Many remote islands around the world have some of the most unique flora and fauna in the world. Some have species of plants and animals that are not found anywhere else and which have evolved in a specialized way. Because these islands provide a shelter from the fierce competition that species face on the mainland, species will develop that take advantage of these rare conditions. As a legacy of a unique evolutionary history, these ecosystems are irreplaceable treasures of nature. This list features some of the world’s most unique island ecosystems.
Note: The island ecosystems listed here are not necessarily islands surrounded by water, but are areas of land, isolated by natural means from the surrounding land.
Mona Island is situated in the center of the Mona Passage and administratively a part of Puerto Rico. It is the largest of three islands located in the strait, the others being Monito Island and Desecheo Island. The island was discovered by Columbus in 1493, during his second voyage to the New World. Mona Island has been a nature reserve since 1919 and uninhabited for more than 50 years. Due to the islands’ unique topography and ecology, Mona, Desecheo and Monito have been nicknamed “The Galápagos Islands of the Caribbean”. The Mona Iguana found nowhere else in the world, is considered the most spectacular species on the island. As the largest native herbivores of their ecosystems, they are essential for maintaining the balance between climate and vegetation. The island is also home to many cave drawings that were left behind by the island’s pre-Colombian inhabitants.
Sir Bani Yas is the largest, natural island in the United Arab Emirates. Over the past two decades the island has been transformed into a wildlife reserve by the late ruler of the United Arab Emirates, Sheikh Zayed. Millions of trees were planted and numerous animals species introduced to the island, including gazelle, rhea, giraffe, and ostrich. The Arabian oryx, a species of antelope, is now extinct in the wild, but Sir Bani Yas Island is home to a herd of over 400 who roam freely on the island.
Lord Howe Island is a small island in the Tasman Sea 600 kilometers (370 miles) east of the Australian mainland. Lord Howe Island is an outstanding example of an island ecosystem developed from submarine volcanic activity, having a rare diversity of landscapes, flora and fauna. The high proportion of endemic species provides a superb illustration of independent evolutionary processes at work. Almost half of the island’s native plants are endemic. One of the best known is Howea, an endemic genus of palms that are commonly known as kentia palms and make handsome houseplants. Several million are exported annually providing the only major industry on the island apart from tourism. The population of Lord Howe Island is approximately 350 people. Only 400 tourists are permitted to visit the island at any one time.
Mount Bosavi is an extinct volcano in the Southern Highlands province of Papua New Guinea. A 2009 expedition by an international team of scientists and a television crew from the BBC found more than 40 previously unknown species when they descended into the kilometer deep crater of Mount Bosavi and explored a pristine jungle habitat teeming with life that has evolved in isolation since the volcano last erupted about 200,000 years ago. Species discovered in this lost world included 16 frogs, at least 3 fish, several insects and spiders, a bat, and a giant rat, measuring 82 cm (32 inches) from nose to tail and weighing a whopping 1.5 kg (3,5 pounds).
The Ogasawara Islands are an archipelago of over 30 subtropical and tropical islands, administratively part of Tokyo but located about 1,000 kilometers (620 miles) south of the city. Until 1830, the Ogasawara Islands were uninhabited and called “Muninjima” (meaning “uninhabited island”) which transformed into the English name of Bonin Islands. Since they had been free from human activities until recently, the ecosystem of the islands has been well preserved. The Ogasawara Islands are sometimes referred to as the Galapagos of the Orient. Today there are about 2,300 people living on the islands Chichijima and Hahajima, and roughly 17,000 tourists visit the islands annually being attracted by the unique island ecosystem and the beautiful ocean.
A tepuiis a table-top mountain or mesa found in the Guiana Highlands of South America. The highest (2,772m/9094ft) and most famous tepui is Mount Roraima. Because the mountain is completely isolated from the ground forest almost one third of the species of plant life on Roraima evolved there and are unique to the plateau. Mount Roraima was made famous in 1912 when Sir Arthur Conan Doyle wrote his fictional novel entitled The Lost World. It describes the ascent of a Roraima-like mountain by an expedition in search of prehistoric plants and dinosaurs that were believed to live isolated and unchanged for millions of years on the mountains summit.
Named in 1643 for the day of its discovery, Christmas Island is a territory of Australia in the Indian Ocean. It is located 2,600 kilometers (1,600 miles) northwest of the city of Perth. It has a population of about 1,400 residents. The island’s geographic isolation and history of minimal human disturbance has led to a high level of endemism amongst its flora and fauna. The island’s most famous endemic species is probably the Christmas Island red crab. Although restricted to a relatively small area, it is estimated that up to 120 million red crabs may live on the island making it the most abundant of the 14 terrestrial crab species on Christmas Island. The annual red crab mass migration to the sea to spawn has been called one of the wonders of the natural world and takes place each year around November; after the start of the wet season and in synchronization with the cycle of the moon.
Socotra or Soqotra, an offshore territory of Yemen, is a small archipelago of four islands in the Indian Ocean. The largest island, also called Socotra, is about 95% of the landmass of the archipelago. The island is very isolated and lies some 240 kilometers (150 miles) east of the Horn of Africa and 380 kilometers (240 miles) south of the Arabian Peninsula. The long geological isolation of the Socotra archipelago and its fierce heat and drought have combined to create a unique and spectacular ecosystem. Surveys have revealed that more than a third of the 800 or so plant species of Socotra are found nowhere else. It has been described as the most alien looking place on Earth.
The Komodo National Park is a national park in Indonesia located within the Lesser Sunda Islands. The park includes the three larger islands Komodo, Padar and Rincah, and 26 smaller ones. The park was initially established to conserve the unique Komodo Dragon, the world’s largest lizard. Since then conservation goals have expanded to protecting its entire biodiversity, both marine and terrestrial. The Komodo Dragon is the world’s largest living reptile and can reach 3 meters or more in length and weigh over 70kg. As a result of their size, these lizards dominate the island ecosystems in which they live. Although Komodo dragons eat mostly carcass of dead animals, they are formidable predators and will also hunt prey including birds, and mammals. Although attacks are very rare, Komodo dragons have been known to attack humans.
The Galapagos Islands are a small archipelago of volcanic islands belonging to Ecuador in the eastern Pacific Ocean. The islands are quite remote and isolated, lying some 1000 km (620 miles) west of the South American continent. The Galapagos archipelago consists of 15 main islands, 3 smaller islands, and 107 rocks and islets distributed around the equator. The Galápagos archipelago is world renowned for its unique island ecosystems which was the inspiration for Charles Darwin’s Theory of Natural Selection. Giant tortoises, sea lions, penguins, marine iguanas and different bird species can all be seen and approached. Strict controls on tourist access are maintained in an effort to protect the natural habitats and all visitors must be accompanied by a national park-certified naturalist tour guide. One of Ecuador’s greatest destinations, the islands currently receive an average of 60,000 visitors per year.