Madduppa HH, Subhan B, Suparyani E, Siregar AM, Arafat D, Tarigan SA, Alimuddin, Khairudi D, Rahmawati F, Bramandito A. 2013. Dynamics of fish diversity across an environmental gradient in the Seribu Islands reefs off . The reefs of Seribu Islands have been affected by multitude of anthropogenic pressures. However, the biodiversity of reef fishes across the archipelago linked to environmental condition is poorly known. This study aimed to investigate the biodiversity and the trophic level of fish communities across the archipelago. The study on reef fish communities was conducted on 33 reef sites associated with islands or shoal randomly chosen from each zone along environmental gradients from the inshore water nearest of Jakarta Bay to the offshore water of the outer islands. The study sites represented each sub-districts within the archipelago, namely Pari, Tidung, Panggang, Kelapa, and Harapan. A total of 46,263 individual fishes were counted, belonging to 216 species and 29 families. The multivariate analysis of fish abundance using the Bray Curtis similarity index and non-metric multidimensional scaling (MDS) clearly showed the clustering of sub-districts, near and far from Jakarta Bay. The results showed that the sub-districts can be clustered into three groups. Group one consists of one sub-district (Pari) located in the southern part of the Seribu Islands near Jakarta Bay. Group two consists of three subdistricts (Tidung, Panggang, Kelapa) located in mid of the archipelago. The third group consists of one sub-district (Harapan) located in the northern part of the Seribu Islands. Based on species richness and fish diversity indices, the sub-districts can be clustered into two groups (1 = Pari and Tidung, 2 = Panggang Kelapa, Harapan). However, levels of similarities among sub-districts varied. The fish community in sub-district of Pari was dominated by carnivorous, omnivorous and herbivorous fishes, while those in the rest of subdistricts were dominated by omnivorous and carnivorous fishes. The present study results showed that the biodiversity of reef fishes across the Seribu Islands seemed to be linked to the environmental conditions.

Bramandito A, Subhan B, Prartono T, Anggraini NP, Januar HI, Madduppa HH. 2018. Genetic diversity and population structure of Siganus fuscescens across urban reefs of Seribu Islands, Northern of Jakarta, Indonesia. Biodiversitas 19: 1993-2002. Jakarta bay and Seribu Islands reefs have been affected by anthropogenic activities which causing them degraded and low quality of the ecosystem. However, lack of study has been conducted to investigate the effect on reef fish population due to change in ecosystem quality. Therefore, this study was undertaken to analyze genetic diversity and population structure of Siganus fuscescens population against heavy metals (Pb, Cd, and Cu) concentration across Jakarta Bay and Seribu Islands environmental gradient. Genetic diversity and structuring of S. fuscescens populations were determined using partial sequences of the mitochondrial cytochrome C oxidase I. Monitoring of heavy metal was measured by Atomic Absorption Spectroscopy (AAS) shows highest concentration of heavy metal (Pb, Cd, and Cu) was observed in the southern of Seribu Islands, closest to Jakarta. However, the diversity of haplotype obtained from each location indicates a varied range between 0,1429 (Pramuka Island, located in the center) and 0,75 (Untung Jawa Island, located in the south). Linear regression test reveals that Cu elements had a moderate effect (R2 adjusted = 0.665) to the nucleotide diversity of the fish. The study shows some populations of S. fuscescens have been affected by heavy metal and could be an alarm to manage this artisanal targeted fish in the Seribu Islands.

Patterns of community structure within coral reefs ecosystems are strongly influenced by a catastrophe such as a tsunami. Sumur is one of the coastal regions affected the most by the Banten Tsunami in December 2018. This research aims to predict coral reef ecosystem conditions after a tsunami based on the reef fish community structure and benthic coverage in the previous month. The research was conducted on every island around Sumur coastal region. Reef fish specimens were sampled using underwater visual census, and benthic coverage was taken with quadrats for Coral Point Count Estimation (CPCe). Overall coral condition assessed by conservation value determined through coral morphology. The highest coral coverage was found in Sumur, Southwest Oar, and North Badul. Nearly all sites have a high diversity reef fish community, with the highest abundance and species richness found in West Umang and North Badul. Badul island, Mangir island, and Cigorondong were categorized as the locations with coral reef ecosystems with the highest stress-tolerators. Most areas with this high stress-tolerator are predominated by coral massive and sub-massive and have higher endurance than other sites. Post-catastrophe, reef fishes will shift to the sites where most coral reef-building has survived, especially reef fishes with territorial behaviour.

Production of bioactive compounds from marine benthic organisms is suggested to relate ecologically with environment. However, anthropogenic pressures cause a considerable damage to coral reefs environment. This research aimed to define the pattern sponges biopotential values at the increasing of anthropogenic pressures to coral reef environment. Three representative sponges were selected (Theonella sp., Hyrtios sp., and Niphates sp.) and study had been conducted in Hoga Island, Indonesia, to define the relationship between seawater variables (DO, pH, phosphate, and ammonia ions), sponges spatial competition, and their bioactivity level (Brine Shrimp Lethality Test). The study showed anthropogenic pressures affect the reef environment, as abiotic cover was increased and eutrophication was detected at the site closer to the run-off domesticated area. Statistical multivariate analyses revealed sponges spatial competition was significantly different (P < 0.05) between groups of high, moderate, and low bioactivity level. Abiotic cover was detected as the major factor (36.19%) contributed to the differences and also the most discriminant factor distinguishing sponges spatial competition in the groups of bioactivity level (93.91%). These results showed the increasing anthropogenic pressures may result in a higher abiotic area and may directly be a consequence to the lower production of bioactive compounds in sponges.

Fish serum albumin (FSA) is an aquatic resource that has potential to be developed as nutraceutical. Therefore, research was undertaken to assess albumin levels in the aqueous extract of muscle tissue of several Perciformes commonly available at a local fish market in Indonesia. Three random replicates for each of 17 Perciformes species were collected and assessed for their FSA content by application of a reversed-phase (C4) HPLC analytical method. Results of these analyses showed that the albumin concentration of the extracts was in the range 3.49-12.61 g/L, and that they varied significantly (P < 0.05) between species and families. This finding may mean that FSA levels are species and family dependent, something that could be investigated in future studies. As fishes from the family Scrombidae showed the highest concentration (12.61 g/L) of FSA, they would likely have the most value as a source for production of albumin-based nutritional and/or clinical products.