Navassa Island is a small uninhabited Caribbean island 74 km off the coast of Haiti. Both the US and Haiti claim sovereignty over the island, though Haiti claims it in it's constitution. Discovered in 1498 and explored in 1504 as part of Columbus's expedition when he became stranded on Jamaica and sent a canoe to Hispaniola; the canoes ran into the island on the way and two Spaniards and several Indians who arrived on the island drank contaminated water killing most of the group. The island was avoided until 1857 when it was claimed by the US as part of the Guano Islands Act despite an earlier Haitian claim. Working conditions were very harsh on the island, manually moving over a ton guano from mines via rail cars to the landing point at Lulu Bay which sacked the guano for transport on the S.S. Romance. In 1889 the workers started a rebellion that killed several supervisors and lead to a series of court cases that affirmed the constitutionality of the Guano Act. The island was abandoned in 1898 during the Spanish-American war forced the operator, Navassa Phosphate Company of Baltimore to file for bankruptcy. In 1917 a lighthouse was built since the island posed a hazard for ships entering the newly built Panama Canal. The island has remained uninhabited, save a few Haitian fishermen that camp now and again, though it is highly coveted by amateur radio operators seeking a DX call-sign of KP1. The island has been bounced around several federal agencies until 1999 when the United States Fish and Wildlife Service cataloged it as a National Wildlife Refuge. In 2009 NOAA's Southeast Fisheries Science launched an expedition to catalog the flora and fauna of the reefs of the island, including a few feral cats roaming on the island.