Galápagos Big 15: Penguins
The Galápagos penguins (Spheniscus mendiculus) are another example of the extraordinary biodiversity of the islands, thanks to their unique location. The intersection of the cold Humboldt Current and cold water from the depths of the Cromwell Current allow these sub-Antarctic birds to survive in tropical Pacific waters, plus providing unusually rich marine conditions. Penguins breed only during the cooler times of the year, as the colder temperature is associated with more food for these highly monogamous, unique birds.
This third smallest of all penguins is endemic to these islands, found in larger numbers in the west on Fernandina and Isabela, but smaller colonies live in Floreana, Bartolomé and Santiago Island too. A total population of a little over 1,000 individuals makes this the rarest penguin in the world; hence, it is classified as endangered by the IUCN.
Flightless marine birds are particularly susceptible to changes in sea temperature, and sea temperature changes are the norm in Galápagos. To cope, these penguins have developed a series of adaptations. Counter-current heat exchange is enabled by a special setting of veins and arteries in places like the face, axillae and legs to allow heat to dissipate, more so as the overall plumage is less dense and the bird is small. Its greater surface area relative to its total size gives it a larger surface from which to lose heat when on land. Behavioural adaptations to deal with heat also include turning the lighter side onto or away from the sun, panting, or simply hopping into the water or entering lava crevices to enjoy the shade.
Meet this penguins on board our Yacht Sea Lion when we visit Bartolomé Island every Saturday.