Indonesian Seas Research Articles

EDNA metabarcoding of decapod crustaceans across Indonesian seas has implications for biodiversity conservation and fisheries sustainability

Environmental DNA (eDNA) methods are increasingly viewed as alternate or complementary approaches to conventional capture-based surveys for marine conservation and fisheries management purposes, especially at large spatial scales in mega-biodiversity regions such as Indonesia. Decapod crustacean distribution and diversity across Indonesia are still poorly known, even for economically important fisheries commodities. This study assessed coral reef associated decapod diversity and distribution by sampling 40 sites in three regions (West, Central, East), representing 17 provinces and 10 Fisheries Management Areas (FMAs) across Indonesia, with a special focus on the blue swimming crab Portunus pelagicus. DNA sequencing (Illumina iSeq100) data were analysed in mBRAVE (Multiplex Barcode Research And Visualization Environment) yielded 406 OTUs belonging to 32 families, with 47 genera and 51 species identified. The number of families identified was highest in the Central region (25), while the most genera (31) and species (36) were identified in the West region. Alpha diversity did not differ significantly between regions or provinces, while Beta diversity differed significantly between provinces but not between regions. Our results also showed 31 species are possibility native based on the distribution meanwhile 12 species do not appear to have been recorded based of SeaLifeBase or WorMS. While providing a reference for further exploration of Indonesian coastal and small island decapod biodiversity, the high proportion of unidentified taxa calls for concerted efforts to develop and maintain reference specimen and sequence repositories and expand species conservation status assessments. The economically important decapod crustaceans identified in this study included three crabs (Charybdis anisodon, Charybdis japonica, Portunus pelagicus), a freshwater prawn (Macrobrachium nipponense), a lobster (Panulirus stimpsoni) and two penaeid shrimps (Mierspenaeopsis hardwickii and Trachysalambria aspera). For most decapod taxa, observed patterns indicate management under existing provincial and/or FMA level management structures is appropriate. Furthermore, the data can inform science-based fisheries management strategies, in particular for P. pelagicus.

The Overplay Functions and Authority of The Sea Security Board (Bakamla) and The Sea and Coast Guard in Keeping Marine Security in Indonesia

Indonesia is a maritime country with a wide ocean. Geopolitically, Indonesia’s position is an international shipping lane. Therefore, it is necessary to have an institution that has the duty and authority to maintain sea and coastal security and shipping safety. The formulation of the problem is how the functions and authorities of the Sea and Coast Guard (SCG) and the Maritime Security Agency (Bakamla) are in guarding Indonesian seas. The research method used a normative juridical approach with secondary data and analyzed descriptively qualitatively. There are two overlapping institutions in carrying out their duties and functions, namely SCG which is regulated in Law No. Year 2008 concerning Shipping and Bakamla which is regulated under the Law No. 32 Year 2014 concerning Marine Affairs. The government intends that maritime security in Indonesia to be handled by the military, not civilians. This can be seen that the chairman of Bakamla is held by a general from the Indonesian Navy and is responsible to the President through the Coordinating Minister for Political, Legal and Security Affairs. While in Law No. 17 Year 2008 stipulates that SCG is under the Ministry of Transportation and is responsible to the President. Bakamla is more appropriate to be used as SCG, this is based on the consideration that Indonesia is a maritime country with wide seas with all its problems such as narcotics trafficking, human trafficking, terrorism, theft of marine resources, etc., so it would be more appropriate to submit it to Bakamla as a semi-official institution. military. As a consequence of this choice, it is necessary to revise Law No. 17 Year 2008 and Law No. 32 Year 2014.

Effect of Tides on the Indonesian Seas Circulation and Their Role on the Volume, Heat and Salt Transports of the Indonesian Throughflow

AbstractThe effect of tides on the Indonesian Throughflow (ITF) is explored in a regional ocean model of South East Asia. Our model simulations, with and without tidal forcing, reveal that tides drive only a modest increase in the ITF volume, heat and salt transports toward the Indian Ocean. However, tides drive large regional changes in these transports through Lombok Strait, Ombai Strait and the Timor Sea, and regulate the partitioning of the ITF amongst them. The effect of tidal mixing on the salinity and temperature profiles within the Indonesian Seas drives a small decrease in the heat and salt transports toward the Indian Ocean in all three exit passages. In contrast, the tidal residual circulation due to the interaction between the tides and the topography and stratification (including the effects of tidal mixing on the circulation) leads to a large decrease in the transports toward the Indian Ocean through the Lombok and Ombai straits, but a large increase through the Timor Sea. Hence, the small net contribution from tides to the ITF's volume, heat and salt transports is due to a compensation between large, but opposing tidal residual transports at the combined Lombok and Ombai straits and in the Timor Sea. Our results indicate that explicit representation of tides, often missing in Earth system models, is necessary to accurately capture the ITF's pathway and so the tracer transport from the Pacific into the Indian Ocean.

Sea Surface Temperature and Salinity in Lombok Strait Reconstructed From Coral Sr/Ca and δ18O, 1962–2012

Coral geochemical tracers have been used in studies of the paleoclimatology and paleoceanography of the tropics and subtropics. We measured Sr/Ca and oxygen isotope ratios (δ18O) in a coral sample collected from the southern part of Lombok Strait, a significant outlet of the Indonesian Throughflow (ITF) to the Indian Ocean, to reconstruct the historical record of sea surface temperature (SST) and seawater δ18O. Seawater δ18O can be used to approximate sea surface salinity (SSS) because it reflects the balance of evaporation and precipitation. The resulting time series reconstructed SST and SSS, covering the period 1962–2012, shows no clear trend of global warming, although the record includes a large cooling event (~4°C) during 1996–1997. Although neither SST nor SSS shows a systematic relationship with El Niño–Southern Oscillation and Indian Ocean Dipole (IOD), weak but significant correlations are found partly. In addition, the coral data show signals of major IOD and El Niño events in 1994 and 1997, respectively, although climatic trends recorded in the coral are not consistent with those found along the Java-Sumatra coast. To evaluate other influences on the ITF in Lombok Strait, we compared our coral record with coral records from sites in the Java Sea, the southern part of Makassar Strait, and Ombai Strait. During the northwest monsoon (December–January–February), variations in SST and SSS at Lombok Strait site are similar to those at the Java Sea and southern Makassar sites for the period 1962–1995, which suggests that low-salinity water from the Java Sea is carried at least to the southern part of Makassar Strait where it suppresses the ITF upstream from Lombok Strait. However, the SST and SSS records differ at the three sites during the southeast monsoon (June–July–August), indicating that surface conditions in Lombok Strait vary separately from those in the Java Sea. In the longer term, although global warming has been widely identified in the Indonesian Seas, the coral record shows no clear warming trend in the southern part of Lombok Strait, where fluctuations in the ITF may be modulating the distribution of heat in the surface waters of the western Pacific and eastern Indian Ocean.

Banana blossom addition to increase food fiber in tuna (Thunnus sp.) floss product as functional food for degenerative disease’s patient

Tuna (Thunnus sp.) is a high-economic fish that is most sought after in the Indonesian seas. Tuna has good nutrition for the human body, content such as high protein, vitamin and mineral content, and has a delicious taste, so this fish can be diversified. One of the products is fish floss that can be used as functional food. This study aims to determine: (1) determine effect of banana blossom addition in fish floss to organoleptic parameter (2) determine effect of banana blossom addition in fish floss to peroxide value and water content. The method used in this study is an experimental method with an experimental design in the form of a simple Completely Randomized Design (CRD). The independent variables in this study were the concentration of banana blossom 30%, 50%, and 70% while the dependent variables were organoleptic, water content and peroxide value. The best fortification of banana blossom is 70% with organoleptic score of appearance 5.178; scent 4.922; texture 5.078; and taste 4.944. The peroxide value in the tuna floss product with 70% banana blossom concentration is 0.578 meq/kg and water content 13.33%.

A deep Tasman outflow of Pacific waters during the last glacial period

The interoceanic exchange of water masses is modulated by flow through key oceanic choke points in the Drake Passage, the Indonesian Seas, south of Africa, and south of Tasmania. Here, we use the neodymium isotope signature (εNd) of cold-water coral skeletons from intermediate depths (1460‒1689 m) to trace circulation changes south of Tasmania during the last glacial period. The key feature of our dataset is a long-term trend towards radiogenic εNd values of ~−4.6 during the Last Glacial Maximum and Heinrich Stadial 1, which are clearly distinct from contemporaneous Southern Ocean εNd of ~−7. When combined with previously published radiocarbon data from the same corals, our results indicate that a unique radiogenic and young water mass was present during this time. This scenario can be explained by a more vigorous Pacific overturning circulation that supported a deeper outflow of Pacific waters, including North Pacific Intermediate Water, through the Tasman Sea.

MARINE DEFENSE STRATEGY WITH MILITARY BASE DEVELOPMENT ON THE OUTSIDE ISLAND AS A LEADING DEFENSE AND DEFENSE MOBILITY

The construction of military bases on small islands is useful for providing mobility access to patrol boats to obtain fuel supplies or logistics. Can also provide assistance in the pursuit of foreign ships that enter Indonesian seas without permission, where the base already has a fleet ready with fast warships. The Military Base will greatly assist the mobility of the Navy in maintaining the Sovereignty of the Unitary State of the Republic of Indonesia. Evidence of the lack of Indonesian Marine Defense has made countries bordering Indonesia to make their own claims to maritime boundaries, especially in the North Natuna Sea. Two Vietnamese government surveillance vessels reportedly hit the hull of the Indonesian Navy ship KRI Tjiptadi-381 in the North Natuna Sea. Apart from claims and theft of natural resources in the Indonesian seas, currently there is also a heated issue between China and Australia, due to the US-UK-Australia cooperation called AUKUS. The Base Duties said that Lantamal's main tasks were to provide combat support, logistical support, administrative support and special support for elements of the Navy (Ships, Pesud and Marines), carry out operations and empower facilities and infrastructure owned by the base itself and related agencies. in its territory. This support capability is commonly known as the '5R' function, namely Rebase, Replenishment, Repair, Rest and Recreation. Base development on the outer islands is a form of defense and proof to countries bordering Indonesia, that the Republic of Indonesia has the power to deal with forces power that wants to threaten or claim the sovereignty of the Unitary State of the Republic of Indonesia. The construction of the base is one that supports the development of defense, the construction of bases on small islands located in the outermost parts can be used as military bases that are useful as front-line defense and also access to defense mobility, as well as carrying out the main tasks and functions of the base.

STRATEGY OF INDONESIA MARITIME DEFENSE IN THE MIDDLE OF ASIA PACIFIC CONFLICT POTENTIAL IMPLICATION OF AUKUS (AUSTRALIA, UNITED KINGDOM, AND UNITED STATES OF AMERICA) VS PEOPLE'S REPUBLIC OF CHINA

Indonesia is a country located in the Asia Pacific Region which geography located in Southeast Asia and bordering direct with People's Republic of China and Australia. With position geographical this , defense strategy Indonesian seas , namely the World Maritime Axis, must noticed return see that People's Republic of China has To do initiation in reach his ambition To use reach hegemony in the Asia Pacific Region through claim nine dash line until formation Belt Road Initiative (BRI) with use silk road. In response Thing here , United States of America with Australia and England then shape alliance defense and security with ensure security of the Asia Pacific Region which then increase tendency conflict in the region. For see defense strategy sea , research this use maritime strategy theory and theory strength sea for see Indonesian capabilities . Study this use method qualitative in composing research . Result of study this namely Indonesia must consider return of the World Maritime Axis as a defense strategy sea see that development territorial water activities in the Asia Pacific Region increase accompanied with tendency increasing conflict _ tall Among People's Republic of China and AUKUS.

Low genetic diversity and a mixing population of the reef Manta ray (Mobula alfredi, Krefft 1868) between three populations across Indonesian seas revealed by Mitochondrial DNA

Mobula alfredi is a critically endangered species of the Mobulidae family that can be found in the subtropics, including Indonesia. However, population connectedness, which is critical for managing and conserving populations, was previously unknown. Based on 614-bp of cytochrome oxidase 1 (COI) mtDNA, this study looked into the genetic structure and genetic diversity of M. alfredi between three major populations in Indonesia (Raja Ampat, Komodo Island, and Nusa Penida). Between April and December 2016, 72 tissue samples were collected using the biopsy during expedition. Komodo Island has the largest haplotype diversity and nucleotide diversity, while Raja Ampat and Nusa Penida had the lowest. Low and non-significant genetic differences were discovered between groups. The genetic variation values from the entire population revealed a greater variety within the population. Individuals of M. alfredi from three populations were mixed over Indonesian seas, as shown by the phylogenetic reconstruction and haplotype network, which was divided into two groups. M. alfredi is vulnerable to environmental change because of its low genetic diversity.

Tsunami Early Warning System Based on Maritime Wireless Communication

Tsunami buoy, linked to satellite, is commonly used as a tsunami early warning system but has been discovered to have several drawbacks such as the need for approximately 5 minutes to issue an early warning for a tsunami after detecting the initial wave as well as its fragility. It was also reported that the twenty-two buoys placed in the Indonesian seas from 2012 to 2018 were damaged and missing. Therefore, this study proposes a new method for tsunami early warning by integrating ship-to-ship maritime wireless communication. It is important to note that vessels or fishing boats with over 30 GT have the ability to travel more than 100 nmi (approximately 180 km) from the shoreline and can be equipped with point-to-multipoint VHF radio communication. Meanwhile, smaller boats on the fishing ground located approximately 2-5 km from the shore can use a WiFi network to communicate like a wireless mesh while the existing terrestrial network can be used for the ship-to-shore communication between boats and land stations. This system is expected to provide significant benefits for a fishing town such as Pangandaran, West Java, Indonesia which is directly facing Java Megathrust in the Indian Ocean. Therefore, a tsunami numerical simulation was conducted in this study using Shallow Water Equation which involved a hypothetical tsunami simulated from the possible fault source which is approximately 250 km from the source. Moreover, the vessel’s location was assumed to be in line with the fishing ground while the arrival time of the tsunami was estimated from the model to be 22.5 minutes and compared to the relay time of the proposed system which was approximately 5.4 seconds. This is faster in terms of delay than the existing system which relays information through satellite at approximately 5 minutes in an ideal condition and also has the ability to reduce the need for tsunami buoys.

Seasonal and Interannual Variability of Tidal Mixing Signatures in Indonesian Seas from High-Resolution Sea Surface Temperature

With their complex narrow passages and vigorous mixing, the Indonesian seas provide the only low-latitude pathway between the Pacific and Indian Oceans and thus play an essential role in regulating Pacific-Indian Ocean exchange, regional air-sea interaction, and ultimately, global climate phenomena. While previous investigations using remote sensing and numerical simulations strongly suggest that this mixing is tidally driven, the impacts of monsoon and El Niño Southern Oscillation (ENSO) on tidal mixing in the Indonesian seas must play an important role. Here we use high-resolution sea surface temperature from June 2002 to June 2021 to reveal monsoon and ENSO modulations of mixing. The largest spring-neap (fortnightly) signals are found to be localized in the narrow passages/straits and sills, with more vigorous tidal mixing during the southeast (boreal summer) monsoon and El Niño than that during the northwest (boreal winter monsoon) and La Niña. Therefore, tidal mixing, which necessarily responds to seasonal and interannual changes in stratification, must also play a feedback role in regulating seasonal and interannual variability of water mass transformations and Indonesian throughflow. The findings have implications for longer-term variations and changes of Pacific–Indian ocean water mass transformation, circulation, and climate.

IMPACT OF THE PANDEMIC COVID-19 TO THE INDONESIA SEAS

This paper presents the effect of the COVID-19 pandemic on the Indonesian seas from April to October 2020. Data were mainly obtained through literature studies focusing on coastal and ecosystem services, noise observation in the ocean, and in-situ data for atmospheric conditions. The results of this study found that the pandemic has given the oceans and ecosystems time to recover from anthropogenic stresses even though the tourism and fisheries sectors have experienced strong economic shocks. A decrease in the amount of pollution in several major cities in Indonesia was also found during the pandemic period.

Description and variation of ocean wave energy in Indonesian seas and adjacent waters

Results from the WAVEWATCH III simulation by the Geospatial Information Agency of Indonesia are used to describe the characteristic and variation of wind-driven waves and its energy throughout Indonesian seas and adjacent waters for 25 years (1991–2015). The simulation results are compared with buoys and Topex/Poseidon satellite observation to test the model reliability on the specific sites and regional scale. The annual average of Significant Wave Height (SWH) and its energy are presented along with monthly average of wind speed, SWH, and wave energy to describe the monthly variation across the year. In addition, the extreme environment analysis is presented through the percentile statistics of SWH and wave energy. In order to determine the suitable sites for wave energy converter installation, an overview using the index of Coefficient of Variance, Monthly Variability Index, Optimum Hotspot Identifier, and Wave Development Index is employed. Subsequently, the power rose and SWH state of the wave energy from 20 different sites representing the Indonesian seas and adjacent waters are analyzed. The study aims to illustrate the wave climate and its energy potential using the long-term open access data set available within the scope of Indonesian seas and adjacent waters.

Hubungan Strong Madden-Jullian Oscillation (MJO) Terhadap Kecepatan Angin dan Suhu Permukaan Laut (SPL) di Perairan Indonesia

Madden–Julian Oscillation (MJO) is a large-scale ocean-atmosphere phenomenon that occurs due to strong atmospheric circulation patterns and convection from Indonesian Seas then moves eastward (Pacific Ocean) with an average speed of 5 m/s. MJO is categorized into strong MJO and weak MJO whose occurrences can be identified by Outgoing Longwave Radiation (OLR). Strong MJO also has a relationship with wind and Sea Surface Temperature (SST), so that MJO events affect wind and SST. Studies on strong MJO have been conducted but in a short period, narrow research area, and only one related variable, namely the relation between MJO and precipitation The purpose of this study is understanding the relation between MJO with wind speed and SST in Indonesian Seas for the period 2003 - 2020. The data used are carried out using remote sensing technology. The research data was conducted using filtered, then analyzed by the Hovmöller diagram, and finally analyzed by correlation analysisThe research area, namely the Indonesian Seas, consists of regions A (Western Sea of Sumatera), region B (North Java Sea), region C (Southern Sea of Java), region D (Sulawesi Sea), region E (Banda Sea), region F (Aru Sea), and region G (North Papua Sea). The results of the study show that there is a relationship between OLR, wind speed, and SST where the relation between OLR and wind speed gets mostly fluctuating values, where there are negative values as well as positive values, and the relation between OLR and SST is inversely proportional.

Hydrodynamic Conditions of the Banda and Northern Arafura Seas in the Northwest Monsoon (Februay2014)

The physical and hydrodynamic conditions in the Banda and Northern Arafura Seas (BAS) during northwest monsoon (February 2014) were investigated using a three-dimensional baroclinic nonlinear numerical model—the Hamburg Shelf Ocean Model (HAMSOM). This study found that northwesterly winds induced eastward surface currents that transported relatively fresh water from the Flores Sea to the Arafura Sea via the Banda Sea. It was also found that the westerly surface currents carried relatively cold water induced by upwelling along the northern coast of the Lesser Sunda Islands. Furthermore, the simulation results revealed that relatively saline surface water from the Indian Ocean intruding through the Ombai Strait and Timor Passage contributed to the surface water of the Eastern Banda Sea and Aru Basin being more saline than the surrounding water. Part of the surface water sank as a result of downwelling in the Arafura Sea. The BAS had higher salinity than the Makassar Strait at a depth of 75 –300m. The simulation results suggested that the higher salinity was due to the influence of the South Pacific Subtropical Water (SPSW) that entered the Indonesian Seas primarily through the Halmahera Sea.

Spatial distribution of turbulent diapycnal mixing along the Mindanao current inferred from rapid-sampling Argo floats

The Mindanao Current (MC) bridges the North Pacific low-latitude western boundary current system region and the Indonesian Seas by supplying the North Pacific waters to the Indonesian Throughflow. Although the previous study speculated that the diapycnal mixing along the MC might be strong on the basis of the water mass analysis of the gridded climatologic dataset, the real spatial distribution of diapycnal mixing along the MC has remained to be clarified. We tackle this question here by applying a finescale parameterization to temperature and salinity profiles obtained using two rapid-sampling profiling Argo floats that drifted along the MC. The western boundary (WB) region close to the Mindanao Islands and the Sangihe Strait are the two mixing hotspots along the MC, with energy dissipation rate ε and diapycnal diffusivity Kρ enhanced up to ~ 10–6 W kg−1 and ~ 10–3 m2 s−1, respectively. Except for the above two mixing hotspots, the turbulent mixing along the MC is mostly weak, with ε and Kρ to be 10–11–10–9 W kg−1 and 10–6–10–5 m2 s−1, respectively. Strong mixing in the Sangihe Strait can be basically attributed to the existence of internal tides, whereas strong mixing in the WB region suggests the existence of internal lee waves. We also find that water mass transformation along the MC mainly occurs in the Sangihe Strait where the water masses are subjected to strong turbulent mixing during a long residence time.

Penegakan Hukum Lingkungan Atas Pembuangan Limbah Plastik Di Indonesia

Indonesia is the second largest contributor to plastic waste after China. It was found, as much as 187.2 tons of garbage pooled in Indonesian seas. Plastic waste in the oceans threatens marine biota ecosystems and human life. Prediction that in the coming year, more human food sources will be contributed from the sea. This problem needs to be the main point of the state in terms of preventing environmental damage. The State of Indonesia has regulated the oldest environment in the PPLH Law. In preventing these problems, it is necessary to carry out surveillance efforts by law enforcement officers in the community. However, supervision efforts in the field as a preventive measure are not carried out optimally, the sanctions applied are not firm, making the community and business actors not heed the legal rules that have been made. Enforcement of environmental law is carried out with three legal instruments, namely administrative sanctions, civil matters and criminal matters. Reflecting on developed countries, such as the neighboring country of Singapore, Indonesia should apply the rule of law strictly, considering that efforts to protect the environment are fundamental to making the country in it a comfortable place. In protecting the environment of the State of Indonesia, the government should act decisively in enforcing the law and implementing new legal rules, namely in the form of fines that can be applied to the community and should be the main priority of the state to keep the country free from plastic waste in the oceans.

Seasonal Variability of The Mixed Layer Depth in The Sulawesi Sea

The Sulawesi Sea is a semi-enclosed basin located in the Indonesian Seas and considered as the one of location in the west route of Indonesian Throughflow (ITF). There is less attention on the mixed layer depth investigation in the Sulawesi Sea. Concerning that the mixed layer plays an important role in influencing the ocean in air-sea interaction and affects biological activity, the estimation of mixed layer depth (MLD) in the Sulawesi Sea is important. Seasonal variation of the mixed layer in the Sulawesi Sea between 115°-125°E and 0°-8°N is estimated by using World Ocean Atlas 2013. Forcing elements on the mixed layer in terms of surface-forced turbulent mixing from mechanical forcing of wind stress and buoyancy forcing (from heat flux as well as freshwater flux) in the Sulawesi Sea is provided by using a reanalysis dataset. The MLD is estimated directly on grid profiles with interpolated levels based on chosen density fixed criterion of 0.03 kg.m<sup>-3</sup> and temperature criterion of 0.5°C difference from the surface. The results show that mixed layer depth in the Sulawesi Sea varies both spatially and temporally. Generally, the deepest MLD was occurred during the southwest monsoon (JJA), and the lowest MLD was occurred during the first transition (MAM) and second transition monsoon (SON). Strengthening and weakening MLD are influenced by mechanical forcing from wind stress and buoyancy flux. In the Sulawesi Sea, the mixed layer deepening coincides with the occurrence of a maximum in wind stress, and low buoyancy flux at the surface. This condition is the opposite when mixed layer shallowing occurs.

The Movement of Plastic Marine Debris in Indonesian Seas using A Trajectory Model

There are many studies on ocean currents transporting plastic marine debris using hydrodynamic models and trajectories that have been carried out. However, it is still constrained to be applied in Indonesian waters. Therefore, this research aims to obtain the movement patterns of plastic marine debris, influenced by the dynamics of currents in Indonesian waters using hydrodynamic and trajectory models. The methodology used in this research is to use the HAMburg Shelf Ocean Model (HAMSOM) numerical model and the trajectory model. Plastic marine debris is assumed to be conservative particles at sea level with a macro size (2.5 cm-1 m). The particles are released in 6 coastal cities (Manado, Balikpapan, Makassar, DKI Jakarta, Semarang, and Denpasar) at the month and stop at the end month (January, April, July, October). The results showed that particles originating from 6 coastal cities moved along the current to the surrounding areas only, across islands within the Indonesian territory, and even left Indonesian territory.

Modeling small-pelagic fish biomass in the Indonesian seas: climate variability and climate change impacts

The present study uses the Community Earth System Model, version 1– Biogeochemistry [CESM1(BGC)] to examine the influence of climate variability and climate change on small pelagic fish biomass in the Indonesian seas. The fish biomass was calculated based on a fish production model according to primary production and energy transfer at the tropic level. The primary production data were obtained from results of CESM1(BGC) model from 1850 to 2015. Empirical orthogonal function (EOF) analysis of the calculated fish biomass identifies three regions in the Indonesian seas that are associated with coastal upwelling. These regions are located in (1) southern coast of Central Java Province until west-coast of West Sumatra Province, (2) southern coast of Central Java Province until the southern coast of Bali Province, and (3) Banda-Arafura Seas. Fish production variability in these regions exhibits semi-annual, annual, and IOD-ENSO related signals. Climate change impact for RCP 4.5 scenario produces ‘fish stock increase status’ in 2025 for the three regions, while the ‘fish stock current status’ will reoccur in 2050, except for the western part of Sumatra (part of region-1) which alters to ‘fish stock decrease status’.