Around 77% of Indonesian islands is small islands and Indonesia known as mega biodiversity center, but coastal biodiversity of small islands was not well documented. The objective of this study is to assess coastal biodiversity in small islands and its conservation status. The study indicated that small islands provide complex biodiversity ranging from ecosystem to species. Diversity index of mangrove: 1.4-1.8, seagrass: 1.5–1.9, coral: 1.7–2.3. Ecosystem condition in urban small island was poor and in rural small island was healthy. The islands also provide fauna diversity i.e mollusc (110 species), crabs (52 species), and coral fish (261 species). Diversity of mollusc and crabs in rural island was higher than in urban island, χ2 (1) = 1.3, p< 0.001 and χ2 (1) = 4.3, p< 0.002, respectively. Diversity index of coral fish range from 2.14 to 4.27 (mean: 3.4). Most of the biodiversity located outside protected area and main threats were ecosystem degradation, pollution, overexploitation, and sedimentation. In conclusion, small islands are important coastal biodiversity spots, but it faces tremendous threats. The study recommends better management of coastal biodiversity i.e. establishing coastal protected areas in small islands, building marine corridor, and public awareness to ensure biodiversity conservation.

Study on imposex of Thais aculeata was conducted in September to October 2016 in Talake Shipyard, Ambon Bay. The aim of this study was to investigate and describe the imposex insidence in muricids T. aculeata. Level of imposex was calculated using some indices i.e. RPLI (Relative Penis Length Index), RPSI (Relative Penis Size Index) and PI (Percentage of Imposex). A total of 110 individuals T. aculeata consisted of eight size classes were found, which 39 females individuals were identified to be exposed of imposex. Females with imposex were characterized by the presence of pseudopenis in the form of a small bulge on the top right of the tentacles. Pseudopenis relatively smaller than that of male penis size i.e. 2.13 mm while male penis size was 4.95 mm. Percentage of imposex of T. aculeata was 41.05%, RPSI was 7.97; RPSI was 49.58, and sex ratio of male and female individuals was 1:6.3 The correlation between class size shell with imposex was moderate relationship (R = 0.44). Ratio between number of male individuals and female with imposex was significantly different, but ratio between normal females and females with imposex; and shell length average between normal females and females with imposex was not significantly different, respectively.

The present study reports and discusses population structure and morphometric relationships of muricid <em>Reishia bitubercularis</em> in two populations from Ambon Island, Maluku. Field sampling was conducted at two locations with typical hard substrate i.e. Ambon Bay and Central Maluku, where each location comprises three different stations. Morphometric relationships were analyzed for shell dimensions i.e., shell length (SL), shell width (SW), shell height (SH) and total weight (TW). A total of 496 individuals of <em>R. bitubercularis </em>were collected in both locations. SL ranged from 7.07 to 42.38 mm in Ambon Bay, and 12.45 to 42.69 mm in Central Maluku. The highest number of individuals in Ambon Bay and Central Maluku was in size 26-28 mm and 30-32 mm, respectively. The mean SW/SL ratio ranged from 0.67 mm to 0.73 mm. Sex ratio was significantly different from 1:1, with females outnumbered males in both locations. Morphometric relationships indicated SL grows faster than SW in both locations and faster than SH and TW in Central Maluku. While the growth rate between SL vs SH; and TW vs SL are relatively similar in Ambon Bay. Overall, both Ambon Bay and Central Maluku have a similar variation of abiotic factors which also play an important role in shell morphometrics and relative growth of muricids, especially related to the exposed area in the rocky intertidal zone where sampling was conducted.