User:AEON31459/sandbox

Fiordland Penguin

Fiordland Penguin
Two Individuals resting on a shoreline
Conservation status
Near Threatened (IUCN 3.1)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Sphenisciformes
Family:	Spheniscidae
Genus:	Eudyptes
Species:	E. pachyrhynchus
Binomial name
Eudyptes pachyrhynchus G. R. Gray, 1845
Breeding range

The Fiordland Penguin, Fiordland crested penguin, or Tawaki/Pokotiwha (Eudyptes pachyrhynchus) is a crested penguin species endemic to the South Island of New Zealand. It is located along the coastlines of South-West and on Stewart Island/Rakiura. It is one of the four species of Penguin that breed in New Zealand, the others being the Snares penguin (Eudyptes robustus), the Yellow-eyed Penguin (Megadyptes antipodes), and the Little Penguin (Eudyptula minor). The is near threatened because of human disturbance at nest sites and introduced predators mainly by Stoats (Mustela erminea) and as a result the species has been on the decline since the 1950s.

Taxonomy

The first description of the species was in 1845 and comes from English zoologist George Robert Gray. The species was considered a subspecies related to the Erect-crested penguin and the Snares penguin. In 1953, this was disputed and changed because of the morphological differences between the 3 species.

Difference between a Fiordland Penguin (bottom) and an Erect-Crested Penguin (top)

As a member of the Eudyptes genus the name derives from Ancient Greek "ευδύπτης" meaning good diver. The species name also comes from the Ancient Greek word "παχυρύγχος" meaning thick beak. The Māori name for the species comes from Māori mythology named after the god of lightning and thunder, Tāwhaki.

Description

Adult in Fiordland

The Fiordland Penguin is a mid-sized penguin that is similar in appearance to other members of the genus Eudyptes, having long sulfur-crested eyebrows that extend to the back of the neck as well as red/brown eyes. It can be distinguished by other species of Eudyptes by having 3-6 white check stripes and little skin on the base of its bill. The head, neck and back are black while the front is white. An adult bird can reach up to 55cm (~22 inches) and weigh up to 4kg (~9 pounds).There is little sexual dimorphism with the males weighing slightly more on average than females, however they can be differentiated by bill length with those less than 24 millimeters (0.9 inches) being female while more than 24 millimeters are male.

The juveniles are smaller and have white eyebrows that do not extend out as much compared to an adult. The chicks are have gray/brown feathers instead of black feathers.

Distribution and Habitat

The breeding range only occurs on the south-western coast of the South Island and Stewart Islands. The distribution of the species might have been more widespread as fossil evidence shows that they breed on the northern South Island and could have reached as far north as Manawatu-Wanganui and the Wairarapa coastlines. When not breeding the range of the bird can go across the South of mainland New Zealand surrounding the New Zealand Subantarctic Islands and Macquarie Island. Vagrant populations have also been found all across New Zealand as well as reaching Tasmania in south-eastern Australia. The decrease in range is likely due to overhunting during the Archaic period of early Polynesian colonization. On land they live in temperate rainforests at the coasts of rocky shorelines where they breed.

Behavior

Feeding

The dietary preferences of the bird have not been studied in detail, but their diets vary from location. One study suggests that penguins that live in Fiordland mainly feed on a diet of Cephalopods mainly New Zealand arrow squid (Nototodarus sloanii) at 85%, followed by Crustaceans but mainly Krill (Nyctiphanes australis) at 13% and the rest being Fish at 2%. Another study shows that on Codfish Island the diet of the penguins there consisted of 85% fish, which was a mixture of juveniles of Red Cod, (Pseudophycis bachus) and Ahuru (Auchenoceros punctatus). The remainder of the diet consisted of cephalopods at 15% which were also New Zealand arrow squid. The penguin hunts on the continental shelf where all of its prey can be found and do not feed further offshore from the shelf.

Breeding penguins do not have the same diet and forage close to the coast within 2km or inshore within the fjords or off the coastline. Large bird colonies at up to 30 individuals patrol the inner coast around macroplankton which they consume instead.

Adult within crevice

Breeding

The penguins build their nests inside rock crevices or beneath objects such as boulders and tree roots. Unlike other Crested Penguins, there colonies are spacious and nests are separated from each other by several meters, meaning that the overall colony can stretch over a large part of coastline.

The breeding cycle starts midway through June where they come back from foraging and establish nests and a colony. The penguins are primarily monogamous and find their previous mates and also go back to previous nests that they might have inhabited previously. Reunited and monogamous pairs have a higher reproductive success rate than newly partnered pairs. If the pair fails to raise their offspring this might also cause them to separate and look for a new mate. Egg laying happens during August and pairs lay two eggs, the first being smaller than the latter. The egg-laying process takes around ten days with the two eggs separated by 3-6 days in age and when the final egg is laid the parents go on the prone position for incubation.

For the birds their is a high chance that only one egg hatches while the other is either lost or does not hatch, which is usually the first egg. It is more common for the first egg to die from other either starvation or exposure after expulsion.

The incubation period lasts for 31-36 days after the second egg is laid. They take turns incubating for the first 10 days then after this period the female goes to sea foraging while the male incubates and guards the offspring for up to 40 days, while the female returns every night to feed the chicks while the males fast. When the chicks are 3 weeks old they conglomerate with other chicks from other nests to form groups called Crèches, while the male departs to forage and the females guard their chicks. By late November the chicks have developed enough to become adults with both the parents and chicks leave to forage in preparation for molting.

Conservation

The Fiordland Penguin is most likely on the decline and it is listed on the IUCN Red list as Near Threatened. The number of penguins at monitored sites on the mainland has decreased by 30%, but it is unclear whether the decline of the population was legitimate or because of a migration to another location. The gradual shift to another location could potentially be because of sites becoming gradually deteriorating to become unsuitable. Offshore on predator-free islands the population has remained stable and overall the population is estimated to be around 5,000-10,000 individuals. The size and change in population is not clear because of the timidity of the species and the rough terrain of the region.

Threats

Fishing and net setting are allowed along the coastlines of the regions the penguin inhabit. Set netting poses the most serious risk to the penguin as it can easily get stuck between the holes and drown when hunting. Humans can also disturb the breeding process by interrupting the colonies through research and tourism .

Introduced predators also pose a potential risk in the region. Stoats have hunted endemic birds and their eggs in Fiordland since they were introduced to New Zealand and have also hunted these penguins before. There is no evidence that Rats have negatively impacted the penguin in anyway, while Dogs and Cats have hunted the bird near places of human habitation. Weka (Gallirallus australis) are also known to hunt their eggs, especially the smaller first laid eggs that the penguin is less likely to defend.