Monitoring of South Sinai coral reefs: influence of natural and anthropogenic factors

1. To monitor any impacts to coralreefs related to the exponential growth of tourism in the South Sinai region of the Egyptian Red Sea, nine stations were established at key reef sites over 2002–2003. At each station coralcover was determined using a video survey method at depths of 3, 7 and 16 m, and fish abundance by underwater visual census at depths of 3 and 10 m. 2. Mean total coralcover (hard plus soft) ranged from 58% to 23% at 3 m, 50% to 14% at 7 m, and 52% to 13% at 16 m, and hard coralcover from 37.5% to 15.7% at 3 m, 32.8% to 7.0% at 7 m, and 17.8% to 2.2% at 16 m. Analyses confirmed differences in coralassemblage related to depth and wave exposure. 3. Fish abundances and assemblages also varied with depth and proximity of deep water. Also the one site subject to fishing had lower abundances of some commercial fishfamilies and greater abundances of some herbivores. 4. Transects subject to greater tourist use did not segregate from those subject to less tourist use, despite evidence from other work of an effect from visitor damage to coralsat some sites. This may be because visitors were more attracted to sites that had higher coralcover. 5. Comparison of the present data with that from past studies is difficult because of the differences in sites and method employed, but several observations suggest a moderate decline in coralcover during recent decades. Such a decline would be compatible with the recorded impact of an outbreak of crown-of- thorns starfish, Acanthasterplanci, as well as with other evidence of accumulating damage by visitors. 6. Further monitoring using the same stations and consistent protocols is urgently required. Copyright © 2008 John Wiley & Sons, Ltd.