The Fiordland penguin (Eudyptes pachyrhynchus), also known as the Fiordland crested penguin (in Māori, tawaki or pokotiwha), is a crested penguin species endemic to New Zealand. It currently breeds along the south-western coasts of New Zealand's South Island as well as on Stewart Island/Rakiura and its outlying islands. Because it originally ranged beyond Fiordland, it is sometimes referred to as the New Zealand crested penguin.
Taxonomy
The Fiordland crested penguin was described in 1845 by English zoologist George Robert Gray, its specific epithet derived from the Ancient Greek pachy-/ "thick" and rhynchos/ "beak". It is one of the four to seven species in the genus Eudyptes, the generic name derived from the Ancient Greek eu/ευ "good" and dyptes/δύπτης "diver". long and weighing on average , with a weight range of . Female Fiordland penguins lay a clutch of two eggs where the first-laid egg is much smaller than the second egg, generally hatches later, and shows higher mortality, demonstrating a brood reduction system that is unique from other avian groups. The Fiordland crested penguin has a much higher breeding success than most other Eudyptes species except for the southern rockhopper penguin, even at sites with introduced and/or native predators.
Distribution and habitat
This penguin nests in colonies among tree roots and rocks in dense temperate coastal forest. It breeds along the shores in the West Coast of the South Island, south of about Bruce Bay and the Open Bay Islands, around Fiordland and Foveaux Strait, and on Stewart Island/Rakiura and its outlying islands. Their range drastically reduced by hunting in Polynesian times, and they are now only found in the least-populated part of New Zealand. The species was also present in Australia.
Behaviour
Diet
The main prey species reported are cephalopods (85%, mainly arrow squid, Nototodarus sloanii), followed by crustaceans (13%, primarily krill, Nyctiphanes australis) and fish (2%, mainly red cod and Blue grenadier (hoki)). However, the importance of cephalopods might be exaggerated. Prey taken seems to vary between Codfish Island and northern Fiordland.
Foraging ecology
Eudyptes pachyrhyncus are split into three groups based on their location in the fjord and where they hunt, dubbed the inner-fjord, mid-fjord and outer-fjord. Outer-fjord Eudyptes pachyrhynchus make long, deep dives with descent velocities reaching higher points than that of mid-fjord individuals who forage in the upper 20 meters of the water column. Domestic dogs prove to be great threats to the species with conservation campaigns encouraging dogs to be leashed at all times near habitats that Eudyptes pachyrhynchus occupies in order to aid the threatened population.
Reproductive and incubation habits
Reproductive and incubation habits of Fiordland crested penguins (Eudyptes pachyrhynchus) are not heavily researched however they provide an important view of the life cycles and reproductive success rates. Reproductive behaviours alter both feeding habits and intraspecies interactions due to courting behaviours After 4 months at sea breeding birds form small groups at the height of winter and breed annually from July to December Display behaviours involve attitudes where the flippers and crests are prominent as well as loud vocalizations. Each clutch features two eggs with the second being larger.
Eudyptes pachyrhynchus nest in small scattered groups across steep slopes covered by rainforests that protect them from extreme temperatures Fidelity to an egg site assists the reproductive success with no significant difference in nest fidelity between sexes. Though viewed as a monogamous group, failure to raise a chick can result in increased separation rates. despite a lack of association with aggressive behavior or nest crowding the first eggs continue to experience a greater rate of mortality than second eggs. Once the chick is ready to join a crèche at around 21 to 28 days old
When in captivity and exposed to concerts such as in Melbourne zoo time spent preening and interacting with their habitats was decreased in favour of spending time in the pool or using a nest. Post breeding period Eudyptes pachyrhynchus head south-west before splitting towards one of two trip destinations with those leaving in late November going towards the subtropical front and those leaving in December heading towards the sub-Antarctic front. Sub-Antarctic front travelling individuals were most impacted by factors due to the sea level, the surface current and the water depth while those travelling to the subtropical front were more impacted by the sea surface temperature and the concentration of chlorophyll a.