Repeated physical disturbances and the stability of sub-tropical coral communities in Hong Kong, China

1. This paper reports on the dynamics of the coral community structure at A Ma Wan (AMW) and A Ye Wan (AYW) in Tung Ping Chan, Hong Kong, focusing on data collected before and after the Summer typhoon seasons in 1997 to 1999. This period (1999) experienced the highest frequency of severe tropical cyclones to hit Hong Kong with one cyclone being the strongest to hit in the last 23 years (1984 to 2006). 2. This is part of a long-term monitoring programme Of subtropical coral communities that has been set Lip in AMW since May 1997 and AYW since May 1998 with nine fixed position 40 in long transects and 0.5 m x 0.5 m permanent quadrats laid at 5m intervals along each transect. A total of 45 scleractinian coral species from 21 genera (12 families) was recorded, with 40 species in AMW and 32 species in AYW recorded at the beginning of the study. 3. Multidimensional scaling ordinations showed distinct spatial variations in the coral communities Within and between sites. These variations were probably a result of the differential effects of the repeated cyclone impacts on the communities. Cyphastrea serailia, Goniopora lobata, Montipora peltforms and Pavona decussata were the dominant species most strongly affected by cyclone impacts at AMW, experiencing a 6.2-16.21% loss of mean area cover during the Study period. Some dominant species (e.g. P. decussata) in AYW also experienced a 6.5-14.3% loss of mean area cover within the same period. 4. Overall, these coral community Structures appeared relatively stable and resistant to repeated physical disturbances. However, they may have low resilience towards more severe disturbances in the future. Preserving the resilience of coral communities/species in Tung Ping Chan should be one of the main goals of coral strategies for the island. Copyright (C) 2009 John Wiley & Sons, Ltd.