Jarvis Island was officially made part of the United States in 1858. People used to mine guano there, but they then abandoned it. The United States treats it as a nature reserve.
Located 25 miles south of the equator, Jarvis Island, is an uninhabited coral island located in the South Pacific Ocean. Jarvis has no known natural freshwater sources, and very little rain. This creates a very bleak, flat landscape with plants no larger than shrubs. Jarvis Island has no ports or docks, other than a reef the guano miners blew up in order for the cargo boats to be able to drop anchor. Its grass, vines and low-growing bushes are primarily a nesting, roosting, and foraging habitat for wildlife. The island has a tropical desert climate, with high temperatures in the day, constant wind, and a very hot sun. There is no evidence that the island has ever supported a native human population, but on August 30, 1913, the Amaranth was carrying a cargo of coal from Newcastle, New South Wales, to San Francisco when it crashed on Jarvis' southern shore. Ruins of ten wooden buildings, and a two-story house among them, could still be seen by the Amaranth crew, who left Jarvis aboard two lifeboats. Also, Settlers were moved to Jarvis Island in 1935 to maintain a weather station and plan a landing field. A settlement called Millersville was established on the west coast of the island because of it was the highest elevation. The Japanese shelled the island in 1942 and the men living on Jarvis were evacuated soon afterward. The United States claimed possession of Jarvis under the Guano Islands Act of 1856. The Act gave American citizens the right to claim any unclaimed, uninhabited islands for the purpose of mining guano. Because at the time guano was a very valuable asset used for fertilizer.