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441.
- 1. Marine protected areas (MPAs) are being used increasingly to manage and protect marine resources. Most studies of MPAs have focused on fish. In this study, the influence of MPA protection on coral reef benthic organisms on the Great Barrier Reef (GBR) was investigated. In addition, the interaction between protection and natural disturbance history was examined.
- 2. Differences in benthic cover inside and outside MPAs were assessed at 15 pairs of Protected and General Use reefs on the GBR using annual monitoring data from the Australian Institute of Marine Science's Long‐Term Monitoring Programme (LTMP). At each reef, benthic cover was determined using a benthic video survey at three sites, with each site consisting of five 50 m transect lines separated by at least 250 m running parallel to the reef crest at 6–9 m depth.
- 3. Benthic cover was related to both protection status and disturbance history, but natural perturbations exerted a stronger influence on benthic cover than did protection status. The influence of natural perturbation was most noticeable for hard coral.
- 4. Most reefs where no natural disturbance events had occurred (‘undisturbed reefs’) had higher hard coral cover and lower soft coral cover than General Use reefs. While the high levels of hard coral on Protected reefs may be a result of protection status, it might also have resulted from selection bias that occurred during the initial zoning of the Great Barrier Reef Marine Park (i.e. managers may have given protection status to reefs with high coral cover).
- 5. These results are likely influenced by the relatively low intensity of human use, both on the Great Barrier Reef in general and at the particular monitoring sites studied. Over time, as local populations and tourism increase, the effect of protection may become more evident at LTMP sites. Copyright © 2009 John Wiley & Sons, Ltd.