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A planned artificial reef (AR) deployment program as part of a fisheries enhancement might be a useful tool for managers to supplement traditional ways to utilize available space and augment local productivity. Several AR deployment initiatives have been carried out globally, but they are rarely subjected to a rigorous site selection process. We created a site selection procedure in this study that includes systematic stages including exclusion mapping, underwater visual transect, benthic composition, seawater quality, and comparative visual mapping. This research focused on restoring the fishing grounds for artisanal fishermen by deploying AR along the southeast coast of India. The results of each stage in the procedure enabled us to choose suitable locations at a target depth with low wave action, no slope, and a good substrate capable of supporting an AR. Analysis of variance (ANOVA-one way) showed significant (p < 0.05) spatial variation for depth, slope, seawater current, salinity, chlorophyll-a, benthic density, and diversity. The geographical information system (GIS) based model output showed space allocation for AR deployment. The GIS methodology for site selection was developed to be easily adaptable to the demands of diverse artificial reef programs. The integrated strategy has proven to be a successful regulatory intervention for AR deployment practices in order to facilitate coastal restoration and management.

The Lombok Strait (LS), Ombai Strait (OS), and Timor Passage (TP) are three major outlets of the Indonesian Throughflow to the Indian Ocean. Here, sources and pathways of the LS, OS, and TP outflows are explored by a Lagrangian particle tracking analysis based on a ~3 km regional ocean model simulation. The Makassar Strait transport contributes to ~80%, ~75%, and ~45% of the LS, OS, and TP outflows, respectively. However, ~41% and ~19% of the TP and OS outflows stem from the Lifamatola Passage, which largely feeds the upper and intermediate layers of the outflows. The role of Karimata Strait is quite limited and restricted to the upper layer. It takes 1-2 years and 2-6 years for the Makassar Strait water to reach the OS and TP, respectively, whereas the Lifamatola Passage water passes through the OS (2-6 years) and TP (3-9 years) on a prolonged transit time. In the Banda Sea, the western boundary current is the main pathway toward the OS, while the waters to the TP tend to take a basin interior route.

Molybdenum and tungsten are redox-sensitive elements, and their stable isotope ratios have attracted attention as paleoceanographic proxies. However, our knowledge of the distribution of stable Mo and W isotopes in the modern hydrosphere remains limited. In this study, we provided the concentrations and isotope ratios of dissolved Mo and W in the oceans (the North Pacific and Indian Oceans), marginal seas (the East China Sea and Sea of Japan), and a river-estuary system in Japan (from the Uji-Yodo rivers to Osaka Bay). In the North Pacific and Indian Oceans, the W concentration was 48.2 ± 6.2 pmol/kg (ave ± 2sd, n = 109), δ186/184W was 0.52 ± 0.06 ‰, the Mo concentration was 105.1 ± 8.0 nmol/kg, and δ98/95Mo was 2.40 ± 0.06 ‰. The results indicate that W has the constant concentration and isotopic composition in the modern ocean as well as Mo. In the East China Sea and the Sea of Japan, the W concentration and δ186/184W in the upper water (< 1000 m depth) were different from those in the ocean (W = 56 ± 18 pmol/kg, δ186/184W = 0.45 ± 0.06 ‰, n = 24). However, the concentrations in deeper water were congruent with those in the oceans (W = 49.9 ± 7.6 pmol/kg, δ186/184W = 0.50 ± 0.02 ‰, n = 7). The Mo concentration was 105.4 ± 3.1 nmol/kg and δ98/95Mo was 2.36 ± 0.03 ‰ (n = 31) throughout the water column, congruent with those in the ocean. In the Uji River-Yodo River-Osaka Bay system, the W concentration reached 1074 pmol/kg and δ186/184W reached 0.20 ‰. We propose that the enrichment of W with a low δ186/184W in the river-estuary system and marginal seas is caused by anthropogenic pollution. Anthropogenic Mo pollution was not detected in marginal seas. However, the Mo concentration and δ98/95Mo showed high anomalies above the mixing line of river water and seawater in the lower Yodo River and Osaka Bay, implying possible anthropogenic pollution of Mo in the metropolitan area.

Arctic ice melt could trigger uncontrollable climate change at global level.

As part of the efforts exerted by INEGMA's "Counter-Piracy and Somalia Capacity-Building Program" (CPSCB) to spread awareness for the purpose of building expertise and providing recommendations with regards to maritime piracy off the coast of Somalia, the INEGMA team held discussions with Rear Admiral Antoine BEAUSSANT, Commander of the French Joint Force in the Indian Ocean , who deliberated on the latest developments, efforts, recommendations, as well as the upcoming agenda of ALINDIEN* and EUNAVFOR with regards to maritime piracy.

Fuzzy crab, shiny-eyed shrimp discovered on Java expedition.

Kenya needs tight laws to protect its rich ocean wealth.

'Seahorses endangered due to rising demand, fishing nets'.

Chlorophyll-a can be used as a proxy for phytoplankton and thus is an essential water quality parameter. The presence of phytoplankton in the ocean causes selective absorption of light by chlorophyll-a pigment resulting in change of the ocean color that can be identified by ocean color remote sensing. The accuracy of chlorophyll-a concentration (Chl-a) estimated from remote sensing sensors depends on the bio-optical algorithm used for the retrieval in specific regional waters. In this work, it is attempted to estimate Chl-a from two currently active satellite sensors with relatively good spatial resolutions considering ocean applications. Suitability of two standard bio-optical Ocean Color (OC) Chlorophyll algorithms, OC-2 (2-band) and OC-3 (3-band) in estimating Chl-a for turbid waters of the northern coastal Bay of Bengal is assessed. Validation with in-situ data showed that OC-2 algorithm gives an estimate of Chl-a with a better correlation of 0.795 and least bias of 0.35 mg/m3. Further, inter-comparison of Chl-a retrieved from the two sensors, Landsat-8 OLI and Sentinel-2 MSI was also carried out. The variability of Chl-a during winter, pre-monsoon, and post-monsoon seasons over the study region were inter-compared. It is observed that during pre-monsoon and post-monsoon seasons, Chl-a from MSI is over estimated compared to OLI. This work is a preliminary step toward estimation of Chl-a in the coastal oceans utilizing available better spatially resolved sensors.

Sea levels around the world have risen by 1.7 millimeters (0.07 inches) on average each year since 1880, but in recent years, scientists have observed a rapid increase in sea level in the north Indian Ocean. Tide gauge records and other datasets reveal the pace of sea level rise in the north Indian Ocean has accelerated to 3.1 millimeters (0.12 inches) per year within the last three decades.

In the Maldives, an MIT team is conducting experiments to combat sea-level rise by redirecting natural sand movement.

Marine soft-sediments sustain functionally important benthic assemblages that are critical for remineralization of organic matter and supply of nutrients to the water column. While these assemblages are well studied along continental margins, investigations from insular margin that surround oceanic islands are very limited. This paper examines the distribution and standing stock of macrozoobenthos at 50, 100, and 200 m depth contours surrounding the Andaman and Nicobar archipelago in the tropical Indian Ocean. The standing stock of macrozoobenthos decreased from the mesophotic reef areas (50 m depth) to the deeper strata (200 m), particularly in the case of the dominant groups, the polychaetes and crustaceans. Smaller-sized, interstitial polychaetes and crustaceans were abundant in the coarser sandy sediments at the shallower sites. The polychaetes were represented by 606 species (279 genera) in the study, of which >50% were rare species. Based on polychaete species composition, three regions were delineated in the study area - the Nicobar margin, the western margin of the Andaman (Bay of Bengal sector), and the eastern margin of the Andaman (Andaman Sea sector). The long, uninterrupted Andaman Island chain formed a geographic barrier separating the eastern and western margins, resulting in the regional distinctions in sediment nature and hydrographic characteristics, which in turn influenced species distribution. Corresponding differences were absent in the case of the Nicobar Islands, which are widely separated by transecting channels, permitting exchange of water between the Bay of Bengal and the Andaman Sea. Within the three regions, polychaete communities changed significantly in taxonomic and functional composition with increasing depth. The well oxygenated, coarse sandy sediments around mesophotic reefs (50 m) harbored predator-dominated assemblages. The 200 m sites, which were characterized by oxygen minimum conditions (<0.5 ml.l-1), particularly around th

Marine scientists have mapped previously unknown foraging grounds and migratory routes of Western Australia's green turtles to support conservation of the iconic threatened species.

The genus Scomberomorus, with 18 nominal species, sustains a significant heterogeneous fishery throughout its range. The sole molecular systematic study of this genus concerned the species group S. regalis, which contains the new world taxa. The species diversity of Scomberomorus in the northern Indian Ocean has not been studied at the molecular level, often leading to misidentifications...

Research May Also Help Determine Effects of Global Warming in the Region.

WA's SCOTT Reef has recovered from mass bleaching in 1998.

BoBBLE drones scour the oceans for data.

It sounds like a bad sci-fi plot: a fleet of 'bio robots' are let loose in the world's third largest ocean to study its physical and biological makeup.

Deadly, Rare Tropical Cyclone Hits Somalia.