Penguin, Yellow-eyed

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Penguin, yellow-eyed

Megadyptes antipodes

phylum: Chordata

class: Aves

order: Sphenisciformes

family: Spheniscidae

status: Endangered, IUCN

range: New Zealand

Description and biology

Penguins are flightless sea birds. Like other penguins, the yellow-eyed penguin is mainly gray and white in color. What separates this penguin from others are its striking crown of yellow feathers and its bright, yellow eyes. Its cheeks are pale yellow, and its bill and feet are beige.

An average adult yellow-eyed penguin can measure 30 inches (76 centimeters) long and weigh 11 pounds (5 kilograms). Its torpedo-shaped body allows the bird to travel swiftly in water, where it catches squid, crustaceans (such as crabs and shrimp), and small fish. On land, the penguin shuffles along on well-used paths from the sea to grassy cliffs and inland forests. It often walks more than 0.5 mile (0.8 kilometer) a day.

Penguins are normally very social, but the yellow-eyed penguin is sometimes only mildly so. It may live in colonies

made up of only a few birds or as many as 50 pairs. Penguins tend to mate for life. The breeding season for yellow-eyed penguins lasts only from late September to mid-October. Their nests, made of sticks and coarse grass, are located in holes in the ground, among rocks, or within stunted trees or shrubs.

A female yellow-eyed penguin lays 2 eggs, the second of which is laid 4 days after the first. Both parents incubate (sit on or brood) the eggs for about 42 days. Upon birth, the chicks are covered in fine, short, dark brown feathers. As they grow older, their distinctive yellow crown begins to emerge. When they are about six weeks old, the chicks are left alone in the nest, and they may venture out to sea shortly thereafter.

Habitat and current distribution

The yellow-eyed penguin is found in New Zealand on South, Stewart, Codfish, Campbell, and Auckland Islands. Biologists (people who study living organisms) estimate that between 5,000 and 6,000 of these penguins currently exist.

The birds prefer to inhabit coastal waters. They feed in inshore waters and roost (rest or sleep) on sandy beaches.

History and conservation measures

The primary threat to the yellow-eyed penguin has been the disturbance or destruction of its nesting habitat. Much of its habitat has been converted into farmland. Other areas have been degraded or worn down by grazing livestock from nearby farms. Predators that have been brought into the area by humans (such as dogs, cats, and pigs), have taken their toll on the bird's population.

Yellow-eyed penguins have also suffered at the hands of fishermen. The birds often become tangled in fishing nets, and many have died as a result. Pesticides and other forms of pollution have also killed many yellow-eyed penguins by contaminating their food sources.

Wildlife organizations in New Zealand have purchased nesting sites to preserve what remains of the yellow-eyed penguin's habitat. Within these sites, they have removed introduced predators and have begun to replant trees and other types of vegetation.