(Editor’s note: Conservancy Senior Marine Scientist Alison Green is on an expedition to the Raja Ampat islands in Indonesia — amidst some of the most spectacular and biodiverse coral reef ecosystems in the world. Catch up on all her posts from the expedition.)
We are in Southeast Misool, which boasts some of the most biologically diverse coral reefs in Raja Ampat…and therefore the world.
But just why is this region so spectacularly diverse?
The diversity is created by the multiple and complex habitats and oceanographic conditions that occur in the area. Currents, exposure to or shelter from winds and waves, water depth and distance to deep oceanic water — all these influence the coral communities that form in the area. According to Sangeeta Mangubhai, who manages the Conservancy’s conservation program in Raja Ampat, Southeast Misool is a perfect example of corals responding to all these environmental factors.
During this expedition, we have dived on reefs that are covered in foliose corals (shaped like cabbages!) and reefs covered in thickets or forests of branching corals. We have dived on reefs that at first glance look dead, but on closer second inspection are covered in corals that form flat sheets that encrust the reef.
One of Sangeeta’s favorite coral dives was deep inside the karst limestone chain of islands in the north of the protected area. Sheltered from all winds and waves, and sitting above a thick layer of calcareous ooze (very fine sediment that explodes into cloudy mist when disturbed), the corals were very strange. Branching corals were very fine, weird and contorted.
What was amazing is the diversity of corals that were found in these sheltered environments, and how well they have thrived and formed flourishing coral communities with diverse fish life.
Wherever there is space and suitable habitat, corals are found covering all available surfaces — in all sorts of shapes and sizes.
(Image 1: Weird and contorted coral. Credit: Sangeeta Mangubhai. Image 2: Diverse coral community with foliose corals. Credit: Andreas Muljadi.)