The Jackass Penguin (Spheniscus demersus) is a penguin endemic to the coast of southern africa. It breeds on 24 offshore islands between Namibia and Port Elizabeth.
Jackass penguins used to nest by burrowing into guano, which laid several meters deep in their habitats. Most of the nutrient-rich guano was removed for fertilizer in the 19th century. Penguins now nest in burrows in sand, under overhanging rocks, under bushes, or even in the open.
In 1930, there were appx. 1,200,000 jackass penguins. Today there are around 120,000. Reasons for the population collapse include the removal of the guano where they used to lay their eggs, harvesting of eggs for human consumption, oil pollution from oil tankers, and reduction of their food supply from commercial fishing.
Jackass penguins are efficient navigators. One oiled penguin which was rescued, cleaned and released on Robben Island in August 1971, travelled 800 km (around 500 miles) to Port Elizabeth within a month.