Moyenne Island is a small island (9.9 ha or 24 acres) in the Sainte Anne Marine National Park off the north coast of Mahé, Seychelles. Since the 1970s onwards, it has been a flora and fauna reserve. From 1915 until the 1960s, the island was abandoned until its purchase by Brendon Grimshaw for £8,000 (about $22,000). He was a newspaper editor from Dewsbury in Yorkshire, England.

Grimshaw was the only inhabitant of the island until his death in July 2012. The island is now a national park and can be visited as part of organized trips.

Moyenne Island, named after the French word for "middle", has a rich history. Pirates allegedly used the island in the 18th and 19th centuries, and two "pirate graves" remain. Philippe Georges owned the island from 1946 to 1962, living there with his wife Vera before moving to Mahé. The island features a viewpoint and beach named after Vera.

In 1962, Brendon Grimshaw bought the island from Philippe Georges for £8,000 (equivalent to £216,000 in 2023). Grimshaw and René Antoine Lafortune transformed the island by planting 16,000 trees, building nature paths, and introducing Aldabra giant tortoises. Their goal was to create an island of exceptional beauty, now home to diverse plant and bird life, and nearly 50 giant tortoises.

After 20 years of persistence, Grimshaw and Lafortune succeeded in making Moyenne Island a national park in its own right. The island is now known as Moyenne Island National Park, separate from the surrounding Sainte Anne Marine National Park. Following Grimshaw's death in 2012, his friend Suketu Patel oversees the Moyenne Island Foundation, managing the island and fulfilling Grimshaw's vision of preserving the island's natural beauty.

The island remains largely undeveloped, with a small restaurant and museum dedicated to Grimshaw. The fifty Aldabra giant tortoises roam freely, and the island is a testament to Grimshaw's dedication to conservation.

The island belongs to Mont Fleuri District.

Today, the island's main industry is tourism, and it is known for its beaches. Behind the restaurant is the local warden's house.

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  Map 1
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  Moyenne Island
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  Mahé Island View
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  Moyenne island

• Media related to Moyenne at Wikimedia Commons
• Moyenne Island Guide