Delineating the Coral Triangle

Abstract

Spatial analyses of coral distributions at species level delineate the Coral Triangle and provide new insights into patterns of diversity and endemism around the globe. This study shows that the Coral Triangle, an area extending from the Philippines to the Solomon Islands, has 605 zooxanthellate corals including 15 regional endemics. This amounts to 76% of the world’s total species complement, giving this province the world’s highest conservation priority. Within the Coral Triangle, highest richness resides in the Bird’s Head Peninsula of Indonesian Papua which hosts 574 species, with individual reefs supporting up to 280 species ha−1 . Reasons for the exceptional richness of the Coral Triangle include the geological setting, physical environment and an array of ecological processes. These findings, supported by parallel distributions of reef fishes and other taxa, provide a clear scientific justification for the Coral Triangle Initiative, arguably one of the world’s most significant reef conservation undertakings.

Introduction

“If we look at a globe or a map of the Eastern Hemisphere, we shall perceive between Asia and Australia a number of large and small islands, forming a connected group distinct from those great masses of land and having little connexion with either of them. Situated upon the equator, and bathed in the tepid water of the great tropical oceans, this region enjoys a climate more uniformly hot and moist than almost any other part of the globe, and teems with natural productions which are elsewhere unknown.” So begins Alfred Russel Wallace’s seminal book The Malay Archipelago, first published in 1869 (Wallace, 1869) and destined to become one of the foundations of modern biogeography