title: Community-level destruction of hard corals by the sea urchin Diadema setosum.
abstract: Sea urchins are common herbivores and bioeroders of coral ecosystems, but rarely have they been reported as corallivores. We determined the spatial pattern of hard coral damage due to corallivory and bioerosion by the sea urchin Diadema setosum Leske in Hong Kong waters. Coral damage was common at the northeastern sites, with 23.7 - 90.3% colonies being either collapsed or severely damaged with >25% tissue loss. Many genera of corals were impacted by the sea urchin but the damage was most obvious for the structure forming genus Platygyra. The percentage of severely damaged and collapsed coral had significant positive correlation with the abundance of D. setosum, which ranged from 0.01 to 5.2 individuals per coral head or 0.1 - 21.1 individuals m(-2) across the study sites. Remedial management actions such as sea urchin removal are urgently needed to save these fringing coral communities.
authors.affiliation: Department of Biology, Hong Kong Baptist University, Hong Kong. Electronic address: qiujw@hkbu.edu.hk.
authors.forename: Jian-Wen
authors.initials: JW
authors.lastname: Qiu
authors.affiliation: Agriculture, Fisheries and Conservation Department, Hong Kong SAR Government, Hong Kong.
authors.forename: Dickey C C
authors.initials: DC
authors.lastname: Lau
authors.affiliation: Agriculture, Fisheries and Conservation Department, Hong Kong SAR Government, Hong Kong.
authors.forename: Chi-chiu
authors.initials: CC
authors.lastname: Cheang
authors.affiliation: Agriculture, Fisheries and Conservation Department, Hong Kong SAR Government, Hong Kong. Electronic address: wk_chow@afcd.gov.hk.
authors.forename: Wing-kuen
authors.initials: WK
authors.lastname: Chow
mesh_terms: D000818:Animals; D037421:Anthozoa; D017753:Ecosystem; D006723:Hong Kong; D012617:Sea Urchins
keywords: Bioerosion; Coral; Diadema; Platygyra; Predation; Sea urchin