papillare JournalPLVol4No1 O. JournalPLVol4No1 O

44 Pesisir Lautan Volume 4, No.1, 2001 Mapping of species distributions The specimen-based database was used to pre- pare a distribution list for each species in ASCII format, including site coordinates for each speci- men record. These lists were used to plot the distri- bution records for each species in Indonesia, using a MAPINFO Geographic Information System package for WINDOWS. Similarity between regions Comparisons between regions were based on Jaccard’s similarity coefficient. Similarity = aa+b+c, using the number of species in common, where a = number of species shared by two regions being com- pared, b = number of species in sample 1 and not in sample 2, and c = number of species in sample 2 not in sample 1. Note that a+b+c = the total number of species in the two areas. This measure was chosen for simplicity and because it is not sen- sitive to the presence of species in a wider region that are not present in the two areas being com- pared, that is joint absences Batagelj and Bren, 1995. Sampling and database protocol At the 146 survey sites, sampling followed a standard protocol, using SCUBA, or occasionally snorkelling or reef-walking on shallow sites. The presence of Acropora species was recorded, begin- ning from the greatest depth at which they could be located usually 25-28 m and continuing up- wards to shallow water, over a horizontal distance of 100-400 m. Sites were assigned to the following overall reef types: fringing, coral cay, sand cay, sub- merged reef, shoal, patch reef, rocky reef, volcanic ash slope, deep reef flat, barrier reef, and pinnacles Tomascik, 1997. Within each reef type, the par- ticular habitat sampled was categorised according to the following categories: 1 recent volcanic sur- face, 2 reef slope and associated flat, 3 reef wall and associated flat, 4 lagoons, sheltered inlets or submerged reefs Wallace and Wolstenholme, 1998. Habitat features and dominant benthic groups were noted for each site. Small samples of each species encountered were taken for verification and more colonies were sampled for taxonomic description when unusual forms were encountered. Most specimens were photographed in situ before collection. An initial identification, including colour of the colony, unusual size or colony shape, and depth were recorded. A numbered plastic label was attached to each specimen as it was collected. After sampling, specimens were bleached in 3 NaOCl, rinsed in fresh water, and dried. Specimen identifi- cations were later verified by microscopic examina- tion in the laboratory. A complete set of voucher specimens for the sites is stored at the Museum of Tropical Queensland in Townsville, Australia, and registered on a database that includes coordinate data for GIS mapping. Additional sets of specimens were deposited with the Indonesian Institute of Science LIPI, LIPI Research and Development Centre for Oceanology PPPO at Ancol, Java Sulawesi Sea and Bay of Tomini collection; LIPI PPPO at Ambon, Moluku Province Banda Sea collection; and De- partment of Marine Science, Bung Hatta Univer- sity Padang, Sumatra Sumatra collection. Table 3. Number of Acropora species in each distribution category for each region within Indonesia. Two new species included in this distribution category. Distribution Sumatra Indonesia Indonesia Sulawesi Bay of Banda Category Central South Sea Tomini Sea Indian Ocean 2 1 2 1 1 Shared IND Indo-Pacific 36 53 59 59 58 58 Indonesian I-P Pacific Ocean 1 6 4 10 13 4 Shared PAC Indonesia Only ARC 1 1 2 6 2 Total number of species 40 59 65 73 78 65