Nazca Booby with egg in bare ground nest, Galapagos Islands, Ecuador.

A Nazca Booby guards its egg in a bare ground nest, on the Galápagos Islands, Ecuador, South America. The Nazca Booby (which has an orange beak) was formerly regarded as a subspecies of the Masked Booby (which has a yellow beak) but is now recognized as a separate species. Nazca and Masked Booby species differ in size, nesting habits, and mtDNA cytochrome b sequence data.