This slideshow features all 18 species of penguin in the world. As you can read in this article, author Charles Bergman and his wife, Susan Mann, have seen all 18 of the species. The captions below the photos list the places where the couple first saw each species and the dates on which they saw them. The conservation status for each species is from BirdLife International.
Above: Galápagos Penguin: Endangered; Rábida Island, Galápagos Islands; January 24, 2003
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