Little penguin

The little penguin (Eudyptula minor) is a species of penguin from New Zealand. They are commonly known as little blue penguins or blue penguins owing to their slate-blue plumage. They are also known by their Māori name kororā.

Little penguin
Blue Penguin Kapiti.jpg
Little penguin (Eudyptula minor), moving up from the shore at night towards its burrow on Kapiti Island, New Zealand.
Scientific classification edit
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Sphenisciformes
Family: Spheniscidae
Genus: Eudyptula
Species:
E. minor
Binomial name
Eudyptula minor
(J.R.Forster, 1781)
Map-of-distribution-of-Eudyptula-penguins-Blue-and-red-colours-indicate.png
The range of Eudyptula minor is in blue.[2]

The Australian little penguin (Eudyptula novaehollandiae) from Australia and the Otago region of New Zealand is considered a separate species by a 2016 study[3] and a 2019 study.[4]

TaxonomyEdit

 
A white-flippered penguin in the South Island.

The little penguin was first described by German naturalist Johann Reinhold Forster in 1781. Several subspecies are known, but a precise classification of these is still a matter of dispute. The holotypes of the subspecies E. m. variabilis[5] and Eudyptula minor chathamensis[6] are in the collection of the Museum of New Zealand Te Papa Tongarewa. The white-flippered penguin (E. m. albosignata or E. m. minor morpha albosignata) is currently considered by most taxonomists to be a colour morph or subspecies of Eudyptula minor. In 2008, Shirihai treated the little penguin and white-flippered penguin as allospecies.[7] However, as of 2012, the IUCN and BirdLife International consider the white-flippered penguin to be a subspecies or morph of the little penguin.

Little penguins from New Zealand and Australia were once considered to be the same species, called Eudyptula minor. Analysis of mtDNA in 2002 revealed two clades in Eudyptula: one containing little penguins of New Zealand's North Island, Cook Strait and Chatham Island, as well as the white-flippered penguin, and a second containing little penguins of Australia and the Otago region of New Zealand.[8] Preliminary analysis of braying calls and cluster analysis of morphometrics partially supported these results.[8] A 2016 study described the Australian little penguin as a new and separate species, Eudyptula novaehollandiae. E. minor is endemic to New Zealand, while E. novaehollandiae is found in Australia and Otago.[3] A 2019 study supported the recognition of E. minor and E. novaehollandiae as separate species.[4]

DescriptionEdit

Like those of all penguins, the wings of Eudyptula species have developed into flippers used for swimming.

Eudyptula species typically grow to between 30 and 33 cm (12 and 13 in) tall and on average weigh 1.5 kg (3.3 lb). The head and upper parts are blue in colour, with slate-grey ear coverts fading to white underneath, from the chin to the belly. Their flippers are blue in colour. 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.[9]

Like most seabirds, the Eudyptula species have a long lifespan. The average for the species is 6.5 years, but flipper ringing experiments show that in very exceptional cases they may live up to 25 years in captivity.[10]

Eudyptula minor does not have the distinct bright blue feathers that distinguish Eudyptula novaehollandiae. In addition, the vocalisation patterns of the New Zealand lineage located on Tiritiri Matangi Island vary from the Australian lineage located in Oamaru. Females are known to prefer the local call of the New Zealand lingeage.

There are also behavioural differences that help differentiate these penguins. Those of the Australian lineage will swim together in a large group after dusk and walk along the shore to reach their nesting sites. This may be an effective predator avoidance strategy by traveling in a large group simultaneously. This has not been seen by those of the New Zealand lineage. Eudyptula minor only recently encountered terrestrial vertebrate predators, while Eudyptula novaehollandiae would have had to deal with carnivorous marsupials.

Also, Eudyptula novaehollandiae located in Australia will double brood. Birds will double brood by laying another clutch of eggs in hopes to increase their reproductive success. They complete this after the first clutch has successfully fledged. They may also do this due to the increasing sea surface temperatures and changing sources of food that are available. This behaviour has never been observed by those in New Zealand.[11]

Distribution and habitatEdit

New ZealandEdit

Eudyptula minor breeds along most of the coastline of New Zealand, including the Chatham Islands. However, Eudyptula minor does not occur in Otago, which is located on the east coast of New Zealand's South Island. The Australian species Eudyptula novaehollandiae occurs in Otago.[12] E. novaehollandiae was originally endemic to Australia. Using ancient-DNA analysis and radiocarbon dating using historical, pre-human, as well as archaeological Eudyptula remains, the arrival of the Australian species in New Zealand was determined to have occurred roughly between AD 1500 and 1900. When the E. minor population declined in New Zealand, it left a genetic opening for E. novaehollandiae. The decrease of E. minor was most likely due to anthropogenic effects, such as being hunted by humans as well as introduced predators,[13] including dogs brought from overseas.

It has been determined that the population of Eudyptula novaehollandiae in Otago arrived even more recently than previously estimated due to mulitlocus coalescent analyses.[14]

Overall, little penguin populations in New Zealand have been decreasing. Some colonies have become extinct, and others continue to be at risk.[15] Some new colonies have been established in urban areas.[16] 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 a small increase has occurred on Motunau Island. A colony exists in Wellington Harbor on Matiu / Somes Island.

Outside of AustralasiaEdit

Eudyptula species have also been reported from Chile, where they are known as pingüino pequeño or pingüino azul. Sightings include Isla Chañaral 1996 and Playa de Santo Domingo, San Antonio, 16 March 1997. Eudyptula species have also been reported from South Africa, It is unclear whether these birds were vagrants.

ThreatsEdit

 
Traffic sign warning of little penguins crossing on the West Coast of New Zealand

Protestors have opposed the development of a marina at Kennedy Point, Waiheke Island in New Zealand for the risk it poses to little penguins and their habitat.[17] Protesters claimed that they exhausted all legal means to oppose the project and have had to resort to occupation and non-violent resistance. Several arrests have been made for trespassing.[18]

ConservationEdit

Eudyptula species are classified as "at risk - declining" under Wildlife Act 1953.[19]

Zoological exhibitsEdit

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

Zoological exhibits featuring purpose-built enclosures for Eudyptula species can be seen in Australia at the Adelaide Zoo, Melbourne Zoo, the National Zoo & Aquarium in Canberra, Perth Zoo, Caversham Wildlife Park (Perth), Ballarat Wildlife Park, Sea Life Sydney Aquarium,[20] and the Taronga Zoo in Sydney.[21][22][23][24][25][26][27] Enclosures include nesting boxes or similar structures for the animals to retire into, a reconstruction of a pool and in some cases, a transparent aquarium wall to allow patrons to view the animals underwater while they swim.

Eudyptula penguin exhibit exists 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.[28][29][30] It is still not known what caused the deaths of the penguins, and it was decided not to return the 12 surviving penguins to the same enclosure where the penguins became ill.[31] A new enclosure for the little penguin colony was opened at Sea World in 2008.[32]

In New Zealand, Eudyptula penguin exhibits exist at the Auckland Zoo, the Wellington Zoo, and the National Aquarium of New Zealand.[33] Since 2017, the National Aquarium of New Zealand, has featured a monthly "Penguin of the Month" board, declaring two of their resident animals the "Naughty" and "Nice" penguin for that month. Photos of the board have gone viral and gained the aquarium a large worldwide social media following.[34]

A colony of Eudyptula penguins exists at the New England Aquarium in Boston, Massachusetts. The penguins are one of three species on exhibit and are part of the Association of Zoos and Aquariums' Species Survival Plan for Eudyptula penguin.[35] Eudyptula penguins can also be seen at the Louisville Zoo[36] and the Bronx Zoo.[37]

See alsoEdit

  Animals portal

NotesEdit

  1. ^ This IUCN assessment treats Eudyptula minor and Eudyptula novaehollandiae as just one species.

ReferencesEdit

  1. ^ BirdLife International (2020). "Eudyptula minor". IUCN Red List of Threatened Species. 2020: e.T22697805A202126091. doi:10.2305/IUCN.UK.2020-3.RLTS.T22697805A202126091.en. Retrieved 13 November 2021.
  2. ^ "Fig 1. Map of distribution of Eudyptula penguins. Blue and red colours..." ResearchGate. Retrieved 15 May 2022.
  3. ^ a b Grosser, Stefanie; Rawlence, Nicolas J.; Anderson, Christian N. K.; Smith, Ian W. G.; Scofield, R. Paul; Waters, Jonathan M. (10 February 2016). "Invader or resident? Ancient-DNA reveals rapid species turnover in New Zealand little penguins". Proceedings of the Royal Society B: Biological Sciences. 283 (1824): 20152879. doi:10.1098/rspb.2015.2879. ISSN 0962-8452. PMC 4760177. PMID 26842575.
  4. ^ a b Cole, Theresa L; Ksepka, Daniel T; Mitchell, Kieren J; Tennyson, Alan J D; Thomas, Daniel B; Pan, Hailin; Zhang, Guojie; Rawlence, Nicolas J; Wood, Jamie R; Bover, Pere; Bouzat, Juan L (1 April 2019). "Mitogenomes Uncover Extinct Penguin Taxa and Reveal Island Formation as a Key Driver of Speciation". Molecular Biology and Evolution. 36 (4): 784–797. doi:10.1093/molbev/msz017. ISSN 0737-4038. PMID 30722030.
  5. ^ "Eudyptula minor variabilis; holotype". Collections Online. Museum of New Zealand Te Papa Tongarewa. Retrieved 17 July 2010.
  6. ^ "Eudyptula minor chathamensis; holotype". Collections Online. Museum of New Zealand Te Papa Tongarewa. Retrieved 17 July 2010.
  7. ^ Shirihai, Hadoram (2008). The Complete Guide to Antarctic Wildlife, 2d Edition. Princeton University Press.
  8. ^ a b 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
  9. ^ Williams, Tony D. (1995). The penguins : Spheniscidae. Rory P. Wilson, P. Dee Boersma, David L. Stokes, Jeff Davies, John Busby. Oxford: Oxford University Press. ISBN 0-19-854667-X. OCLC 30736089.
  10. ^ Dann, Peter (2005). "Longevity in Little Penguins" (PDF). Marine Ornithology (33): 71–72. Retrieved 17 September 2012.
  11. ^ Grosser, Stefanie; Burridge, Christopher P.; Peucker, Amanda J.; Waters, Jonathan M. (14 December 2015). "Coalescent Modelling Suggests Recent Secondary-Contact of Cryptic Penguin Species". PLOS ONE. 10 (12): e0144966. doi:10.1371/journal.pone.0144966. PMC 4682933. PMID 26675310.
  12. ^ "Australian and New Zealand Little Blue Penguins are Different Species". MessagetoEagle.com. 16 December 2015. Retrieved 12 May 2016.
  13. ^ Grosser, Stefanie. "NZ's southern little penguins are recent Aussie invaders: Otago research". University of Otago. University of Otago: Department of Zoology. Retrieved 11 May 2016.
  14. ^ Grosser, Stefanie; Burridge, Christopher P.; Peucker, Amanda J.; Waters, Jonathan M. (14 December 2015). "Coalescent Modelling Suggests Recent Secondary-Contact of Cryptic Penguin Species". PLOS ONE. 10 (12): e0144966. doi:10.1371/journal.pone.0144966. PMC 4682933. PMID 26675310.
  15. ^ Dann, Peter. "Penguins: Little (Blue or Fairy) Penguins - Eudyptula minor". International Penguin Conservation Work Group. Retrieved 25 November 2011.
  16. ^ Grabski, Valerie (2009). "Little Penguin - Penguin Project". Penguin Sentinels/University of Washington. Archived from the original on 16 December 2011. Retrieved 25 November 2011.
  17. ^ "Police arrest three at Waiheke Island marina protest". NZ Herald. Retrieved 17 June 2021.
  18. ^ "Arrests at Waiheke's Kennedy Point as fight to protect penguins escalates". Stuff. 17 June 2021. Retrieved 17 June 2021.
  19. ^ "Wildlife Act 1953 No 31 (as at 02 August 2019), Public Act Contents – New Zealand Legislation". legislation.govt.nz. Retrieved 28 May 2020.
  20. ^ Sea Life Sydney Aquarium
  21. ^ "Little Blue Penguin" (PDF). Zoos South Australia. Archived from the original (PDF) on 15 May 2013. Retrieved 12 March 2014.
  22. ^ "Little Penguin". Zoos Victoria. Retrieved 12 March 2014.
  23. ^ "AdventureTrail" (PDF). National Zoo & Aquarium. Archived from the original (PDF) on 12 March 2014. Retrieved 12 March 2014.
  24. ^ "Little Penguin". Perth Zoo. Archived from the original on 28 February 2014. Retrieved 12 March 2014.
  25. ^ "Australian Little Penguin". Taronga Conservation Society Australia. Archived from the original on 24 March 2014. Retrieved 12 March 2014.
  26. ^ "Little Penguins | SEA LIFE Sydney Aquarium". www.sydneyaquarium.com.au. Retrieved 23 April 2020.
  27. ^ "Little Penguins". Ballarat Wildlife Park. Retrieved 21 April 2020.
  28. ^ "Mystery penguin deaths at Sea World". Australian Broadcasting Corporation. Retrieved 15 August 2012.
  29. ^ Authorities find unknown toxin in Sea World Penguins Archived 13 February 2011 at the Wayback Machine
  30. ^ Sea World probes mysterious deaths Archived 13 February 2011 at the Wayback Machine
  31. ^ Penguin deaths remain a mystery Archived 21 March 2008 at the Wayback Machine
  32. ^ "Seaworld opens new haven for penguins". Brisbane Times. 8 March 2008. Retrieved 24 January 2019.
  33. ^ National Aquarium of New Zealand > New Zealand Land Animals - Little Penguin, Nationalaquarium.vo.nz, Accessed 27 December 2014
  34. ^ "Naughty Penguin of the Month is Giving Twitter Life to this Viral Thread". Bustle.com. Retrieved 27 December 2021.
  35. ^ New England Aquarium > Animals and Exhibits > Little Blue Penguin Archived 15 March 2015 at the Wayback Machine Accessed 2 March 2014
  36. ^ "Penguin Cove – Little Penguin Conservation Center". Louisville Zoo. 20 April 2016. Retrieved 21 April 2020.
  37. ^ "Little Penguins Make a Big Splash - Bronx Zoo". bronxzoo.com. Retrieved 21 April 2020.

Further readingEdit

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

External linksEdit