Aldabra is a group of islands.
It sits in the sea near Africa. It has a big, shallow pool of water.
Big tortoises live there. They are a wonder of nature. Do you want to see them?
Aldabra is a group of islands.
It sits in the sea near Africa. It is part of the Seychelles.
The place has a very large coral reef. It also has a big, shallow pool of water.
Giant tortoises live on these islands. They are a wonder of nature.
Long ago, people hunted these big tortoises. Now, the islands are a safe place for them. This helps the animals live well.
Many scientists visit to study the plants and animals. It is a very special place to see.
Aldabra is a very special place in the Indian Ocean.
It sits east of Africa. It is part of the Seychelles. Aldabra is the second-largest coral atoll in the world. An atoll is a ring of islands built on a coral reef.
This atoll has the world's largest raised coral reef. It also has a large, shallow lagoon. This lagoon is mostly dry when the tide is low.
Many animals live here. The most famous are the giant tortoises.
Long ago, people hunted these tortoises for food. By the year 1900, they were nearly gone. Now, the islands are a protected nature reserve. This helps the tortoises and other animals stay safe. Scientists visit to study the plants and animals. They want to learn about the many life forms here. There are even sharks in the water.
People visit on guided tours to keep the land safe.
Aldabra is a truly amazing place in the Indian Ocean.
It sits east of Africa and is part of the Seychelles. This area is known as the Outer Islands. It is located 1,120 km southwest of Victoria on Mahé Island. Aldabra is the second-largest coral atoll on Earth. The largest one is called Kiritimati. This atoll is special because it has the world's largest raised coral reef. It is a ring of islands built on a reef. Around the rim, you will find a large, shallow lagoon.
This lagoon is about two-thirds dry when the tide is low.
The land is made of reef limestone from the Pleistocene age. This limestone has unique coral shapes called "champignon." These shapes have two layers of different crystals. The reef rises above the sea to form a rim. This rim has low cliffs and jagged pinnacles. There are three passages that connect the lagoon to the sea. These passages can be up to 10 meters deep. The water in the lagoon is usually quite shallow. However, the tidal currents in the passages are very strong. The total land area of the atoll is 31 square kilometers. The whole area, including the lagoon, is 255 square kilometers.
People have known about Aldabra for a very long time. Arab seafarers gave it its name because of the harsh environment. They called it Al-Hadra or Al-Khadra. Portuguese maps from the 1500s show the name. In 1742, the French used the islands to find giant tortoises. Later, Great Britain took control of the islands in 1810. In 1888, the first human settlement was started. People tried to grow coconuts, cotton, and sisal there. These farms failed because there was no fresh water on the atoll. Villagers had to build large tanks to store water.
Nature has faced many changes on these islands. In the 1800s, people hunted tortoises for food and trade. By 1900, the tortoises were nearly gone. It was hard to find even one! In the 1960s, there were plans to build a military base. Scientists protested to stop this plan. This event was called the "Aldabra Affair." Because of these protests, the atoll was protected instead. The Royal Society of London began research there in the 1970s. In 1982, Aldabra became a UNESCO World Heritage Site.
Today, Aldabra is a vital place for science. It is a Special Nature Reserve in the Seychelles. Many different living things call it home. You might see a Souimanga sunbird.
You might even see a blacktip reef shark in the water.
The giant tortoises are still the most famous residents. Scientists study the plants and animals to help them thrive. There are still challenges like plastic pollution and invasive species. To keep the ecosystem safe, tourism is very limited. Visitors can only visit through special guided tours.
Aldabra is a remarkable geographic feature located in the Indian Ocean.
It sits east of the African continent. The atoll is part of the Aldabra Group of islands. These islands belong to the Outer Islands of the Seychelles. It is situated 1,120 km southwest of Victoria on Mahé Island. Aldabra is the second-largest coral atoll in the world. The largest atoll is Kiritimati. It is also famous for being the world's largest raised coral reef. This unique structure makes it an essential site for global biodiversity.
The physical structure of the atoll is defined by its geology. It consists of reef limestone from the Pleistocene age. This limestone features irregular coral formations known as "champignon." These formations possess two layers of varying crystallization stages. The reef rises above sea level to form a distinct rim line. This rim includes low cliffs with deep notches and jagged pinnacles. The atoll is long in both east-west and north-south directions. It contains a large, shallow lagoon that covers 255 square kilometers.
The lagoon is about two-thirds dry during low tide. The total land area of the islands is 31 square kilometers. Three passages connect the lagoon to the open sea. These passages can reach depths of 10 meters. Tidal currents in these passages are very strong.
Aldabra's history is marked by human interaction and environmental change. Arab seafarers originally named the atoll Al-Hadra or Al-Khadra. They chose this name because of the harsh, sun-baked environment. Portuguese navigators visited the area in 1511. In the mid-18th century, the atoll became a dependency of the French colony of Réunion. Explorers used the islands to capture giant tortoises. Great Britain took possession of Aldabra in 1810. Later, the islands became part of Mauritius and the Seychelles. The first human settlement was established in 1888. This settlement aimed to exploit natural resources through various plantations.
Early attempts at human habitation faced significant geographic challenges. Settlers tried to grow crops like coconuts, cotton, and sisal. These agricultural ventures failed because the atoll has no surface freshwater. To survive, villagers built large rectangular water storage structures near every building. They also built a chapel and a two-roomed jail. Some villagers even used a crushing mill on Picard Island. This mill was used to crush tortoise bones for commercial purposes. By 1900, the giant tortoise population was nearly extinct. Hunters often spent three days searching to find just one tortoise. However, a man named James Spurs helped save them by banning killing in 1891.
In the mid-20th century, Aldabra became a center for international political debate. During the 1960s, the British government considered building an RAF military base. They invited the United States to help fund this project. At the same time, the BBC wanted to use the site for a transmitter. This would have broadcast the BBC Overseas Service to Africa. These plans sparked a massive international protest by scientists. This period is known as the "Aldabra Affair." Environmental lobbyists led by Julian Huxley successfully stopped the military plans. Instead of a base, the atoll received full environmental protection.
Today, Aldabra is a vital ecological wonder and a scientific research site.
The Royal Society of London conducted research there starting in the 1970s. Later, the Seychelles Islands Foundation assumed management in 1979. Aldabra was declared a Special Nature Reserve in 1981. It became a UNESCO World Heritage Site on November 19, 1982. The atoll is a critical breeding ground for many species. You can find the Souimanga sunbird among the plants.
In the waters, the blacktip reef shark is a notable resident.
Preserving this delicate ecosystem remains a constant priority for conservationists. The atoll faces modern challenges like plastic pollution and invasive species. For example, ship rats were introduced to the islands before 1870. House geckos were also noted starting in the 1970s. To protect the biodiversity, tourism is strictly limited. Visitors can primarily access the atoll through guided tours. This management ensures that Aldabra remains one of the most undisturbed raised coral atolls in the world. It continues to serve as a living laboratory for studying the natural world.
Where will your curiosity go next?
🖼️ Images & Media (5)
More to explore
✨ What else?
Related topics you might enjoy
🔬 Go deeper
More advanced topics to explore
🪜 Step back
Simpler topics to build understanding
What is Nepedia?
A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.