Key Highlights
- The reef is the longest continuous barrier reef in the world, extending over 1,500 kilometers.
- It encircles the main island of Grande Terre and several smaller islets, forming a 24,000‑km² lagoon.
- More than 2,300 fish species have been recorded, including rare marine mammals such as dugongs and humpback whales.
- Despite its overall health, sections suffer from sedimentation and pollution linked to mining and agricultural runoff.
- Local community groups and UNESCO protection work collaboratively to monitor and preserve the ecosystem.
Detailed Insights
Geography and Scale. Spanning approximately 1,500 km, the reef traces the coastline of Grande Terre, reaching up to 200 km from the shore in the northwest. The lagoon it shelters covers about 24,000 km² with a depth averaging 25 m.
Biological Diversity. The reef hosts 2,328 fish species across 248 families, alongside over 2,000 mollusk species. It serves as a critical rest stop for humpback whales and a nesting site for green sea turtles.
Threats. Nickel mining, deforestation and agricultural activities introduce fine sediments and chemical runoff, smothering reef structures and threatening local mangrove buffers. Continuous sedimentation could lead to the loss of sections of the reef.
Conservation Efforts. Since its designation as a UNESCO World Heritage Site in 2008, thirteen local stakeholder committees—fisherfolk, tribal leaders and tourism operators—monitor reef health, enforce regulations, and promote sustainable practices.