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Following the X-Press Pearl maritime disaster off the coast of Sri Lanka, a stranded spinner dolphin (Stenella longirostris) was recovered, and the cause of death was investigated. Post-mortem examinations revealed evidence of by-catch, but a natural coinfection with dolphin morbillivirus (DMV) and gammaherpesvirus was detected by further analyses, marking the first documented case of a dual viral infection in this species within the region. Molecular diagnostics, including PCR and sequencing, were performed on tissue imprints collected on FTA® cards, confirming the presence of DMV in the prescapular lymph node and gammaherpesvirus in the lesions in the oral cavity. The concurrent detection of DMV and gammaherpesvirus raises significant concerns regarding the potential impacts of environmental stressors, such as chemical pollutants from the X-Press Pearl maritime disaster, on exacerbating susceptibility to viral infections in marine mammals. These findings highlight the need for ongoing surveillance of cetacean populations in the Indian Ocean to better understand pathogen circulation and health and conservation implications of anthropogenic activities on the marine ecosystem. [ABSTRACT FROM AUTHOR]

Simple Summary: Brucella ceti is a marine bacterium that causes neurological, reproductive and skeletal disease in free-ranging cetaceans. Its zoonotic potential and importance for wild animals has prompted, over the years, the search for a reliable diagnostic method to detect antibodies and infer the level of infection. In this work, we perform an exploratory serological study on cetaceans stranded in the Northwestern Mediterranean Sea. Antibody levels were higher in animals with confirmed Brucella disease and infection in juveniles and in animals with chronic morbilliviral infection. This provides the first seroprevalence estimation in this area and reaffirms the active circulation of Brucella in wild cetaceans. Neurobrucellosis in cetaceans, caused by Brucella ceti, is a relevant cause of death in striped dolphins (Stenella coeruleoalba) from the Mediterranean Sea. Serological tests are not used as a routinary technique for the diagnosis of this infection. We briefly describe the pathological findings of nine free-ranging stranded cetaceans diagnosed with Brucella disease or infection in our veterinary necropsy service from 2012 to 2022. The findings included focal diskospondylitis and non-suppurative meningitis, choroiditis and radiculitis. Additionally, an exploratory serological study was conducted in sixty-six frozen sera collected in the period 2012–2022 from fifty-seven striped dolphins, five Risso's dolphins (Grampus griseus), two common bottlenose dolphins (Tursiops truncatus), one common dolphin (Delphinus delphis) and one pilot whale (Globicephala melas) to compare antibody levels in Brucella-infected (n = 8) and non-infected (n = 58) animals, classified by the cause of death, sex, age class and cetacean morbillivirus (CeMV) infection status. The authors hypothesized that active infection in cases of neurobrucellosis would elicit a stronger, detectable humoral response compared to subclinical infections. We performed a commercial competition ELISA (cELISA) using serial serum dilutions for each sample, considering a percentage of inhibition (PI) of ≥40% as positive. A titer of 1:160 was arbitrarily determined as the seropositivity threshold. Seropositive species included striped dolphins and Risso's dolphins. Seroprevalence was higher in animals with neurobrucellosis (87.5%) compared to the overall seroprevalence (31.8%) and to other causes of death, indicating, likely, a high sensitivity but low specificity for neurobrucellosis. Animals with chronic CeMV seemed to have higher seroprevalences, as well as juveniles, which also had a higher disease prevalence. These results indicate, as in other studies, that antibodies are not decisive against clinical brucellosis, although they may indicate a carrier state, and that CeMV may influence Brucella epidemiology. More research is required to elucidate the epidemiology and pathogenesis and to resolve the complicated host–pathogen interaction in Brucella species. [ABSTRACT FROM AUTHOR]

Simple Summary: This study reviews the development of the cetacean stranding response program in Taiwan from 1994 to 2018, and examines 1320 stranding events involving 1698 animals across at least 27 species. The stranding rates have increased significantly over the years, with a notable rise in annual events from 16 to over 90. Seasonal variation demonstrates higher stranding rates during the northeastern monsoon season. The study highlights the spatial distribution of strandings, with the highest frequency in northern Taiwan and mass strandings predominantly in the southwest. Additionally, live strandings accounted for 29.5% of events and 38.9% of animals. The rescue and rehabilitation of some individuals have been conducted, and 15 individuals have been released since 2000. The findings underscore the diversity and stranding patterns of cetaceans around Taiwanese waters, and provide valuable information for developing conservation strategies in the western Pacific. A national cetacean stranding response program in Taiwan has evolved significantly in the past three decades. Initially co-ordinated by National Taiwan University from 1994, the program transitioned to the Taiwan Cetacean Society in 1999, and local governments took on a more prominent role after 2009. A comprehensive stranding database (1994–2018) has been maintained, which documented 1320 stranding events involving 1698 animals from at least 27 species. The most commonly stranded species include finless porpoises, bottlenose dolphins, Kogia spp., and Risso's dolphins. The stranding rates varied annually and seasonally, with increases noted from an average of 16 events per year for the first 3 years to 44–58 events per year between 1997 and 2015, and a sharp rise to over 90 events per year for the period of the last three years. Seasonal variations were also significant, with higher stranding rates during the northeastern monsoon (NEM, October to next April) than that during southwestern monsoon (SWM, May to September). From the aspect of distribution, more frequent and even strandings occurred along the coast of northern Taiwan, while mass strandings were concentrated in the southwestern counties during NEM. Among all strandings, 390 events (29.5%) and 660 animals (38.9%) were live ones. Under great effort in rescuing and rehabilitating 52 cases, 15 cetacean individuals have been released since 2000. Additionally, there have been 56 mass strandings involving at least 11 species since 1994, predominated by pygmy killer whales, particularly during the NEM season along the southwest coast. This study not only contributes to our understanding of the stranding patterns and diversity of the cetaceans in Taiwan, but also provides valuable insights for future conservation strategies on cetaceans in the western Pacific. [ABSTRACT FROM AUTHOR]

Harbour porpoises (Phocoena phocoena) are the only cetacean residents found year-round in Swedish waters and they are exposed to numerous natural and anthropogenic threats. Since the in situ monitoring of cetaceans can be difficult, invasive and often expensive, investigation of stranding patterns and examination of stranded animals can be used as a cost-effective source of data to study these elusive animals. The aim of this study was to investigate the spatiotemporal patterns of harbour porpoise stranding reports and the possible underlying causes in Swedish waters over a ten-year period (2014–2023). Additionally, the Swedish stranding network plays a key role in the collection of stranded carcasses for health and disease surveillance, and geographic coverage of the network also was analysed. When making spatial comparisons, the ten-year period was divided into two five-year blocks. Data on 854 stranded harbour porpoises were analysed from the coasts of the Skagerrak, Kattegat, and Baltic Seas. Both significant spatial and temporal patterns could be identified. Strandings peaked in July through September and hotspots occurred along most of the Swedish west coast, with the most frequent hotspots located around Öresund and especially the area around the Kullen peninsula. The spatial patterns of strandings found in this study are consistent with data on porpoise abundance, prey abundance, and gillnet fisheries' efforts. The latter is known to be one of the primary causes of porpoise mortality. Furthermore, the coverage of the Swedish stranding network increased between the two periods, likely reflecting an increased awareness of the carcass-based surveillance program, and gaps requiring network expansion efforts were identified. These results also provide baseline data to enable the continued monitoring of stranding trends, as changes may indicate changes in population distribution, size or mortality rates. [ABSTRACT FROM AUTHOR]

Simple Summary: The East Asian finless porpoise is a common whale along Chinese coasts. The coast of the Shandong Peninsula is a substantial habitat for the species. However, there is relatively insufficient knowledge of and protection measures for the species population in this region. Based on public literature, media, and internet social websites, we collected and analyzed over two hundred reports on the stranding and accidental catching of finless porpoises along the coast of the Shandong Peninsula from 2000 to 2018. We found that bycatch and stranding incidents occurred widely across the peninsula throughout all seasons. The extensive use of fishing gear was the principal cause of porpoise mortalities and injuries along Shandong Peninsula. We recommend a comprehensive network consisting of an incident reporting system, fishing gear regulations, and scientific monitoring plans to protect the cetacean species in this region. The Shandong Peninsula is located on the western coast of the Pacific and is adjacent to the Bohai Sea (BS) and the Yellow Sea (YS) to the east. The East Asian finless porpoise Neophocaena asiaeorientalis sunameri, a subspecies of the narrow-ridged finless porpoise N. asiaeorientalis, is the dominant cetacean resident along the Shandong Peninsula. However, there is insufficient monitoring data to determine the status of the cetacean species in this region. Based on the publicly available literature, media, and internet social website, this study investigated the spatial–temporal distribution of porpoise stranding and bycatch along the coast of the Shandong Peninsula. Data on over five hundred porpoises from two hundred reports between 2000 and 2018 were compiled and analyzed. Results showed that the bycatch and stranding of porpoises occurred widely across the peninsula throughout all months and increased rapidly between 2010 and 2017. The incidents were more frequent in the area where the BS and YS converged during the spring and early summer than in other seasons. The mean body length of bycaught porpoises was smaller than that of those found stranded. Fishing activities could be the principal cause of local finless porpoise incidents. However, limited data hindered a quantitative evaluation of the living conditions of finless porpoises in this area. Establishing a comprehensive monitoring system, which includes standardized reporting, rescue operations, and scientific research, is essential to finless porpoise protection along the Shandong Peninsula. [ABSTRACT FROM AUTHOR]

Southeast Asia is the world's most polluted area in terms of marine plastics. The Mekong River is one of the largest rivers in the area, and ranked as somewhere between the 8th- and 11th-biggest contributor to plastics in the world's oceans. Here, we investigate how microplastics drift from the Mekong river to Southeast Asia, and which coastlines are most exposed. We identify potential factors (wind drift, rivers, vertical mixing and sinking rates) that affect plastic drift in the region using the OpenDrift model with realistic wind and ocean currents for simulations between three months (summer and winter) and 15 months. We find that the seasonal drift is influenced by the monsoon systems and that most of the plastics strand in the Philippines and Indonesia. In addition, the role of wind drift is significant in strong winds. Vertical mixing and sinking rates are unknowns that affect the relative importance of wind drift (near the surface) and ocean currents. Simulations with different terminal velocities show that, unsurprisingly, the higher the terminal velocities are, the closer they deposit to the source. In light of the large uncertainties in sinking rates, we find that the plastic distribution has large uncertainties, but is clearly seasonal and influenced by wind, vertical mixing, river discharge and sinking rates. The Philippines and Indonesia are found to have the coastlines that are most exposed to plastic pollution from the Mekong river. This study shows that simulations of marine plastic drift are very variable, depending on many factors and assumptions. However, it provides more detailed information on marine plastic pollution in Southeast Asia, and hopefully helps authorities take more practical actions. [ABSTRACT FROM AUTHOR]

Simple Summary: We investigated the causative mechanism of the first mesopelagic fish strandings along the southeast shore of Gran Canaria Island (Canary Islands) during June 2021. We examined remote sensor data (current velocity, Trade Winds, and the presence of upwelling filaments and eddies near the island) to determine the reasons for the strandings. The biological data collected was appropriate for external morphological identification and otolith analysis. In summary, the stranding of mesopelagic fishes was dominated mainly by Diaphus dumerilli, although the otolith analysis revealed the presence of other Myctophidae species. Stranding events are common and appear to be related to mesoscale oceanographic structures. A monitoring program of coastal sites in combination with satellite-derived environmental data will help to gather robust information for modeling when and where such events might occur and what species are associated with these processes. Most mesopelagic fishes perform large diel vertical migrations from the deep-sea zone to the surface. Although there is a trade-off between a higher food availability at the upper layers and an energy cost and predation risk, incursion towards the surface also implies a transport by currents, where the fish are exposed to a stranding risk on the coast. Here, we reported the first documented stranding of mesopelagic fishes along the southeast shore of Gran Canaria Island. Our study hypothesized that (1) the influence of the Canary Current, (2) the dominant incidence of the Trade Winds during summer, and (3) the presence of an upwelling filament coupled with an anticyclonic eddy south of Gran Canaria Island were the causative mechanisms of the strandings. Diaphus dumerilii (Myctophidae family) was the main species found as observed from an external morphological analysis using traditional taxonomy. The otolith contour analysis suggested the presence of other Diaphus spp. and Lobianchia dofleini. Nevertheless, the otolith morphological features described in the literature suggested that all the specimens were actually D. dumerelii. Errors in the identification were mainly due to the high intraspecific variability found in the otolith morphology. Even so, two patterns of oval and elliptic shapes were described with significant differences in its morphometry. [ABSTRACT FROM AUTHOR]

Analyses of the spatial and temporal patterns of 26 years of stranding events (1995–2011 and 2012–2021, n = 568) in Indonesia were conducted to improve the country's stranding response. The Emerging Hot Spot Analysis was used to obtain the spatial and temporal hotspot patterns. A total of 92.4% events were single stranding, while the remaining were of mass stranding events. More stranding events were recorded between 2012 and 2021 in more dispersed locations compared to the previous period. Within the constraints of our sampling limitations, East Kalimantan and Bali were single stranding hotspots and consecutive hotspots. East Java and Sabu-Raijua in East Nusa Tenggara were mass stranding hotspots. Temporally, Raja Ampat (West Papua) experienced a significant increase in case numbers. The presence of active NGOs, individuals or government agencies in some locations might have inflated the numbers of reported cases compared to areas with less active institutions and/or individuals. However, our results still give a good understanding of the progression of Indonesia's stranding responses and good guidance of resource allocation for the stranding network. Several locations in Indonesia that need more efforts (e.g., more training workshops on rescue and necropsies) have been identified in this paper. Suggestions to improve data collection (including georeferencing tips) have also been included. [ABSTRACT FROM AUTHOR]

Simple Summary: We performed a routine necropsy on an adult male pilot whale stranded in a heavy boat traffic area of Denmark. On its outside, there was no visible damage or alterations, and similarly, the internal organs of the thorax and the abdomen also showed no significant changes that could explain the death of the whale. But to our surprise, we found extensive internal injuries after incisions in the head and neck regions: There were multiple fractured bones, muscle trauma and extensive bleeding including a fractured occipital bone with several fragments and bone pieces deeply embedded into the whale brain—injuries that very well, but not with certainty, could be caused by a ship collision. This case demonstrates the importance of performing full necropsies of whales to rule out other causes of death. Otherwise, ship collisions may be an overlooked issue with implications for population health. Necropsy on an adult male pilot whale stranded in Denmark in an area with heavy boat traffic revealed internal lesions in the head and neck region, while the exterior did not show any visible lesions. We found multiple fractured bones, muscle trauma and extensive hemorrhage including a fractured occipital bone with several fragments and bone pieces deeply embedded into the cerebrum of the brain. The brain was literally smashed while the third and partially fourth cervical vertebrae were almost pulverized surrounded by large amounts of blood and muscle contusion. The whale was likely killed due to a ship collision, and this particular case substantiates the value of always performing full necropsies including incisions in head and neck regions on all stranded whales—especially in areas with heavy boat traffic. This case demonstrates the importance of veterinarians performing full necropsies of whales to rule out other causes of death. Otherwise, ship collisions may be an overlooked issue having implications for population health. [ABSTRACT FROM AUTHOR]

Simple Summary: Cetacean strandings occur globally and can impact the welfare as well as the survival of the animals involved. Understanding the welfare status of stranded cetaceans is important to inform appropriate human intervention. However, there is a lack of knowledge on how to assess animal welfare in this context. Here, we used video footage of live stranded animals of four odontocete species to explore which proposed welfare indicators can be assessed at live stranding events. We identified and evaluated potential indicators that could be non-invasively assessed, including 10 non-behavioural and 2 composite behavioural indicators (category of many behaviours). The first data on the fine-scale behaviour of stranded odontocetes and associated human intervention during stranding responses are presented. Our findings suggest that remote assessments of stranded cetacean's welfare states are feasible. These data provide the foundation to develop a systematic, structured welfare assessment framework specific to stranded cetaceans that can inform conservation and management decisions. Despite the known benefit of considering welfare within wildlife conservation and management, there remains a lack of data to inform such evaluations. To assess animal welfare, relevant information must be captured scientifically and systematically. A key first step is identifying potential indicators of welfare and the practicality of their measurement. We assessed the feasibility of evaluating potential welfare indicators from opportunistically gathered video footage of four stranded odontocete species (n = 53) at 14 stranding events around New Zealand. The first stranded cetacean ethogram was compiled, including 30 different behaviours, 20 of which were observed in all four species. Additionally, thirteen types of human intervention were classified. A subset of 49 live stranded long-finned pilot whales (Globicephala melas edwardii) were assessed to determine indicator prevalence and to quantify behaviours. Four 'welfare status' and six 'welfare alerting' non-behavioural indicators could be consistently evaluated from the footage. Additionally, two composite behavioural indicators were feasible. Three human intervention types (present, watering, and touching) and five animal behaviours (tail flutter, dorsal fin flutter, head lift, tail lift, and head side-to-side) were prevalent (>40% of individuals). Our study highlights the potential for non-invasive, remote assessments via video footage and represents an initial step towards developing a systematic, holistic welfare assessment framework for stranded cetaceans. [ABSTRACT FROM AUTHOR]

The causes of marine mammals stranding on coastal beaches are not well understood, but may relate to topography, currents, wind, water temperature, disease, toxic algal blooms, and anthropogenic activity. Offshore earthquakes are a source of intense sound and disturbance and could be a contributing factor to stranding probability. We tested the hypothesis that the probability of marine mammal stranding events on the coasts of Washington and Oregon, USA is increased by the occurrence of offshore earthquakes in the nearby Cascadia subduction zone. The analysis carried out here indicated that earthquakes are at most, a very minor predictor of either single, or large (six or more animals) stranding events, at least for the study period and location. We also tested whether earthquakes inhibit stranding and again, there was no link. Although we did not find a substantial association of earthquakes with strandings in this study, it is likely that there are many factors influencing stranding of marine mammals and a single cause is unlikely to be responsible. Analysis of a subset of data for which detailed descriptions were available showed that most live stranded animals were pups, calves, or juveniles, and in the case of dead stranded mammals, the commonest cause of death was trauma, disease, and emaciation. [ABSTRACT FROM AUTHOR]

Simple Summary: Most whale biologists spend their careers in boats, getting a glimpse at whales only when they come up to the surface to breathe or occasionally to feed. Being able to walk right up to a whale, and even look inside its body, offers scientists and stranding network volunteers a rare and meaningful opportunity to learn from whales at close range. On 14 March 2021, a female adult humpback whale was found dead on a beach near Sitka, Alaska. A team of volunteers performed a necropsy, meaning they dissected the whale to gather information about its cause of death and collected samples for further research (NOAA Fisheries permit 18786-01). Before, during and after the necropsy, the whale was three-dimensionally (3D) scanned using a drone and an iPad. These scans were annotated and arranged into a free publicallyavailable resource known as the 4D virtual necropsy (with time as the 4th dimension). After one month, we documented broad interest in this resource from researchers, educators, community members, and volunteers who respond to marine mammal strandings. We believe 3D scanning of future stranded animals will be useful for a wide range of applications. Stranded large whales represent an opportunity to learn about the anatomy and health of these cryptic free-ranging animals. However, where time and access is frequently limited, law enforcement and management priorities often take precedence over research, outreach, and educational uses. On 14 March 2021, a dead female adult humpback whale was reported stranded on an uninhabited island 15 miles west of Sitka, Alaska. The whale was three-dimensionally scanned using light detection and ranging (LiDAR) and photogrammetry before, during, and at multiple time points after a necropsy, including full decomposition 17 days later (NOAA Fisheries permit 18786-01). These scans were organized and displayed on the site Sketchfab with annotations and made publically available as a "4D virtual necropsy" (the fourth dimension is time). After one month, our user survey indicated widespread interest in the platform by both the local community and worldwide by stranding professionals, researchers, and educators. We are unaware of another 3D scan involving a large whale with soft tissue for teaching, research, or public display, despite the ease of 3D scanning with current technologies and the wide-ranging applications. [ABSTRACT FROM AUTHOR]

The MV Ever Given's stranding in the Suez Canal in March 2021 prompted renewed awareness of the heightened risk of marine accidents in narrow channels as global shipping companies continuously expand vessel sizes. However, there has been limited consideration of ways to improve accident response, and little analysis of future-oriented liabilities and damage compensation schemes for similar maritime accidents. First, key issues related to the Suez Canal stranding accident were analyzed based on web crawling using the R studio program (Version: R-4.0.5) to extract text data from unstructured format text (HTML tags). We designed the research questions to address the key issues/disputes, such as definitions of legal terms related to the Ever Given's stranding accident and the declaration of a general average (G/A), liability for maintaining seaworthiness, source of command authority over the captain, and liability for compensation for delay in delivery. Then, the liability of stakeholders was legally interpreted through causal inductive reasoning based on relevant legal theories and precedents. To help secure safe and sustainable shipping routes, this study demystifies the problems resulting from the side effects of the trend of ultra-large vessels based on technology bias, and will contribute to responses to similar accidents in the future. [ABSTRACT FROM AUTHOR]

Extreme, short-duration fluctuations caused by hydropeaking occurs when hydropower is regulated to cover demand peaks in the electricity market. Such rapid dewatering processes may have a high impact on the downstream biological conditions, particularly related to stranding of fish and other species. The present work analyzes these fluctuations using a two-dimensional unsteady hydraulic modelling approach for quantification of two important hydro-morphological factors on fish stranding risk: the variation in wetted area and the dewatering ramping rate. This approach was applied on the two-kilometer-long reach of Storåne downstream of the Hol 1 power plant, where topo bathymetric LiDAR (Light Detection and Ranging) data was available providing a high-resolution digital elevation model. Based on this model, hydraulic conditions could be simulated in high detail allowing for an accurate assessment of the hydro morphological factors. Results show the dried area distribution at different flows and dewatering ramping rates. The attenuation of the water level fluctuation due to the damping effect along the river reach controls the dewatering rate. We recommend an alternative scenario operation which can reduce the impact of the peaking operation and estimate the operational mitigation cost. We find that the modelling based on the fine resolution grid provides new opportunities in assessing effects of hydropower regulations on the ecosystem. [ABSTRACT FROM AUTHOR]