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UN says cyclone hitting Yemen leaving 'extensive damage.

Extensive seagrass meadows discovered in Indian Ocean through satellite tracking of green turtles.

The Arabian Sea is a significant hypoxic region in world's oceans, characterized by the most extensive oxygen minimum zones (OMZs). Both physical and biological processes can alter the vertical and horizontal distribution of dissolved oxygen within the upper ocean and affect the spatial and temporal distribution of hypoxia within the OMZ. To identify the key physical and biological factors influencing the boundaries of oxycline, we analyzed an extensive dataset collected from the biogeochemical-Argo (BGC-Argo) floats during the period of 2010-2022. In particular, we investigated the impact of physical subduction events on the oxycline. Our results shows that the upper boundary of the oxycline deepened in summer and winter, and seemed to be controlled by the mixed layer depth. In contrast, it was shallower during spring and autumn, mainly regulated by the deep chlorophyll maximum. The lower boundary of the oxycline in the western Arabian Sea was predominantly controlled by regional upwelling and downwelling, as well as Rossby waves in the eastern Arabian Sea. Subduction patches originated from the Arabian Sea High Salinity Water (ASHSW) were observed from the BGC-Argo data, which were found to deepen the lower boundary of the oxycline, and increase the oxygen inventory within the oxycline by 8.3%, leading to a partial decrease in hypoxia levels.

Within atolls, deep water channels exert significant control over local hydrodynamic conditions; which are important drivers of planktonic distributions. To examine planktonic responses to oceanography, this study tested the effect of proximity and exposure to deep oceanic flushing through these channels on water properties and planktonic assemblages across four atolls (Diego Garcia, Salomon, Egmont, and Peros Banhos) in the British Indian Ocean Territory Marine Reserve. As this is the largest, most isolated and sparsely inhabited atoll complex in the world, it provides the perfect experimental conditions to test the effect of oceanic flushing without confounding factors related to anthropogenic development. Results are discussed in the context of ecosystem functioning. A total of 30 planktonic taxa and 19,539 individuals were identified and counted. Abundance was significantly different between atolls and significantly greater within inner regions in all atolls except southeast Egmont. Planktonic assemblage composition significantly differed between atolls and between inner and outer stations; exhibiting higher similarity between outer stations. Within outer stations of Diego Garcia, Peros Banhos, and Egmont, evidence suggesting oceanic flushing of cold, saline, and dense water was observed, however a longer time series is required to conclusively demonstrate tidal forcing of this water through deep water channels. Planktonic variability between inner and outer atoll regions demonstrates that broad comparisons between oceanic and lagoon regions fail to capture the complex spatial dynamics and hydrodynamic interactions within atolls. Better comprehension of these distributional patterns is imperative to monitor ecosystem health and functioning, particularly due to increasing global anthropogenic pressures related to climate change. The extensive coral bleaching described in this paper highlights this concern.

The present study is the first completed and taxonomically validated literature review of the biodiversity of barnacles (Cirripedia) in India. A total of 144 species in 75 genera and 19 families have been recorded in India. The highest number of species has been recorded from the Bay of Bengal province, located on the eastern side of the Indian Peninsula, comprising the Eastern India ecoregion (76 species) and Northern Bay of Bengal ecoregion (34 species). The West and South India Shelf province has fewer species (Western India ecoregion: 29 species; South India and Sri Lanka ecoregion: 40 species; and Maldives ecoregion: 10 species) compared to the Bay of Bengal province. The Andaman province is composed of the Andaman and Nicobar Islands, and contains 65 species. Most of the coral-associated barnacles (family Pyrgomatidae) have been recorded in the corals reefs of the Andaman and Nicobar Islands (7 species), Eastern India (6 species), and Northern Bay of Bengal ecoregions (5 species). Sponge-associated barnacles (mostly in the subfamily Acastinae) were recorded in the Eastern India ecoregion, Southern India and Sri Lanka, and Andaman and Nicobar Islands ecoregions. Deepwater species were recorded the most extensively in the Andaman and Nicobar Islands ecoregion (21 species), followed by the South India and Sri Lanka ecoregion (9 species) and Eastern India ecoregion (7 species). Six Atlantic/boreal cold water species previously reported in India were removed due to incorrect identification, and some incorrectly identified species were validated and corrected.

This study represents the first ROV-based exploration of the Perth Canyon, a prominent submarine valley system in the southeast Indian Ocean offshore Fremantle (Perth), Western Australia. This multi-disciplinary study characterizes the canyon topography, hydrography, anthropogenic impacts, and provides a general overview of the fauna and habitats encountered during the cruise. ROV surveys and sample collections, with a specific focus on deep-sea corals, were conducted at six sites extending from the head to the mouth of the canyon. Multi-beam maps of the canyon topography show near vertical cliff walls, scarps, and broad terraces. Biostratigraphic analyses of the canyon lithologies indicate Late Paleocene to Late Oligocene depositional ages within upper bathyal depths (200-700 m). The video footage has revealed a quiescent 'fossil canyon' system with sporadic, localized concentrations of mega- and macro-benthos (∼680-1,800 m), which include corals, sponges, molluscs, echinoderms, crustaceans, brachiopods, and worms, as well as plankton and nekton (fish species). Solitary (Desmophyllum dianthus, Caryophyllia sp., Vaughanella sp., and Polymyces sp.) and colonial (Solenosmilia variabilis) scleractinians were sporadically distributed along the walls and under overhangs within the canyon valleys and along its rim. Gorgonian, bamboo, and proteinaceous corals were present, with live Corallium often hosting a diverse community of organisms. Extensive coral graveyards, discovered at two disparate sites between ∼690-720 m and 1,560-1,790 m, comprise colonial (S. variabilis) and solitary (D. dianthus) scleractinians that flourished during the last ice age (∼18 ka to 33 ka BP). ROV sampling (674-1,815 m) spanned intermediate (Antarctic Intermediate Water) and deep waters (Upper Circumpolar Deep Water) with temperatures from ∼2.5 to 6°C. Seawater CTD profiles of these waters show consistent physical and chemical conditions at equivalent depths between dive

The silver-lipped pearl oyster, Pinctada maxima, is the primary species used for the culture of pearls in the Indo-Pacific region. The Western Australian fishery relies on wild-caught animals, and as such, knowledge of the status and distribution of P. maxima underpins sustainable management of the fishery. Eighty Mile Beach, in tropical Western Australia, is the key harvest area for P. maxima, with oysters collected by divers to depths of ∼35 m, although there are anecdotal accounts of oysters beyond diving depths. Image-based, and acoustic methods were used to elucidate distribution patterns of P. maxima off Eighty Mile Beach, including data from 862 km2 of multibeam survey and 119 towed video transects spanning an area from the 20 to 100 m contour lines. We quantified habitat characters including depth, substrate, and benthic community composition associated with pearl oyster distribution. Multibeam sonar data was also coupled with towed video data to produce predictive statistical models of P. maxima habitat. We found P. maxima to depths of 76 m, although more than 90% of individuals occurred shallower than 40 m and less than 2% were found deeper than 50 m. Oysters occupied flat, sandy habitats with neighbouring benthic communities of filter feeders (>98% of observations). These results show P. maxima predominantly occurs in depths <40 m, with no evidence that extensive populations extend into deep water in the region.

The role of COVID-19 pandemic lockdown in improving air quality was reported extensively for land regions globally. However, limited studies have explored these over oceanic areas close to high anthropogenic activities and emissions. The Bay of Bengal (BoB) basin is one such region adjacent to the highly populated South Asian region. We find that Aerosol Optical Depth (AOD) over the BoB declined by as much as 0.1 or 30% during the peak lockdown of April 2020 compared to long-term climatology during 2003-2019. Simultaneously, the sea surface temperature (SST) rose by 0.5-1.5°C over the central and north-western parts of the BoB with an average increase of 0.83°C. We show that up to 30% of this observed warming is attributable to reduced atmospheric aerosols. The study highlights the importance of anthropogenic emissions reduction due to COVID lockdown on short-term changes to SST over ocean basins with implications to regional weather.

The recently discovered Onnuri hydrothermal vent field (OVF) is a typical off-axis ultramafic-hosted vent system, located on the summit of the dome-like ocean core complex (OCC) at a distance of ∼12 km from the ridge axis along the middle region of the Central Indian Ridge (CIR). The plume chemistry with high methane anomaly was consistent with the precursor of hydrothermal activity; however, the fundamental characteristic of the OVF system, such as the hydrothermal circulation process and source of heat, remains poorly understood. Here, we focus on the geochemical features of surface sediments and minerals collected at and around the OVF region in order to better understand this venting system. The results reveal that the OVF sediments are typified by remarkably high concentrations of Fe, Si, Ba, Cu, and Zn, derived from hydrothermal fluid and S and Mg from seawater; depleted C-S isotope compositions; and abundant hydrothermally precipitated minerals (i.e., Fe-Mn hydroxides, sulfide and sulfate minerals, and opal silica). Notably, the occurrence of pure talc and barite bears witness to strong hydrothermal activity in the OVF, and their sulfur and strontium isotope geochemistry agree with extensive mixing of the unmodified seawater with high-temperature fluid derived from the gabbroic rock within the ultramafic-dominated ridge segment. The findings reveal that the OVF is a representative example of an off-axis, high-temperature hydrothermal circulation system, possibly driven by the exothermic serpentinization of exposed peridotites. Given the widespread distribution of OCC with detachment faults, furthermore, the OVF may be the most common type of hydrothermal activity in the CIR, although the paucity of data precludes generalizing this result. This study provides important information contributing to our understanding of the ultramafic-hosted hydrothermal vent system with a non-magmatic heat source along mid-ocean ridges.

The Java Trench is the only subduction trench in the Indian Ocean that extends to the hadal zone (> 6,000 m water depth), and except for sevenbenthic trawls acquired around the 1950s, there has been little to no sampling at hadal depths undertaken since. In 2019, we undertook a 5-day expedition comprising a scientific dive using a full ocean depth-rated submersible, the DSV Limiting Factor, seven hadal-lander deployments, and high-resolution bathymetric survey. The submersible performed a video transect from the deepest point of the trench, up a 150 m high near-vertical escarpment located on the forearc, and then across a plateau at a depth of ∼7,050 m to make in situ observations of the habitat heterogeneity and biodiversity inhabiting these hadal depths. We found the Java Trench hadal community to be diverse and represented by 10 phyla, 21 classes, 34 orders and 55 families, with many new records and extensions in either depth or geographic range, including a rare encounter of a hadal ascidian. The submersible transect revealed six habitats spanning the terrain. The deepest trench axis comprised fine-grained sediments dominated by holothurians, whereas evidence of active rock slope failure and associated talus deposits were prevalent in near-vertical and vertical sections of the escarpment. Sediment pockets and sediment pouring down the steep wall in "chutes" were commonly observed. The slope terrain was dominated by two species in the order Actiniaria and an asteroid, as well as 36 instances of orange, yellow, and white bacterial mats, likely exploiting discontinuities in the exposed bedrock, that may indicate a prevalence of chemosynthetic input into this hadal ecosystem. Near the top of the escarpment was an overhang populated by > 100 hexactinellid (glass) sponges. The substrate of the plateau returned to fine-grained sediment, but with a decreased density and diversity of epifauna relative to the trench floor. By providing the first visual insights of the h

The Introduction of this paper argues that current coastal and ocean management approaches like marine spatial planning (MSP) often do not adequately acknowledge and integrate Indigenous and Local Knowledge (ILK). This is problematic because how humans value and perceive coastal and marine resources is integrally linked to how they use and manage these resources, especially in adapting to social-ecological change. Coastal and marine resources are situated within complex social-ecological systems that are culturally, economically, historically and politically embedded. Therefore, management approaches have to integrate transdisciplinary and contextual perspectives in order to be relevant, sustainable and adaptive. Following extensive research in Algoa Bay, South Africa this article highlights several pathways to bridge the gap between existing ILK and current coastal and ocean management approaches. The Methods section discusses how the authors worked in tandem with a bottom-up (engaging with Indigenous and local coastal and marine resource users) and top-down (engaging with coastal governance authorities and practitioners) approach. In order to answer the primary research question "How can ILK be integrated into area-based ocean management like MSP"? the authors employed arts-based participatory methods as well as in-depth interviews and workshops with coastal governance authorities and practitioners over several months. This work then culminated in a one-day multi-stakeholder workshop which brought both ILK holders and coastal authorities and practitioners together to collaboratively identify pathways to integrate this knowledge into coastal and ocean management. In the Results and Discussion section the authors present and discuss five co-identified pathways to integrate ILK in coastal and ocean management which include: adopting contextual approaches to coastal and ocean management; increasing transparency and two-way communication between coastal authorities and

International Fisheries Law (IFL) provides innovative approaches to fisheries governance at national levels. The emergence of Sustainable Development Goal 14 (SDG 14) is phenomenal for fisheries because it creates new means for implementing IFL. Under SDG 14, fisheries governance for sustainable fisheries has become a complex and challenging task for any state. Developing States like Pakistan are struggling to achieve SDG 14 with new approaches to fisheries governance. The current situation of fisheries governance in Pakistan motivated the content of this research paper. This research paper adopted the comprehensive literature review (CLR) methodology to analyse existing fisheries governance mechanisms in Pakistan. Besides CLR, the paper also analysed a 'case study' on fisheries governance of Pakistan entitled 'National Policy and Strategy for Marine Fisheries. Furthermore, one hundred sixty-seven research articles and national and international legislation on fisheries governance from 2010 - 2023 are analysed. The results of the CLR methodology suggested that an extensive integrated mechanism under a comprehensive framework should be developed for fisheries governance. The framework forwarded a policy mechanism incorporating sustainable development goals with SDG 14 that should be implemented coherently for sustainable fisheries. The discussion followed the analysis and suggested that regional to local and bottom-up and top-down approaches in fisheries governance are required to address the challenges to sustainable fisheries in Pakistan. The conclusion of the discussion portrayed that future research related to fisheries governance in Pakistan shall be based on the practical implementation of SDG 14.

Kenya urges Africa to expand ports to spur maritime trade.

Japan lends $270m to Kenya to help expand port.

Reprieve for ABBOTT's booby after Christmas Island mining expansion ruled out.

India Spends $1.9Bln On Port Expansion.

Residents say their lives and livelihoods are at risk from a proposed expansion of India's Kattupalli Port.

Ports and neighbouring cities function as connectors between land and water and have long accommodated a substantial flow of goods and services. Port cities in the Western Indian Ocean (WIO) region and the Global South (GS) are rapidly and inevitably expanding as the demand for global trade increases. However, this expansion has numerous impacts on the surrounding marine ecosystem and the socio-economic livelihoods of local communities. We propose a framework to evaluate the sustainability of port cities in the WIO region and more broadly for cities in the GS. Through an exploratory approach, a systematic literature review (SLR) was undertaken to identify existing themes on port city and marine ecosystem sustainability indicator frameworks. The results revealed a strong bias towards sustainability publications designed for port cities in Global North. The approach developed from this study focuses on the socio-economic and environmental attributes relevant to ports in the WIO region and for GS countries. This draws from the Drivers, Pressures, States, Impacts and Responses (DPSIR) framework and includes 78 indicators. The indicators are designed to identify and report on the complex land and sea interdependencies of port cities. To test the validity of these indicators their interdependencies were examined through a Causal Network (CN) structure which identified 12 priority DPSIR CN. These were also mapped to the UNSDGs enabling the wider applicability and transferability of the framework. The resulting framework enables port cities in emerging economies to establish robust sustainable reporting systems and provides a framework that offers a unique lens for evaluating interactions embedded in the land and sea continuum.