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Iodine affects the radiative budget and the oxidative capacity of the atmosphere and is consequently involved in important climate feedbacks. A fraction of the iodine emitted by oceans ends up in aerosols, where complex halogen chemistry regulates the recycling of iodine to the gas-phase where it effectively destroys ozone. The iodine speciation and major ion composition of aerosol samples collected during four cruises in the East and West Pacific and Indian Oceans was studied to understand the influences on iodine's gas-aerosol phase recycling. A significant inverse relationship exists between iodide (I-) and iodate (IO3-) proportions in both fine and coarse mode aerosols, with a relatively constant soluble organic iodine (SOI) fraction of 19.8% (median) for fine and coarse mode samples of all cruises combined. Consistent with previous work on the Atlantic Ocean, this work further provides observational support that IO3- reduction is attributed to aerosol acidity, which is associated to smaller aerosol particles and air masses that have been influenced by anthropogenic emissions. Significant correlations are found between SOI and I-, which supports hypotheses that SOI may be a source for I-. This data contributes to a growing observational dataset on aerosol iodine speciation and provides evidence for relatively constant proportions of iodine species in unpolluted marine aerosols. Future development in our understanding of iodine speciation depends on aerosol pH measurements and unravelling the complex composition of SOI in aerosols.

Alvinellids have long been considered to be endemic to Pacific vents until recent discovery of their presence in the Indian Ocean. Here, a new alvinellid is characterized and formally named from recently discovered vents, Wocan, and Daxi, in the northern Indian Ocean. Both morphological and molecular evidences support its placement in the genus Paralvinella, representing the first characterized alvinellid species out of the Pacific. The new species, formally described as Paralvinella mira n. sp. herein, is morphologically most similar to Paralvinella hessleri from the northwest Pacific, but the two species differ in three aspects: (1), the first three chaetigers are not fused in P. mira n. sp., whereas fused in P. hessleri; (2), paired buccal tentacles short and pointed in P. mira but large and strongly pointed in P. hessleri; (3), numerous slender oral tentacles ungrouped in P. mira but two groups in P. hessleri. Phylogenetic inference using the concatenated alignments of the cytochrome c oxidase I (COI), 16S rRNA and 18S rRNA genes strongly supports the clustering of P. mira with two West Pacific congeners, P. hessleri and an undescribed species (Paralvinella sp. ZMBN). The resulting Indian/West Pacific lineage suggests a possible invasion into the Indian Ocean from the West Pacific. This is the third polychaete reported from Wocan hydrothermal field. Among the three species, two including P. mira and Hesiolyra heteropoda (Annelida:Hesionidae) are present in high abundance, forming an alvinellids/hesionids-dominated polychaete assemblage distinct from that at all other Central Indian Ridge and Southwest Indian Ridge vents. Thus, this study expands our understanding of alvinellid biogeography beyond the Pacific, and adds to the unique biodiversity of the northern Indian Ocean vents, with implications for biogeographic subdivision across the Indian Ocean ridges.

As a bio]diversity hotspot, the East Indies (Coral) Triangle possesses the highest biodiversity on the earth. However, evolutionary hypotheses around this area remain controversial; e.g., center of origin, center of accumulation, and center of overlap have been supported by different species. This study aims to answer the evolutionary influence of the Indonesian Seaway on the biodiversity of the Coral Triangle by recovering the evolutionary origins of a wide-ranging ommastrephid squid (Sthenoteuthis oualaniensis) based on integrated molecular and oceanographic clues from the Indo-Pacific. Three new clades were revealed; viz., clade I from the South China Sea, clade II from the northern East Indian Ocean, and clade III from the southern East Indian Ocean. These two Indian Ocean clades formed a monophyly closely related to clade IV from the Central-Southeast Pacific. Clade VI from the central Equatorial Pacific and clade V from the northern Eastern Pacific sit in basal positions of phylogenetic trees. Ancestral Sthenoteuthis was inferred to have originated from the Atlantic Ocean and sequentially dispersed to the northern East Pacific, central Equatorial Pacific, and West Pacific through the open Panama Seaway and being transported by westward North Equatorial Current. The East Indian Ocean was likely colonized by an ancestral population of clade IV from the Southeast Pacific. Westward South Equatorial Circulation could have promoted transoceanic migration of S. oualaniensis through the wide paleo-Indonesian Seaway. Sea level regression since the Miocene and the closure of the Indonesian Seaway at 4-3 Ma were responsible for the population genetic differentiation of S. oualaniensis in the Indo-Pacific. Therefore, the Indonesian Gateway played an important role in influencing marine organisms' migration and population differentiation through controlling and reorganizing circulations in the Indo-Pacific.

In Bangladesh, fishing communities are one of the most climate-vulnerable groups, though they play an important role in economic development. The main objective of this study was to identify vulnerability by exploring exposure (i.e., lack of regulating services or household capitals), susceptibility (i.e., lack of access to provisioning services), and lack of resilience (i.e., lack of alternative livelihoods and capacity) and to explore adaptation options, and challenges to understand risk governance. The study considered 45 published research articles for analysis following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Keywords were used in combinations (e.g., fishing communities and Bangladesh) to identify and screen published articles. Articles published in English focusing on vulnerability and/or risk governance, published between 2011 and 2022, featuring original empirical data or a comprehensive systematic review, and published in peer-reviewed journals were included. Articles were excluded if vulnerability and risk governance were evaluated but did not fit or match the definition used in this study. The study found frequent disasters and ocean warming caused different stresses, such as reduced fish catch and income, and resulted in an increased risk of fisheries conflict. Moreover, fishing communities have limited access to properties, modern fishing equipment, financial institutions, and fisher-centered organizations. Adaptation strategies include ecosystem-based (e.g., plantation, payment for ecosystem services) and non-ecosystem-based (e.g., temporary migration, getting help from neighbors) approaches. To boost fish production, the Government of Bangladesh instituted fishing restrictions and social safety net programs (e.g., distributing rice during the fishing restrictions); both initiatives were helpful. However, the conservation policies are not being implemented properly, and there is no particular social welfa

Over 24 hours of intense work has left the inside of Louis BURTON's IMOCA Bureau Vallée in a mess but the third placed skipper confirmed this morning that his efforts, in collaboration with his shore team, have kept him in the race. Speaking on the 0400hrs TU call this morning, after he had just gybed at the Antarctic Exclusion Zone he said, "I'm pretty burnt out and I admit that I came close to having to abandon". True to the philosophy of many competitors BURTON was not giving everything away about his problems, other than having said earlier that he had automatic pilot troubles.

Coastal upwelling is an oceanographic process that brings cold, nutrient-rich waters to the ocean surface from depth. These nutrient-rich waters help drive primary productivity which forms the foundation of ecological systems and the fisheries dependent on them. Although coastal upwelling systems of the Western Indian Ocean (WIO) are seasonal (i.e., only present for part of the year) with large variability driving strong fluctuations in fish catch, they sustain food security and livelihoods for millions of people via small-scale (subsistence and artisanal) fisheries. Due to the socio-economic importance of these systems, an "Upwelling Watch" analysis is proposed, for producing updates/alerts on upwelling presence and extremes. We propose a methodology for the detection of coastal upwelling using remotely-sensed daily chlorophyll-a and Sea Surface Temperature (SST) data. An unsupervised machine learning approach, K-means clustering, is used to detect upwelling areas off the Somali coast (WIO), where the Somali upwelling - regarded as the largest in the WIO and the fifth most important upwelling system globally - takes place. This automatic detection approach successfully delineates the upwelling core and surrounds, as well as non-upwelling ocean regions. The technique is shown to be robust with accurate classification of out-of-sample data (i.e., data not used for training the detection model). Once upwelling regions have been identified, the classification of extreme upwelling events was performed using confidence intervals derived from the full remote sensing record. This work has shown promise within the Somali upwelling system with aims to expand it to the rest of the WIO upwellings. This upwelling detection and classification method can aid fisheries management and also provide broader scientific insights into the functioning of these important oceanographic features.

Marine police of Coastal Security Group (CSG) have seized about 200 kg of sea endangered cucumbers, protected under Schedule I of the Wildlife Protection Act, 1972, and detained a man, who procured th

Marine police of Coastal Security Group (CSG) have seized about 200 kg of sea endangered cucumbers, protected under Schedule I of the Wildlife Protection Act, 1972, and detained a man, who procured th

A key component of successful coastal management efforts is an effective communication and engagement strategy focused on raising awareness of a region to different stakeholders to encourage more pro-environmental behaviors. Accordingly, in recent times there has been a proliferation of research focused on improving engagement and communication with different users of the coastal environment. Despite this effort, a paucity of evidence is available to guide better communication and engagement with visitors (i.e., tourists). Addressing this knowledge gap is critical given the adverse impacts of current global coastal tourism on ecosystem health, and projected future increases in coastal tourism. Using a case study of the Ningaloo Coast World Heritage Area (WHA) in Australia, we contribute toward filling this gap by identifying visitors' perception of the region and their self-reported and intended pro-environmental behaviors. We also identify the types of information they access and trust, and explore whether different message framings on the value of the WHA influence visitors' intended pro-environmental behavior. We determine that although visitors to the Ningaloo Coast WHA are optimistic about the future sustainability of the region, they have low understanding of the rules and regulations in place to support its management. Further, we find that visitors consider tourism to be a serious threat to the future of the region. However, most participants in our study considered the quality of their own environmental behavior to be high, and thus not contributing to these threats, although this did differ by gender. Finally, we highlight that visitors to the Ningaloo Coast WHA, for the most part, obtain their knowledge of the region during their visit, primarily through local signage and visitors centers. We discuss the implications of these results, and highlight future considerations for coastal managers when developing visitor-focused communication and engagement stra

Two severe heat waves triggered coral bleaching and mass mortality in the Maldives in 1998 and 2016. Analysis of live coral cover data from 1997 to 2019 in shallow (5 m depth) reefs of the Maldives showed that the 1998 heat wave caused more than 90% of coral mortality leaving only 6.8 ± 0.3% of survived corals in all the shallow reefs investigated. No significant difference in coral mortality was observed among atolls with different levels of human pressure. Maldivian reefs needed 16 years to recover to the pre-bleaching hard coral cover values. The 2016 heat wave affected all reefs investigated, but reefs in atolls with higher human pressure showed greater coral mortality than reefs in atolls with lower human pressure. Additionally, exposed (ocean) reefs showed lower coral mortality than those in sheltered (lagoon) reefs. The reduced coral mortality in 2016 as compared to 1998 may provide some support to the Adaptive Bleaching Hypothesis (ABH) in shallow Maldivian reefs, but intensity and duration of the two heat waves were different. Analysis of coral cover data collected along depth profiles on the ocean sides of atolls, from 10 to 50 m, allowed the comparison of coral mortality at different depths to discuss the Deep Refuge Hypothesis (DRH). In the upper mesophotic zone (i.e., between 30 and 50 m), coral mortality after bleaching was negligible. However, live coral cover did not exceed 15%, a value lower than coral survival in shallow reefs. Low cover values of corals surviving in the mesophotic reefs suggest that their role as refuge or seed banks for the future recovery of some species in shallow-water reefs of the Maldives may be small. The repeatedly high coral mortality after bleaching events and the long recovery period, especially in sites with human pressure, suggest that the foreseen increased frequency of bleaching events would jeopardize the future of Maldivian reefs, and ask for reducing local pressures to improve their resilience.

The next 24 hours will be the most challenging so far for Vendée Globe race leader Charlie DALIN (Apivia), especially through this evening and tonight as he will pass as close as he dare to the centre of a Southern Ocean low pressure system which is forecast to bring him gusts over 55kts and big seas. He told his team yesterday 'this is the biggest, most powerful storm I have had through since the start'. So today will mostly be about pushing on and preparing himself and his Apivia.

Having struck something in the water last night Sam DAVIES this morning is heading out of the worst of the weather and the sea state to further assess the damage to Initiatives Coeur. She spoke to Vendee Globe HQ this morning.

Ocean primary production is the basis of the marine food web, sustaining life in the ocean via photosynthesis, and removing carbon dioxide from the atmosphere. Recently, a small but significant decrease in global marine primary production has been reported based on ocean color data, which was mostly ascribed to decreases in primary production in the northern Indian Ocean, particularly in the Bay of Bengal. Available reports on primary production from the Bay of Bengal (BoB) are limited, and due to their spatial and temporal variability difficult to interpret. Primary production in the BoB has historically been described to be driven by diatom and chlorophyte clades, while only more recent datasets also show an abundance of smaller cyanobacterial primary producers visually difficult to detect. The different character of the available datasets, i.e., direct counts, metagenomic and biogeochemical data, and satellite-based ocean color observations, make it difficult to derive a consistent pattern. However, making use of the most highly resolved dataset based on satellite imaging, a shift in community composition of primary producers is visible in the BoB over the last 2 decades. This shift is driven by a decrease in chlorophyte abundance and a coinciding increase in cyanobacterial abundance, despite stable concentrations of total chlorophyll. A similar but somewhat weaker trend is visible in the Arabian Sea, where satellite imaging points towards decreasing abundances of chlorophytes in the north and increasing abundances of cyanobacteria in the eastern parts. Statistical analysis indicated a correlation of this community change in the BoB to decreasing nitrate concentrations, which may provide an explanation for both the decrease in eukaryotic nitrate-dependent primary producers and the increase in small unicellular cyanobacteria related to Prochlorococcus, which have a comparably higher affinity to nitrate. Changes in community composition of primary producers and an

In recent years, shoreline determination has become an issue of increasing importance and concern, especially at the local level, as sea level continues to rise. This study identifies the rates of absolute and net erosion, accretion, and shoreline stabilization along the coast of Kuakata, a vulnerable coastal region in south-central Bangladesh. Shoreline change was detected by applying remote sensing and geographic information system (RS-GIS)-based techniques by using Landsat Thematic Mapper (TM), Landsat 8 Operational Land Imager (OLI) and Thermal Infrared Sensor (TIRS) satellite images at 30-m resolution from 1989, 2003, 2010, and 2020. The band combination (BC) method was used to extract the shoreline (i.e., land-water boundary) due to its improved accuracy over other methods for matching with the existing shoreline position. This study also used participatory rural appraisal (PRA) tools which revealed the societal impacts caused by the shoreline changes. Coupling RS-GIS and PRA techniques provides an enhanced understanding of shoreline change and its impacts because PRA enriches the RS-GIS outcomes by contextualizing the findings. Results show that from 1989 to 2020, a total of 13.59 km2 of coastal land was eroded, and 3.27 km2 of land was accreted, suggesting that land is retreating at about 0.32 km2 yr-1. Results from the PRA tools support this finding and demonstrate that fisheries and tourism are affected by the shoreline change. These results are important in Kuakata, a major tourist spot in Bangladesh, because of the impacts on fisheries, recreation, resource extraction, land use planning, and coastal risk management.

As the climate crisis persists, there is a crucial need to increase knowledge on adaptive capacity and the underlying factors building it. This is particularly important for disadvantaged groups, such as coastal women in East Africa. Women's livelihoods in these seascapes are and will be more severely affected by climate change and the capacity of East African states to deal with these challenges is limited in terms of financial and human capital. In this research, we investigated the underlying factors building the adaptive capacity of coastal women in Zanzibar (Unguja Island), Tanzania. Coastal women (N=117) were interviewed in villages around the island to gather information about potential factors supporting adaptive capacity. This was analysed applying Cinner et al (2018) five domains typology for adaptive capacity, i.e. assets, flexibility, organizations, learning and agency. The results show that women had relatively low adaptive capacity, extended poverty and very high dependence on seaweed farming of red algae, a livelihood providing low income and already being seriously affected by climate variability and change. Women's observations of key variables related to environmental changes corresponded to most scientific findings. It was, however, unclear how that knowledge is useful and enhances adaptive capacity. Adaptive capacity was generally low but individual differences were found in which ten women had a high income. The results show that the factors underlying adaptive capacity are complex and interact with each other, being positive, negative and unclear. Many of the identified factors deserve future research. This study adds to the pool of knowledge by addressing women (not only men); coastal ecosystems (as land and freshwater systems are more studied) and the individual level (since most studies focus on national and community levels). The study illustrates that institutional renewal, bridging and cooperation is possible in Zanzibar bringing good new

Monthly composites of remote sensing reflectance at 555 nm wavelength (Rrs555) from ocean color imagery of the MODIS sensor onboard the Aqua platform were used to characterize the spatial and temporal variability of coastal plume in the Sofala Bank and its relation to river discharge, local rainfall, and wind speed. To achieve the objective, maps of monthly composites of Rrs555 over the Sofala Bank were inspected and statistical analysis was performed, including correlation, analysis of variance, and wavelet coherence between environmental variables and both plume area and Rrs555. Climatology of Rrs555 revealed that both plume dispersion and Rrs555 values are higher during June to December and lower during January to May. A positive correlation (r = 0.77) between wind speed and monthly time series of Rrs555, and a negative correlation between the Zambezi river discharge (r = −0.21) and rainfall (r = −0.67) with Rrs555 were found. These results suggest that variation of suspended matter in the Sofala Bank is mainly controlled by erosion and re-suspension by winds rather than the input of terrigenous matter by the Zambezi River discharge and rainfall, assuming that Rrs555 can be a valid proxy for the inorganic suspended matter. The southern portion of the Sofala Bank (i.e., near the mouths of the Pungue and Buzi Rivers) presented higher values of Rrs555 if compared to the center region near Zambezi river mouth and the northern region near Licungo river mouth. The higher Rrs555 values in the southern region might be associated with higher re-suspension rates due to increased tide mixing, dredging activities, and the shallower nature of bathymetry in the southern region. The dominance of wind in controlling the variability of suspended sediments and the eventual relatively greater contribution of Pungue and Buzi River than the Zambezi in supplying sediments could represent an evidence of weakening of Zambezi River supply of sediments, a process that might have start

Around the world, declines in the mean size of nesting sea turtles have been reported with concerns of a concomitant decrease in the reproductive output of populations. Here, we explore this possibility using long-term observations of green turtles (Chelonia mydas) at Aldabra Atoll, Seychelles. Based on > 4500 individual measurements over 21 years (1996-2016), we found the curved carapace length of nesting females declined by about 0.64 cm per decade, from 111.43 to 110.08 cm. For 391 individuals that were measured more than once with measurement interval of 2.8-19 years apart, the mean growth rate was 0.14 cm year−1. Comparisons between the size of adult females and males were based on 23 and 14 weight measurements, 107 and 33 carapace length measurements and 103 and 33 carapace width measurements, respectively, taken during 1981-1983. Adult females were larger than males, with the sexual dimorphism index, i.e. the ratio of size of the larger sex to the smaller, being 1.09 and 1.10 for carapace length and width, respectively, and 1.25 for weight. Smaller females tended to lay fewer eggs per clutch but the decrease in female mean size was accompanied by increases in numbers of turtles nesting annually, such that the estimated total numbers of eggs per year increased from 1.3 million to 2.0 million between 1996 and 2016. Therefore, a decrease in mean size of nesting females has not compromised egg production for this population.

The marine environment is most vital and flexible with continual variations in salinity, temperature, and pressure. As a result, bacteria living in such an environment maintain the adaption mechanisms that are inherent in unstable environmental conditions. The harboring of metal-resistant genes in marine bacteria contributes to their effectiveness in metal remediation relative to their terrestrial counterparts. A total of four mercury-resistant bacteria (MRB) i.e. NIOT-EQR_J7 (Alcanivorax xenomutans); NIOT-EQR_J248 and NIOT-EQR_J251 (Halomonas sp.); and NIOT-EQR_J258 (Marinobacter hydrocarbonoclasticus) were isolated from the equatorial region of the Indian Ocean (ERIO) and identified by analyzing the 16S rDNA sequence. The MRBs can reduce up to 70% of Hg(II). The mercuric reductase (merA) gene was amplified and the mercury (Hg) volatilization was confirmed by the X-ray film method. The outcomes obtained from ICP-MS validated that the Halomonas sp. NIOT-EQR_J251 was more proficient in removing the Hg from culture media than other isolates. Fourier transform infrared (FT-IR) spectroscopy results revealed alteration in several functional groups attributing to the Hg tolerance and reduction. The Gas Chromatography-Mass Spectrometry (GC-MS) analysis confirmed that strain Halomonas sp. (NIOT-EQR_J248 and NIOT-EQR_J251) released Isooctyl thioglycolate (IOTG) compound under mercury stress. The molecular docking results suggested that IOTG can efficiently bind with the glutathione S-transferase (GST) enzyme. A pathway has been hypothesized based on the GC-MS metabolic profile and molecular docking results, suggesting that the compound IOTG may mediate mercuric reduction via merA-GST related detoxification pathway.

Hydrothermal vent areas have drawn increasing interest since they were discovered in 1977. Because of chemoautotrophic bacteria, they possess high abundances of vent endemic species as well as many non-vent species around the fields. During the survey conducted by the Bundesanstalt für Geowissenschaften und Rohstoffe (Federal Institute for Geosciences and Natural Resources, BGR) to identify inactive polymetallic sulfide deposits along Central and Southeast Indian Ridges, the INDEX project studied the scavenging amphipod community at three newly discovered hydrothermal fields. A sample consisting of 463 representatives of Amphipoda (Malacostraca: Crustacea) was collected by means of baited traps in active and inactive vents of three different sites and subsequently studied by both morphological and genetic methods. Molecular methods included the analysis of two mitochondrial (cytochrome c oxidase subunit I [COI] and 16S rRNA) and one nuclear (18S rRNA) genes. By six delimitation methods, 22 molecular operational taxonomic units (MOTUs) belonging to 12 genera and 10 families were defined. The existence of potential species complexes was noted for the representatives of the genus Paralicella. The inactive site, where 19 species were found, showed higher species richness than did the active one, where only 10 taxa were recorded. Seven genera, Ambasiopsis, Cleonardo, Eurythenes, Parandania, Pseudonesimus, Tectovalopsis, and Valettiopsis, were observed only at inactive sites, whereas Haptocallisoma, was collected exclusively at active ones. The species Abyssorchomene distinctus (BIRSTEIN and VINOGRADOV, 1960), Hirondellea brevicaudata Chevreux, 1910, and Hirondellea guyoti (BARNARD and INGRAM, 1990), have been previously reported from vent sites in the Atlantic or Pacific oceans. The present study provides the first report of Eurythenes magellanicus (H. Milne Edwards, 1848) and five other already described species in the Indian Ocean. The addition of 356 sequences strong

The radula is the main feeding organ and also very significant to the majority of the mollusks (especially gastropod) taxonomy. With shell morphology, radular morphology is the key characteristic for the identification of gastropod species. The shape and structure of the radular teeth are unique from family to species level. In this study, five basic types of radula (i.e., docoglossan, rhipidoglossan, taenioglossan, stenoglossan, and toxoglossan), which were observed from a total of 23 different species belonging to 12 families, were examined. Collection of the voucher intertidal gastropod specimen for the study had initiated during May-October 2019 in the rocky intertidal area near Veraval of the south Saurashtra coastline. Direct handpicking methods were used for the collection of the specimen for experiments.

Major Tuna Vessel Is Denied Port Landing Because of Evidence of Illegal Fishing.