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Persistent organochlorine residues in harbour porpoise (Phocoena phocoena) from the Black Sea.
1997
Tanabe S. | Madhusree B. | Ozturk A.A. | Tatsukawa R. | Miyazaki N. | Ozdamar E. | Aral O. | Samsun O. | Ozturk B.
The impact of marine debris on cetaceans with consideration of plastics generated by the COVID-19 pandemic Texto completo
2022
Eisfeld-Pierantonio, Sonja Mareike | Pierantonio, Nino | Simmonds, Mark P.
The accumulation of human-derived debris in the oceans is a global concern and a serious threat to marine wildlife. There is a volume of evidence that points to deleterious effects of marine debris (MD) on cetaceans in terms of both entanglement and ingestion. This review suggests that about 68% of cetacean species are affected by interacting with MD with an increase in the number of species reported to have interacted with it over the past decades. Despite the growing body of evidence, there is an ongoing debate on the actual effects of plastics on cetaceans and, in particular, with reference to the ingestion of microplastics and their potential toxicological and pathogenic effects. Current knowledge suggests that the observed differences in the rate and nature of interactions with plastics are the result of substantial differences in species-specific diving and feeding strategies. Existing projections on the production, use and disposal of plastics suggest a further increase of marine plastic pollution. In this context, the contribution of the ongoing COVID-19 pandemic to marine plastic pollution appears to be substantial, with potentially serious consequences for marine life including cetaceans. Additionally, the COVID-19 pandemic offers an opportunity to investigate the direct links between industry, human behaviours and the effects of MD on cetaceans. This could help inform management, prevention efforts, describe knowledge gaps and guide advancements in research efforts. This review highlights the lack of assessments of population-level effects related to MD and suggests that these could be rather immediate for small populations already under pressure from other anthropogenic activities. Finally, we suggest that MD is not only a pollution, economic and social issue, but also a welfare concern for the species and populations involved.
Mostrar más [+] Menos [-]Marine mammals and microplastics: A systematic review and call for standardisation Texto completo
2021
Zantis, Laura J. | Carroll, Emma L. | Nelms, Sarah E. | Bosker, Thijs
Microplastics receive significant societal and scientific attention due to increasing concerns about their impact on the environment and human health. Marine mammals are considered indicators for marine ecosystem health and many species are of conservation concern due to a multitude of anthropogenic stressors. Marine mammals may be vulnerable to microplastic exposure from the environment, via direct ingestion from sea water, and indirect uptake from their prey. Here we present the first systematic review of literature on microplastics and marine mammals, composing of 30 studies in total. The majority of studies examined the gastrointestinal tracts of beached, bycaught or hunted cetaceans and pinnipeds, and found that microplastics were present in all but one study, and the abundance varied between 0 and 88 particles per animal. Additionally, microplastics in pinniped scats (faeces) were detected in eight out of ten studies, with incidences ranging from 0% of animals to 100%. Our review highlights considerable methodological and reporting deficiencies and differences among papers, making comparisons and extrapolation across studies difficult. We suggest best practices to avoid these issues in future studies. In addition to empirical studies that quantified microplastics in animals and scat, ten studies out of 30 (all focussing on cetaceans) tried to estimate the risk of exposure using two main approaches; i) overlaying microplastic in the environment (water or prey) with cetacean habitat or ii) proposing biological or chemical biomarkers of exposure. We discuss advice and best practices on research into the exposure and impact of microplastics in marine mammals. This work on marine ecosystem health indicator species will provide valuable and comparable information in the future.
Mostrar más [+] Menos [-]Polychlorinated naphthalenes (PCNs) in sub-Arctic and Arctic marine mammals, 1986–2009 Texto completo
2012
Rotander, Anna | van Bavel, Bert | Riget, Frank | Auðunsson, Guðjón Atli | Polder, Anuschka | Gabrielsen, Geir Wing | Víkingsson, Gísli | Mikkelsen, Bjarni | Dam, Maria
Polychlorinated naphthalenes (PCNs) in sub-Arctic and Arctic marine mammals, 1986–2009 Texto completo
2012
Rotander, Anna | van Bavel, Bert | Riget, Frank | Auðunsson, Guðjón Atli | Polder, Anuschka | Gabrielsen, Geir Wing | Víkingsson, Gísli | Mikkelsen, Bjarni | Dam, Maria
A selection of PCN congeners was analyzed in pooled blubber samples of pilot whale (Globicephala melas), ringed seal (Phoca hispida), minke whale (Balaenoptera acutorostrata), fin whale (Balaenoptera physalus), harbour porpoise (Phocoena phocoena), hooded seal (Cystophora cristata) and Atlantic white-sided dolphin (Lagenorhynchus acutus), covering a time period of more than 20 years (1986–2009). A large geographical area of the North Atlantic and Arctic areas was covered. PCN congeners 48, 52, 53, 66 and 69 were found in the blubber samples between 0.03 and 5.9 ng/g lw. Also PCBs were analyzed in minke whales and fin whales from Iceland and the total PCN content accounted for 0.2% or less of the total non-planar PCB content. No statistically significant trend in contaminant levels could be established for the studied areas. However, in all species except minke whales caught off Norway the lowest ∑PCN concentrations were found in samples from the latest sampling period.
Mostrar más [+] Menos [-](Table 2) Concentrations of polychlorinated naphthalene congeners in blubber samples from whales, seals and porpoises between 1986-2009 Texto completo
2012
Rotander, Anna | van Bavel, Bert | Rigét, Frank F | Auðunsson, Guðjón Atli | Polder, Anuschka | Gabrielsen, Geir W | Víkingsson, Gísli | Mikkelsen, Bjarni | Dam, Maria
A selection of PCN congeners was analyzed in pooled blubber samples of pilot whale (Globicephala melas), ringed seal (Phoca hispida), minke whale (Balaenoptera acutorostrata), fin whale (Balaenoptera physalus), harbour porpoise (Phocoena phocoena), hooded seal (Cystophora cristata) and Atlantic whitesided dolphin (Lagenorhynchus acutus), covering a time period of more than 20 years (1986-2009). A large geographical area of the North Atlantic and Arctic areas was covered. PCN congeners 48, 52, 53, 66 and 69 were found in the blubber samples between 0.03 and 5.9 ng/g lw. Also PCBs were analyzed in minke whales and fin whales from Iceland and the total PCN content accounted for 0.2% or less of the total non-planar PCB content. No statistically significant trend in contaminant levels could be established for the studied areas. However, in all species except minke whales caught off Norway the lowest Sum PCN concentrations were found in samples from the latest sampling period.
Mostrar más [+] Menos [-]Who’s better at spotting? A comparison between aerial photography and observer-based methods to monitor floating marine litter and marine mega-fauna Texto completo
2020
Garcia-Garin, Odei | Aguilar, Alex | Borrell, Asunción | Gozalbes, Patricia | Lobo, Agustín | Penadés-Suay, Jaime | Raga, Juan A. | Revuelta, Ohiana | Serrano, María | Vighi, Morgana
Who’s better at spotting? A comparison between aerial photography and observer-based methods to monitor floating marine litter and marine mega-fauna Texto completo
2020
Garcia-Garin, Odei | Aguilar, Alex | Borrell, Asunción | Gozalbes, Patricia | Lobo, Agustín | Penadés-Suay, Jaime | Raga, Juan A. | Revuelta, Ohiana | Serrano, María | Vighi, Morgana
Pollution by marine litter is raising major concerns due to its potential impact on marine biodiversity and, above all, on endangered mega-fauna species, such as cetaceans and sea turtles. The density and distribution of marine litter and mega-fauna have been traditionally monitored through observer-based methods, yet the advent of new technologies has introduced aerial photography as an alternative monitoring method. However, to integrate results produced by different monitoring techniques and consider the photographic method a viable alternative, this ‘new’ methodology must be validated. This study aims to compare observations obtained from the concurrent application of observer-based and photographic methods during aerial surveys. To do so, a Partenavia P-68 aircraft equipped with an RGB sensor was used to monitor the waters off the Spanish Mediterranean coast along 12 transects (941 km). Over 10000 images were collected and checked manually by a photo-interpreter to detect potential targets, which were classified as floating marine macro-litter, mega-fauna and seabirds. The two methods allowed the detection of items from the three categories and proved equally effective for the detection of cetaceans, sea turtles and large fish on the sea surface. However, the photographic method was more effective for floating litter detection and the observer-based method was more effective for seabird detection. These results provide the first validation of the use of aerial photography to monitor floating litter and mega-fauna over the marine surface.
Mostrar más [+] Menos [-]Who's better at spotting? Comparison between aerial photography and visual methods to monitor floating marine litter and marine mega-fauna Texto completo
2020
Garcia-Garin, Odei | Aguilar, Àlex | Borrell Thió, Assumpció | Gozalbes, Patricia | Lobo, Agustín | Raga, Juan A. | Revuelta, Ohiana | Serrano, Maria | Vighi, Morgana
Pollution by marine litter is raising major concerns due to its potential impact on marine biodiversity and, above all, on endangered mega-fauna species, such as cetaceans and sea turtles. The density and distribution of marine litter and mega-fauna have been traditionally monitored through observer-based methods, yet the advent of new technologies has introduced aerial photography as an alternative monitoring method. However, to integrate results produced by different monitoring techniques and consider the photographic method a viable alternative, this 'new' methodology must be validated. This study aims to compare observations obtained from the concurrent application of observer-based and photographic methods during aerial surveys. To do so, a Partenavia P-68 aircraft equipped with an RGB sensor was used to monitor the waters off the Spanish Mediterranean coast along 12 transects (941 km). Over 10000 images were collected and checked manually by a photo-interpreter to detect potential targets, which were classified as floating marine macro-litter, mega-fauna and seabirds. The two methods allowed the detection of items from the three categories and proved equally effective for the detection of cetaceans, sea turtles and large fish on the sea surface. However, the photographic method was more effective for floating litter detection and the observer-based method was more effective for seabird detection. These results provide the first validation of the use of aerial photography to monitor floating litter and mega-fauna over the marine surface.
Mostrar más [+] Menos [-]Investigation of silver (Ag) deposition in tissues from stranded cetaceans by autometallography (AMG) Texto completo
2018
Li, Wenda | Zhang, Huiwen | Chen, Meng-Hsien | Chiou, Hue-Ying | Liou, Bang-Yeh | Pang, Victor Fei | Yang, Wei-Cheng | Jeng, Chian-Ren
Silver, such as silver nanoparticles (AgNPs), has been widely used in commercial products and may be released into the environment. The interaction between Ag deposition and biological systems is raising serious concerns because of one health consideration. Cetaceans, as the top predators of the oceans, may be exposed to Ag/Ag compounds and suffer negative health impacts from the deposition of these compounds in their bodies. In the present study, we utilized autometallography (AMG) to localize the Ag in the liver and kidney tissues of cetaceans and developed a model called the cetacean histological Ag assay (CHAA) to estimate the Ag concentrations in the liver and kidney tissues of cetaceans. Our results revealed that Ag was mainly located in hepatocytes, Kupffer cells and the epithelial cells of some proximal renal tubules. The tissue pattern of Ag/Ag compounds deposition in cetaceans was different from those in previous studies conducted on laboratory rats. This difference may suggest that cetaceans have a different metabolic profile of Ag, so a presumptive metabolic pathway of Ag in cetaceans is advanced. Furthermore, our results suggest that the Ag contamination in cetaceans living in the North-western Pacific Ocean is more severe than that in cetaceans living in other marine regions of the world. The level of Ag deposition in cetaceans living in the former area may have caused negative impacts on their health condition. Further investigations are warranted to study the systemic Ag distribution, the cause of death/stranding, and the infectious diseases in stranded cetaceans with different Ag concentrations for comprehensively evaluating the negative health effects caused by Ag in cetaceans.
Mostrar más [+] Menos [-]Natural and anthropogenically-produced brominated compounds in endemic dolphins from Western South Atlantic: Another risk to a vulnerable species Texto completo
2012
Alonso, Mariana B. | Eljarrat, Ethel | Gorga, Marina | Secchi, Eduardo R. | Bassoi, Manuela | Barbosa, Lupércio | Bertozzi, Carolina P. | Marigo, Juliana | Cremer, Marta | Domit, Camila | Azevedo, Alexandre F. | Dorneles, Paulo R. | Torres, João Paulo M. | Lailson-Brito, José | Malm, Olaf | Barceló, Damià
Liver samples from 53 Franciscana dolphins along the Brazilian coast were analyzed for organobrominated compounds. Target substances included the following anthropogenic pollutants: polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs), pentabromoethylbenzene (PBEB), hexabromobenzene (HBB), decabromodiphenylethane (DBDPE), as well as the naturally-generated methoxylated-PBDEs (MeO-PBDEs). PBDE concentrations ranged from 6 to 1797 ng/g lw (mean 166 ± 298 ng/g lw) and were similar to those observed in cetaceans from Northern Hemisphere. PBBs were found in all sampling locations (<LOQ to 57 ng/g lw). DBDPE was detected in 42% of the dolphins from the most industrialized Brazilian state and the concentrations ranging from <LOQ to 352 ng/g lw. Franciscana dolphins from the tropical Brazilian shore presented the highest MeO-PBDE concentrations ever reported for coastal cetaceans (up to 14 μg/g lw). Eight MeO-PBDE congeners were detected and the present investigation constituted the first record of occurrence of six of them in marine mammal livers.
Mostrar más [+] Menos [-]Seasonal and diel patterns in cetacean use and foraging at a potential marine renewable energy site Texto completo
2018
Nuuttila, Hanna K. | Bertelli, Chiara M. | Mendzil, Anouska | Dearle, Nessa
Marine renewable energy (MRE) developments often coincide with sites frequented by small cetaceans. To understand habitat use and assess potential impact from development, echolocation clicks were recorded with acoustic click loggers (C-PODs) in Swansea Bay, Wales (UK). General Additive Models (GAMs) were applied to assess the effects of covariates including month, hour, tidal range and temperature. Analysis of inter-click intervals allowed the identification of potential foraging events as well as patterns of presence and absence. Data revealed year-round presence of porpoise, with distinct seasonal and diel patterns. Occasional acoustic encounters of dolphins were also recorded. This study provides further evidence of the need for assessing temporal trends in cetacean presence and habitat use in areas considered for development. These findings could assist MRE companies to monitor and mitigate against disturbance from construction, operation and decommissioning activities by avoiding times when porpoise presence and foraging activity is highest in the area.
Mostrar más [+] Menos [-]Tissue concentrations of four Taiwanese toothed cetaceans indicating the silver and cadmium pollution in the western Pacific Ocean Texto completo
2017
Chen, Meng-Hsien | Zhuang, Ming-Feng | Zhou, Lianxiang | Liu, Jean-Yi | Shih, Chieh-Chih | Chen, Chiee-Young
Muscle, lung, kidney and liver tissues of 45 bycatch and stranded cetaceans, including 14 Grampus griseus (Gg), 7 Kogia simus (Ks), 10 Lagenodelphis hosei (Lh), and 14 Stenella attenuata (Sa), were collected in the waters off Taiwan from 1994 to 1995, and from 2001 to 2012. Baseline concentrations (in μgg−1 dry weight) of the cetaceans were lung (<0.05)=muscle (<0.05)<kidney (0.08±0.04)<liver (0.43±0.28) for Ag, and muscle (0.03±0.03)=lung (0.22±0.19)<liver (3.82±3.50)<kidney (16.22±18.81) for Cd. Unhealthy and critically dangerous Ag and Cd tissue concentrations in the toothed cetaceans are suggested. Marked high concentrations of Ag and Cd found in Gg and Lh are highly related to their squid-eating and deep diving habits. The highest ever recorded concentrations of liver-Ag and kidney-Cd were found in two Lh. These Taiwanese cetaceans indicate marked Ag and Cd pollution in the recent two decades in the western Pacific Ocean.
Mostrar más [+] Menos [-]Bayesian spatial modeling of cetacean sightings during a seismic acquisition survey Texto completo
2016
Vilela, Raul | Pena, Ursula | Esteban, Ruth | Koemans, Robin
A visual monitoring of marine mammals was carried out during a seismic acquisition survey performed in waters south of Portugal with the aim of assessing the likelihood of encountering Mysticeti species in this region as well as to determine the impact of the seismic activity upon encounter.Sightings and effort data were assembled with a range of environmental variables at different lags, and a Bayesian site-occupancy modeling approach was used to develop prediction maps and evaluate how species-specific habitat conditions evolved throughout the presence or not of seismic activity.No statistical evidence of a decrease in the sighting rates of Mysticeti by comparison to source activity was found. Indeed, it was found how Mysticeti distribution during the survey period was driven solely by environmental variables.Although further research is needed, possible explanations may include anthropogenic noise habituation and zone of seismic activity coincident with a naturally low density area.
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