Rockhopper penguin

[1] Males and females cannot be distinguished visually, so a DNA test is conducted by taking a feather from the bird to determine its gender.

[2] Some characteristics that differentiate them from the other penguins are their red eyes, orange beak, pink webbed feet, and the yellow and black spiky feathers they have on their head.

The difference in mating signals found between the subspecies E. chrysocome (southern) and E. moseleyi (northern) seems to have occurred quickly, thus these behavioral changes are enough to isolate these taxa.

The southern rockhopper breeds on the Falkland Islands, Argentina and Chile, with breeding colonies around Cape Horn in South America, and Gough, Prince Edward, Marion, Crozet, Kerguelen, Heard, Macquarie, Campbell, Auckland and Antipodes Islands in the southern Indian Ocean.

Eastern rockhopper penguins are mostly found breeding on Campbell Island in New Zealand, but their numbers have declined immensely.

The rockhopper penguin's diet consists of krill and small crustaceans, which may include shrimp, crabs, lobsters or crayfish.

The mid-Pleistocene climatic transition was associated with the southward migration of frontal positions and islands became surrounded by subtropical water masses, resulting in a split between Northern and Southern rockhopper penguins.

[12] Chicks and eggs are eaten by many birds including giant petrels, skuas, sheathbills and various types of gulls.

[1] The cause of this decline is mainly unknown, but scientists have speculated that humans are involved, mostly by commercial overfishing, oil exploitation, and pollution.

Oil spills have impacted many penguin species since the conversion of shipping from sail and coal propulsion to liquid-based fuels in the early 20th century.