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.

Achantaster planci atau Crown-of-thorns starfish merupakan hewan pemangsa karang yang secara langsung dapat menyebabkan degradasi pada ekosistem terumbu karang. Penelitian ini bertujuan untuk mengetahui kelimpahan dari A. planci dan kondisi karang di Pulau Saparua. Jumlah lokasi pengamatan sebanyak lima stasiun. Penelitian ini dilaksanakan pada November 2018 di Pulau Saparua, Kabupaten Maluku Tengah, Provinsi Maluku. Pengamatan tutupan karang hidup dan kelimpahan Achantaster planci dilakukan dengan menggunakan metode Line Intercept Transect (LIT), pengamatan Acanthaster planci menggunakan metode sabuk (Belt Transect) yang mengikuti garis LIT dengan panjang 70 meter dan lebar 2 meter sehingga luasan area pengamatan sebesar 140 m2. Hasil penelitian menunjukkan kondisi tutupan karang hidup tergolong kedalam kriteria sedang hingga sangat baik (26,5%-89,54%) dan terdapat sepuluh bentuk pertumbuhan yang ditemukan pada lokasi ini. Indeks mortalitas karang tertinggi pada Stasiun (Stn) 2, daerah dimana tidak ditemukan A. planci. Keberadaan A. planci hanya ditemukan pada Stn 1, Stn 4 dan Stn 5, dengan kelimpahan A. planci tertinggi ditemukan pada Stn 1 sebanyak 0,036 ind/m2. Bentuk pertumbuhan karang Acropora mendominasi hampir pada seluruh stasiun dan A. planci ditemukan pada stasiun yang memiliki tutupan karang hidup yang didominasi oleh bentuk pertumbuhan Acropora branching dan coral branching. Korelasi baik tutupan karang dan kelimpahan A. planci maupun karang mati dan A. planci tergolong cukup dan tidak signifikan. Achantaster planci or Crown-of-thorns starfish are coral predators that can directly cause degradation of coral reef ecosystems. This study aims to determine the abundance of A. planci, live coral cover on Saparua Island. The number of observation stations was five locations. This research was conducted in November 2018 on Saparua Island, Central Maluku Regency, Maluku Province. Observations of live coral cover and Achantaster planci abundance were carried out using the Line Intercept Transect (LIT) method, Acanthaster planci observations using the Belt Transect method which followed the LIT with a length of 70 meters and a width of 2 meters so that the area of   the observation area was 140 m2. The results showed the condition of live coral cover was classified as moderate to very good criteria (26.5% -89.54%) and there were ten of coral lifeforms found at this location. The highest coral mortality index was determined in St 2 areas where A. planci was not found. The presence of A. planci was only found in St 1, St 4 and St 5, where the highest abundance of A. planci was found in St 1 by 0.036 ind / m2. Acropora coral growth forms dominate almost all stations and A. planci is found in stations that have live coral cover dominated by Acropora branching and coral branching growth forms. Correlation of both coral cover and abundance of A. planci and dead coral and A. planci is classified as sufficient and not significant.

Updated information regarding tunicates distribution and diversity in the waters around Ambon Island is scarce if any. We carried out an assessment using the underwater census approach in June 2018 to obtain the said information. Tunicates’ composition and distribution were described based on six sampling station observations. Their average density in five of six stations was less than one individual per meter square. Predominant genera observed were Didemnum and Polycarpa. Tunicates belonging to Polycarpa sp. had 12 color variations on its tunic. Those sampled in Hitu had the most variations (8 variants) compared to all the other four stations. Didemnum sp. was highly abundant in three stations (Morella, Hitu, and Larike). Those identified as Polycarpa sp. were predominant only in two stations (Mamala and Wakal). Further studies are needed to investigate the anthropogenic pressure effect on these tunicates, as they were known as biomarkers in ecotoxicological studies.

Here we present the study of meroplankton in Ambon Bay. This study aims to determine the composition and abundance of meroplankton in Ambon Bay. Sixteen stations (eight in the IAB and eight in the OAB) were sampled in March 2022. A plankton sampling was carried out using a plankton net with a mesh size of 300 microns and a diameter of 30 cm drawn at a depth of 10 meters to the surface. The study results showed that the meroplankton in Ambon Bay at the time of observation consisted of fish larvae, fish eggs, Echinodermata larvae, gastropoda larvae,cirripedia larvae, stomatopoda larvae, bracyura larvae (megalopa), bracyura larvae (zoea), nauplius crustacea, sea anemone larvae, other crustacea larvae and annelida larvae. The abundance of meroplankton in the IAB is higher than in the OAB. ANOSIM showed significant differences between IAB and OAB (p <0.05). SIMPER analysis showed that the mean dissimilarity between IAB and OAB was of 56.16%. The meroplankton group was dominated by Echinodermata larvae, which were found to dominate at all research stations, especially in the inner bay of Ambon, with the highest abundance found at station 4, which was 120.31 ind.m−3.

A study on coral reefs status was conducted on the island of Wetar, Leti, and Moa of Southwest Maluku District. Nine stations were assigned as sampling stations to analyze the coral reefs’ condition of these three islands. The Underwater Photo Transect method was applied to analyze the percentage of biotic and abiotic components of coral reef communities with Coral Point Count Excel (CPCe) software, whilst the underwater visual census for reef fish data. Coral reef health indices were determined based on benthic lifeform components and reef fish biomass. Our findings showed that the coral cover in Wetar, Moa, and Letti island consists of 124 species that belong to 44 genera and 15 families of hard coral. The condition of coral reefs was considered at category 3 due to the high percentage of coral cover that range between 20.85 – 71.55 % with an average of 42.87 %. The average biomass of target fish in the waters of Wetar, Letti, Moa, and its surrounding areas was 129.309 g/m2 or 3,694 kg/ha. The Kaiwatu site (BWI03) was recorded to have the highest biomass of 305,487 g/m2 or 8,728 kg/ha and the lowest was the Klis site ((BWI 08) with a value of 1285 g/m2 or 36,70 kg/ha. The coral reef health index values of nine study sites ranged between grade 5 and 10, of which two locations got a score of 10 (very good) categories, five locations got a good category and two locations got a low score. The overall results indicate that the coral reef is in a healthy condition, yet, the use of non-environmental friendly fishing gears partly damages coral reef beds.