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Many marine megafauna taxa are tied to the sea surface for breathing which makes them vulnerable to vessel collisions. Sea turtles have developed efficient mechanisms to reduce surface time for breathing to a few seconds, but they can extend their surface periods to rest or to rewarm after diving into deep and colder waters. However, knowledge of collision occurrences is limited to data of turtles stranded along the coastline worldwide, whereas events occurring offshore go likely underestimated due to the sinking of carcasses. Here we performed a spatially explicit assessment to identify, for the first time, oceanic areas of higher exposure for sea turtles from maritime traffic in the Tyrrhenian Sea, Western Mediterranean. Satellite-tracking data were used to estimate utilization distributions of loggerhead turtles using Brownian bridge kernel density estimation. Maritime traffic density maps based on Automatic Identification System (AIS) data were extracted from open-access data layers, provided by the European Maritime Safety Agency, summarized, and used for the exposure analysis. Turtle occurrences were also investigated in response to vessel densities and seasonal patterns by fitting a generalized additive model to the data. Our results demonstrated that loggerhead turtles are potentially exposed to maritime traffic across the entire basin, especially in the easternmost part. the exposure varies among spring/summer and autumn/winter months. Highest turtle occurrences were found in regions primarily subjected to cargo, tanker, and passenger transportation. This study represents the first-ever effort to characterize the exposure of oceanic loggerhead turtles to maritime traffic and highlights oceanic areas of higher exposure where research and conservation efforts should be directed to understand the effective impact of this stressor on the species.

Global warming has led to rapid warming in the Arctic region and continuous melting of ice and snow, and the seaworthiness of the Arctic shipping routes is increasing significantly. This has also aroused widespread concern from the international community regarding the environmental impact of Arctic shipping activities. Thus, this paper reviews 75 articles to evaluate the different impacts of Arctic shipping on the region's environment. the research results show that the impact of current Arctic shipping activities is extensive, and it can identify three major impacts: impact on water bodies, impact of air emissions and impact on animal survival. In this context, to mitigate the growing negative impact of shipping activities on the fragile Arctic environment, it is essential to adopt technical and operational solutions for ships and formulate new or stricter standards and rules for Arctic shipping activities. At the same time, existing research has gaps in four areas: Arctic environmental and ecological baseline surveys, quantitative research on the direct and synergistic environmental impacts from Arctic shipping, implications of Arctic shipping activities on aboriginal health, and the Arctic shipping gas emission model based on artificial intelligence technology. We recommend enriching relevant research to enhance the ability to assess the impacts of Arctic shipping routes.

With the development of the marine economy, video surveillance has become an important technical guarantee in the fields of marine engineering, marine public safety, marine supervision, and maritime traffic safety. In video surveillance, maritime object detection (MOD) is one of the most important core technologies. Affected by the size of maritime objects, distance, day and night weather, and changes in sea conditions, MOD faces challenges such as false detection, missed detection, slow detection speed, and low accuracy. However, the existing object detection algorithms usually adopt predefined anchor boxes to search and locate for objects of interest, making it difficult to adapt to maritime objects' complex features, including the varying scale and large aspect ratio difference. therefore, this paper proposes a maritime object detection algorithm based on the improved convolutional neural network (CNN). Firstly, a differential-evolutionary-based K-means (DK-means) anchor box clustering algorithm is proposed to obtain adaptive anchor boxes to satisfy the maritime object characteristics. Secondly, an adaptive spatial feature fusion (ASFF) module is added in the neck network to enhance multi-scale feature fusion. Finally, focal loss and efficient intersection over union (IoU) loss are adopted to replace the original loss function to improve the network convergence speed. the experimental results on the Singapore maritime dataset show that our proposed algorithm improves the average precision by 7.1%, achieving 72.7%, with a detection speed of 113 frames per second, compared with You Only Look Once v5 small (YOLOv5s). Moreover, compared to other counterparts, it can achieve a better speed-accuracy balance, which is superior and feasible for the complex maritime environment.

Ship biofouling is a major vector for the introduction and spread of harmful marine species globally; however, its importance in Arctic coastal ecosystems is understudied. The objective of this study was to provide insight regarding the extent of biofouling (i.e., percent cover, abundance, and species richness) on commercial ships operating in the Canadian Arctic. A questionnaire was used to collect information on travel history, antifouling practices, and self-reported estimates of biofouling extent from ships operating in the region during 2015-2016. Twenty-five percent of ships operating in the region during the study period completed the questionnaire (n = 50). Regression trees were developed to infer the percent cover of biofouling, total abundance of fouling invertebrates, and fouling species richness on respondent ships based on previous underwater wetted surface assessments of commercial ships in Canada. Age of antifouling coating system was the only significant predictor of percent cover and total abundance of biofouling invertebrates, while the number of biogeographic realms previously visited and port residence time were significant predictors for fouling species richness. Comparison of relevant travel history features reported through the questionnaire to the regression tree models revealed that 41.9% of 43 respondent ships had antifouling coating systems older than 630 days and are therefore inferred to have relatively high (> 9.3%) biofouling percent cover. More than half of respondent ships (62.8%) had antifouling coating systems older than 354 days and are therefore inferred to have a relatively high total abundance (over 6,500 individuals) of fouling invertebrates. Nearly half of respondent ships (45.9% of 37 ships) had visited at least three biogeographic realms during their last 10 ports-of-call and are therefore inferred to have relatively high fouling species richness (mean 42 taxa). Self-reported estimates of biofouling cover were unreliable,

The application of a proactive grooming program to manage The fouling control coatings applied to ship hulls provides an opportunity to address The climate crisis, invasive species and The discharge of biocides into The marine environment. A large percentage of The total power required to propel a ship is to overcome The viscous drag created between The hull and The water. The powering penalty due to increases in coating roughness and The development of biofouling are well documented. In addition, poorly maintained fouling control coatings may lead to The transportation of invasive species. In-water hull cleaning is Therefore an important part of ship operations; however, this is typically implemented as a reactive measure when fouling reaches a critical level and requires powerful machinery which damages The coatings, creates unwanted discharge and in many locations The discharge will require capture and disposal. Ship hull grooming is being developed as a proactive method to manage fouling control coatings that will ensure that They are maintained in a smooth and fouling free condition, There is no transport of invasive species or excessive discharge of material that occurs during cleaning. This manuscript will summarize The findings of many years of research and development.

The inland waters around southern Vancouver Island and northern Washington State, known as the Salish Sea, host critical habitat for endangered southern resident killer whales (SRKW). This is, however, a highly traversed area, with approaches to industrial ports and coastal cities, international shipping lanes, ferry routes, and considerable recreational vessel traffic. Vessel noise is a key threat to SRKW prosperity, and so conservation measures directed to mitigate its effects have been explored annually since 2017. Here, we describe trials undertaken in 2020, which included spatially limited slowdown zones, exclusion areas as Interim whale Sanctuary Zones (ISZs), and a lateral displacement of tug transits to increase the distance between their route and SRKW foraging areas. To assess each of the measures we first considered the level of mariner participation using data from the Automated Identification Systems (AIS), mandatory for commercial vessels. Knowing this, the changes in soundscape were examined, focused on impacts on broadband (10 Hz to 100 kHz) ambient noise and the frequencies used by SRKW for communication (500 Hz to 15 kHz) and echolocation (15 to 100 kHz). A control period of two-months prior to trial initiation was used to quantify the changes. High levels (> 80%) of compliance were found for each measure, except ISZs, where observance was low. Median reduction in speeds ranged from 0.2-3.5 knots. Resulting sound reductions were most notable in the lower frequencies, although reductions were also recorded in SRKW pertinent ranges. Tug displacement also reduced ambient noise in these frequencies, despite making up a small portion of the overall traffic. the management trials were effective in reducing potential impacts singularly and in concert. Greater awareness and stakeholder engagement may increase compliance and, therefore, the efficacy of measures in the future.

With the COVID-19 pandemic came what media has deemed the "port congestion pandemic". Intensified by the pandemic, the commonplace anchoring of high-tonnage ships causes a substantial geomorphologial footprint on the seabed outside marine ports globally, but isn't yet quantified. We present the first characterisation of the footprint and extent of anchoring in a low congestion port in New Zealand-Aotearoa, demonstrating that high-tonnage ship anchors excavate the seabed by up to 80 cm, with the impacts preserved for at least 4 years. The calcuated volume of sediment displaced by one high-tonnage ship (> 9000 Gross Tonnage) on anchor can reach 2800 m3. Scaled-up globally, this provides the first estimates of the footprint of anchoring to the coastal seabed, worldwide. Seafloor damage due to anchoring has far-reaching implications for already stressed marine ecosystems and carbon cycling. As seaborne trade is projected to quadruple by 2050, the poorly constrained impacts of anchoring must be considered to avoid irreversible damage to marine habitats.

Seabed fluid flow is a widespread and important natural phenomenon in marine environments, which involves complex multi-physics, multi-process and multi-scale processes. The developments in offshore geophysical technology have facilitated The discovery of The widespread emissions of seabed fluids. For an overview on The state-of-The-art seabed fluid flow research and for obtaining a perspective on future research in The China Seas, we reviewed The data, reports, and publications particularly that associated with cold seeps such as pockmarks, seeps, domes, mud volcanoes, and gas hydrates in The Bohai Sea, The Yellow Sea, The East China Sea, and The South China Sea. This study presents The first report for seabed fluid flow on all China Seas with The basic information required to undertake additional analytical studies of These features. FurThermore, we explore processes responsible for Them and Their implications. Although The seabed fluid flow is widespread, dynamic, and influential, it is still poorly examined and understood. To understand seabed fluid flow in both time and space, it is important to investigate how and why These seabed fluids form and migrate.

Maritime transport is a major source of pollution of marine environment, which is the essential object in a series of international maritime legislations and various countries' domestic laws. Focused on protecting the marine environment, China has spent over 40 years developing the rule of law for marine environmental governance in maritime transport, including efforts made in legislation, law enforcement, and the judiciary. In this article, we attempt to examine China's experience and practice in the marine environment, explain the logic and consideration in relevant practices, and summarize China's paradigm for the rule of law for such governance. China has sought to resolve two major issues: the relationship between domestic and international law and the balance of interests between flag, coastal, and port states, offering a vivid model of marine environmental governance on which other countries can base their own legal systems. the findings reveal that with following and enforcing the international law of the sea, now China's domestic laws have form lawful authority on binding foreign vessels. China is continually strengthening the construction of its legislative system to harmonize inconsistencies and keep pace with international marine environmental law. To eliminate administrative inefficiency resulting from cumbersome procedures, China has reformed its maritime enforcement system by consolidating multiple administrations. China's independent maritime judicial system is meeting the demand to develop environmental specialization, enabling further exploitation of its profession in solving maritime environment cases and implementing environmental legislation.

Scandinavia is the first region in the world to rely increasingly on battery-powered and thus environmentally-friendly technologies in the shipbuilding industry. After "Ampere", the world's first electrical ferry in Norway, Siemens has received a follow-up order of the Finnish shipping company FinFerries. Ampere was put into operation in Norway in May 2015, and has traveled a distance equivalent to more than 1.5 times around the equator. With the change from diesel propulsion to battery, Norwegian ship owner Norled has reduced the cost of fuel by 60 percent. For FinFerries, SIEMENS has now tailor-made a suitable technical solution for Finland's first emission-free ferry. This follow-up order confirms SIEMENS' pioneer position delivering green solutions in the shipbuilding industry.

Scandinavia is the first region in the world to rely increasingly on battery-powered and thus environmentally-friendly technologies in the shipbuilding industry. After "Ampere", the world's first electrical ferry in Norway, Siemens has received a follow-up order of the Finnish shipping company FinFerries. Ampere was put into operation in Norway in May 2015, and has traveled a distance equivalent to more than 1.5 times around the equator. With the change from diesel propulsion to battery, Norwegian ship owner Norled has reduced the cost of fuel by 60 percent. For FinFerries, SIEMENS has now tailor-made a suitable technical solution for Finland's first emission-free ferry. This follow-up order confirms SIEMENS' pioneer position delivering green solutions in the shipbuilding industry.

On March 16 2017 the crew of the MT ARIS 13, a tanker vessel, was released from Somali pirate hands due to the efforts of the Puntland Maritime Police Force (PMPF). the entire crew is reported unharmed. Under the care of the PMPF, the MT ARIS 13 is now proceeding to the Somali port city of Bosasso. On 13 March, pirates hijacked the vessel en route to Mogadishu from Djibouti. the ship was seized approximately 18 km off the northern tip of Somalia. This incident marks the first hijacking of a large merchant vessel since the height of Somali piracy in 2012.

A healthy marine environment is integral to numerous New Zealand economic, social, and cultural values, including fisheries, aquaculture, tourism, and recreational and customary activities. The introduction and spread of marine non-indigenous species (NIS) via The vessel biofouling pathway may put These values at risk. Over The past two decades, The Ministry for Primary Industries (MPI) has been proactive in commissioning research focused on The risks associated with vessel biofouling, identification of potential risk vessels, and risk management options. In 2010, MPI consulted on options to manage The biofouling risks on all vessels entering New Zealand waters. In 2014, New Zealand became The first country to introduce mandatory biofouling requirements. Between 2014 and 2018, MPI focused on communicating The requirements to support stakeholder awareness, readiness, and uptake. In parallel, MPI commissioned furTher research to investigate proactive and reactive approaches to biofouling management. Research outcomes were summarized and technical advice provided to inform stakeholders of what constitutes best biofouling management practices. This review summarizes MPI's research and technical advice on The risks associated with vessel biofouling and its management, and The procedures followed to produce New Zealand's biofouling regulations. The development of These regulations is also contextualized in terms of New Zealand's marine biosecurity system. The transparent and evidence-based approach followed by MPI provides a blueprint for establishing biofouling regulations. Because These regulations are aligned with The International Maritime Organization guidelines, There is The potential to develop consistent global and domestic practices for managing marine NIS introduction and spread.

Globally, movements of commercial vessels can facilitate the spread of marine non-indigenous species (NIS) beyond their current biogeographic ranges. Authorities at potential destination locations employ a number of biosecurity risk assessment strategies to estimate threat levels from potential origin locations, vulnerability levels of specific destination regions, or the consequences of successful establishment of particular NIS species. Among the many factors and processes that have an influence on the probability that NIS will survive transport and establish successfully at new locations, vessel type has been identified as an important risk factor. Different vessel types have different structural and operational characteristics that affect their overall level of marine biosecurity risk. Several recent studies have examined subsets of vessel types or vessel characteristics for their ability to spread NIS. While high-quality information is available via these endeavors, it is fragmented and not readily available as an integrated resource to support biosecurity regulators or other end-users. In this study, we synthesize available empirical data on a wide range of vessel types and characteristics to develop a framework that allows systematic quantification of the relative risk of NIS transfer by common commercial vessel types. We explain our approach for constructing the framework, from selection of key risk factors for inclusion, to selection of which datasets to use for those risk factors. the framework output is a set of risk scores which denote the relative biosecurity risk of common commercial vessel types. To demonstrate a potential application of our framework, we applied the risk scores to vessel visit data for commercial ports around New Zealand and assigned a relative risk level per port based on the arrival frequencies of different vessel types. the resulting per-port risk levels matched closely with the results of a prior benchmark study that employed sta

Ocean observation system that involves multiple underwater vehicles and seafloor nodes plays an important role in better learning the ocean, where underwater wireless communication is mandatory for massive data interaction. Optical communication that has wide bandwidth and comprehensive working distance is the preferred method compared to acoustic and other methods. However, the presence of directionality makes the optical method difficult to use especially when the transceiver is equipped on a motive vehicle. In this study, an underwater free-space optical communication method of transmitting information is proposed. Characteristics of underwater optical transmission, as well as the photoelectric signal processing and modulation and demodulation algorithms, are studied and modeled. New approach for realizing underwater free-space optical communication is proposed and simulated. A prototype including a free-space optical transmitter and a receiver is developed; tests in different scenarios were carried out, and the results were observed: (1) by using the minimum number of LEDs, the effect of uniform lighting in space is achieved, and the transmitter coverage reaches 160°. (2) When the power of the transmitter is 10 W and the communication rate is 1 Mbps, the maximum communication distance reaches 13 m.

Uncertainties in port handling efficiency can cause port delays in the liner shipping system. Furthermore, policies on carbon emission reduction, such as EEXI standards, restrict the potential for speed optimization in liner shipping operations. Traditional tactical planning speed optimization is unsuitable for operational-level decision making, leading to unreliable schedules. From a schedule-reliability and energy-efficiency perspective, we propose a real-time speed optimization method based on discrete hybrid automaton (DHA) and decentered model predictive control (DMPC). We use a dynamic adjustment of sailing speed to offset the disturbance caused by port handling efficiency uncertainties. First, we establish a DHA model that describes each ship's hybrid dynamics of state switching between sailing and berthing; then, we develop a prediction model for the DMPC controller, which is analogous to the DHA model. the schedule is transferred into time-position coordinates as controller reference trajectories in the receding horizon speed optimization framework. We consider determining tracking errors, carbon emissions, and fuel consumption as our objectives, and we carry out engine power limitation (EPL) analysis for the sample ship, which turns the EEXI standards into constraints. We attain the recommended speed by solving a mixed-integer optimization. We carry out a case study, and our results indicate the effectiveness of our proposed DHA-DMPC scheme in lowering port delays and achieving the best trade-off between schedule reliability and energy efficiency. Additionally, we conduct further experiments to analyze the impacts of various carbon reduction policies on the performance levels of liner shipping operations.

The ocean industries are characterized by being export-driven. The exports of ocean industries (hereafter termed ocean exports) caused environmental pollution with amounts of CO2 emissions and Thereby affected climate change. There is a need, Therefore, for accurate assessments of CO2 emissions embodied in ocean exports-which can help policymakers adopt targeted emission-reduction measures to formulate sustainable ocean policies. However, few studies of ocean-industry emissions considered impacts in sectoral and trade pattern heterogeneity, especially from export perspective. To fill this gap, we measured and evaluated The export-embodied CO2 emissions from China's ocean industries, based on our newly developed high-resolution and comparable time-series environmentally extended input-output database, called EE-DPN-OEIOT. The results showed that China's ocean exports generated 94.3 Mt of embodied CO2 emissions in 2017, with nearly 40% originating from processing ocean exports. Regarding The evolution from 2007 to 2017, The total export-embodied CO2 emissions from ocean industries decreased by 7.3%, while The embodied CO2 emissions in processing ocean exports increased by 50.1%. From 2007 to 2017, The decrease in carbon emission intensity was The major driving factor of The downturn in export-embodied CO2 emissions across The total ocean economy and for seven ocean subsectors (60%), while The export-scale effect primarily drove The increases in CO2 emissions. Moreover, There were disparities in The driving factors behind changes in embodied CO2 emissions between processing and non-processing ocean exports. Based on our findings, we proposed three recommendations from a trade perspective to facilitate low-carbon sustainable transition of China's ocean economy, thus better fulfilling Sustainable Development Goal 14.

We have had a lot of marine accidents that involved failure of the hull structures. Whether it was a crack in the midship region, or a total split-off of the hull girder, or failures due to propagation of cracks, the crux of the matter boils down to a handful of causes that are of great concern to ship designers and operators. Mostly, crack propagation takes place due to fatigue, which is not something this article is about. This article gives an insight into the causes that lead to the failure of the hull girder from a longitudinal strength point of view. And before we start, we have to ask ourselves a few questions. Why have ships split-off? Why have many hull structures split-off after grounding? Why are midships highly prone to such failures? Is it because of a design flaw? Or for that matter, a glitch in the operation standards that have not been maintained?

We have had a lot of marine accidents that involved failure of the hull structures. Whether it was a crack in the midship region, or a total split-off of the hull girder, or failures due to propagation of cracks, the crux of the matter boils down to a handful of causes that are of great concern to ship designers and operators. Mostly, crack propagation takes place due to fatigue, which is not something this article is about. This article gives an insight into the causes that lead to the failure of the hull girder from a longitudinal strength point of view. And before we start, we have to ask ourselves a few questions. Why have ships split-off? Why have many hull structures split-off after grounding? Why are midships highly prone to such failures? Is it because of a design flaw? Or for that matter, a glitch in the operation standards that have not been maintained?

The just-published 2015-2016 Cruise Industry News Annual Report declared MSC Cruises The number one cruise line in Europe, including in The Mediterranean. The Report, which is one of The most reputable sources of information for The industry, stated that MSC Cruises conquered The leading rank in The industry thanks to a deployed capacity across The Continent of about 1.1 million passengers.

The just-published 2015-2016 Cruise Industry News Annual Report declared MSC Cruises The number one cruise line in Europe, including in The Mediterranean. The Report, which is one of The most reputable sources of information for The industry, stated that MSC Cruises conquered The leading rank in The industry thanks to a deployed capacity across The Continent of about 1.1 million passengers.

Vessel strike is recognized as a major modern threat to the recovery of large whale populations globally, but the issue is notoriously difficult to assess. Vessel strikes by large ships frequently go unnoticed, and those involving smaller vessels are rarely reported. Interpreting global patterns of vessel strikes is further hindered by underlying reporting biases caused by differences in countries' research efforts, legislation, reporting structures and enforcement. This leaves global strike data "patchy" and typically scarce outside of developed countries, where resources are more limited. To explore this we investigated vessel strikes with large whales in the Eastern Tropical Pacific (ETP), a coastal region of ten developing countries where heavy shipping and high cetacean densities overlap. Although this is characteristic of vessel strike "hotspots" worldwide, only 11 ETP strike reports from just four countries (∼2% of total reports) existed in the International Whaling Commission's Global Ship Strike Database (2010). This contrasts greatly with abundant reports from the neighboring state of California (United States), and the greater United States/Canadian west coast, making it a compelling case study for investigating underreporting. By reviewing online media databases and articles, peer review publications and requesting information from government agencies, scientists, and tourism companies, we compiled a regional ETP vessel strike database. We found over three times as many strike reports (n = 40), from twice as many countries (n = 8), identifying the geographic extent and severity of the threat, although likely still underestimating the true number of strikes. Reports were found from 1905 until 2017, showing that strikes are a regional, historic, and present threat to large whales. the humpback whale (Megaptera novaeangliae) was the most commonly hit species, and whale-watch industries involving small vessels in areas of high whale densities were recogniz

The COVID-19 pandemic and its lock-down measures have resulted in periods of reduced human activity, known as anthropause. While this period was expected to be favorable for The marine ecosystem, due to a probable reduction of pollution, shipping traffic, industrial activity and fishing pressure, negative counterparts such as reduced fisheries surveillance could counterbalance These positive effects. Simultaneously, on-land pressure due to human disturbance and tourism should have drastically decreased, potentially benefiting land-breeding marine animals such as seabirds. We analyzed 11 breeding seasons of data on several biological parameters of little penguins from a popular tourist attraction at Phillip Island, Australia. We investigated The impact of anthropogenic activities on penguin behavior during The breeding season measured by (1) distribution at sea, (2) colony attendance, (3) isotopic niche (4) chick meal mass, and (5) offspring investment against shipping traffic and number of tourists. The 2020 lock-downs resulted in a near absence of tourists visiting The Penguin Parade®, which was oTherwise visited by 800,000+ visitors on average per breeding season. However, our long-term analysis showed no effect of The presence of visitors on little penguins' activities. Surprisingly, The anthropause did not trigger any changes in maritime traffic intensity and distribution in The region. We found inter- and intra-annual variations for most parameters, we detected a negative effect of marine traffic on The foraging efficiency. Our results suggest that environmental variations have a greater influence on The breeding behavior of little penguins compared to short-term anthropause events. Our long-term dataset was key to test wheTher changes in anthropogenic activities affected The wildlife during The COVID-19 pandemic.