Galapagos Penguin

The penguins are confined to the archipelago, foraging in the cool Cromwell Current during the day and returning to the land at night. They eat small schooling fish, mainly mullet and sardines, and sometimes crustaceans. They normally range only a few kilometers from their breeding sites, depending on the cold, nutrient-rich currents to bring them food. Air temperatures in the Galápagos remain in the range 15–28 °C (59–82 °F). During El Niño seasons, the penguins defer breeding because their food becomes less abundant; this makes the chances of raising offspring successfully unfavorable compared to the chances of dying in the attempt. This was especially detrimental during the 1982-83 El Niño, where a decline in population of 77% was observed. The penguins usually breed when the sea surface temperature is below 25 °C (77 °F). The strong tropical sun is problematic for this species. Their primary means of cooling off is going in the water, but other behavioral adaptations for thermoregulation come into play when they must remain on land. One method involves stretching out their flippers and hunching forward to keep the sun from shining on their feet, which exchange heat rapidly because they have high blood flow and lack insulation. Another method is to pant, using evaporation to cool the throat and airways. Galápagos penguins protect their eggs and chicks from the hot sun by keeping them in deep crevices in the rocks.

Ninety percent of Galápagos penguins live on Fernandina Island and the west coast of Isabela Island, in the western part of the archipelago, but small populations also occur on Santiago, Bartolomé, northern Santa Cruz, and Floreana. The northern tip of Isabela crosses the equator, meaning that some Galápagos penguins live in the northern hemisphere, the only penguins to do so.

ENDANGERED. Global population estimated at fewer than 2000 individuals, of which c. 95% in W Galapagos (on Isabela I and Fernandina I).