The only species of penguin to breed in tropical waters, the Galapagos penguin (Spheniscus mendiculus) is endemic to the Ecuadorian archipelago known as the Galapagos islands. They are also the only penguin which lives north of the equator in the wild. They can survive in their tropical habitat due to the cool waters brought about by the Humboldt current which flows along the western coast of South America.
This flightless bird is the second smallest species of penguin (after the aptly named Little Penguin) and nests in rock crevices found across their island habitat. They can be identified by their bands of black and white colouration. As with all species which live on the Galapagos islands, this penguin has been forced to adapt to this extremely niche environment. Their populations are mainly found along the coast of Fernandina Island and the west coast of Isabela Island where they feed on small fish, sardines and crustaceans. When in the water, their small size makes them a tasty meal for sharks, fur seals and sea lions but the penguin’s nimble and swift nature can often help them escape their doom.
One of the main struggles for the Galapagos penguin is the warm weather and blazing sun so they have evolved to use methods of thermoregulation to help them survive. For instance, they stretch out their flippers and hunch forward to keep the sun from shining on their feet, since they can lose heat from their flippers due to the blood flow there. This is an example of a behavioural adaptation which makes them better suited to their environment. They also pant, using evaporation to cool their throat and airways. Although, if they get too cold, they can always go for a quick swim in the cold ocean waters surrounding their home. Cleverly, they lay their eggs in deep rock crevices to protect them from the hot weather.
Sadly, this unique bird is classified as an endangered species by the IUCN, and the WWF estimates that their population is fewer than 2000 individuals, meaning the Galapagos penguin has the smallest population size of any penguin species. Threats to their species include over-fishing, oil-spills, becoming caught in fishing nets and the introduction of foreign animals to the archipelago such as dogs, cats, and rats which attack the penguins and annihilate their nests.