To see the other types of publications on this topic, follow the link: Stranding network.
Journal articles on the topic 'Stranding network'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Stranding network.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Norman, S. A., C. E. Bowlby, M. S. Brancato, et al. "Cetacean strandings in Oregon and Washington between 1930 and 2002." J. Cetacean Res. Manage. 6, no. 1 (2023): 87–99. http://dx.doi.org/10.47536/jcrm.v6i1.795.
Full textAbstract:
The Northwest Region (NWR) Marine Mammal Stranding Network was created in the early 1980s to provide a consistent framework in which to collect and compile data about marine mammal strandings in Oregon and Washington. The NWR includes the nearshore waters and 4,243km (2,632 n.miles) of coastline. For the years 1930-2002, there were 904 stranding events, representing 951 individual animals and 23 species: 4 species of balaenopterids, 1 eschrichtiid, 2 physeterids, 4 ziphiids, 10 delphinids and 2 phocoenids. Gender was determined for 343 males and 266 females. Only one mass stranding was recorded (sperm whales: 1979). A few species comprised the majority (71%) of stranding events in the NWR: harbour porpoise (34%), gray whales (23%), Dall’s porpoise (12%) and Pacific white-sided dolphins (4%). There was a steep increase (511%) in the number of stranding reports beginning in the 1980s with over 86% of all records occurring during the last two decades (1980s and 1990s). The general trend of increased reported strandings during the last two decades corresponds to the formation of a formal stranding network and a heightened interest and dedication by the public and government agencies in reporting and documenting strandings. For all events combined, the primary stranding peak was April-July. Since stranding recoveries depend heavily on reports from the general public, most stranding records were in summer when more people are present along the coastline. Individual species or species groups showed varying levels of conformity to this overall seasonal trend. The value and limitations of the use of strandings data in a management context are discussed.
2
Nemiroff, Leah, Tonya Wimmer, Pierre-Yves Daoust, and Donald F. McAlpine. "Cetacean Strandings in the Canadian Maritime Provinces, 1990-2008." Canadian Field-Naturalist 124, no. 1 (2010): 32. http://dx.doi.org/10.22621/cfn.v124i1.1027.
Full textAbstract:
Organized cetacean stranding networks function to respond quickly and efficiently to strandings, to coordinate live releases, to gather and analyze data, and to educate the public. Stranding networks in the three Canadian Maritime provinces (New Brunswick, Nova Scotia, and Prince Edward Island) recently cooperated to form the Marine Animal Response Network. The resulting collaborative database provides an opportunity to assess patterns of cetacean strandings encompassing 19 years (1990-2008 inclusive) from across the region. During this period, a total of 640 stranding events involving 19 species and 881 individuals of both sexes and varying age groups were reported. Stranding events primarily involved single animals, although several mass strandings were recorded, the largest involving 60 Long-finned Pilot Whales (Globicephala melas). The number of strandings was found to vary substantially over time and among the three provinces. In part, this is likely a reflection of differences in local network effort among regions. Most animals were found dead ashore. Entanglement in fishing gear occurred in over 10% of the incidents. Relatively more mysticetes were found dead ashore or at sea and entangled in fishing gear than expected by chance, while more odontocetes were found stranded alive than expected. Harbour Porpoises (Phocoena phocoena) appear to be especially vulnerable to entanglement in fishing gear. Necropsies, performed on a subsample of the stranded animals, suggest that Harbour Porpoises die significantly more often from disease than mishap, while Long-finned Pilot Whales and Atlantic White-sided Dolphins (Lagenorhynchus acutus) suffer equally from mishap and disease. Refloating was attempted for 23% of animals, with an apparent success rate of 83%, although there are no data on long-term survival. Neither sex nor age of the refloated animals was found to be an indicator of subsequent short-term survival.
3
Ulfsson, Vigge, Hyeyoung Kim, Linnea Cervin, Anna Roos, and Aleksija Neimanis. "Investigation of Spatiotemporal Patterns of Harbour Porpoise (Phocoena phocoena) Strandings in Swedish Waters for Improved Monitoring and Management." Oceans 5, no. 2 (2024): 166–80. http://dx.doi.org/10.3390/oceans5020010.
Full textAbstract:
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.
4
Silva, Flávio José de Lima, Simone Almeida Gavilan, Aline da Costa Bomfim, et al. "Insights sobre um encalhe em massa de falsas orcas (Pseudorca Crassidens Owen, 1846)." Natural Resources 12, no. 1 (2022): 45–58. http://dx.doi.org/10.6008/cbpc2237-9290.2022.001.0005.
Full textAbstract:
False killer whales (FKWs; Pseudorca crassidens) are found in deep waters of temperate and tropical oceans worldwide. This species is considered near threatened and global populations’ trends are unknown although there is evidence of decline of various populations. The mass stranding of cetaceans remains an intriguing event and often the cause(s) are unclear or poorly investigated. In Brazil, cetacean mass strandings have been recorded yet they have not been investigated. In this study, we aimed to report the epidemiologic features of a mass stranding event involving 30 live FKWs occurred in northeastern Brazil in 2013. Releasing attempts and posterior monitoring data indicated successful outcome for 24 of 30 FKWs. Postmortem pathologic investigations confirmed live-stranding stress response and intestinal (Bolbosoma sp.) and otic (Stenurus sp.) endoparasitism. Toxicologic analyzes detected high concentrations of total mercury in liver correlating with liver damage, as indicated by elevated transaminases. In this mass stranding, key factors were early notification, organizational and operational framework, trained and sufficient personnel, resources and equipment, government support, and strategy and decision making. These results underscore the benefits of a rapid marine mammal network response, the importance of integrative multidisciplinary investigations, and set baseline information for mass strandings of cetaceans in Brazil.
5
Plön, Stephanie, Stephanie Norman, Pierre-André Adam, et al. "Spatio-temporal trends in cetacean strandings and response in the south-western Indian Ocean: 2000-2020." J. Cetacean Res. Manage. 24, no. 1 (2023): 95–119. http://dx.doi.org/10.47536/jcrm.v24i1.396.
Full textAbstract:
The south-western Indian Ocean (SWIO) is a region of global importance for marine mammal biodiversity, but our understanding of most of the species and populations found there is still rudimentary. The Indian Ocean Network for Cetacean Research (IndoCet) was formed in 2014 and is dedicated to the research of all cetacean species across the SWIO. Since 2019, there have been efforts to create a regional network for coordinated response to stranding events as well as training and capacity building in the SWIO region. The present analysis represents a first investigation of stranding data collected by various members and collaborators within the IndoCet network, covering over 14,800km of coastline belonging to nine countries/territories. Between 2000-2020, there were 397 stranding events, representing 1,232 individual animals, 17 genera and 27 species, belonging to six families: four balaenopterids, one balaenid, one physeterid, two kogiids, six ziphiids and 14 delphinids. Seven mass strandings were recorded: two were composed of three to 20 individuals and five composed of >20 individuals. Spatial analysis of stranding events indicated that local spatio-temporal clusters (excessive number of events in time and geographic space) were present in all countries/territories, except for the Comoros. The only significant cluster was detected on the southwest coast of Mauritius, just west of the village of Souillac. The SWIO region predominantly comprises relatively poor countries/territories, but imminent Blue/Ocean economy developments are prevalent throughout the region. This study highlights the importance of establishing baselines upon which any future potential impact from anthropogenic developments in the region can be measured.
6
Masski, Hicham, and Renaud De Stéphanis. "Cetaceans of the Moroccan coast: information from a reconstructed strandings database." Journal of the Marine Biological Association of the United Kingdom 98, no. 5 (2015): 1029–37. http://dx.doi.org/10.1017/s0025315415001563.
Full textAbstract:
Cetaceans of Morocco have been poorly studied to date, and only sporadic information comes from scientific cruises for this group. In an attempt to learn more on the occurrence, distribution and relative abundances of cetaceans in Morocco, a stranding database was reconstructed from various sources (stranding reports from state agencies and newspaper clippings). This inventory documented 205 cases of stranding between 1980 and 2009. Most of the strandings and most confirmed cases of interactions with human activity (fishing, for dolphins; collisions, for whales) were reported in the Strait of Gibraltar and adjacent areas from the Atlantic and the Mediterranean. Sixteen species were identified from the stranding database, of which seven species were the most abundant. These were striped dolphins, common dolphins, bottlenose dolphins, fin whales, sei whales, sperm whales and long-finned pilot whales. The fin and sei whales were present throughout the year and stranding of common and striped dolphins were minimal between September and December. The fin, sei and sperm whales seem to be present in Moroccan waters at birth and at different stages of their life cycle. Establishing an observation network of sufficient and sustainable density in Morocco is the most likely way to collect robust data for the calculation of credible population indicators for cetaceans. Monitoring will certainly improve through better collaboration among Moroccan institutions and a greater awareness in Moroccan civil society of environmental issues.
7
MATSUISHI, TAKASHI. "Stranding network and its scientific significance." NIPPON SUISAN GAKKAISHI 77, no. 2 (2011): 296–99. http://dx.doi.org/10.2331/suisan.77.296.
Full text
8
Langle-Flores, Alfonso, Zinthia López-Vázquez, Rosa María Chávez Dagostino, and Adriana Aguilar-Rodríguez. "Untangling Humpback Whale-Watching Management Networks: Collaboration and Conflict in the Northeast Pacific." Water 15, no. 22 (2023): 3975. http://dx.doi.org/10.3390/w15223975.
Full textAbstract:
Humpback whales face emerging anthropogenic challenges such as entanglement in abandoned fishing gear and stranding during their winter migration. Such challenges require collective action solutions involving diverse stakeholders across jurisdictions, social sectors, and geographies. Collaborative governance systems involve conflictual and collaborative interactions. We used a quantitative approach (social network analysis) to map the structure of three social networks: Collaboration in disentanglement, collaboration in stranding, and conflict. We administered a face-to-face survey to 38 stakeholders from four social sectors across seven coastal localities from April to November 2021. We also obtained perspectives from the same stakeholders about pressing conflicts, rule compliance, and law enforcement regarding whale-watching management in the region using a semi-structured questionnaire. We found hints of different dimensions of collaboration occurring simultaneously: Coordination, cooperation, and conflict. Networks played distinct roles in promoting collaboration across sectors, and while the disentanglement network coordinated civil society and the public sector, the stranding network facilitated cooperation within the public sector. The most pressing social conflicts detected by stakeholders were pleasure boats, abandoned fishing gear, and poor rule compliance regarding the distance between boats and whales. Our results suggest that in the context of institutional weakness, collaborative social networks play a crucial role in the management and conservation of coastal and marine common-pool resources.
9
Mustika, Putu Liza Kusuma, Kathryn K. High, Mochamad Iqbal Herwata Putra, et al. "When and Where Did They Strand? The Spatio-Temporal Hotspot Patterns of Cetacean Stranding Events in Indonesia." Oceans 3, no. 4 (2022): 509–26. http://dx.doi.org/10.3390/oceans3040034.
Full textAbstract:
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.
10
Sathasivam, Kumaran, and K. S. Natarajan. "Obtaining distributional information on Indian Ocean cetaceans: suggestions based on an Indian network experience." J. Cetacean Res. Manage. 12, no. 2 (2023): 173–75. http://dx.doi.org/10.47536/jcrm.v12i2.574.
Full textAbstract:
The understanding of the occurrence and distribution of cetaceans in the Indian region is largely based on information that has been incidentally obtained from strandings and bycatches. An attempt was made to compile such data systematically. The resultant database has been made widely accessible by hosting it on the internet. To improve the quality of information collected, identification aids were published on the same website. A stranding booklet was also created, mainly for the use of individuals and organisations with limited access to the internet. The ‘spare capacity’ of individuals and organisations was used to gather information and also to prepare the website and booklets, so that little or no expense was incurred. Recommendations are made regarding the collection of distributional data from the Indian Ocean.
11
Englesou, Julia, Mary Lekakou, and Ernest Tzannatos. "The Efficiency of the Greek Lighthouse Network." Journal of Navigation 51, no. 3 (1998): 421–29. http://dx.doi.org/10.1017/s0373463398007930.
Full textAbstract:
Among the many primary causes which lead to a shipping casualty, those of wrecking, stranding or coming into contact with fixed coastal structures depend (although not exclusively and only under specific conditions of visibility) upon the efficiency of the lighthouse and navigating lights network of a national coastline. The analysis of the shipping casualties involving Greek ships in the Greek seas revealed that, despite the recent introduction of sophisticated navigating aids for the prevention of stranding and contact, the share of the corresponding casualties remains unchanged. It appears that for coastal shipping operations, and in particular for port approaches, the traditional light navigating aids are and will always provide an irreplaceable safety service for navigators. This is mainly attributed to their technological simplicity which offers a high level of signal reliability and friendliness for the navigator.
12
McGovern, Barry, Ross M. Culloch, Michael O'Connell, and Simon Berrow. "Temporal and spatial trends in stranding records of cetaceans on the Irish coast, 2002–2014." Journal of the Marine Biological Association of the United Kingdom 98, no. 5 (2016): 977–89. http://dx.doi.org/10.1017/s0025315416001594.
Full textAbstract:
Using Irish strandings data collected between 2002 and 2014, seasonal and annual trends in the number of strandings for all strandings identified to species level (N = 1480), and for the five most frequently reported species: common dolphin (25.7% of records), harbour porpoise (22.2%), long-finned pilot whale (8.8%), striped dolphin (6.9%) and bottlenose dolphin (6.9%) were investigated. With the exception of bottlenose dolphins, there was a significant linear increase in the number of strandings across years for all species and for all strandings collectively, that were identified to species-level. Only common dolphins demonstrated a significant increase in the proportion of records relative to all other strandings, which may be indicative of a real rise in the number of strandings of this species. Common dolphins and harbour porpoises showed a similar significant difference in monthly strandings, with more strandings occurring during the earlier months of the year. Significant differences in the gender of stranded animals were found in common, striped, bottlenose and Atlantic white-sided dolphins and sperm and pygmy sperm whales. Live and mass stranding events were primarily comprised of pelagic species. Most strandings occurred on the south and west coasts, with two hotspots for live and mass strandings identified. The patterns and trends identified are discussed in relation to the caveats in interpreting strandings data. Specifically to Ireland, the findings highlight the urgent need to build on the current volunteer reporting network and augment this comprehensive dataset with post-mortem examinations to better understand the cause of the trends identified. The importance of strandings data in informing conservation and management guidelines of these species’ is discussed.
13
Alfonsi, Eric, Eleonore Méheust, Sandra Fuchs, et al. "The use of DNA barcoding to monitor the marine mammal biodiversity along the French Atlantic coast." ZooKeys 365 (December 30, 2013): 5–24. https://doi.org/10.3897/zookeys.365.5873.
Full textAbstract:
In the last ten years, 14 species of cetaceans and five species of pinnipeds stranded along the Atlantic coast of Brittany in the North West of France. All species included, an average of 150 animals strand each year in this area. Based on reports from the stranding network operating along this coast, the most common stranding events comprise six cetacean species (<i>Delphinus delphis</i>, <i>Tursiops truncatus</i>, <i>Stenella coeruleoalba</i>, <i>Globicephala melas</i>, <i>Grampus griseus</i>, <i>Phocoena phocoena</i>)<i> </i>and one pinniped species (<i>Halichoerus grypus</i>). Rare stranding events include deep-diving or exotic species, such as arctic seals. In this study, our aim was to determine the potential contribution of DNA barcoding to the monitoring of marine mammal biodiversity as performed by the stranding network.We sequenced more than 500 bp of the 5’ end of the mitochondrial <i>cox1</i> gene of 89 animals of 15 different species (12 cetaceans, and three pinnipeds). Except for members of the Delphininae, all species were unambiguously discriminated on the basis of their <i>cox1</i> sequences. We then applied DNA barcoding to identify some “undetermined” samples. With again the exception of the Delphininae, this was successful using the BOLD identification engine. For samples of the Delphininae, we sequenced a portion of the mitochondrial control region (MCR), and using a non-metric multidimentional scaling plot and posterior probability calculations we were able to determine putatively each species. We then showed, in the case of the harbour porpoise, that <i>cox1</i> polymorphisms, although being lower than MCR ones, could also be used to assess intraspecific variability. All these results show that the use of DNA barcoding in conjunction with a stranding network could clearly increase the accuracy of the monitoring of marine mammal biodiversity.
14
Grattarola, Carla, Guido Pietroluongo, Donatella Belluscio, et al. "Pathogen Prevalence in Cetaceans Stranded along the Italian Coastline between 2015 and 2020." Pathogens 13, no. 9 (2024): 762. http://dx.doi.org/10.3390/pathogens13090762.
Full textAbstract:
The monitoring of stranded marine mammals represents a strategic method to assess their health, conservation status, and ecological role in the marine ecosystem. Networks worldwide track stranding events for the passive monitoring of mortality patterns, emerging and reemerging pathogens, climate change, and environmental degradation from a One Health perspective. This study summarizes pathogen prevalence data from the Italian Stranding Network (ISN) derived from post-mortem investigations on cetaceans found dead stranded along the Italian coastline between 2015 and 2020. The decomposition of the carcasses and logistics limited the post-mortem examination to 585 individuals, out of 1236 single-stranding reports. The most relevant pathogens identified were Cetacean Morbillivirus, Herpesvirus, Brucella spp., and Toxoplasma gondii, whose roles as environmental stressors are well known, despite their real impact still needing to be investigated in depth. Statistical analysis showed that age and sex seem to be positively related to the presence of pathogens. This study represents the first step in harmonizing post-mortem investigations, which is crucial for evidence-based conservation efforts. Implementing diagnostic and forensic frameworks could offer an indirect insight into the systematic monitoring of diseases to improve the identification of regional and temporal hotspots in which to target specific mitigation, management, and conservation strategies.
15
Page, Felicia M., James Manning, Lesley Howard, Ryan Healey, and Nancy E. Karraker. "Developing bottom drifters to better understand the stranding locations of cold-stunned sea turtles in Cape Cod Bay, Massachusetts." PeerJ 11 (August 30, 2023): e15866. http://dx.doi.org/10.7717/peerj.15866.
Full textAbstract:
Every fall, juvenile sea turtles in the Northwest Atlantic Ocean are threatened by rapidly declining water temperatures. When sea turtles become hypothermic, or cold-stunned, they lose mobility—either at the surface, subsurface, or the bottom of the water column—and eventually strand at the shoreline where rescue teams associated with the Sea Turtle Stranding and Salvage Network may search for them. Understanding the effects of ocean currents on the potential stranding locations of cold-stunned sea turtles is essential to better understand stranding hotspots and increase the probability of successful discovery and recovery of turtles before they die in the cold temperatures. Traditional oceanographic drifters—instruments used to track currents—have been used to examine relationships between current and stranding locations in Cape Cod Bay, but these drifters are not representative of sea turtle morphology and do not assess how bottom currents affect stranding locations. To address these knowledge gaps, we designed new drifters that represent the shape and dimensions of sea turtles—one that can float at the surface and one that sinks to the bottom—to track both surface and bottom currents in Cape Cod Bay. We found a marked difference between the trajectories of our new drifter models and those that were previously used for similar research. These findings bring us one step closer to identifying the transport pathways for cold-stunned sea turtles and optimizing cold-stunned sea turtle search and rescue efforts in Cape Cod.
16
BOUSLAH, Yahia, Raouf Zaidi, Mohammed Mesaoudi, Karim Maamar, Alae-Eddine Belmahi, and Mohammed Bouderbala. "New occurrence of cetacean stranded on the Algerian West Coast and Associated Threats: (2016-2020)." South Asian Journal of Experimental Biology 12, no. 3 (2022): 357–65. http://dx.doi.org/10.38150/sajeb.12(3).p357-365.
Full textAbstract:
The cetacean populations of the Algerian west coast are monitored in terms of relative abundance, demographic and ecological parameters, and death causes by Environmental Monitoring Network Laboratory team (EMNL) throughout the Algerian west coast. A survey of cetaceans stranded along the Algerian west coast (2016-2020) allowed us to record a total number of 52 stranding events, know the appearance frequency of different species, specify the spatio-temporal distribution, and determine some causes of death. The stranding included 08 species: one species of balaenopteridae, one species of physeteridae, one species of ziphidae, and five species of delphinidae. From the stranding data recorded on the Algerian west coast, we can conclude that there are two frequent species: the Delphinus delphis (31%) and Stenella ceoruleoalba (21%) of all stranded cetaceans, two commun species: Ziphius cavirostris (17%) and Tursiops truncatus (11%), two uncommon species: Grampus griseus (8%) and Globicephala melas (6%), and two rare species: Physeter catodon (4%) and Baleanoptera acutorostrata (2%). Stranding events occurred all the year round with the highest frequency in winter n=19 (36,54%) and less in spring n=16 (30,77%). Following post-mortem necropsies on the dead animals, 51,92% (n=27) of cetaceans stranded on the Algerian west coast presented criteria related directly or probably to interaction with fishing gears and boat collision. The other causes of death were not determined (n=25, or 48,08%). The D. delphis and S. ceouleoalba were more vulnerable to human and fisheries interaction.
17
Podesta, Michela, Angela D'Amico, Gianni Pavan, Aimilia Drougas, Anastasia Komnenou, and Nicola Portunato. "A review of Cuvier’s beaked whale strandings in the Mediterranean Sea." J. Cetacean Res. Manage. 7, no. 3 (2023): 251–61. http://dx.doi.org/10.47536/jcrm.v7i3.735.
Full textAbstract:
Cuvier’s beaked whale (Ziphius cavirostris) is the only species of beaked whale commonly found in the Mediterranean Sea, a deep, semienclosed basin. Beaked whales are generally an offshore family often found in association with the canyons and steep escarpments common to the area. Much of the current knowledge of this species has been derived from strandings data. Historically, strandings data for the Mediterranean Sea has been collected by individual researchers and more recently, over the last two decades, by national strandings networks. We reviewed strandings data collected by strandings networks from Italy, Greece, Spain and France. Additionally, we compiled strandings information gleaned from the literature, personal communications, regional newspapers and the world wide web from countries that border the Mediterranean Sea. While this review is certainly not exhaustive, it has allowed the creation of an extensive geo-referenced basin wide database using a geographic information system (GIS) of over 300 stranding events. The acquired data permit documentation of the number of mass stranding events, allow general observations about distribution and chronology of stranding events dating back to 1803 and enables evaluation of strandings based on several different criteria. The first recorded mass stranding event was in 1963 off Genova, Italy. Analysis shows that specific geographic stranding areas can be identified, even though the level of effort undertaken in the different countries may vary.
18
Dias, Madalena M., and Alkiviades C. Payatakes. "Network models for two-phase flow in porous media Part 2. Motion of oil ganglia." Journal of Fluid Mechanics 164 (March 1986): 337–58. http://dx.doi.org/10.1017/s0022112086002586.
Full textAbstract:
The behaviour of non-wetting ganglia undergoing immiscible displacement in a porous medium is studied with the help of a theoretical simulator. The porous medium is represented by a network of randomly sized unit cells of the constricted-tube type. The fluid of a non-wetting ganglion is in contact with the wetting fluid at menisci which are assumed to be spherical cups. The flow in every constricted unit cell occupied by a single fluid is modelled as flow in a sinusoidal tube. The flow in every unit cell that contains a meniscus and portions of both fluids is treated with a combination of a Washburn-type analysis and a lubrication-theory approximation. The flow problem is thus reduced to a system of linear equations the solution of which gives the instantaneous pressures on the nodes, the flowrates through the unit cells, and the velocities of the menisci. The motion of a ganglion is determined by assuming quasi-static flow, taking a small time increment, updating the positions of the menisci, and iterating. The behaviour of solitary ganglia is studied under conditions of quasi-static displacement (Ca slightly larger than critical), as well as dynamic displacement (Ca substantially larger than critical). Shape evolution, rate of flow, mode of break-up, and stranding are examined. The stranding and break-up coefficients are determined as functions of the capillary number and the ganglion size for a 100 × 200 sandpack. The dependence of the average ganglion velocity on ganglion size, capillary number, viscosity ratio and dynamic contact angle is examined for the simple case of motion between straight rows of spheres. It is found, among other things, that when μo < μw the velocity of ganglia can be substantially larger than that of the displacing fluid.
19
Liao, Shiguan, Jinxian Weng, Zhaomin Zhang, Zhuang Li, and Fang Li. "Probabilistic Modeling of Maritime Accident Scenarios Leveraging Bayesian Network Techniques." Journal of Marine Science and Engineering 11, no. 8 (2023): 1513. http://dx.doi.org/10.3390/jmse11081513.
Full textAbstract:
This paper introduces a scenario evolution model for maritime accidents, wherein Bayesian networks (BNs) were employed to predict the most probable causes of distinct types of maritime incidents. The BN nodes encompass factors such as accident type, life loss contingency, accident severity, quarter and time period of the accident, and type and gross tonnage of the involved ships. An analysis of 5660 global maritime accidents spanning the years 2005 to 2020 was conducted. Using Netica software, a tree augmented network (TAN) model was constructed, thus accounting for interdependencies among risk-influencing factors. To confirm these results, a validation process involving sensitivity analysis and historical accident records was performed. Following this, both forward causal inference and reverse diagnostic inference were carried out on each node variable to scrutinize the accident development trend and evolution process under preset conditions. The findings suggest that the model was competent in effectively predicting the likelihood of various accident scenarios under specific conditions, as well as extrapolating accident consequences. Forward causal reasoning unveiled that general cargo ships with a gross tonnage of 1–18,500 t were most prone to experiencing collision and stranding/grounding accidents in the first quarter. Reverse diagnostic reasoning indicated that, in the early morning hours, container ships, general cargo ships, and chemical ships with a tonnage of 1–18,500 t were less likely to involve life loss in the event of collision accidents.
20
Rojo-Nieto, E., P. D. Álvarez-Díaz, E. Morote, et al. "Strandings of cetaceans and sea turtles in the Alboran Sea and Strait of Gibraltar: a long–time glimpse of the north coast (Spain) and the south coast (Morocco)." Animal Biodiversity and Conservation 34, no. 1 (2011): 151–63. http://dx.doi.org/10.32800/abc.2011.34.0151.
Full textAbstract:
A total of 13 species of cetaceans and three species of marine turtles were found in this study. Data were collected by eight independent and self-regulated stranding networks, providing information about 1,198 marine mammal (10 odontocetii, three mysticetii and one phocidae) and 574 sea turtle stranding events between 1991 and 2008. Trends in the strandings were analysed in relation to species composition and abundance, and their geographic and seasonal distribution. The most abundant species recorded were the striped dolphin and the loggerhead turtle. Some of the strandings, such as the humpback whale, harbour porpoise, hooded seal and olive ridley turtle, were considered ‘rare’ because their distribution did not match the pattern of the study. When the north and south coasts in the study area were compared, pilot whales stranded more frequently in the north, while delphinid species stranded more in the south coast, and loggerhead turtles stranded more frequently in the north while leatherback turtles stranded more in south coast.
21
Bao, Kexin, Jinqiang Bi, Ruixin Ma, Yue Sun, Wenjia Zhang, and Yongchao Wang. "A Spatial-Reduction Attention-Based BiGRU Network for Water Level Prediction." Water 15, no. 7 (2023): 1306. http://dx.doi.org/10.3390/w15071306.
Full textAbstract:
According to the statistics of ship traffic accidents on inland waterways, potential safety hazards such as stranding, hitting rocks, and suspending navigation are on the increase because of the sudden rise and fall of the water level, which may result in fatalities, environmental devastation, and massive economic losses. In view of this situation, the purpose of this paper is to propose a high-accuracy water-level-prediction model based on the combination of the spatial-reduction attention and bidirectional gate recurrent unit (SRA-BiGRU), which provides support for ensuring the safe navigation of ships, guiding the reasonable stowage of ships, and flood prevention. The first contribution of this model is that it makes use of its strong fitting ability to capture nonlinear characteristics, and it fully considers the time series of water-level data. Secondly, the bidirectional recurrent neural network structure makes full use of past and future water-level information in the mapping process between input and output sequences. Thirdly, and most importantly, the introduction of spatial-reduction attention on the basis of BiGRU can not only automatically capture the correlations between the hidden vectors generated by BiGRU to address the issue of precision degradation due to the extended time span in water-level-forecasting tasks but can also make full use of the spatial information between water-level stations by emphasizing the influence of significant features on the prediction results. It is noteworthy that comparative experiments gradually prove the superiority of GRU, bidirectional recurrent neural network structure, and spatial-reduction attention, demonstrating that SRA-BiGRU is a water-level-prediction model with high availability, high accuracy, and high robustness.
22
Liu, Shaoyong, Jian Deng, and Cheng Xie. "A Framework for Risk Evolution Path Forecasting Model of Maritime Traffic Accidents Based on Link Prediction." Journal of Marine Science and Engineering 13, no. 6 (2025): 1060. https://doi.org/10.3390/jmse13061060.
Full textAbstract:
Water transportation is a critical component of the overall transportation system. However, the gradual increase in traffic density has led to a corresponding rise in accident occurrences. This study proposes a quantitative framework for analyzing the evolutionary paths of maritime traffic accident risks by integrating complex network theory and link prediction methods. First, 371 maritime accident investigation reports were analyzed to identify the underlying risk factors associated with such incidents. A risk evolution network model was then constructed, within which the importance of each risk factor node was evaluated. Subsequently, several node similarity indices based on node importance were proposed. The performance of these indices was compared, and the optimal indicator was selected. This indicator was then integrated into the risk evolution network model to assess the interdependence between risk factors and accident types, ultimately identifying the most probable evolution paths from various risk factors to specific accident outcomes. The results show that the risk evolution path shows obvious characteristics: “lookout negligence” is highly correlated with collision accidents; “improper route selection” plays a critical role in the risk evolution of grounding and stranding incidents; “improper on-duty” is closely linked to sinking accidents; and “illegal operation” show a strong association with fire and explosion events. Additionally, the average risk evolution paths for collisions, groundings, and sinking accidents are relatively short, suggesting higher frequencies of occurrence for these accident types. This research provides crucial insights for managing water transportation systems and offers practical guidance for accident prevention and mitigation.
23
Houser, D., K. Moore, S. Sharp, J. Hoppe, and J. Finneran. "Cetacean evoked potential audiometry by stranding networks enables more rapid accumulation of hearing information in stranded odontocetes." J. Cetacean Res. Manage. 18, no. 1 (2023): 93–101. http://dx.doi.org/10.47536/jcrm.v18i1.436.
Full textAbstract:
Knowing the hearing range and sensitivity of a marine mammal is fundamental to determining its potential for being impacted by ocean noise. Enabling stranding responders to perform hearing tests on stranded odontocetes is the most likely means by which most odontocete species will be tested and by which population-level variability in hearing will be determined. A portable auditory evoked potential (AEP) system was modified for use by stranding response teams and optimised to test odontocete hearing. Stranding responders were trained on the system and deployed it to strandings from 2010–2013. Eighteen partial or complete audiograms from common dolphins (n = 15) and Atlantic white-sided dolphins (n = 3) were obtained. Both species demonstrated typically delphinid audiograms with upper frequency limits of hearing between 113–160kHz; however, the region of best sensitivity in the Atlantic white-sided dolphin (28–56kHz) was 18–28 dB less sensitive than that of the common dolphin. A single common dolphin presented with severe hearing loss consistent with presbycusis in delphinids, but with undefined etiology. The number of audiograms obtained during the study greatly increases our knowledge about hearing in these species, neither of which are common to managed care facilities. In the case of the common dolphin, the number of animals tested allows a first estimate of population-level variability. Continued use of AEP systems by stranding responders will expedite the collection of audiometric information for previously untested species and permit sufficient sample sizes to determine population-level variability in the hearing of tested species.
24
Aniceto, A. S., L. Tassara, A. Rikardsen, and P. Blévin. "Mass strandings of seven toothed and baleen whale species in Northern Norway in March 2020 call for further investigation." Polar Biology 44, no. 7 (2021): 1457–61. http://dx.doi.org/10.1007/s00300-021-02869-6.
Full textAbstract:
AbstractMonitoring whale strandings are a key aspect of ecosystem management as stranded animals can provide indications on ecosystem health, pollution and adverse effects due to anthropogenic activities. Most mass mortality events are reported for toothed whales and rarely involve baleen whales. In the course of one month in spring 2020, 17 whales belonging to seven different species, stranded on the shores of Northern Norway, above the Arctic circle. This multi-species event included humpback (Megaptera novaeangliae), fin (Balaenoptera physalus) and sperm whales (Physeter macrocephalus), that were accompanied by northern bottlenose whales (Hyperoodon ampullatus), a white-beaked dolphin (Lagenorhynchus albirostris), a long-finned pilot whale (Globicephala melas) and a harbour porpoise (Phocoena phocoena). We discuss some potential causes of death based on the previous literature and available information for the area, highlighting the need for further investigation on cetacean strandings at high latitudes. Ultimately, the reasons for the stranding could only be identified by a thorough examination of all the animals, which was unfortunately not conducted. As the threats to polar ecosystems and access to local shores are likely to increase, reports of cetacean mortality are also expected to surge, particularly in high latitude regions where climate variations and anthropogenic activities are increasing. This study makes recommendations for future steps and considerations for monitoring networks and standardized sampling methods for future marine mammal stranding events. Finally, we suggest that national and international efforts based on the collaborative relationships are implemented, considering the multiple facets of animal ecology and health as an achievable step in the near future.
25
Morris, Sinead E., Jonathan L. Zelner, Deborah A. Fauquier, et al. "Partially observed epidemics in wildlife hosts: modelling an outbreak of dolphin morbillivirus in the northwestern Atlantic, June 2013–2014." Journal of The Royal Society Interface 12, no. 112 (2015): 20150676. http://dx.doi.org/10.1098/rsif.2015.0676.
Full textAbstract:
Morbilliviruses cause major mortality in marine mammals, but the dynamics of transmission and persistence are ill understood compared to terrestrial counterparts such as measles; this is especially true for epidemics in cetaceans. However, the recent outbreak of dolphin morbillivirus in the northwestern Atlantic Ocean can provide new insights into the epidemiology and spatio-temporal spread of this pathogen. To deal with uncertainties surrounding the ecology of this system (only stranded animals were observed), we develop a statistical framework that can extract key information about the underlying transmission process given only sparse data. Our self-exciting Poisson process model suggests that individuals are infectious for at most 24 days and can transfer infection up to two latitude degrees (220 km) within this time. In addition, the effective reproduction number is generally below one, but reaches 2.6 during a period of heightened stranding numbers near Virginia Beach, Virginia, in summer 2013. Network analysis suggests local movements dominate spatial spread, with seasonal migration facilitating wider dissemination along the coast. Finally, a low virus transmission rate or high levels of pre-existing immunity can explain the lack of viral spread into the Gulf of Mexico. More generally, our approach illustrates novel methodologies for analysing very indirectly observed epidemics.
26
Torres-Pereira, Andreia, Hélder Araújo, Silvia Silva Monteiro, et al. "Assessment of Harbour Porpoise Bycatch along the Portuguese and Galician Coast: Insights from Strandings over Two Decades." Animals 13, no. 16 (2023): 2632. http://dx.doi.org/10.3390/ani13162632.
Full textAbstract:
The Iberian harbour porpoise population is small and fisheries bycatch has been described as one of its most important threats. Data on harbour porpoise strandings collected by the Portuguese and Galician stranding networks between 2000 and 2020 are indicative of a recent mortality increase in the western Iberian coast (particularly in northern Portugal). Overall, in Portugal and Galicia, individuals stranded due to confirmed fishery interaction represented 46.98% of all analysed porpoises, and individuals stranded due to probable fishery interaction represented another 10.99% of all analysed porpoises. Considering the Portuguese annual abundance estimates available between 2011 and 2015, it was possible to calculate that an annual average of 207 individuals was removed from the population in Portuguese waters alone, which largely surpasses the potential biological removal (PBR) estimates (22 porpoises, CI: 12–43) for the same period. These results are conservative and bycatch values from strandings are likely underestimated. A structured action plan accounting for new activities at sea is needed to limit the Iberian porpoise population decline. Meanwhile, there is an urgent need for a fishing effort reorganization to directly decrease porpoise mortality.
27
Gutiérrez-Estrada, Juan Carlos, Inmaculada Pulido-Calvo, Antonio Peregrín, et al. "Integrating local environmental data and information from non-driven citizen science to estimate jellyfish abundance in Costa del Sol (southern Spain)." Estuarine, Coastal and Shelf Science 249 (February 5, 2021): 107112. https://doi.org/10.1016/j.ecss.2020.107112.
Full textAbstract:
<strong>El copyright de esta publicación pertenece al editor en exclusiva, no está permitido el acceso al texto completo</strong> <strong><em>The copyright of this publication belongs exclusively to the publisher, access to the full text is not allowed</em></strong> Tourism, fishing and aquaculture are key economic sectors of Costa del Sol (southern Iberian Peninsula). The management of these activities is sometimes disturbed by the onshore arrival and stranding of jellyfish swarms. In the absence data on the occurrence of these organisms, it may be interesting to explore data from non-driven systems, such as social networks. The present study show how data in text format from a mobile app called Infomedusa can be processed and used to model the relationship between estimated abundance of jellyfish on the beaches and local environmental conditions. The data retrieved from this app using artificial intelligence procedures (transition network or TN algorithm), were used as input for GAM models to estimate the abundance of jellyfish based on wind speed and direction. The analysis of data provided by Infomedusa indicated that only 30.39% of messages provided by the users had information about absence/presence of jellyfishes in the beaches. On the other hand, the TN processing capacity showed an accuracy level to discriminate messages with information on absence/presence of jellyfish slightly higher than 80%. GAM models considering the wind direction and speed of previous day explained between 37% and 77% of the variance of jellyfish abundance estimate from Infomedusa data. In conclusion, this approach may contribute to the development of a system for predicting the onshore arrival of jellyfish in the Costa del Sol.
28
Gomes-Pereira, J. N., R. Prieto, V. Neves, et al. "The role of Malcolm Clarke (1930–2013) in the Azores as a scientist and educationist." Journal of the Marine Biological Association of the United Kingdom 97, no. 4 (2014): 821–28. http://dx.doi.org/10.1017/s0025315414000794.
Full textAbstract:
Malcolm Roy Clarke (1930–2013) was a British teuthologist who made an important contribution to marine science in the Azores archipelago (Portugal). Malcolm started doing research in the Azores from 1980s onward, settling for residency in 2000 after retirement (in 1987). He kept publishing on Azorean cephalopods collaborating in 20% of the peer reviewed works focusing on two main areas: dietary studies; and the ecology of cephalopods on seamounts. Since his first visit in 1981, he was involved in the description of the dietary ecology of several cetaceans, seabirds, and large pelagic and deep-water fish. Using his own data, Malcolm revised the association of cephalopods with seamounts, updating and enlarging the different cephalopod groups according to species behaviour and ecology. Malcolm taught several students working in the Azores on cephalopods and beak identification, lecturing the Third International Workshop in Faial (2007). He empowered the recently established research community, by providing important contacts with foreign institutes and informal advice. He collaborated in the regional cetacean stranding network (RACA) and was an active member of the advisory board of the journal Arquipelago—Life and Marine Sciences. But the scientific role of Malcolm Clarke in the Azores went beyond his academic activities. In the last 10 years Malcolm and Dot Clarke dedicated themselves to building and running a museum on Pico Island, showing the biology of the sperm whale and its interaction with squid; a cultural and touristic legacy for future generations to enjoy.
29
Long, Brett, Chip Arnold, Carrie Goertz, and Lee Majors. "Mobile Treatment and Rehabilitation Enclosure (MTRE) for small pinnipeds." International Oil Spill Conference Proceedings 2014, no. 1 (2014): 300054. http://dx.doi.org/10.7901/2169-3358-2014-1-300054.1.
Full textAbstract:
The North Slope of Alaska is a demanding and harsh environment. Being prepared for an oil spill involving wildlife in this region requires training, innovation, and partnerships. For the past three years animal care groups, industry oil spill response organizations, and federal agencies have been collaborating to prepare for such an event. Protocol development is an essential and initial process to accomplish response goals. In 2011, protocols were developed for the care of oiled affected phocid seals in Alaska, focusing on the need for remote, deployable operations in the arctic. While developing these protocols, authors drew from their experiences caring for pinnipeds at their facility as well as from involvement in the statewide marine mammal stranding network. As the only institution authorized to rehabilitate stranded marine mammals in Alaska, we are uniquely positioned to assist in mitigating risks associated with possible oil exposure to these animals. Finding resources to treat oiled wildlife is a challenge on the North Slope, especially for medium to long term care. With that in mind, we designed and developed a Mobile Treatment and Rehabilitation Enclosure (MTRE). This deployable enclosure and pool with a life support system meets Animal Welfare Act holding specifications for small pinnipeds including harbor seals, spotted seals, ringed seals, and ribbon seals. The enclosure is designed to be assembled by 2 to 4 individuals and ready for use within 12 hours. While it is purpose built for small pinnipeds it would also be appropriate for short term, triage care of other marine mammals such as walrus calves, polar bear cubs, and sea otters. As a test of our oiled pinniped protocols and the MTRE this system was deployed during the mutual aid drill on the North Slope in August of 2013.
30
Gross, Stephanie, Marco Roller, Holger Haslob, et al. "Spatiotemporal accumulation of fatal pharyngeal entrapment of flatfish in harbour porpoises (Phocoena phocoena) in the German North Sea." PeerJ 8 (October 20, 2020): e10160. http://dx.doi.org/10.7717/peerj.10160.
Full textAbstract:
The evolution of a permanent separation of the upper respiratory and digestive tract is one of the adaptions cetaceans evolved for their aquatic life. Generally, it prevents odontocetes from choking on either saltwater or foreign bodies during ingestion under water. Nevertheless, several sporadic single case reports from different parts of the world show that this separation can be reversed especially by overly large items of prey. This incident can have a fatal outcome for the odontocetes. The German federal state of Schleswig-Holstein has a year-round, permanent and systematic stranding network that retrieves stranded marine mammals from its shorelines and constantly enables post-mortem examinations. In 2016, with nine affected animals, a high incidence of fatal pharyngeal entrapment of flatfish in harbour porpoises (Phocoena phocoena) occurred during spring and early summer on the German North Sea island of Sylt. All flatfish were identified as common sole (Solea solea). A retrospective post-mortem data analysis over a 30-year period from the North and Baltic Sea revealed similar yearly and seasonally case accumulations on the same island in the 1990s as well as several single case events over the whole timespan. All cases except one were caused by flatfish. When flatfish speciation was performed, only common sole was identified. From 1990 to 2019, of all examined harbour porpoises, 0.3% (2/713) from the Baltic Sea and 5.5% (45/820) from the North Sea died due to fish entrapped in the pharynx. On the North Sea coast, the occurrence of fatal obstruction shows high yearly variations from 0 to 33.3%. Years that stand out are especially 1990 to 1992, 1995, as well as 2016. The majority of all cases generally occurred between April and July, indicating also a seasonality of cases. This study evaluates the occurrence of fatal pharyngeal entrapment of fish in two geographically separated harbour porpoise populations. Additionally, common sole is clearly identified as a potentially risky item of prey for these small odontocetes.
31
Laval, Marine, Abdelbadie Belmouhcine, Luc Courtrai, et al. "Detection of Sargassum from Sentinel Satellite Sensors Using Deep Learning Approach." Remote Sensing 15, no. 4 (2023): 1104. http://dx.doi.org/10.3390/rs15041104.
Full textAbstract:
Since 2011, the proliferation of brown macro-algae of the genus Sargassum has considerably increased in the North Tropical Atlantic Sea, all the way from the Gulf of Guinea to the Caribbean Sea and the Gulf of Mexico. The large amount of Sargassum aggregations in that area cause major beaching events, which have a significant impact on the local economy and the environment and are starting to present a real threat to public health. In such a context, it is crucial to collect spatial and temporal data of Sargassum aggregations to understand their dynamics and predict stranding. Lately, indexes based on satellite imagery such as the Maximum Chlorophyll Index (MCI) or the Alternative Floating Algae Index (AFAI), have been developed and used to detect these Sargassum aggregations. However, their accuracy is questionable as they tend to detect various non-Sargassum features. To overcome false positive detection biases encountered by the index-thresholding methods, we developed two new deep learning models specific for Sargassum detection based on an encoder–decoder convolutional neural network (CNN). One was tuned to spectral bands from the multispectral instrument (MSI) onboard Sentinel-2 satellites and the other to the Ocean and Land Colour Instrument (OLCI) onboard Sentinel-3 satellites. This specific new approach outperformed previous generalist deep learning models, such as ErisNet, UNet, and SegNet, in the detection of Sargassum from satellite images with the same training, with an F1-score of 0.88 using MSI images, and 0.76 using OLCI images. Indeed, the proposed CNN considered neighbor pixels, unlike ErisNet, and had fewer reduction levels than UNet and SegNet, allowing filiform objects such as Sargassum aggregations to be detected. Using both spectral and spatial features, it also yielded a better detection performance compared to algal index-based techniques. The CNN method proposed here recognizes new small aggregations that were previously undetected, provides more complete structures, and has a lower false-positive detection rate.
32
Li, Qiyue, Wenya Li, Geying Lai, et al. "Identifying High Stranding Risk Areas of the Yangtze Finless Porpoise via Remote Sensing and Hydrodynamic Modeling." Remote Sensing 14, no. 10 (2022): 2455. http://dx.doi.org/10.3390/rs14102455.
Full textAbstract:
Freshwater cetaceans that inhabit river basins with seasonally changing hydrological regimes have a higher risk of stranding, leading to increased mortality and population decline. In Poyang Lake, the stranding risk of the critically endangered Yangtze finless porpoise are high, due to the significant differences in hydrological and landscape conditions between the flood and dry seasons. However, this stranding information is not well recorded, resulting in poorly guided investigation and rescue efforts. We here employ remote sensing and hydrodynamic modeling to obtain four evaluation indicators in dry, normal, and flood scenarios in Poyang Lake. Results show that nearly 50% of the largest habitat range of the porpoises in the flood season will be land areas during the dry season, and that landscape fragmentation between land and water has increased over the past three decades. In all scenarios, the mean water depth of the habitat varied from 1.77 to 4.89 m from September–February. In the dry scenario, about 59% of the habitat experiences a water depth of <1 m within 15 days. The high stranding risk area is 284.54 km2 in the dry scenario, >251.04 km2 in the normal scenario, and >90.12 km2 in the flood scenario. High-stranding risk areas are located within city boundaries, where porpoise stranding cases have been recorded, especially in Duchang, which has the most high-risk areas in all scenarios. In all scenarios, the high stranding risk area has an average bathymetry of 7.81 m and an average water depth between 1.75 and 5.54 m. Our results can guide future investigations to establish sound stranding networks, and the methods proposed here are also applicable to studies of other freshwater cetaceans facing severe stranding risk.
33
Ziccardi, Michael, Sarah Wilkin, and Teresa Rowles. "Modification of NOAA's National Guidelines for Oiled Marine Mammal Response as a Consequence of the Macondo/Deepwater Horizon Oil Spill." International Oil Spill Conference Proceedings 2014, no. 1 (2014): 986–97. http://dx.doi.org/10.7901/2169-3358-2014.1.986.
Full textAbstract:
ABSTRACT The Macondo/Deepwater Horizon response was the United States' first Spill of National Significance and, as such, had significant challenges over a “normal” oil spill response effort. One complex issue in this response was the potential for a large numbers of cetaceans (dolphins and whales), manatees, and sea turtles to be impacted by the oil, as these animals were abundant in the area of oil and at great risk because of their life history, including large amounts of time spent at the surface. To address this risk and provide for response for these species, the Marine Mammal and Sea Turtle (MMST) Group within the Wildlife Branch officially became operational on April 30, 2010, enhancing the operations of the pre-existing marine mammal and sea turtle stranding response network in the northern Gulf of Mexico. Throughout the response, the Group used previously-developed National Guidelines for Oiled Marine Mammal Response, drafted in 2005, to help focus animal collection and care activities in the field as well as within established facilities and to direct collection of samples and data for assessment of the impacts of the spill, with potential use by resource trustees in criminal and civil litigation. While having pre-existing, reviewed and approved protocols to refer to greatly improved response efficiency, significant gaps became apparent in this protocol document due to the challenges associated with coordination across such a complex response and the lack of previous knowledge on how oil can affect the species impacted. Since the conclusion of the MMST effort, NOAA and associated experts have revised and updated this document to institute a more robust command-and-control system within the Wildlife Branch, to better delineate roles and responsibilities for personnel involved in future oiled marine mammal responses, and to provide more detailed information to allow local regions to better prepare for recovering and caring for pinnipeds and cetaceans should they be affected. This paper will detail these changes to this aspect of the Wildlife Branch, and provide attendees a better appreciation for what readiness and training marine mammal responders will be striving towards for future responses.
34
Houser, Dorian S., Kathleen Moore, Sarah Sharp, and James J. Finneran. "Rapid acquisition of marine mammal evoked potential audiograms by stranding networks." Journal of the Acoustical Society of America 128, no. 4 (2010): 2299. http://dx.doi.org/10.1121/1.3508077.
Full text
35
Siebert, Ursula, Jan Lakemeyer, Martin Runge, et al. "Investigations on the Health Status and Infection Risk of Harbour Seals (Phoca vitulina) from Waters of the Lower Saxon Wadden Sea, Germany." Animals 14, no. 20 (2024): 2920. http://dx.doi.org/10.3390/ani14202920.
Full textAbstract:
Harbour seals (Phoca vitulina) are the most common pinniped species in the Wadden Sea of Schleswig-Holstein, Hamburg and Lower Saxony, Germany. Their numbers have recovered after significant depletion due to viral outbreaks and effects of anthropogenic activities like pollution and habitat disturbance. Within the Wadden Sea National Park of Lower Saxony the harbour seal is protected. As a top predator in the Wadden Sea ecosystem, the harbour seal is a sentinel species for the state of the environment. Between 2015 and 2017, a total of 80 stranded dead harbour seals were collected along the coastline of Lower Saxony and submitted for pathological investigations. Of these, 70 seals were born in the same year (0–7 months, age group 1) and eight in the previous year (8–19 months, age group 2), due to high mortality rates in these age groups. However, two perennial animals were also available for examination during this period, one of which was in good nutritional condition. Many of the seals that had been mercy-killed and found dead were in poor nutritional status. Histopathological, microbiological, parasitological and virological examinations were conducted on 69 individuals (86% (69/80)) in a suitable state of preservation. Respiratory tract parasitosis, cachexia, and bronchopneumonia were the most common causes of death or disease. Overall, there was no evidence of a relapse of a viral disease outbreak. Macrowaste, such as plastic waste or fishery-related debris, were not found in any gastrointestinal tract of the animals examined. There was also no evidence of grey seal predation. Weakness and cachexia were prominent causes of disease and death in harbour seals found within a few weeks after birth, but bronchopneumonia and septicaemia also developed in slightly older animals. Frequently found microbial pathogens in seals from Lower Saxony were similar to those found in other studies on seals from the Wadden Sea region in Schleswig-Holstein, for example streptococci and Escherichia coli/v. haemolytica, Brucella spp. and Erysipelothrix rhusiopathiae, potentially human pathogenic germs. The results of the examinations of dead harbour seals from Lower Saxony show that pathological investigations on a representative number of animals deliver urgently needed information on the health status of the population. The results represent an important contribution to the state of the top predators of the Wadden Sea as part of the obligations within the Trilateral Wadden Sea Agreement, Oslo and Paris Convention for the Protection of the Marine Environment of the North-East Atlantic (OSPAR) and the Marine Framework Directive. The investigations should be continued as a matter of urgency and the stranding network should be expanded.
36
Dickson, Liam C. D., Stuart R. B. Negus, Christophe Eizaguirre, Kostas A. Katselidis, and Gail Schofield. "Aerial Drone Surveys Reveal the Efficacy of a Protected Area Network for Marine Megafauna and the Value of Sea Turtles as Umbrella Species." Drones 6, no. 10 (2022): 291. http://dx.doi.org/10.3390/drones6100291.
Full textAbstract:
Quantifying the capacity of protected area networks to shield multiple marine megafauna with diverse life histories is complicated, as many species are wide-ranging, requiring varied monitoring approaches. Yet, such information is needed to identify and assess the potential use of umbrella species and to plan how best to enhance conservation strategies. Here, we evaluated the effectiveness of part of the European Natura 2000 protected area network (western Greece) for marine megafauna and whether loggerhead sea turtles are viable umbrella species in this coastal region. We systematically surveyed inside and outside coastal marine protected areas (MPAs) at a regional scale using aerial drones (18,505 animal records) and combined them with distribution data from published datasets (tracking, sightings, strandings) of sea turtles, elasmobranchs, cetaceans and pinnipeds. MPAs covered 56% of the surveyed coastline (~1500 km). There was just a 22% overlap in the distributions of the four groups from aerial drone and other datasets, demonstrating the value of combining different approaches to improve records of coastal area use for effective management. All four taxonomic groups were more likely to be detected inside coastal MPAs than outside, confirming sufficient habitat diversity despite varied life history traits. Coastal habitats frequented by loggerhead turtles during breeding/non-breeding periods combined overlapped with 76% of areas used by the other three groups, supporting their potential use as an umbrella species. In conclusion, this study showed that aerial drones can be readily combined with other monitoring approaches in coastal areas to enhance the management of marine megafauna in protected area networks and to identify the efficacy of umbrella species.
37
Davison, NJ, MP Dagleish, EJ Dale, et al. "First confirmed reports of the isolation of Brucella ceti from a Risso’s dolphin Grampus griseus and a killer whale Orcinus orca." Diseases of Aquatic Organisms 145 (July 15, 2021): 191–95. http://dx.doi.org/10.3354/dao03612.
Full textAbstract:
Brucella ceti has been recovered from a number species of cetaceans worldwide over the last 25 yr. Here we report, for the first time, the recovery of B. ceti from a Risso’s dolphin Grampus griseus and a killer whale Orcinus orca. Recovery from an abdominal mass in the dolphin provides further evidence of the systemic pathogenic potential for B. ceti infection in cetaceans. The isolation of B. ceti ST23 (porpoise cluster) from a killer whale from a group known to eat other marine mammals raises the possibility of infection via ingestion. This report takes the number of cetacean species in UK coastal waters from which B. ceti has been isolated to 11 and highlights the value of routine, comprehensive and specific screening for significant pathogens such as Brucella sp. by strandings networks.
38
Evatt, G. W., A. R. D. Smedley, K. H. Joy, et al. "The spatial flux of Earth’s meteorite falls found via Antarctic data." Geology 48, no. 7 (2020): 683–87. http://dx.doi.org/10.1130/g46733.1.
Full textAbstract:
Abstract Contemporary calculations for the flux of extraterrestrial material falling to the Earth’s surface (each event referred to as a “fall”) rely upon either short-duration fireball monitoring networks or spatially limited ground-based meteorite searches. To date, making accurate fall flux estimates from the much-documented meteorite stranding zones of Antarctica has been prohibited due to complicating glacial ice dynamics and difficulties in pairing together distinct meteorite samples originating from the same fall. Through glaciological analysis and use of meteorite collection data, we demonstrate how to overcome these barriers to making flux estimates. Furthermore, by showing that a clear latitudinal variation in fall frequencies exists and then modeling its mathematical form, we are able to expand our Antarctic result to a global setting. In this way, we hereby provide the most accurate contemporary fall flux estimates for anywhere on Earth. Inverting the methodology provides a valuable tool for planning new meteorite collection missions to unvisited regions of Antarctica. Our modeling also enables a reassessment of the risk to Earth from larger meteoroid impacts—now 12% higher at the equator and 27% lower at the poles than if the flux were globally uniform.
39
Siebert, Ursula, Frances Gulland, Timm Harder, et al. "Epizootics in harbour seals (Phoca vitulina): clinical aspects." NAMMCO Scientific Publications 8 (September 1, 2010): 265. http://dx.doi.org/10.7557/3.2689.
Full textAbstract:
Epizootic diseases causing considerable mortality in harbour seal populations have mainly been reported from the waters of the United States and Europe. Such die-offs were largely attributable to viral infections. Several hundred individuals died from respiratory infections caused by Influenza A viruses at the coast of New England, USA, in 1979, 1980 and 1982. More than 53,000 harbour seals were killed in European waters by Phocine Distemper Virus (PDV), a morbillivirus,in two outbreaks in 1988 and 2002. For several other epizootics of smaller scale in the waters of the Atlantic and Pacific coast of the USA and, most recently, in Danish and Swedish waters in 2007 the causes remain unclear, although characteristic respiratory symptoms and interstitial pneumonia suspicious of viral etiology were detected as well as occasionally bacterial infections caused by Erysipelothrix rhusiopathiae and Pseudomonas aeruginosa. Mass mortalities caused by biotoxins, direct human interactions or changes in oceanographic conditions have so far not been described for harbour seals. However, high organochlorine loads detected in European harbour seal populations and suspected to impede immune functions, were considered an aggravating factor in the 1988 morbillivirus epizootic. Establishing supranational stranding networks is a key prerequisite for the detection of future unusual die-offs in marine mammals. Detailed post-mortem investigations of all organ systems are essential for targeted etiological studies towards the causes of mass mortalities in seals.
40
Schuler, Krysten L., Bridget B. Baker, Karl A. Mayer, et al. "Refining Aging Criteria for Northern Sea Otters in Washington State." Journal of Fish and Wildlife Management 9, no. 1 (2018): 208–21. http://dx.doi.org/10.3996/052017-jfwm-040.
Full textAbstract:
Abstract Measurement of skull ossification patterns is a standard method for aging various mammalian species and has been used to age sea otters Enhydra lutris from Russia, California, and Alaska. Cementum annuli counts have also been verified as an accurate aging method for sea otters in Alaska. In this study, we compared cementum annuli count results and skull ossification patterns as methods for aging the northern sea otter, E. l. kenyoni, in Washington State. We found significant agreement between the two methods, suggesting that either method could be used to age sea otters in Washington. We found that ossification of the squamosal–jugal suture at the ventral glenoid fossa can be used to differentiate male subadults from adults. To assist field biologists or others without access to cementum annuli or skull ossification analysis techniques, we analyzed a suite of morphologic, physiologic, and developmental characteristics to assess whether a set of these more easily accessible parameters could also predict age class. We identified tooth condition score, evidence of reproductive activity in females, and tooth eruption pattern as the most useful criteria for classifying sea otters in Washington. We created a simple decision tree based on characteristics accessible in the field or at necropsy, which can be used to reliably predict age class of Washington sea otters as determined by cementum annuli. These techniques offer field biologists and marine mammal stranding networks a replicable, cost-conscious methodology to gather useful biological information from sea otters.
41
Chen, Chunfeng, Changyu Hu, and Jianjiang Zhou. "A Fast Power Lines RCS Calculation Method Combining IEDG with CM-SMWA." Electronics 12, no. 3 (2023): 757. http://dx.doi.org/10.3390/electronics12030757.
Full textAbstract:
The existing methods for calculating electromagnetic scattering can be used to obtain the RCS of power lines. However, these methods do not take advantage of the periodicity of power lines. We propose a fast electromagnetic scattering calculation method combining the integral equation discontinuous Galerkin (IEDG) method and the characteristic modes-Sherman–Morrison–Woodbury algorithm (CM-SMWA) exploiting the power lines with stranded structure. We adopt the IEDG to discretize the electric field integral equation (EFIE) so that the EFIE can deal with non-conformal grids and significantly increase the flexibility of the CM-SMWA. Combing with the periodic property of power lines, the modeling and grid generation shall be carried out within one cycle (stranding) of the power line, and the grids of the rest cycle of the power line can be spliced by translating the grid of the divided sections. The advantage of the proposed method lies in that only the CM of one segment needs to be calculated, and the result can be applied to other segments to avoid repeated calculation of the CMs. The simulation results of the RCS of power lines show that the calculation time of our method is cut down by 50% as compared to the conventional CM-SMWA.
42
Bolaños-Jiménez, Jaime, Jeremy J. Kiszka, Laurent Bouveret, et al. "The Killer Whale in the Caribbean Sea: An Updated Review of Its Ecology, Exploitation, and Interactions with Fisheries." Aquatic Mammals 49, no. 2 (2023): 184–94. http://dx.doi.org/10.1578/am.49.2.2023.184.
Full textAbstract:
The killer whale (Orcinus orca) is a cosmopolitan cetacean distributed worldwide. Extensive studies have described its ecology and behavior across multiple polar and temperate regions. On the other hand, there is limited information on the distribution, ecological roles, and abundance of killer whales in tropical and subtropical regions. Herein, we build on previous work to update information on the spatiotemporal distribution, exploitation, and natural history of killer whales in the Caribbean Sea. We also document new records on their interaction with other species and human activities. We collated 385 records from the literature, online biodiversity information systems, the Internet (social networks and video-hosting websites), and citizen science-based initiatives. Records included sightings (87.3%), intentional captures (10.6%), bycatch (0.3%), and strandings (1.8%). Data primarily originated from research projects/activities (57%) and citizen science-based initiatives (43%). Records were distributed in the eastern Caribbean (39.5%), the southern Caribbean (19.7%), the Greater Antilles (19.2%), the Bahamian Region (13.0%), Central America (6.8%), and eastern Florida (1.8%). Killer whales were recorded year-round, but most data were reported between March and August (59.6%). The scarcity of records in Central America could reflect true lower densities in the region, lower observation effort, or a combination of the two. Because of the paucity of data, this study supports the growing importance of citizen-science initiatives to document the occurrence and ecology of this species in the Caribbean. Our dataset also confirms the occasional and widespread occurrence of killer whales throughout the Caribbean Sea. Potential low densities and limited predictability of their occurrence hinder dedicated research on this species.
43
Palacios, Daniel M., Cristiane C. A. Martins, and Carlos Olavarría. "Aquatic mammal science in Latin America: a bibliometric analysis for the first eight years of the Latin American Journal of Aquatic Mammals (2002-2010)." Latin American Journal of Aquatic Mammals 9, no. 2 (2014): 42–64. http://dx.doi.org/10.5597/lajam00174.
Full textAbstract:
We conducted a meta-analysis of the publication statistics for Vols. 1-8 of the Latin American Journal of Aquatic Mammals (LAJAM), the joint scholarly publication of the Sociedad Latinoamericana de Especialistas en Mamíferos Acuáticos and the Sociedad Mexicana de Mastozoología Marina, with the following purposes: (a) identifying the main patterns in the authorship and content published between 2002 and 2010, and (b) assessing the contributions of these scientific societies in the Latin American and global contexts. With the caveat that the results are only representative of the researchers that chose to publish in LAJAM during the period covered by the study, the metadata from 168 articles indicated that most of the research was conducted on small odontocetes (Sotalia, Pontoporia, Tursiops) and pinnipeds (Arctocephalus, Otaria, Mirounga) of coastal habits. Rorqual whales (Balaenoptera, Megaptera) and oceanic odontocetes (Stenella, Mesoplodon, Orcinus, Delphinus) also were well represented. Studies of distribution (including first records) were the most common, followed by those related to feeding, strandings, health and bycatch. Seventeen countries were represented in the primary affiliation of the lead author, but just five dominated the contribution: Brazil (52%), Argentina (10%), México (7%), Uruguay (5%) and USA (5%). Among institution types, a university was reported as the primary affiliation type by 50% of the authors, while 26% reported a NGO, 17% a government agency and 7% another type of organization. A social network analysis of 404 authors identified a large, well-connected cluster of 263 authors. Within this cluster, 13 authors from Brazil, Perú, Argentina and Colombia were among the most collaborative. The female to male ratio was 1:1.6 among lead authors and 1:3.2 among lead authors that published more than one article, suggesting a gender disparity within this scientific community. According to Google Scholar™, 91 articles in LAJAM were cited in other publications through January 2012, with an average of 7.5 citations per article. The 15 most cited articles had between 13 and 15 citations, were predominantly from Brazil, and were mainly about small cetaceans.
44
Yuan, Jing, Yili Gao, Nan Wang, Tianhua Jiang, and Zhaolong Cheng. "Cetacean stranding records along the Shanghai–Zhejiang coastline in China: implications for distribution and conservation." Frontiers in Marine Science 11 (January 10, 2025). https://doi.org/10.3389/fmars.2024.1483805.
Full textAbstract:
Cetacean ecology has been poorly studied in the Shanghai-Zhejiang waters of East China Sea, seriously hindering appropriate local conservation practices. Here stranding records from 1953 to 2023 around the Shanghai-Zhejiang waters were collated from literature, media, and social websites to clarify species composition and spatio-temporal variations of cetacean strandings. A total of 138 stranding records involving 197 individuals across 23 species were identified, comprising four Mysticeti and Odontoceti species. Cetacean stranding records occurred extensively along the Shanghai-Zhejiang coastline throughout the year and have grown swiftly since the 2000s. Narrow-ridged finless porpoise Neophocaena asiaeorientalis and common minke whale Balaenoptera acutorostrata were the most frequently stranded species. Over 84% of the stranding events involved only a single individual. Melon-headed whale Peponocephala electra predominated in mass stranding incidents. Spatially, the stranding reports showed a significant cluttering distribution pattern. Clustering of cetacean records occurred in the Yangtze River estuary, downstream region of Qiantang River, southeastern of Ningbo, and Oujiang River estuary. Seasonal analysis showed increased cetacean stranding events in spring, yet without a significant difference. Post-mortem examinations of stranded individuals showed that coastal fisheries and port activities were probably the dominant causes of local cetacean strandings. Standardizing cetacean stranding records, strengthening fisheries regulations, and rescue training programs are recommended to establish a dedicated cetacean stranding monitoring network, which is vital for cetacean conservation in this region.
45
Prajapati, Shakti. "Stranding cases of endangered Ganges river dolphins in the Ghaghara–Sharada irrigation canals, Ganges river basin, India: conservation implications." Mammalia, August 25, 2020. http://dx.doi.org/10.1515/mammalia-2019-0110.
Full textAbstract:
AbstractPopulations of endangered Ganges and Indus river dolphins have been under severe threat from diversion of river water by dams, barrages, and canal networks across the Indus and Ganges–Brahmaputra river basins. River dolphins prefer deep water and might enter irrigation canals in the dry-season, getting stranded there. Stranding can cause mortality and local population declines, and poses an emerging challenge to river dolphin conservation efforts. In Pakistan’s Indus river basin, stranding rates of Indus dolphins in irrigation canals are high, and well-coordinated rescue-release operations are undertaken. Despite commendable river dolphin rescue efforts in some parts of India, stranding cases are not always reported. From open-access media reports (2007–08 to 2017–18), I found 26 stranding cases of Ganges river dolphins from the Ghaghara–Sharada canal network across seven districts of Uttar Pradesh, India. Of these, 62% reports were from 2015 to 2016. Most cases occurred in secondary and tertiary canal branches. Interviews with fishers, farmers, and government officials revealed low awareness of stranding cases. Stranded dolphins might have no chance of returning to their source habitat, unless rescued. From my results, I discuss how current barrage-canal operations could influence dolphin stranding risk, and their implications for flow management in the Ghaghara–Sharada river basin.
46
Galves, Jamal, Celeshia Guy Galves, Nicole Auil Gomez, et al. "Analysis of a long-term dataset of Antillean manatee strandings in Belize: implications for conservation." Oryx, June 13, 2022, 1–9. http://dx.doi.org/10.1017/s0030605321000983.
Full textAbstract:
Abstract We analysed 23 years of data on strandings of the Antillean manatee Trichechus manatus manatus in Belize, documented by the Belize Marine Mammal Stranding Network, to examine the threats to this population. A total of 451 stranding incidents were reported, of which 376 (83.4%) cases were verified. A total of 286 (63.4%) of the incidents occurred within Belize District, where the number of strandings has almost tripled since 2009. Watercraft collisions accounted for the highest number of strandings, with 131 confirmed cases, and is the leading cause of anthropogenic mortality for this population. Collision with watercraft is an emerging and major threat to manatees in Belize, and is correlated with increases in human activity, in particular associated with tourism. This finding of high levels of manatee deaths in Belize is consistent with trends previously reported for manatees in Florida and Puerto Rico. This work can provide guidance to detect and address similar patterns of mortality in other Antillean manatee populations across the species' range. There is a need for greater awareness of the threats facing the species and its habitat, for stakeholder partnerships to address these threats, implementation of legislation for the protection of manatees, and consistent enforcement of regulations to protect this population. Boating regulations, such as no-wake zones within areas of high manatee presence, as well as regulation of tourism boating activities, need to be implemented to reduce the threats to the species.
47
Arévalo-González, Gloria Katerin, Lesly Cabrias-Contreras, Andrea Venturotti N. Carneiro, et al. "Stranding reports of the Antillean manatee in the middle Magdalena Basin, Colombia 2011 to 2023." Latin American Journal of Aquatic Mammals, April 16, 2024. http://dx.doi.org/10.5597/lajam00330.
Full textAbstract:
The aim of this study was to conduct an analysis of reported events concerning Antillean manatee (Trichechus manatus manatus) strandings in the middle Magdalena Basin region of Colombia from January 2011 to December 2023. To achieve this, a literature search was conducted in newspapers, news broadcasts, as well as gray and published reports, complemented by interviews and workshops with various governmental and non-governmental organizations. This search resulted in reliable information regarding past experiences involving stranded manatees over the years. Cases attended to by the environmental authority and its partners were also considered. Forty-four stranding events were recorded, with 34 deaths and 10 live manatees. Of the cases discovered, 79.5% of the reported cases were addressed. This effort highlighted the current lack of an official database that would provide firsthand knowledge of Antillean manatee stranding events in Colombia, thereby hindering timely and appropriate territorial management during response to the challenges faced by this species in the region. Furthermore, it underscores the need to implement a standardized response pathway for manatee cases, following appropriate protocols, and promoting the coordination of stakeholders within the regional stranding network in the middle Magdalena Basin. This approach, in addition to supporting the capacity building of communities, institutions, and organizations for improving response knowledge, conservation, and manatee recovery, is of paramount importance for the long-term sustainability of manatee populations in the region.
48
Niemuth, Jennifer N., Casey C. Ransom, Sarah A. Finn, Matthew H. Godfrey, Stacy A. C. Nelson, and Michael K. Stoskopf. "Using Random Forest Algorithm to Model Cold Stunning Events in Sea Turtles in North Carolina." Journal of Fish and Wildlife Management, May 14, 2020, 0000. http://dx.doi.org/10.3996/052019-jfwm-043.
Full textAbstract:
Sea turtle strandings due to cold stunning are seen when turtles are exposed to ocean temperatures that acutely and persistently drop below approximately 12 °C. In North Carolina, this syndrome affects imperiled loggerhead Caretta caretta, green Chelonia mydas, and Kemp's ridley Lepidochelys kempii sea turtle species. Based on oceanic and meteorological patterns of cold stunning in sea turtles, we hypothesized that we could predict the daily size of cold stunning events in North Carolina using random forest models. We used cold stunning data from the North Carolina Sea Turtle Stranding and Salvage Network from 2010-2015 and oceanic and meteorological data from the National Data Buoy Center from 2009-2015 to create a random forest model that explained 99% of the variance. We explored additional models using the 10 and 20 most important variables or only oceanic and meteorological variables. These models explained similar percentages of variance. The variables most frequently found to be important were related to air temperature, atmospheric pressure, wind direction, and wind speed. Surprisingly, variables associated with water temperature, which is critical from a biological perspective, were not among the most important variables identified. We also included variables for the mean change in these metrics daily from 4 days prior to the day of stranding. These variables were among the most important in several of our models, especially the change in mean air temperature from 4 days prior to stranding to the day of stranding. The importance of specific variables from our RF models can be used to guide the selection of future model predictors to estimate daily size of cold stunning events. We plan to apply the results of this study to a predictive model that can serve as a warning system and to a downscaled climate projection to determine the potential impact of climate change on cold stunning event size in the future.
49
Wund, S., E. Méheust, C. Dars, et al. "Strengthening the health surveillance of marine mammals in the waters of metropolitan France by monitoring strandings." Frontiers in Marine Science 10 (May 1, 2023). http://dx.doi.org/10.3389/fmars.2023.1116819.
Full textAbstract:
Monitoring the health status of marine mammals is a priority theme that France aims to develop with the other European Union Member States in the next two years, in the context of the Marine Strategy Framework Directive. With approximately 5,000 km of coastline and for nearly ten years, France has been recording an average of 2,000 strandings per year, which are monitored by the National Stranding Network, managed by Pelagis, the observatory for the conservation of marine mammals from La Rochelle University and the French National Center for Scientific Research. Since 1972, this network has successively evolved from spatial and temporal faunistic description to, nowadays, the detection of major causes of mortality. It now aims to carry out epidemiological studies on a population scale. Thus, a strategy to strengthen the monitoring of marine mammals’ health status based on stranding data has been developed. This strategy will allow for a more accurate detection of anthropogenic cause of death as well as those of natural origin. It will allow the monitoring of time trends and geographical differences of diseases associated with conservation and public health issues while ensuring the early detection of emerging and/or zoonotic diseases of importance. It will also allow a better assessment of the consequences of human activities on these animal populations and on the environment. Thus, this strategy is fully in line with the “One Health” approach which implies an integrated vision of public, animal and environmental health. It is broken down into four surveillance modalities: (1) general event-based surveillance (GES); (2) programmed surveillance (PS); (3) specific event-based surveillance (SES); (4) and in the longer term, syndromic surveillance (SyS). This article describes the French strategy as well as these different surveillance modalities, the levels of examinations and the associated sampling protocols and finally, the method of standardisation of the data collected. The objective is to present the strategy developed at the French level in order to integrate it into a future strategy shared at the European level to standardise practices and especially complementary analysis, necessary for a better evaluation of the health status of these mobile marine species.
50
Smith, Jayme, Jacob A. Cram, Malena P. Berndt, Vanessa Hoard, Dana Shultz, and Alissa C. Deming. "Quantifying the linkages between California sea lion (Zalophus californianus) strandings and particulate domoic acid concentrations at piers across Southern California." Frontiers in Marine Science 10 (December 1, 2023). http://dx.doi.org/10.3389/fmars.2023.1278293.
Full textAbstract:
Domoic acid-producing blooms of the diatom genus Pseudo-nitzschia are pervasive in coastal environments globally. Domoic acid, a neurotoxin, accumulates via trophic transfer into marine food webs and is often associated with mass marine mammal mortality and stranding events. In Southern California, California sea lions (Zalophus californianus) are an indicator species for food web impacts of domoic acid because they are abundant secondary consumers, sensitive to domoic acid intoxication, and are actively monitored by stranding networks. However, domoic acid exposure may occur a distance from where a sea lion ultimately strands. This spatiotemporal variation complicates coupling domoic acid observations in water to strandings. Therefore, we sought to quantify whether monitoring data from four pier sites across the region, covering nearly 700 km of coastline from 2015-2019, could be used to predict adult and subadult sea lion strandings along the 68 km Orange County coastline surveyed by the Pacific Marine Mammal Center. We found that increased sea lion strandings were often observed just prior to an increase in particulate domoic acid at the piers, confirming that clusters of subadult and adult sea lion strandings with clinical signs of domoic acid intoxication serve as indicators of bloom events. In addition, domoic acid concentrations at Stearns Wharf, nearly 200 km from stranding locations, best predicted increased total sea lion strandings, and strandings of sea lions with domoic acid intoxication symptoms. Particulate domoic acid concentrations greater than 0.05 μg/L at Stearns Wharf were linked to stranding probabilities in Orange County ranging from 2.2% to 55% per week, and concentrations of 0.25 μg/L resulted in weekly stranding probabilities ranging from 16% to 81% depending on the stranding scenario modeled.