Recent disturbances augment community shifts in coral assemblages in Moorea, French Polynesia |
| |
Authors: | M S Pratchett M Trapon M L Berumen and K Chong-Seng |
| |
Institution: | (1) ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD, 4814, Australia;(2) School of Marine and Tropical Biology, James Cook University, Townsville, QLD, 4814, Australia;(3) King Abdullah University of Science and Technology, Thuwal, 23955-6900, Kingdom of Saudi Arabia |
| |
Abstract: | Coral reefs are often subject to disturbances that can cause enduring changes in community structure and abundance of coral
reef organisms. In Moorea, French Polynesia, frequent disturbances between 1979 and 2003 caused marked shifts in taxonomic
composition of coral assemblages. This study explores recent changes in live cover and taxonomic structure of coral communities
on the north coast of Moorea, French Polynesia, to assess whether coral assemblages are recovering (returning to a previous
Acropora-dominated state) or continuing to move towards an alternative community structure. Coral cover declined by 29.7% between
July 2003 and March 2009, mostly due to loss of Acropora and Montipora spp. Coral mortality varied among habitats, with highest levels of coral loss on the outer reef slope (7–20 m depth). In
contrast, there was limited change in coral cover within the lagoon, and coral cover actually increased on the reef crest.
Observed changes in coral cover and composition correspond closely with the known feeding preferences and observed spatial
patterns of Acanthaster planci L., though observed coral loss also coincided with at least one episode of coral bleaching, as well as persistent populations
of the corallivorous starfish Culcita novaeguineae Muller & Troschel. While climate change poses an important and significant threat to the future structure and dynamics coral
reef communities, outbreaks of A. planci remain a significant cause of coral loss in Moorea. More importantly, these recent disturbances have followed long-term shifts
in the structure of coral assemblages, and the relative abundance of both Pocillopora and Porites continue to increase due to disproportionate losses of Acropora and Montipora. Moreover, Pocillopora and Porites dominate assemblages of juvenile corals, suggesting that there is limited potential for a return to an Acropora-dominated state, last recorded in 1979. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|