unincorporated territory of the United States in the central Pacific Ocean, about 825 miles (1,330 km) southwest of Honolulu. It consists of four small islands on a raised coral atoll formation that are partially enclosed on the north and west by a 7.5-mile (12-km) semicircular reef. Two of the four-Johnston and Sand islands-are natural, and the other two are man-made by dredging. The islands' combined land area is about 1.1 square miles (2.8 square km), Johnston Island constituting the vast bulk of the total. Rainfall is sparse, and there are no sources of fresh water. Vegetation is limited to bunchgrass, herbs, and some introduced palm trees. The surrounding waters are home to a large variety of fishes and to other marine animals such as green sea turtles; in addition, vast numbers of seabirds visit the islands
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