Australia. In early March, 2007, 25 of the 37 penguins died from an unknown toxin following a change of gravel in their enclosure.[41][42][43] It is still not known what caused the deaths of the little penguins, and it was decided not to return the 12 surviving penguins to the same enclosure in which the penguins became ill.[44] A new enclosure for the little penguin colony was opened at Sea World in 2008.[citation needed]

Little penguin at night at the
St Kilda breakwater

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Predator management[edit]

Little penguins in the wild are sometimes preyed upon by New Zealand fur seals. A study conducted by researchers from the South Australian Research and Development Institute found that roughly 40 percent of seal droppings in South Australia's Granite Island area contained little penguin remains.[45][46]

They are also preyed upon by White-bellied sea eagles. These large birds-of-prey are endangered in South Australia and not considered a threat to colony viability.

On land, Little penguins are vulnerable to attack from domestic and feral dogs and cats. Attacks on Kangaroo Island and in Tasmania have resulted in significant impacts to several populations.

Little penguins on Middle Island in Warrnambool, Victoria were subject to heavy predation by foxes, which were able to reach the island at low tide by a tidal sand bridge. The deployment of Maremma sheepdogs to protect the penguin colony has deterred the foxes and enabled the penguin population to rebound.[47] This is in addition to the support from groups of volunteers who work to protect the penguins from attack at night.

In Sydney, snipers have been deployed to protect a colony of little penguins.[48] This effort is in addition to support from local volunteers who work to protect the penguins from attack at night.

Mascots & logos[edit]

Linus Torvalds, the original creator of Linux (a popular operating system kernel), was once pecked by a little penguin while on holiday in Australia. Reportedly, this encounter encouraged Torvalds to select Tux as the official Linux mascot.[49]

Penny the Little Penguin was the mascot for the 2007 FINA World Swimming Championships held in Melbourne, Victoria.[50][51]

See also[edit]

References[edit]

  1. ^ BirdLife International (2012). "Eudyptula minor". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013. 
  2. ^ a b c Grabski, Valerie (2009). "Little Penguin - Penguin Project". Penguin Sentinels/University of Washington. Retrieved 2011-11-25. 
  3. ^ a b c d Dann, Peter. "Penguins: Little (Blue) Penguins - Eudyptula minor". International Penguin Conservation Work Group. Retrieved 2011-11-25. 
  4. ^ "Eudyptula minor variabilis; holotype". Collections Online. Museum of New Zealand Te Papa Tongarewa. Retrieved 17 July 2010. 
  5. ^ "Eudyptula minor chathamensis; holotype". Collections Online. Museum of New Zealand Te Papa Tongarewa. Retrieved 17 July 2010. 
  6. ^ Banks, Jonathan C.; Mitchell, Anthony D.; Waas, Joseph R. & Paterson, Adrian M. (2002): An unexpected pattern of molecular divergence within the blue penguin (Eudyptula minor) complex. Notornis 49(1): 29–38. PDF fulltext
  7. ^ Baker AJ, Pereira SL, Haddrath OP, Edge KA (2006). "Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling". Proc Biol Sci. 273 (1582): 11–17. doi:10.1098/rspb.2005.3260. PMC 1560011. PMID 16519228. 
  8. ^ Williams (The Penguins) p. 230
  9. ^ Dann, Peter (2005). "Longevity in Little Penguins" (PDF). Marine Ornithology (33): 71–72. Retrieved 17 September 2012. 
  10. ^ "Birds of world significance: Babel Island Group, Tasmania". Atlas of Australian Birds. Birds Australia. Retrieved 29 November 2011. 
  11. ^ "Little Penguin population in Sydney's North Harbor". NSW Government - Environment & Heritage. Retrieved 2014-07-27. 
  12. ^ "About Montague". Montague Island NSW. Retrieved 2014-07-27. 
  13. ^ Wiebkin, A. S. (2011) Conservation management priorities for little penguin populations in Gulf St Vincent. Report to Adelaide and Mount Lofty Ranges Natural Resources Management Board. South Australian Research and Development Institute (Aquatic Sciences), Adelaide. SARDI Publication No. F2011/000188-1. SARDI Research Report Series No.588. 97pp.
  14. ^ "Eudyptula minor". Atlas of Living Australia. Retrieved 2014-07-26. 
  15. ^ a b c d e f "Eudyptula minor - Little Penguin". Parks & Wildlife Service, Tasmania. Retrieved 2014-07-27. 
  16. ^ Visit beautiful Penguin Island http://www.penguinisland.com.au/visitor-information.html# |url= missing title (help). Retrieved 2014-07-27. 
  17. ^ "BBC - Science & Nature -Sea Life - Fact Files: Little/Fairy penguin". bbc. July 2005. Retrieved 2011-11-25. 
  18. ^ Vieru, Tudor (2009-01-07). "Sheepdogs Guard Endangered Fairy Penguin Colony". Softpedia. Retrieved 2011-11-25. 
  19. ^ Flemming, S.A., Lalas, C., and van Heezik, Y. (2013) "Little penguin (Eudyptula minor) diet at three breeding colonies in New Zealand". New Zealand Journal of Ecology 37: 199–205 Accessed 30 January 2014.
  20. ^ "Little Penguin Factsheet" Auckland Council, New Zealand (2014-02-28). Accessed 2014-07-26.
  21. ^ a b c Flemming, S.A. (2013) "[1]". In Miskelly, C.M. (ed.) New Zealand Birds Online
  22. ^ Numata, M; Davis, L & Renner, M (2000) "[Prolonged foraging trips and egg desertion in little penguins (Eudyptula minor)]". New Zealand Journal of Zoology 27: 291-298
  23. ^ Bethge, P; Nicol, S; Culik, BM & RP Wilson (1997) "Diving behaviour and energetics in breeding little penguins (Eudyptula minor)". Journal of Zoology 242: 483-502
  24. ^ Ropert-Coudert Y, Chiaradia A, Kato A (2006) "An exceptionally deep dive by a Little Penguin Eudyptula minor". Marine Ornithology 34: 71-74
  25. ^ Ashley Chung. "Eudyptula minor Little Penguin". Animal Diversity Web. Retrieved 2013-07-09. 
  26. ^ Hay, Alexander (1949-09-24). "Days of Misery on Barren Isle". The Mail (Adelaide, South Australia). Retrieved 2014-07-28. 
  27. ^ "S.A. Pair Marooned on Barren Island". The Advertiser (Adelaide, South Australia). 1949-09-19. Retrieved 2014-07-28. 
  28. ^ Pim, Mr. (1951-03-02). "Passing By". News (Adelaide, South Australia). Retrieved 2014-07-28. 
  29. ^ Tourism Victoria. "Phillip Island Penguin Parade". Visit Victoria. Retrieved 21 July 2011. 
  30. ^ "Oamaru Blue Penguin Colony". Penguins.co.nz. Retrieved 2012-06-12. 
  31. ^ "Blue Penguins Pukekura". Bluepenguins.co.nz. Retrieved 2012-06-12. 
  32. ^ "Penneshaw Penguin Centre". Tourkangarooisland.com.au. Retrieved 2012-06-12. 
  33. ^ "Granite Island Recreation & Nature Park : Penguin Tours South Australia". Graniteisland.com.au. Retrieved 2012-06-12. 
  34. ^ "Granite Island Penguin Centre : Looking after the Little Penguins of South Australia". Graniteisland.com.au. Retrieved 2012-06-12. 
  35. ^ Tourism Tasmania > Bicheno Penguin Tours Accessed 16 September 2013.
  36. ^ "Little Blue Penguin". Zoos South Australia. Retrieved 12 March 2014. 
  37. ^ "Little Penguin". Zoos Victoria. Retrieved 12 March 2014. 
  38. ^ "AdventureTrail". National Zoo & Aquarium. Retrieved 12 March 2014. 
  39. ^ "Little Penguin". Perth Zoo. Retrieved 12 March 2014. 
  40. ^ "Australian Little Penguin". Taronga Conservation Society Australia. Retrieved 12 March 2014. 
  41. ^ "Mystery penguin deaths at Sea World". Australian Broadcasting Corporation. Retrieved 15 August 2012. 
  42. ^ Authorities find unknown toxin in Sea World Penguins[dead link]
  43. ^ Sea World probes mysterious deaths[dead link]
  44. ^ Penguin deaths remain a mystery[dead link]
  45. ^ Penguins —Environment, South Australian Government[dead link]
  46. ^ Littlely, Bryan (2007-10-10). "Fur seals threat to Granite Island penguins". The Advertiser. p. 23. 
  47. ^ "Dogs come to fairy penguins' rescue". Special Broadcasting Service. 5 January 2009. Retrieved 2009-01-07. 
  48. ^ "Penguin murders prompt sniper aid". BBC. 16 July 2009. Retrieved 2009-07-16. 
  49. ^ ""Tux" the Aussie Penguin". Linux Australia. Archived from the original on 2006-05-07. Retrieved 2006-06-25. 
  50. ^ "FINA". Melbourne, 2007. Retrieved 2012-06-12. 
  51. ^ Protecting our Little Penguins (Victorian Government website)[dead link]

Further reading[edit]

  • Williams, Tony D. (1995). The Penguins. Oxford, England: Oxford University Press. ISBN 0-19-854667-X. 

External links[edit]