The Galapagos Penguin (Spheniscus mendiculus) is a penguin endemic to the Galapagos Islands. It is the only penguin that lives north of the equator in the wild. It can survive due to the cool temperatures resulting from the Humboldt Current and cool waters from great depths brought up by the Cromwell Current. The Galapagos Penguin is one of the banded penguins, the other species of which live mostly on the coasts of Africa and mainland South America.
The species is endangered, with an estimated population size of around 1,500 individuals in 2004, according to a survey by the Charles Darwin Research Station. The population underwent an alarming decline of over 70% in the 1980s, but is slowly recovering. It is therefore the rarest penguin species (a status which is often falsely attributed to the Yellow-eyed Penguin). Population levels are influenced by the effects of the El Niño Southern Oscillation, which reduces the availability of shoaling fish, leading to low reproduction or starvation. However, anthropogenic factors (e.g. oil pollution, fishing by-catch and competition) may be adding to the ongoing demise of this species. On Isabela Island, introduced cats, dogs, and rats attack penguins and destroy their nests. When in the water, they are preyed upon by sharks, fur seals, and sea lions.