1,721,045 research outputs found
Cetaceans as Ocean Health Indicators of Marine Litter Impact at Global Scale
Full text linkMarine litter is a growing concern for marine animals, including cetaceans for which there is a developing body of evidence showing impacts of both entanglement and ingestion. Better understanding is needed of the current and predicted scales of impacts on cetacean species of both macro- and micro-litter. Some emerging methodological approaches, such as the "threefold approach," will help address data gaps. The relationship between this form of pollution and some cetaceans is strong and the particular feeding habits, and widespread distribution of two whale species means that they can be proposed as ocean health indicators for macro- and micro-litter impacts at global scales, helping steer research. The species concerned are sperm whales (Physeter macrocephalus), for macro-litter at depth, and fin whales (Balaenoptera physalus), for micro-debris. Once appropriate techniques have been fully developed for non-lethal assessment, other whale species might also be used as indicators of litter pollution in their specific feeding zones
Cetaceans as a potential indicators of microand macroplastic impact in the marine environment: Trend topic and emerging gaps
No full textHow can 5 mm plastic debris (microplastics) affect filter feeder baleen whales? How can kilograms of plastic debris affect sperm whales? Here, we report the scientific evidence and the emerging gaps of the interaction between the charismatic megafauna
(filter feeder baleen whales and deep divers) and micro- and macroplastics studying their impact and their related toxicological effects. We also propose these species as candidate indicators for micro- and macro-plastic pollution, respectively, at global scale. Regarding the interaction between whales and microplastics the first warning was reported for Mediterranean fin whales (Balaenoptera physalus) since 2012, and confirmed later (high concentrations of PBTs, plastic additives and specific biomarker responses, detected in skin biopsies) in the same species and for other filter feeders (basking and whale sharks). Filter-feeding
megafauna are susceptible to high levels of microplastics ingestion and exposure to associated toxic compounds due to their feeding strategies and for habitat overlap with microplastic hot spots. For these reasons, this whale species has been proposed
as a candidate indicator of microplastics pollution in semi-enclosed basins. On the other hand, deep divers such as the sperm whale and the Cuvier's beaked whale, are exposed to the ingestion of marine litter (ML), including large plastic fragments, due to their feeding in marine canyons. High occurrence of ML (75%) has been reported in Mediterranean sperm whales. This species was recently proposed as a candidate indicator the presence of ML in the Mediterranean (IMAP indicator 24). As these megafauna species are charismatic and iconic indicators that serve as flagship species for marine conservation, this research field became recently a “trend topic”. However, several gaps must be resolved, such as the investigations of new plastic tracers in the tissues and the identification (through omics techniques) of the toxicological effects caused to plastic debris ingestion in these species
How to detect the impact of marine litter on Mediterranean biodiversity?
No full textThe Mediterranean Sea has been recently described as one of the most affected
areas by marine litter, including microplastics, in the world. Recent studies
in the different regions of the basin suggested that some areas are affected by
important concentration of microplastics and plastic additives, representing a
potential risk for endangered species (baleen whales, filter feeders’ sharks and
sea turtles) and for the all Mediterranean biodiversity. To cover the current
knowledge gaps on this issue a harmonised methodological approach for the
assessment of the marine debris impact on Mediterranean biodiversity is needed.
The quantification of marine litter, and particularly microplastics, in the marine
environment can depend on several environmental factors and change according
to multiple oceanographic features, and therefore, cannot reflect the potential
impact on organisms and ecosystems. The information obtained by biondicator
species could better integrate the spatial and temporal presence of marine litter/
microplastics in the marine environment. In addition, the use of biondicators
can allow to measure not only the occurrence of marine litter in the species
and its environment but also the threat posed to organisms by the evaluation
of contaminants accumulation and any related biological effect. To assess the
harm by marine litter ingestion a threefold approach, simultaneously measuring
the presence and effects (accumulation of plastic associated contaminants
and biomarker responses), can provide the harm and the sub-lethal effects to
organisms related marine litter impact. The gaps pointed out by this research
and the bioindicators species selected could represent a step forward for the
risk assessment and the implementation of future mitigation measure for the
Mediterranean area, habitat and species affected by marine litter ingestion. The
identification of the most representative bioindicator species for marine litter/
microplastics in the Mediterranean environment is one of the main goals of
the multidisciplinary strategy developed in the Plastic Busters SDSN-MED, the
Union for the Mediterranean project (UfM) (http://plasticbusters.unisi.it/)
A Review of Plastic-Associated Pressures: Cetaceans of the Mediterranean Sea and Eastern Australian Shearwaters as Case Studies
Full text linkImpacts of debris on marine fauna occur throughout the marine ecosystems, with adverse impacts documented on over 1,400 species; impacts can be divided into those arising from entanglement, and those from ingestion. Ingestion of, and entanglement in, debris has been documented in over 60% of all cetacean species. Seabirds are also impacted by debris predominately through entanglement and ingestion, with the number of species negatively impacted increasing from 138 to 174 over the past two decades. In the marine environment, cetaceans and seabirds are widely regarded as reliable sentinels due to their position near the top of the marine food web, conspicuous nature, and reliance on marine resources; for this reason, this paper is focused on seabirds and cetaceans as sentinels of ocean change. In particular, two case studies are considered in relation to different levels of environmental anthropogenic impact: the cetaceans of the Mediterranean Sea and seabirds of eastern Australia. Here we describe two recent studies used to diagnose the toxicological stress related to debris-associated pressures in cetaceans and seabirds. These studies highlight the diversity and scale of impacts being felt by marine species and the role these organisms can play in our society as charismatic sentinels of ocean health. Seabirds and marine mammals are exposed, in these key areas, to a variety of adversities that potentially decrease their survival or reproductive success. These include weather, food shortages, predators, competitors, parasites, disease, and human-induced effects and plastic pollution. Each factor affects seabirds and marine mammals in a different way, but more importantly, factors can also interact and create impacts far greater than any one factor alone. The Australian and Mediterranean case studies presented here emphasize the need to consider multiple sources of mortality when developing management plans for the conservation of vulnerable species
First data on plastic ingestion by blue sharks (Prionace glauca) from the Ligurian Sea (North-Western Mediterranean Sea)
Full text linkFew studies have focused so far on plastic ingestion by sharks in the Mediterranean Sea. The aim of this paper was to determine, for the first time, the plastic litter ingested by blue sharks (Prionace glauca), categorized as “Critically Endangered” in the Mediterranean Sea by IUCN, caught in the Pelagos Sanctuary SPAMI (North-Western Mediterranean Sea). The analysis of the stomach contents was performed following the MSFD Descriptor 10 standard protocol implemented with FT-IR spectroscopy technique. The results showed that 25.26% of sharks ingested plastic debris of wide scale of sizes from microplastics (<5 mm) to macroplastics (>25 mm). The polyethylene sheetlike user plastics, widely used as packaging material, are the most ingested debris. This research raises a warning alarm on the impact of plastic debris on a threatened species, with a key role in the food web, and adds important information for futures mitigation actions
First ecotoxicological investigation in Whale shark of the Gulf of California (Mexico) using skin biopsy
No full textExposure to virgin and marine incubated microparticles of biodegradable and conventional polymers modulates the hepatopancreas transcriptome of Mytilus galloprovincialis
Full text linkBiodegradable polymers have been proposed as an alternative to conventional plastics to mitigate the impact of marine litter, but the research investigating their toxicity is still in its infancy. This study evaluates the potential ecotoxicological effects of both virgin and marine-incubated microparticles (MPs), at environmentally relevant concentration (0.1 mg/l), made of different biodegradable polymers (Polycaprolactone, Mater-Bi, cellulose) and conventional polymers (Polyethylene) on Mytilus galloprovincialis by using transcriptomics. This approach is increasingly being used to assess the effects of pollutants on organisms, obtaining data on numerous biological pathways simultaneously. Whole hepatopancreas de novo transcriptome sequencing was performed, individuating 972 genes differentially expressed across experimental groups compared to the control. Through the comparative transcriptomic profiling emerges that the preponderant effect is attributable to the marine incubation of MPs, especially for incubated polycaprolactone (731 DEGs). Mater-Bi and cellulose alter the smallest number of genes and biological processes in the mussel hepatopancreas. All microparticles, regardless of their polymeric composition, dysregulated innate immunity, and fatty acid metabolism biological processes. These findings highlight the necessity of considering the interactions of MPs with the environmental factors in the marine ecosystem when performing ecotoxicological evaluations. The results obtained contribute to fill current knowledge gaps regarding the potential environmental impacts of biodegradable polymers
Abundance and characterization of microplastics in the coastal waters of Tuscany (Italy): The application of the MSFD monitoring protocol in the Mediterranean Sea
No full textMonitoring efforts are required to understand the sources, distribution and abundance of microplastic pollution. To verify the abundance of microplastics along the Tuscan coastal waters (Italy), water-column and surface samples were collected in two seasons across four transects at different distances to the coast (0.5, 5, 10 and 20 km), within the implementation of the European Marine Strategy Framework Directive. The results show an average concentration of 0.26 items/m3 in the water-column samples and 41.1 g/km2 and 69,161.3 items/km2 of floating microplastics, with an increase with the distance to the coast The seasonality and the sampling area do not affect the abundance of microplastics. The most abundant size class is 1-2.5 mm as fragments and sheets suggesting that fragmentation of larger polyethylene and polypropylene items could be the main source of microplastics. These data represent the application of a harmonized protocol to make the data on microplastics comparable and reliable
Anthropogenic fibers in the Mediterranean sea: Methods and monitoring of an overlooked category of microparticles in the water column
Full text linkAnthropogenic particles (APs) are widespread in the marine environment, but knowledge gaps remain regarding anthropogenic fibers. This study aimed to evaluate the presence of APs, including natural and synthetic fibers, in the water column. A literature review on fibers in Mediterranean seawater revealed that current sampling methods are underdeveloped. Two sampling methods were compared to determine the best approach for collecting fibers: a new in-situ pump (20 μm mesh filter) and a WP2 plankton net (200 μm). The in-situ pump was the most effective method and was applied in three areas of the Western Mediterranean Sea (Gulf of Asinara, Capraia Island, Capo Carbonara). The predominant APs, characterized by μFTIR, were cellulose and polyester fibers, reflecting the global textile fiber production. The Asinara area was the most impacted area (average of 393.7 items/m3). This study highlights the ubiquitous presence of fibers in the water column and underscores the need for further investigation of potential impacts on marine biota
Abundance and characterization of floating microplastics along the Tuscany coast (Italy): the first aplication of the MSFD monitoring proticol
No full textDue to the increasing use of plastic and its dispersion in the marine environment andaccumulation in all habitats, the issue of plastic debris needs to be deeply investigated [1]. In particular, despite the Mediterranean sea is one of the hot spot area in the world for plastic debris accumulation [2], the knowledge on distribution and occurrence of floating microplastics is still lacking. Microplastics can affect marine biota increasing the likelihoodof ingestion of plastics by marine organisms entering the food web. For this reason the European Union has promoted the Marine Strategy Framework Directive (MSFD) with the aim of reaching the "Good Environmental Status" by 2020. This work has been carried out as part of implementation of the Descriptor 10.1.3 [3] of the MSFD in Tuscany (Italy), with the aim to gain information on abundance and distribution of microplastics. Sampling has been realized in two seasons (winter and spring) using a manta trawl (330 μm mesh size). Samples were collected along 4 transects 100 km far from each other, located from the estuary of Arno river to the promontory of Argentario. Each transect was divided into 4 stations located at increasing distance from the coast (20 km, 10 km, 5 km, 0.5 km). The analysis were performed according to the MSFD protocol. All data was normalized to the total volume of water filtered and expressed as items/m3 and microplastics were characterized by colour, shape and size. A total of 2670 microplastics were isolated in the 72 samples, white was the predominant color; the majority of items are fragments and the most of microplastics fall in the measured from 1 to 2.5mm size class. In the winter, the highest values of microplastics have been found in the station at 20 km from the coast with a gradient decreasing in the stations closer to coast; whereas in spring, the highest was found in the station at 10 km. This work represents the first application of the MSFD protocol in the monitoring of microplastics in Tuscany and will allow to understand the distribution and abundance of microplastics in the Tuscany coastal waters
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