shore. A forested islet, Constance Island, also "Constance Islet", is located about off the southeast coastline, at the edge of the reef. The 2004 Indian Ocean earthquake tilted the tectonic plate under the island, lifting it by . Large tracts of the surrounding coral reefs were exposed and became permanently dry land or shallow lagoons, extending all the island's boundaries – by as much as on the west and south sides – and uniting Constance Islet with the main island. Flora and fauna The island is largely covered in tropical and subtropical moist broadleaf forest. Due to the lack of surveys, the exact composition of the terrestrial flora and fauna remain unknown. In his 1880 expedition to the island, Maurice Vidal Portman reported an open, "park-like" jungle with numerous groves of bulletwood (Manilkara littoralis) trees, as well as huge, buttressed specimens of Malabar silk-cotton tree (Bombax ceiba). Indian boar (Sus scrofa cristatus) are apparently found on the island and a major food source for the Sentinelese, with reports by Portman referring to a "huge heap" of pig skulls near a Sentinelese village. The IUCN Red List lists North Sentinel as being an important habitat for coconut crabs (Birgus latro), which have been otherwise extirpated from most of the other Andaman Islands except from South Sentinel and Little Andaman. North Sentinel Island, along with South Sentinel, is also considered a globally Important Bird Area (IBA) by BirdLife International, as despite the lack of surveys, the pristine habitat likely supports a diversity of birdlife. The marine life surrounding the island have also not been well surveyed. A large coral reef is known to circle the island, and mangroves are also known to fringe its banks. A c. 1999 report from divers near the island indicate that the reefs around the island were bleached in the 1998 El Niño, but had since seen new growth of coral. Sharks have allegedly also been seen in the waters off the island. Sea turtles likely also occur near the island, as Portman referred to them also being a major food source for the Sentinelese and one was sighted on a 1999 survey of the surrounding waters. Dolphins were also sighted on the same survey. History The Onge, one of the other indigenous peoples of the Andamans, were aware of North Sentinel Island's existence; their traditional name for the island is Chia daaKwokweyeh. They also have strong