The island of Maui is the second-largest island of the state of Hawaii at 727.2 square miles (1,883 km2), and the 17th-largest island in the United States. Maui is the largest of Maui County's four islands, which also include Molokaʻi, Lānaʻi, and unpopulated Kahoʻolawe. In 2020, Maui had a population of 168,307, the third-highest of the Hawaiian Islands, behind Oʻahu and Hawaiʻi Island. Kahului is the largest census-designated place (CDP) on the island, with a population of 28,219 as of 2020, and the island's commercial and financial hub. Wailuku is the seat of Maui County and is the third-largest CDP as of 2010. Other significant places include Kīhei, Lāhainā, Makawao, Pukalani, Pāʻia, Kula, Haʻikū, and Hāna.
The ʻelepaios are three species of monarch flycatcher in the genus Chasiempis. They are endemic to the Hawaiian Islands, and were formerly considered conspecific. They measure 14 cm long and weigh 12–18 g. One species inhabits the Big Island, another Oʻahu and the third Kauaʻi. Being one of the most adaptable native birds of Hawaiʻi, no subspecies have yet become extinct, though two have become quite rare.
Located about 2300 miles (3680 km) from the nearest continental shore, the Hawaiian Islands are the most isolated group of islands on the planet. The plant and animal life of the Hawaiian archipelago is the result of early, very infrequent colonizations of arriving species and the slow evolution of those species—in isolation from the rest of the world's flora and fauna—over a period of at least 5 million years. As a consequence, Hawai'i is home to a large number of endemic species. The radiation of species described by Charles Darwin in the Galapagos Islands which was critical to the formulation of his theory of evolution is far exceeded in the more isolated Hawaiian Islands.
Hawaiian hibiscus are seven species of hibiscus native to Hawaii. The yellow hibiscus is Hawaii's state flower. Most commonly grown as ornamental plants in the Hawaiian Islands are the non-native Chinese hibiscus and its numerous hybrids, though the native Hibiscus arnottianus is occasionally planted.
Wiliwili is a species of tree in the pea family, Fabaceae, that is endemic to the Hawaiian Islands. It is the only species of Erythrina that naturally occurs there. It is typically found in Hawaiian tropical dry forests on leeward island slopes up to an elevation of 600 m (2,000 ft).
Kazumura Cave is a lava tube and has been surveyed at 40.7 miles long and 3,614 feet deep making it the longest and deepest lava tube in the world. The cave is located on the island of Hawaiʻi on the eastern slope of Kīlauea. Kīlauea is the most recently active volcano on the Big Island. The ʻAilāʻau lava flow that contains Kazumura Cave originated from the Kīlauea Iki Crater about 500 years ago.
The poʻo-uli or black-faced honeycreeper is an extinct species of passerine bird that was endemic to the island of Maui in Hawaiʻi. It is considered to be a member of the Hawaiian honeycreepers, and is the only member of its genus Melamprosops. It had a black head, brown upper parts and pale gray underparts. This bird inhabited only the wetter, easternmost side of Maui, where it had rapidly decreased in numbers. With extinction threatening, efforts were made to capture birds to enable them to breed in captivity. These efforts were unsuccessful; in 2004, only two known birds remained, and since then, no further birds have been sighted. A 2018 study recommended declaring the species extinct, citing bird population decline patterns and the lack of any confirmed sightings since 2004, and in 2019, the species was declared extinct.
The Hawaiian lobelioids are a group of flowering plants in the bellflower family, Campanulaceae, subfamily Lobelioideae, all of which are endemic to the Hawaiian Islands. This is the largest plant radiation in the Hawaiian Islands, and indeed the largest on any island archipelago, with over 125 species. The six genera involved can be broadly separated based on growth habit: Clermontia are typically branched shrubs or small trees, up to 7 metres (23 ft) tall, with fleshy fruits; Cyanea and Delissea are typically unbranched or branching only at the base, with a cluster of relatively broad leaves at the apex and fleshy fruits; Lobelia and Trematolobelia have long thin leaves down a single, non-woody stem and capsular fruits with wind-dispersed seeds; and the peculiar Brighamia have a short, thick stem with a dense cluster of broad leaves, elongate white flowers, and capsular fruits. The relationships among the genera and sections remains unsettled as of April 2022.
Hibiscadelphus is a genus of flowering plants that are endemic to Hawaiʻi. It is known by the Native Hawaiians as hau kuahiwi which means "mountain Hibiscus". The Latin name Hibiscadelphus means "brother of Hibiscus". It is distinctive for its peculiar flowers, which do not fully open. Hibiscadelphus is in the family Malvaceae, subfamily Malvoideae. Several of the species in this small genus are presumed extinct, as a result of coextinction with their primary pollinators, the Hawaiian honeycreepers.
The Maui parrotbill or kiwikiu is a species of Hawaiian honeycreeper endemic to the island of Maui in Hawaii. It can only be found in 50 square kilometres (19 sq mi) of mesic and wet forests at 1,200–2,150 metres (3,940–7,050 ft) on the windward slopes of Haleakalā. This species is critically endangered, with an estimated population in 2016 of 250-540 individuals, but more recent estimates of less than 150 individuals. Fossil evidence indicates that the bird could at one time be seen in dry forests at elevations as low as 200–300 metres (660–980 ft), as well as on the island of Molokaʻi.
Santalum haleakalae, known as Haleakala sandalwood or ʻIliahi in Hawaiian, is a species of flowering tree in the sandalwood family, that is endemic to the islands of Maui, Lanai, and Molokai in the Hawaiian Islands, part of the United States. It grows in subalpine shrublands at elevations of 1,900 to 2,700 m, especially on the slopes of Haleakalā.
Pleistodontes froggatti is a species of fig wasp which is native to Australia. It has an obligate mutualism with the Moreton Bay Fig, Ficus macrophylla, the species it pollinates. Outside Australia, populations have become established in Hawaii and New Zealand where it was either accidentally introduced or arrived by long-distance dispersal.
Vespula pensylvanica, the western yellowjacket, is a Nearctic species of wasp in the genus Vespula. It is native to regions of North America, largely in areas with northern temperate climates. Its reproductive behavior is constrained by cold weather, which successfully reduces the number of western yellowjackets in cold months. However, in the absence of cold weather, this wasp's population can explode. The western yellowjacket has become particularly invasive in the Hawaiian Islands, resulting in their label as a major pest.
Omiodes blackburni, the coconut leafroller, is a species of moth in the family Crambidae. It is endemic to the Hawaiian islands of Kauai, Oahu, Molokai, Maui, Lanai and Hawaii. The species was first described by Arthur Gardiner Butler in 1877.
Scotorythra paludicola, the koa looper moth, is a moth of the family Geometridae. It was first described by Arthur Gardiner Butler in 1879. It is endemic to the Hawaiian islands of Kauai, Oahu, Maui and Hawaii.
Hyposmocoma alliterata is a species of moth of the family Cosmopterigidae. It was first described by Lord Walsingham in 1907. It is endemic to the Hawaiian islands of Oahu, Molokai, Maui and Hawaii. This species is thought to range from the lowlands to the highlands, where it is most abundant.
Neritona granosa is a species of freshwater snail with an operculum, an aquatic gastropod mollusk in the family Neritidae, the nerites.
Udara blackburni, the Koa butterfly, is a butterfly in the family Lycaenidae that is endemic to Hawaiʻi. It is also known as Blackburn's butterfly, Blackburn's bluet, Hawaiian blue or green Hawaiian blue.
Schrankia howarthi is a species of moth of the family Erebidae. It normally occurs within the twilight to dark zone areas of lava tubes on the islands of Maui and Hawaii, however, it is sometimes found flying on the surface of both islands. The paler morph may be restricted to the dark zone of lava tubes.
Hypocala velans is a moth of the family Erebidae. It was first described by Francis Walker in 1857. It is endemic to the Hawaiian islands of Kauai, Oahu, Molokai, Maui and Hawaii. It was thought to be extinct until a single specimen was collected at Puʻu Waʻawaʻa in April 1995.
