Named Isla de Aves in Spanish, (meaning “Island of the Birds”) Aves Island lies west of the Lesser Antilles in the Caribbean. It provides a nesting site to green sea turtles (Chelonia mydas) and, of course, birds. Because the abundant bird droppings, known as guano, could be used in fertilizer and gunpowder, guano miners worked on the island until they depleted the supply. Since its discovery by Europeans, likely in the late 16th century, Aves Island was subsequently claimed by several European nations. The island is currently claimed by Venezuela, although disputes about ownership of the island, and the surrounding exclusive economic zone in the Caribbean, continue today.
Howland Island is a United States possession located in the north Pacific between Australia and the Hawaiian Islands. Prior to 1890, organic nitrate (guano) was mined from the island by both the United States and the British. This tiny island (1.6 km²) is currently part of the U.S. National Wildlife Refuge system, and provides nesting areas and forage for a variety of birds and marine wildlife. The island is composed of coral fragments and is surrounded by an active fringing reef. White breakers encircling the island indicate the position of the reef. Astronauts aboard the International Space Station photograph numerous reefs around the world as part of a global mapping and monitoring program.
The small island of Blanquilla is named for its white sand beaches, visible in this astronaut photograph as a bright border along the northeastern–eastern shoreline. Surface currents extending from the western coastline of the island are caused by easterly trade winds. This dominant wind has also caused movement of beach sand to form white “fingers” extending inland along the east coast.