NATURAL HISTORY

ROCKHOPPER PENGUINS } Eudyptes chrysocome chrysocome, Eudyptes chrysocome chrysocome, Eudyptes moseleyi
FAMILY: Spheniscidae

Based on recent genetic information, the rockhopper penguin species complex includes the northern rockhopper penguin (Eudyptes moseleyi) and the southern rockhopper penguin (Eudyptes chrysocome). The southern rockhopper penguin species can be further divided into the southern rockhopper (Eudyptes chrysocome chrysocome) and eastern rockhopper (Eudyptes chrysocome filholi) subspecies.

DESCRIPTION: At about 21.7 inches in length and 5.5 pounds, rockhoppers are the smallest of the yellow-crested, black and white penguins. They have red eyes, white underparts, slate-gray upperparts, and a straight, bright yellow eyebrow ending in long yellow plumes behind the eye. The top of the head has spiked black feathers.

HABITAT: These penguins live on rocky shorelines and make burrows and nests in high grasses called tussocks.

RANGE: The southern rockhopper subspecies breeds on the Falkland Islands and in southern Chile and southern Argentina. The eastern rockhopper penguin breeds on Prince Edward Island and the Marion Islands in South Africa, the Crozet Islands and Kerguelen Islands in the French Southern Territories, Australia's Heard and Macquarie islands, and the Antipodes Islands and Campbell and Auckland islands in New Zealand. The northern rockhopper penguin breeds on Gough Island and Tristan da Cunha in the southern Atlantic Ocean and the St. Paul Islands in the southern Indian Ocean. Range Map

MIGRATION: These penguins leave the breeding colony in late summer or fall and spend three to five months at sea, where they forage for food.

BREEDING: Rockhopper penguins usually breed in the early spring or late summer in vast colonies. They lay up to two eggs, with the first, smaller egg usually being lost. Eggs are incubated for four months by the male, who fasts or is nourished by the female.

LIFE CYCLE: The average rockhopper lifespan is about 10 years in the wild.

FEEDING: Rockhoppers primarily eat krill, but will also eat other crustaceans as well as squid.

THREATS: Researchers conclude that the declines observed in rockhopper penguin populations are a result of reduced prey abundance caused by global warming. In addition, rockhoppers suffer from the effects of overfishing and oil pollution.

POPULATION TREND: Although the world population of all rockhoppers is currently estimated at around 1.5 million pairs, the population has decreased by several million pairs since the early part of the 20th century, and it is estimated to have decreased by 30 percent in the past 30 years.

Photo by Pablo Fernicola/Flickr