[12][13] From 1801 to 1867, the successive constitutions of Haiti claimed sovereignty over adjacent islands, both named and unnamed, although Navassa was not specifically enumerated until 1874.

[3] Haiti protested the annexation, but on July 7, 1858, U.S. President James Buchanan issued an Executive Order supporting the American claim, calling for military action to enforce it.

In November 1857, Duncan transferred his discoverer's rights to his employer, an American guano trader in Jamaica, who sold them to the newly formed Navassa Phosphate Company of Baltimore.

The workers dug out the guano by dynamite and pick-axe and hauled it in rail cars to the landing point at Lulu Bay, where it was put into sacks and lowered onto boats for transfer to the Company barque, the S.S.

[18] In September 1875, the fierce 1875 Indianola hurricane swept over the island, destroying much of the company's infrastructure, including the rail line and workers' homes.

[19] Hauling guano by muscle power in the fierce tropical heat, combined with general disgruntlement with conditions on the island, eventually contributed to a riot in 1889, in which five supervisors died.

The defense tried to build a case on the contention that the men acted in self-defense or the heat of passion and even claimed that the United States did not have jurisdiction over the island.

The cases, including Jones v. United States, went to the U.S. Supreme Court in October 1890, which ruled the Guano Act constitutional.

A grass-roots petition driven by black churches around the country, also signed by white jurors from the three trials, reached President Benjamin Harrison, who mentioned the case in the 1891 State of the Union Address.

In 1898, during the Spanish–American War, the Phosphate Company had to abandon its operations on Navassa due to its proximity to Spanish Cuba and Puerto Rico.

Company president John H. Fowler noted that the war made it impossible to find ships to deliver supplies to the island and expected his workers to be evacuated by June.

Maryland senator Arthur Pue Gorman called for a naval warship to escort supply ships to the island to help evacuate workers.

[23] A dispute over the sale hampered efforts to restart mining on the island and left four contract workers virtually abandoned on Navassa from December 1900 to May 1901.

As part of the Parish–Smithsonian Expedition to Haiti in 1930, Smithsonian naturalists Alexander Wetmore and Waston Perrygo stopped at Navassa to document and collect examples of the island's birds and other terrestrial and marine wildlife.

[32] In 1997, an American salvager, Bill Warren, claimed Navassa to the Department of State based on the Guano Islands Act.

The department's opinion said that Navassa is and remains a U.S. possession "appertaining to" the United States and is "unavailable to be claimed" under the Guano Islands Act.

[3] A 1998 scientific expedition led by the Center for Marine Conservation in Washington, D.C., described Navassa as "a unique preserve of Caribbean biodiversity.

Due to hazardous coastal conditions and to preserve species habitat, the refuge is closed to the general public, and visitors need permission from the Fish and Wildlife Service to enter its territorial waters or land.

[48] There were eight species of native reptiles, all of which are believed to be, or to have been, endemic to Navassa Island: Comptus badius (an anguid lizard), Aristelliger cochranae (a gecko), Sphaerodactylus becki (a gecko), Anolis longiceps (an anole), Cyclura cornuta onchiopsis (an endemic subspecies of the rhinoceros iguana), Leiocephalus eremitus (a curly-tailed lizard), Tropidophis bucculentus (a dwarf boa), and Typhlops sulcatus (a tiny snake).

[49] Of these, the first four remain common, with the next three likely extinct, and the last being possibly extirpated[49] due to feral cats, dogs and pigs inhabiting the island.

[50] The island, with its surrounding marine waters, has been recognized as an Important Bird Area (IBA) by BirdLife International because it supports breeding colonies of red-footed boobies and magnificent frigatebirds, as well as hundreds of white-crowned pigeons.