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Monday, December 1, 2008

Fiordland crested penguin (Eudyptes pachyrhynchus)



Facts
Also known as: thick-billed penguin
Kingdom Animalia
Phylum Chordata
Class Aves
Order Sphenisciformes
Family Spheniscidae
Genus Eudyptes (1)
Size Length: up to 55 cm (2)
Height: 40 cm (2)
Weight 4 kg (2)
Status

Classified as Vulnerable (VU) on the IUCN Red List 2007 (1).

Description

One of the smaller members of the penguin family, the Fiordland crested penguin has a black head, throat and back, a white front and underside, a thick stubby orange bill and pink feet. The most distinguishing features are the yellow sulphur-coloured crests above the eyes that extend from the bill to just behind the head. Both sexes are similar, whereas young birds have paler cheeks and shorter crests (2) (4).

Like other members of the genus Eudyptes the Fiordland crested penguin has a black throat but can be distinguished from the similar Rockhopper, Macaroni and Royal penguins by the shape, extent and colour of the eye crests (4). The two species that can be confused with the Fiordland crested are the erect-crested penguin and the Snares Island penguin. The former has eye crests that stand proud of the top of the head and no part which extends to below the eye itself. The latter is a slightly larger bird with a thicker bill (4).

Range

A migratory species, found in Antarctic waters and around the southern circumpolar islands, the Fiordland penguin breeds on the coast of southwest New Zealand, Stewart Island and Solander Island (5).

Habitat

Outside the breeding season, Fiordland crested penguins are birds of the open ocean. When ashore to breed they prefer secluded coastlines and chose nesting sites that are amongst rocks or have tree cover (3).

Biology

After spending much of the year alone in the open ocean, males arrive at the chosen breeding site ahead of the females during late June or July. Two weeks later the females arrive and mating takes place. The birds are monogamous and prefer their nest sites to be hidden from one another. Two pale-green eggs are laid in a cavity between tree roots, stones or small burrows in the coastal forest, and incubation takes from four to six weeks. The birds do not attempt to collect nest materials. Although it is usual for just one egg to hatch successfully, occasionally both chicks emerge. However, the parents rarely catch enough food for two offspring and the smaller chick usually dies (3).

While the chick is still defenceless, one parent (usually the male), will guard it whilst the other finds food. Fiordland crested penguins feed inshore and catch crustaceans, squid and small fish which they regurgitate for the chick. Once the young is large enough to be safe from most native predators, both parents take on the role of fishing to provide their offspring with food. Chicks often wander about the nest site or gather in loose-knit crèches. After about 10 or 11 weeks, the chick moults and leaves the nest site, finally adopting the solitary pelagic lifestyle of the adult birds. It will return to breed at the age of five years (2) (3).

Threats

The Fiordland crested penguin has declined in numbers drastically during the last twenty years. In the 1980s, the global population was estimated to number 10,000 breeding pairs. Today, the number is thought to be 2,500 to 3,000 pairs. The principal cause is believed to be from introduced animals such as cats and stoats (5), although where the birds' breeding sites are close to public beaches, pet dogs are thought to be largely responsible for disturbing adult birds and catching chicks. With the increase in human leisure activities, this pressure is bound to intensify (2). There is also a problem with the endemic weka, Gallirallus australis, which preys on eggs and chicks and is thought to contribute to over a third of egg loses in some breeding areas, especially Solander Island (5).

At sea, penguins are in constant competition for food with fishing vessels and sometimes find themselves caught in fishing nets. Perhaps the biggest threat, however, is through marine pollution, particularly oil spillage and the illegal but common practice of discharging oil tanker ballast water off-shore (5). As yet, little is known about the possible effects of global warming on penguin populations (5).

Conservation

Recent surveys of a number of the Fiordland crested penguin's breeding areas have suggested that more research into predator-related threats need to be examined. One idea is to eradicate the weka – the principal local predator – from Solander Island to reduce the losses of eggs and chicks (5).

References

1. IUCN Red List (April, 2007)
http://www.iucnredlist.org
2. International Penguin Conservation (April, 2004)
http://www.penguins.cl/fiordland-penguins.htm
3. Animal Diversity Web, University of Michigan Museum of Zoology (April, 2004)
http://animaldiversity.ummz.umich.edu/site/accounts/information/Eudyptes_pachyrhynchus.html
4. Sparks, J. and Soper, T. (1968) Penguins. David and Charles, Newton Abbott.
5. Birdlife International (2003) Birdlife's on-line World Bird Database: the site for bird conservation. Version 2.0. Cambridge, UK: Birdlife International (April, 2004)
http://www.birdlife.org/datazone/species/index.html?action=SpcHTMDetails.asp&sid=3854&m=0

Fact sheet from Archive@
http://www.arkive.org/fiordland-crested-penguin/eudyptes-pachyrhynchus/info.html
Picture from: http://www.md.ucl.ac.be/peca/test/Fiordland%20Crested%20Penguin.jpg

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