Gambier Islands, French Polynesia
The Living Oceans Foundation conducts coral reef research in the Gambier Islands, a small group of islands in the most remote part of French Polynesia. Also known as the Mangareva Islands, the archipelago includes five high volcanic islands and 18 smaller islets set within a deep water lagoon and surrounded by a rim of coral. Pearl farming represents a large part of the economy, but tourism and agriculture are becoming increasingly important. The conditions responsible for producing the exquisite color and quality of pearls in Gambier also support some of the most diverse and richest coral reefs in the region. The islands contain more diverse coral habitats than anything we’ve seen to date.
Our researchers spent twelve days characterizing the complex reef systems of the Gambier, a task that at times proved difficult. One genus of coral found abundantly in the area is capable of taking on different shapes, sizes, colors and appearance depending on its habitat and environmental conditions, making it hard to identify at the species level. Even under a microscope, different coral species can look alike, so our scientists often resort to genetic testing to tell species apart from one another. We found dozens of species of Acropora corals, and a species of table coral that was rare or absent at all of our other research sites in French Polynesia. Interestingly, each lagoonal reef had a different structure and collection of corals. Someday we hope to understand why.
In addition to identifying corals, we also have been collecting sediment samples to better understand how physical forces such as wind, waves and currents affect the distribution of sediment in this region. We also survey the fish on the reef to provide a full picture of the aquatic ecosystem.
Our mission also included a groundtruthing team to collect the data necessary to create detailed habitat maps of the region, as well as a ciguatera team to study the drivers of ciguatera poisoning. Researchers from Institute Louise Malardé and IRD joined us to follow up on the monitoring sites they established in 2012 and to study the algae that the illness-inducing Gambierdiscus dinoflagellates occur on. Together we established three new coral reef research sites in addition to the three sites from last year, and conducted a thorough study–the first comprehensive study of Gambierdiscus ever completed in the Gambiers.