Overview

Brief Summary

Biology

A gregarious species, the northern rockhopper penguin breeds in large colonies that may comprise over a hundred thousand nests. Breeding pairs are monogamous, and usually return to the same nest every year (2). Egg-laying commences around August (3), with the female usually producing a clutch of two eggs of unequal size (2). Usually only the chick from the larger egg survives to maturity. Incubation takes around 33 days, with both parent birds taking it in turns to sit on the eggs for extended periods of a time, whilst the other forages for food. Incubation is aided by a bare patch of skin on the lower abdomen (known as a 'brood pouch') that allows greater heat transfer to the egg. Once hatched, the male will remain to brood the chick for the first 25 days, whilst the female regularly brings food back to the nest. After this time, the chick is able to leave the nest, and will congregate with other chicks in small groups known as 'crèches' whilst the parent birds forage (2). In order to maintain its waterproof coat, the northern rockhopper penguin engages in frequent grooming, which helps to flatten the feathers and to spread a waxy substance that is secreted just below the tail. Grooming is also an important social bond between pairs. After breeding the northern rockhopper penguin forages extensively in order to build up fat reserves in preparation for its annual moult. It takes around 25 days for the penguin's coat to be fully replaced, at which point it leaves the land and spends the winter months foraging at sea, before returning to shore to breed in the following spring (2). The diet of the northern rockhopper penguin is composed of a variety of oceanic species, such as crustaceans, squid, octopus and fish (4). Groups may often feed together and dives may be to depths of up to 100 metres (2).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Wildscreen

Source: ARKive

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Description

Previously classed as a single species, the rockhopper penguin has now been split into a northern (Eudyptes moseleyi) and southern species (Eudyptes chrysocome) (3). Although both species are similar in appearance, the distinctive yellowish plumes extending from the yellow line above the eye are significantly longer and denser in the northern rockhopper penguin (2) (3). The body is small but robust, with slate-grey upperparts and white underparts, the bill is short and reddish-brown and the eyes are red. Juveniles can be identified by the lack of adult yellow markings (2).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Wildscreen

Source: ARKive

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Distribution

Range Description

Eudyptes moseleyi is found in the South Atlantic and Indian Ocean. It has a restricted breeding range, occurring on just seven islands with a total land area of 250 km2. The majority are found on Gough Island and islands in the Tristan da Cunha group (St Helena to UK), with 83,000 pairs on Middle Island (2009), 64,700 pairs on Gough (2006), 25,000 pairs on Nightingale (2009), 54,000 pairs on Inaccessible (2009) and 6,700 pairs on Tristan (2009) (BirdLife International 2010, BirdLife International 2012). The rest of the population is found in the India Ocean with 24,890 pairs on Amsterdam Island and 9,023 pairs on St Paul Island (French Southern Territories). Early records indicate that millions of penguins used to occur on both Tristan da Cunha and Gough Island. Approximately 2 million pairs (98%) were lost from Gough Island between 1955 and 2006 and Tristan da Cunha is thought to have held hundreds of thousands of pairs in the 1870s, which were reduced to around 5,000 pairs by 1955 (Cuthbert et al. 2009). The breeding colonies on Amsterdam and St Paul Islands have reduced in size by 40% (Guinard et al. 1998). Population modelling, based on those breeding sites that have been accurately surveyed, indicates that over the past 37 years (= 3 generations) the number of Northern Rockhopper Penguins has declined by 57% (Birdlife International 2010).

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Range

Tristan da Cunha, Gough, St. Paul and Amsterdam islands.
  • Clements, J. F., T. S. Schulenberg, M. J. Iliff, D. Roberson, T. A. Fredericks, B. L. Sullivan, and C. L. Wood. 2014. The eBird/Clements checklist of birds of the world: Version 6.9. Downloaded from http://www.birds.cornell.edu/clementschecklist/download/

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Range

The northern rockhopper penguin breeds on a number of Southern Ocean islands, with the largest populations found on the islands of Tristan da Cunha and Gough, and additional, smaller populations on the islands of Amsterdam and St Paul (4).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Wildscreen

Source: ARKive

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Ecology

Habitat

Habitat and Ecology

Habitat and Ecology
Adults arrive at the breeding colonies in late July and August. Nests are located in a variety of habitats ranging from open boulder-strewn beaches on Gough Island to among stands of tussock grass (mainly Spartina arundinacea) on Nightingale and Inaccessible islands (Cuthbert 2012). They feed mainly on krill. Other prey items include other crustaceans, squid, octopus and fish (Williams 1995).


Systems
  • Marine
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Nesting occurs on cliffs and rocky gullies, and chosen sites are usually situated near to freshwater, either natural springs or puddles (2).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Wildscreen

Source: ARKive

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Conservation

Conservation Status

IUCN Red List Assessment


Red List Category
EN
Endangered

Red List Criteria
A2acde+3cde+4acde

Version
3.1

Year Assessed
2012

Assessor/s
BirdLife International

Reviewer/s
Symes, A. & Butchart, S.

Contributor/s
Cuthbert, R. & Hilton, G.

Justification
This species has been classified as Endangered owing to very rapid population decreases over the last three generations (30 years) throughout its range. Precise reasons for the declines are poorly known, but changes in sea temperature, competition and incidental capture in fisheries and introduced predators are all likely to be implicated.


History
  • Endangered (EN)
  • Endangered (EN)
  • Not Recognized (NR)
  • Not Recognized (NR)
  • Not Recognized (NR)
  • Not Recognized (NR)
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5