Marine Monitoring Programs Research Articles

Exposure of Mytilus galloprovincialis to Microplastics: Accumulation, Depuration and Evaluation of the Expression Levels of a Selection of Molecular Biomarkers.

Microplastic contamination is a growing marine environmental issue with possible consequences for seafood safety. Filter feeders are the target species for microplastic (MPs) pollution because they filter large quantities of seawater to feed. In the present study, an experimental contamination of Mytilus galloprovincialis was conducted using a mixture of the main types of MPs usually present in the seawater column (53% filaments, 30% fragments, 3% granules) in order to test the purification process as a potential method for removing these contaminants from bivalves intended for human consumption. A set of molecular biomarkers was also evaluated in order to detect any variations in the expression levels of some genes associated with biotransformation and detoxification, DNA repair, cellular response, and the immune system. Our results demonstrate that: (a) the purification process can significantly reduce MP contamination in M. galloprovincialis; (b) a differential expression level has been observed between mussels tested and in particular most of the differences were found in the gills, thus defining it as the target organ for the use of these biomarkers. Therefore, this study further suggests the potential use of molecular biomarkers as an innovative method, encouraging their use in next-generation marine monitoring programs.

Modelling buoyancy-driven vertical movement of Trichodesmium application in the Great Barrier Reef

Trichodesmium cells aggregate and form single trichomes or larger colonies and possess strong intracellular gas vesicles that generate strong positive buoyancy and facilitate the vertical migration of colonies. Trichodesmium is proposed to be an important source of nitrogen in the Great Barrier Reef (GBR) with implications for nutrient cycling and eutrophication. To understand the dynamics of Trichodesmium in the GBR ecosystem, reliable model predictions of Trichodesmium growth, nitrogen fixation and distribution are required. The sinking rates of Trichodesmium colonies have been reported to be dependent on the shape and size of colonies, and the orientation of colonies in seawater. Therefore, to better simulate the vertical movement of Trichodesmium in the GBR, and subsequent biogeochemical dynamics, the Trichodesmium processes in the eReefs biogeochemical model was modified by applying the form resistance factor to the sinking velocities of tuft-shaped Trichodesmium colonies. Our model results compare well with observations from the Australian Institute of Marine Science Marine Monitoring Program sensor network sites and capture the emergent patterns of phytoplankton size spectrum observed in nature. The modified model formulations improve the physiological realism of the Trichodesmium growth submodel of the eReefs marine biogeochemical models, and can help to improve the understanding of Trichodesmium dynamics for effective GBR water quality management.

Posidonia Spheroids Intercepting Plastic Litter: Implications for Beach Clean-Ups

This study represents the first assessment of plastic waste within Posidonia spheroids on four sandy, Mediterranean beaches, each characterized by varying levels of anthropogenic influence. Fifty-five (68.7%) spheroids, out of eighty examined, included plastic litter. A total of 202 plastic items were isolated. Plastic abundance was 2.5 items/spheroid corresponding to 132 items per kilogram. The length of plastic items ranged from 0.1 to 50 mm. Fibers, tangled fibers and fragments were the most common shapes. The spheroids exhibited a substantial capacity for trapping plastic waste, with notable differences among the beaches. Our results underscore the significance of implementing a beach clean-up plan aimed at removing all spheroids to prevent them from disintegrating and releasing trapped plastic waste into the environment. Manual removal is recommended to safeguard the beaches, and this process should target all spheroids, regardless of their size. This study provides valuable insights that can inform marine litter monitoring programs, contribute to the development of tailored management measures, and support the implementation of specific action plans to mitigate Mediterranean microplastic pollution.

Top 10 marine litter items on the seafloor in European seas from 2012 to 2020

We studied the ten most frequently encountered litter items from the seafloor in European seas to advance actions and inform future mitigation measures to reduce marine litter and the associated social, economic and environmental impacts it has on European seas and beyond. Data were collected during trawl surveys from 2012 to 2020 as part of national and regional marine litter monitoring programmes in the Greater North Sea (5652 trawls), Celtic Seas (3505), Bay of Biscay (651), and Baltic Sea (3688). A Bayesian approach is used to quantify the variation in the item rankings. Overall, plastic items predominate in the top positions in each area. Synthetic rope, plastic sheets, monofilament fishing line and plastic bags occupy four of the top five positions for each of the Greater North Sea, Celtic Seas and the Bay of Biscay. Items from fishing and rope (representing mainly other maritime activities) are strongly represented in the top ten lists from three of our four areas, with synthetic rope, fishing nets, and tangled and untangled monofilament fishing line listed in the top seven positions for the Greater North Sea, Celtic Seas and the Bay of Biscay. The top ten items in the Baltic Sea are of a different profile to the other regions, but the most commonly caught items are still predominantly plastic, with plastic sheets, other plastic items and plastic bags occupying three of the top four positions.The findings in this study highlight the need to address sea-based sources to try and eliminate litter from fishing and maritime activities. Measures such as improved port reception facilities, marking of fishing gear, promoting reporting of the loss of fishing gear and increasing public awareness should be introduced.

Marine monitoring in transition: On the verge of technological revolution?

Efforts to renew marine ecosystem monitoring to include advanced technology and cost-effective methods have been repeatedly called for. The current environmental legislation in European Union (EU) requires also ecosystem monitoring beyond the scope of conventional methods and sampling strategies. Despite several studies showing the benefits of new methods, the progress to adopt the methods in national monitoring programmes under legal requirements has been slow. In this study, we have reviewed the current use of a set of methods in marine monitoring programmes under the EU marine strategy framework directive (MSFD), which calls for a holistic view of the marine environment and thus requires tens of monitoring parameters by different methods. Here we assess how widely the new methods are being adopted in the EU member states implementing the MSFD. Our results show a relatively high adoption rate for certain methods, while others are widely ignored. We compare the results also with the monitoring strategies of the four regional sea conventions. We argue that the adoption of methods in European and regional programmes may positively influence the national use of new methods.

The role of benthic habitat mapping for science and managers: A multi-design approach in the Southeast Brazilian Shelf after a major man-induced disaster

Seabed mapping is currently the baseline information for ocean management and conservation, and is an indispensable item within research and Marine Spatial Planning. Here, we use a case study and published data along the southeast Brazilian continental shelf to illustrate the concepts and ideas of potential benthic habitat mapping and the importance of having maps on different scales and the potential for using a multi-design approach. The case analysis presented here uses a regional map and distinct criteria (seabed geodiversity and biodiversity, and potential influence of a tailings plume) to define three areas along the continental shelf to be mapped in a high-resolution, as part of a marine monitoring program. The background of the case study is a tailing dam failure disaster that led to the input of iron ore tailings in the ocean, leading to a major environmental disaster. Three areas were chosen, including: a Marine Protected Area (MPA Costa das Algas), a major fishing ground (the Doce River prodelta/depocenter), and an understudied reef area (Forgotten Reefs). Potential benthic habitat mapping was carried out using acoustic surveys (multibeam echosounder acquiring bathymetry and backscatter) and ground-truthing (sediment samples and seafloor image). Results detailed the potential habitats throughout the three areas, providing primary information for the study of benthic habitats and their distribution. The multi-design approach indicated that although a regional analysis can indicate potential vulnerability as a first assessment approach, high-resolution potential habitat mapping (herein, 20 m or finer) is beneficial to evaluate and produce a higher-confidence level for decision-makers. Having an overall view of what and where to collect new and finer data would be best to identify vulnerable areas that, in this case study, could be threatened by plume dispersion and tailings accumulation. Our results support the delineation of priority areas aiming for monitoring, protection and guiding for other studies, besides the consolidation of habitat importance and the integration of various datasets through a hierarchical classification scheme. Although Brazil has never produced a regional or national habitat map for the entire continental margin, there are already conditions to plan, execute and maintain a habitat mapping program, partnering with Universities, Government Institutions (e.g., the Brazilian Navy), and the private sector. In the context of the UN Decade of Ocean Science targets, it is urgent to plan and implement a national database capable of supporting a habitat classification effort on a broader national scale, with the flexibility to support a multi-design or a multi-scale approach.

Establishing a marine monitoring programme to assess antibiotic resistance: A case study from the Gulf Cooperation Council (GCC) region.

The World Health Organization considers antimicrobial resistance as one of the most pressing global issues which poses a fundamental threat to human health, development, and security. Due to demographic and environmental factors, the marine environment of the Gulf Cooperation Council (GCC) region may be particularly susceptible to the threat of antimicrobial resistance. However, there is currently little information on the presence of AMR in the GCC marine environment to inform the design of appropriate targeted surveillance activities. The objective of this study was to develop, implement and conduct a rapid regional baseline monitoring survey of the presence of AMR in the GCC marine environment, through the analysis of seawater collected from high-risk areas across four GCC states: (Bahrain, Oman, Kuwait, and the United Arab Emirates). 560 Escherichia coli strains were analysed as part of this monitoring programme between December 2018 and May 2019. Multi-drug resistance (resistance to three or more structural classes of antimicrobials) was observed in 32.5% of tested isolates. High levels of reduced susceptibility to ampicillin (29.6%), nalidixic acid (27.9%), tetracycline (27.5%), sulfamethoxazole (22.5%) and trimethoprim (22.5%) were observed. Reduced susceptibility to the high priority critically important antimicrobials: azithromycin (9.3%), ceftazidime (12.7%), cefotaxime (12.7%), ciprofloxacin (44.6%), gentamicin (2.7%) and tigecycline (0.5%), was also noted. A subset of 173 isolates was whole genome sequenced, and high carriage rates of qnrS1 (60/173) and bla CTX-M-15 (45/173) were observed, correlating with reduced susceptibility to the fluoroquinolones and third generation cephalosporins, respectively. This study is important because of the resistance patterns observed, the demonstrated utility in applying genomic-based approaches to routine microbiological monitoring, and the overall establishment of a transnational AMR surveillance framework focussed on coastal and marine environments.

Sampling re-design increases power to detect change in the Great Barrier Reef's inshore water quality.

Monitoring programs are fundamental to understanding the state and trend of aquatic ecosystems. Sampling designs are a crucial component of monitoring programs and ensure that measurements evaluate progress toward clearly stated management objectives, which provides a mechanism for adaptive management. Here, we use a well-established marine monitoring program for inshore water quality in the Great Barrier Reef (GBR), Australia to investigate whether a sampling re-design has increased the program’s capacity to meet its primary objectives. Specifically, we use bootstrap resampling to assess the change in statistical power to detect temporal water quality trends in a 15-year inshore marine water quality data set that includes data from both before and after the sampling re-design. We perform a comprehensive power analysis for six water quality analytes at four separate study areas in the GBR Marine Park and find that the sampling re-design (i) increased power to detect trends in 23 of the 24 analyte-study area combinations, and (ii) resulted in an average increase in power of 34% to detect increasing or decreasing trends in water quality analytes. This increase in power is attributed more to the addition of sampling locations than increasing the sampling rate. Therefore, the sampling re-design has substantially increased the capacity of the program to detect temporal trends in inshore marine water quality. Further improvements in sampling design need to focus on the program’s capability to reliably detect trends within realistic timeframes where inshore improvements to water quality can be expected to occur.

Detecting long temporal trends of photosystem II herbicides (PSII) in the Great Barrier Reef lagoon

The Marine Monitoring Program (MMP) was established in 2005 to monitor the inshore health of the Great Barrier Reef (GBR) and evaluate progress towards water quality objectives in Reef Water Quality Improvement Plans. The MMP provides information on the magnitude and spatial extent of pesticide contamination, reports on temporal variability, and provides a risk assessment for the biota in the GBR lagoon. However, long-term trends in pesticide contamination of inshore marine waters over the entire monitoring period (2005–2018) have not been assessed. We used up to 14 years of monitoring data for five PSII herbicides (ametryn, atrazine, diuron, tebuthiuron, and hexazinone) to conduct temporal trend analyses at 11 inshore monitoring sites. The trend analyses suggested increasing significant trends (p < 0.05) for the five PSII herbicides concentrations at several monitoring sites. Power analysis indicated that monitoring sites with over 10 years of monitoring data had convincing results with 80% power.

Microplastics in different tissues of caught fish in the artificial reef area and adjacent waters of Haizhou Bay

In recent years, the microplastics (MPs) pollution in the offshore of microplastics has gradually become a concerning topic, and the understanding the accumulation of MPs in different tissues of organisms is also an important aspect. MPs can easily affect target tissues and transport related chemicals to humans through the food chain. MPs in the gills and guts of fish in the artificial reef area of Haizhou Bay and adjacent waters were detected in this study. The results showed that MPs were ubiquitous in the gills and guts of 26 species, with average quantities of 3.54 ± 2.14 pieces/fish and 3.00 ± 2.63 pieces/fish, respectively. More than 99% of the plastics were MPs that were less than 5 mm in diameter, with blue fiber being the most common. The number and quantity of MPs in gills were higher than those in guts in different habitat types, living water layers and feeding habits of fish. At the community level, as the body length and body weight increased, the quantity of MPs in the gills and guts showed a slight decreasing trend, and the correlation was not strong (P > 0.05). With increasing trophic levels (TLs), MPs were biomagnified in the guts (Trophic magnification factor, TMF = 1.37), but no change occurred in the gills (TMF = 1.00). We believe that biomagnification of MPs should be obtained by comparing the quantity of MPs in whole organisms rather than only in specific tissues before such conclusions can be defined. We recommend that periodic marine monitoring programs be implemented, as well as research into smaller MPs and even nanoplastics, to assess from the perspective of water, sediments, organisms and ecotoxicology, which will provide useful information for MPs pollution in artificial reefs and help to improve the MPs pollution database in China.

On Using Lagrangian Drift Simulations to Aid Interpretation of in situ Monitoring Data

One key challenge of marine monitoring programs is to reasonably combine information from different in situ observations spread in space and time. In that context, we suggest the use of Lagrangian transport simulations extending both forward and backward in time to identify the movements of water bodies from the time they were observed to the time of their synopsis. We present examples of how synoptic maps of salinity generated by this method support the identification and tracing of river plumes in coastal regions. We also demonstrate how we can use synoptic maps to delineate different water masses in coastal margins. These examples involve quasi-continuous observations of salinity taken along ferry routes. A third application is the synchronization of measurements between fixed stations and nearby moving platforms. Both observational platforms often see the same water body, but at different times. We demonstrate how the measurements from a fixed platform can be synchronized to measurements from a moving platform by taking into account simulation-based time shifts.

Spatial and size distribution of macro-litter on coastal dunes from drone images: A case study on the Atlantic coast

This work analyses the cross-shore (80 m) and long-shore (200 m) spatial and size distribution of macro-litter on coastal dunes, employing a mapping framework based on an Unmanned Aerial System (UAS, aka drone) and a GIS mobile application.Over the cross-shore, plastic percentage increased from 60% to 90% landwards. The largest items (processed wood) were found on the embryo dune. Plastic bottles and paper napkins were trapped by the foredune grass, while the largest fishing-related items were intercepted by the low scrub plant community on the backdune. Over the long-shore, plastic percentage and items size increased from the urbanized area towards the natural dunes.This work assessed the abundance of marine litter on coastal dune sectors, underlining the role of distinct vegetation types in trapping items of different size. The mapping framework can promote further marine litter monitoring programs and support specific strategies for protecting the dune ecosystems.

A Toolbox to Assist in Designing Marine Monitoring Programs for Offshore Storage Sites

Over the last few years a number of computational approaches have been developed that enable the optimisation of marine monitoring strategies for CCS. These include methods to: simulate and quantify hypothetical release events, identify highly sensitive criteria by which to distinguish anomalous biogeochemistry which may indicate a seep and define minimum deployments of monitoring platforms which guarantee an acceptable chance of detection. In order for these tools to be operationally useful it is necessary to place them in an accessible and integrated digital format that allows the methodologies to be applied coherently to multiple offshore storage sites and to answer specific stakeholder led questions around required sensitivity, cost and assurance levels. In this work we describe progress towards achieving this integration as well as the site specific data necessary to generate bespoke monitoring guidance.

NLossFinder-A Graphical User Interface Program for the Nontargeted Detection of DNA Adducts.

DNA adductomics is a relatively new omics approach aiming to measure known and unknown DNA modifications, called DNA adducts. Liquid chromatography–tandem mass spectrometry (LC-MS/MS) has become the most common method for analyzing DNA adducts. Recent advances in the field of mass spectrometry have allowed the possibility to perform a comprehensive analysis of adducts, for instance, by using a nontargeted data-independent acquisition method, with multiple precursor m/z windows as an inclusion list. However, the generated data are large and complex, and there is a need to develop algorithms to simplify and automate the time-consuming manual analysis that has hitherto been used. Here, a graphical user interface (GUI) program was developed, with the purpose of tracking a characteristic neutral loss reaction from tandem mass spectrometry of the nucleoside adducts. This program, called nLossFinder, was developed in the MATLAB platform, available as open-source code. Calf thymus DNA was used as a model for method optimization, and the overall adductomics approach was applied to DNA from amphipods (Monoporeia affinis) collected within the Swedish National Marine Monitoring Program. In the amphipod DNA, over 150 putative adducts were found in comparison to 18 using a manual approach in a previous study. The developed program can improve the processing time for large MS data, as it processes each sample in a few seconds, and hence can be applicable for high-throughput screening of adducts.

Unusual male size vs sperm count relationships in a coastal marine amphipod indicate reproductive impairment by unknown toxicants

Sperm quantity/quality are significant reproductive endpoints with clear links to population level dynamics. Amphipods are important model organisms in environmental toxicology. Despite this, field monitoring of male fertility in invertebrates has rarely been used in monitoring programs. The aim of this study was to compare sperm quality/quantity in an amphipod collected at six UK locations with differing water quality. Due to low sperm counts and an observed lack of relationship between sperm count and weight in amphipods collected from a nationally protected conservation area (Langstone Harbour, England), we also compared datasets from this site over a decade to determine the temporal significance of this finding. One collection to evaluate a female reproductive endpoint was also performed at this site. Interestingly, this harbour consistently presented some of the lowest sperm counts comparable to highly industrial sites and low eggs number from females. Amphipods collected from all the sites, except from Langstone Harbour, presented strong positive correlations between sperm count and weight. Given Langstone Harbour has several international and national protected statutes primarily for marine life and birds, our results indicate that E. marinus, one important food component for wading birds, might be impacted by unknown reproductive stressors. These unknown stressors maybe related to agricultural runoff, leachate from historical landfills and effluent from storm water overflows. This study highlights the importance of exploring new reproductive endpoints such as sperm quantity/quality in marine monitoring programs.

Methods for Monitoring for the Population Consequences of Disturbance in Marine Mammals: A Review

Assessing the nonlethal effects of disturbance and their population-level consequences is a significant ecological and conservation challenge, because it requires extensive baseline knowledge of behavioral patterns, life-history and demography. However, for many marine mammal populations, this knowledge is currently lacking and it may take decades to fill the gaps. During this time, undetected population declines may occur. In this study we identify methods that can be used to monitor populations subject to disturbance and provide insights into the processes through which disturbance may affect them. To identify and address the knowledge gaps highlighted above, we reviewed the literature to identify suitable response variables and methods for monitoring these variables. We also used existing models of the population consequences of disturbance (PCoD) to identify demographic characteristics (e.g. the proportion of immature animals in the population, or the ratio of calves/pups to mature females) that may be strongly correlated with population status and therefore provide early warnings of future changes in abundance. These demographic characteristics can be monitored using established methods such as visual surveys combined with photogrammetry, and capture-recapture analysis. Individual health and physiological variables can also inform PCoD assessment and can be monitored using photogrammetry, remote tissue sampling, hands-on assessment and individual tracking. We then conducted a workshop to establish the relative utility and feasibility of all these approaches for different groups of marine mammal species. We describe how future marine mammal monitoring programs can be designed to inform population-level analysis.

First long-term record of halogenated organic compounds (AOX, EOX, and PCDD/F) and trace elements (Cd, Cr, Cu, Fe, Hg, Pb, Ni, and Zn) in marine biota of the coastal zone of southcentral Chile

This paper reports long-term concentration records of metals and organic halogenated compounds in tissues of 49 species of marine organisms from Eastern South Pacific coast, Biobio region, Chile during a marine monitoring program developed between 2006 and 2015. Principal component (PCA) and generalized linear model (GLM) analyses indicated significant differences in the concentrations of metals and organic halogenated compounds among taxonomic and functional groups. The strongest relationships exist between species that share similar feeding habits rather than between species of the same taxonomic group or habitat. The significant differences between these groups were maintained over time; thus concentrations detected are, in general, within the ranges reported at genus level for Chile and the rest of the world. Since there is no evidence of any pollution process in the area, this information can be used as an environmental reference to establish natural concentrations for the parameters and organisms analyzed.

Assessing the State of Demersal Fish to Address Formal Ecosystem Based Management Needs: Making Fisheries Independent Trawl Survey Data ‘Fit for Purpose’

In Europe, introduction of the Marine Strategy Framework Directive (MSFD) represents formal, legally-binding, adoption of ecosystem-based management (EBM) across most European waters. Member States of the European Union have invariably nominated their groundfish surveys as part of the marine monitoring programmes required under the MSFD. Groundfish surveys were originally intended to provide fisheries independent abundance indices for commercially valuable species to support fisheries stock assessments and fisheries management. However, early studies, primarily intended to make the case for the need for EBM, exposed these data to a broader range of uses and highlighted various data quality issues. Individual scientists, pursuing personal research agendas, addressed these as each thought best. This informal approach to assuring data quality is not sufficient to support formal assessments of fish species status and fish community status required under legally-mandated EBM, such as the MSFD, because quality audit, formal logging of issues identified, and remedial measures taken, is often lacking. Groundfish survey data, needed to implement legally-mandated EBM, should be subjected to a formal Quality Assurance–Quality Audit (QAQA) process to ensure that they are properly fit for purpose. This paper describes a QAQA process applied European groundfish survey data to ensure their adequacy to support MSFD needs and considers how this process might be taken forward in the future.

Environmental DNA (eDNA) metabarcoding reveals strong discrimination among diverse marine habitats connected by water movement.

While in recent years environmental DNA (eDNA) metabarcoding surveys have shown great promise as an alternative monitoring method, the integration into existing marine monitoring programs may be confounded by the dispersal of the eDNA signal. Currents and tidal influences could transport eDNA over great distances, inducing false-positive species detection, leading to inaccurate biodiversity assessments and, ultimately, mismanagement of marine environments. In this study, we determined the ability of eDNA metabarcoding surveys to distinguish localized signals obtained from four marine habitats within a small spatial scale (<5km) subject to significant tidal and along-shore water flow. Our eDNA metabarcoding survey detected 86 genera, within 77 families and across 11 phyla using three established metabarcoding assays targeting fish (16S rRNA gene), crustacean (16S rRNA gene) and eukaryotic (cytochrome oxidase subunit 1) diversity. Ordination and cluster analyses for both taxonomic and OTU data sets show distinct eDNA signals between the sampled habitats, suggesting dispersal of eDNA among habitats was limited. Individual taxa with strong habitat preferences displayed localized eDNA signals in accordance with their respective habitat, whereas taxa known to be less habitat-specific generated more ubiquitous signals. Our data add to evidence that eDNA metabarcoding surveys in marine environments detect a broad range of taxa that are spatially discrete. Our work also highlights that refinement of assay choice is essential to realize the full potential of eDNA metabarcoding surveys in marine biodiversity monitoring programs.

Monitoring for tipping points in the marine environment

Increasingly studies are reporting sudden and dramatic changes in the structure and function of communities or ecosystems. The prevalence of these reports demonstrates the importance for management of being able to detect whether these have happened and, preferably, whether they are likely to occur. Ecological theory provides the rationale for why such changes occur and a variety of statistical indicators of approach that have generic properties have been developed. However, whether the theory has successfully translated into monitoring programmes is unknown. We searched the literature for guidelines that would drive design of monitoring programmes able to detect past and approaching tipping points and analysed marine monitoring programmes in New Zealand. We found very few guidelines in the ecological, environmental or monitoring literature, although both simulation and marine empirical studies suggest that within-year sampling increases the likelihood of detecting approaching tipping points. The combination of the need to monitor both small and medium scale temporal dynamics of multiple variables to detect tipping points meant that few marine monitoring programmes in New Zealand were fit for that purpose. Interestingly, we found many marine examples of studies detecting past and approaching TP with fewer data than was common in the theoretical literature. We, therefore, suggest that utilizing ecological knowledge is of paramount importance in designing and analyzing time-series monitoring for tipping points and increasing the certainty for short-term or infrequent datasets of whether a tipping point has occurred. As monitoring plays an important role in management of tipping points by providing supporting information for other locations about when and why a tipping point may occur, we believe that monitoring for tipping points should be promoted.