Strandings of NE Atlantic gorgonians

Northeast coral gardens provide vital breeding and feeding habitats for fishes of conservation and commercial importance. Such habitats are increasingly at risk of destruction as a result of over fishing, ocean warming, acidification and marine litter.

A key cause for concern regarding the vulnerability of coral gardens to damage from any source is their slow growth rate, and thereby their ability to recover from damage. Hence protected areas are being put in place, which exclude the use of towed demersal fishing gear.

Citizen scientists observed that gorgonian coral (Pink Sea Fans) skeletons were stranding on beaches entangled in marine debris (sea fangles) across southwest England. Further, SCUBA divers reported that gorgonian corals were being caught up and damaged in lost fishing gear and other marine litter.

To determine the cause of the damage to coral gardens, sea fangles were collected and analysed.

The sea fangles were made up of a diverse range of litter from fishing and domestic sources, however, the majority comprised of fishing gear (P < 0.05).

Marine Protected Areas can protect coral gardens from direct fishing pressure, but risks still remain from ghost fishing pressure, demonstrating the need for sources of litter into the environment to be reduced and existing litter removed.

The EU Marine Strategy Framework Directive (MSFD) outlines targets for marine litter by 2020. This study highlights the importance of adhering to the MSFD and/or creating more ambitious regulation if the UK re-write existing legislation following BREXIT.

E.V. Sheehan, A. Rees, D. Bridger, T. Williams, J.M. Hall-Spencer, Biological Conservation, Volume 209, May 2017, Pages 482–487

The article

Transboundary movement of marine litter in an estuarine gradient: Evaluating sources and sinks using hydrodynamic modelling and ground truthing estimates

Marine debris’ transboundary nature and new strategies to identify sources and sinks in coastal areas were investigated along the Paranaguá estuarine gradient (southern Brazil), through integration of hydrodynamic modelling, ground truthing estimates and regressive vector analysis. The simulated release of virtual particles in different parts of the inner estuary suggests a residence time shorter than 5 days before being exported through the estuary mouth (intermediate compartment) to the open ocean. Stranded litter supported this pathway, with beaches in the internal compartment presenting proportionally more items from domestic sources, while fragmented items with unknown sources were proportionally more abundant in the oceanic beaches. Regressive vector analysis reinforced the inner estuarine origin of the stranded litter in both estuarine and oceanic beaches. These results support the applicability of simple hydrodynamic models to address marine debris’ transboundary issues in the land-sea transition zone, thus supporting an ecosystem transboundary (and not territorial) management approach.

Allan Paul Krelling, Mihael Machado Souza, Allan Thomas Williams, Alexander Turra, Marine Pollution Bulletin, Volume 119, Issue 1, 15 June 2017, Pages 48–63

The article

Effects of dietary polyvinylchloride microparticles on general health, immune status and expression of several genes related to stress in gilthead seabream (Sparus aurata L.)

It is a long-recognized fact that marine plastic debris contaminates the oceans and seas of the entire world. Even though their effects on the aquatic biota are not well documented or understood. The effects of dietary polyvinylchloride microparticles (PVC-MPs) on the general health, immune status and some stress markers were studied using gilthead seabream (Sparus aurata) as a model of marine fish. Thirty specimens were randomly placed in three running sea water aquaria and fish in each aquarium received an experimental diet containing 0 (control), 100 or 500 mg kg−1 of PVC-MPs for 30 days. Metabolic parameters in serum indicated that the dietary intake of PVC-MPs negatively affected several vital organs. Humoral immune parameters were determined in serum and skin mucus. Cellular immune parameters were determined in head-kidney leucocytes. Concomitantly, the expression of different genes related to stress was studied in head-kidney and liver. Regarding head-kidney gene expression, prdx5 was significantly decreased by PVC-MPs intake for 15 and 30 days, respect to the values found in control fish. On the other hand, the expression of prdx1 and prdx3 were significantly increased by the PVC-MPs intake during 15 and 30 days, compared with the values found in control fish. Furthermore, the expression of hsp90 and ucp1 genes decreased and increased, respectively, in the liver of fish fed 500 mg kg−1 of PVC-MPs for 30 days. Although ingestion of PVC-MPs provoked few significant effects (mostly increases) in the main immune activities of gilthead seabream compared with the values found in control fish, PVC-MPs are recognized by the fish as stressors. Continued exposure of fish to high concentrations of PVC-MPs could have a negative impact on fish physiology due to the chronic stress produced.

Cristóbal Espinosa, Alberto Cuesta, María Ángeles Esteban, Fish & Shellfish Immunology, Available online 3 July 2017, In Press

The article

SEM/EDS and optical microscopy analyses of microplastics in ocean trawl and fish guts

Microplastic particles from Atlantic and Pacific Ocean trawls, lab-fed fish guts and ocean fish guts have been characterized using optical microscopy and SEM/EDS in terms of size, morphology, and chemistry. We assessed whether these measurements could serve as a rapid screening process for subsequent identification of the likely microplastic candidates by micro-spectroscopy. Optical microscopy enabled morphological classification of the types of particles or fibers present in the sample, as well as the quantification of particle size ranges and fiber lengths. SEM/EDS analysis was used to rule out non-plastic particles and screen the prepared samples for potential microplastic, based on their element signatures and surface characteristics. Chlorinated plastics such as polyvinyl chloride (PVC) could be easily identified with SEM/EDS due to their unique elemental signatures including chlorine, as could mineral species that are falsely identified as plastics by optical microscopy. Particle morphology determined by optical microscopy and SEM suggests the fish ingested particles contained both degradation fragments from larger plastic pieces and also manufactured microplastics. SEM images of microplastic particle surfaces revealed characteristic cracks consistent with environmental exposure, as well as pigment particles consistent with manufactured materials. Most of the microplastic surfaces in the fish guts and ocean trawls were covered with biofilms, radiolarians, and crustaceans. Many of the fish stomachs contained micro-shell pieces which visually resembled microplastics.

Zhong-Min Wang, Jeff Wagner, Sutapa Ghosal, Gagandeep Bedi, Stephen Wall, Science of The Total Environment, Volumes 603–604, 15 December 2017, Pages 616–626

The article

Monitoring of styrene oligomers as indicators of polystyrene plastic pollution in the North-West Pacific Ocean

Styrene oligomers (SOs) as global contaminants are an environmental concern. However, little is known on the distribution of SOs in the ocean. Here, we show the distribution of anthropogenic SOs generated from discarded polystyrene (PS) plastic monitored from the coastal ocean surface waters (horizontal distribution) and deep seawaters (vertical distribution) in the North-West Pacific Ocean. SOs concentrations in surface seawater and deep seawater ranged from 0.17 to 4.26 μg L−1 (total mean: 1.48 ± 1.23 μg L−1) and from 0.31 to 4.31 μg L−1 (total mean: 1.32 ± 0.87 μg L−1), respectively. Since there is no significant difference in the mean concentrations, SOs seems to be spread across marine environment selected in this study. Nevertheless, regional SOs appears to persist to varying degrees with their broad horizontal and vertical distribution in the ocean. Each horizontal and vertical distribution of SOs differs by approximately 1.95–2.57 times, probably depending on the events of weather and global ocean circulation. These results provide the distribution pattern of SOs for assessing environmental pollution arising from PS plastic.

Bum Gun Kwon, Keiji Amamiya, Hideto Sato and al., Chemosphere, Volume 180, August 2017, Pages 500–505

The article

Microplastics shedding from polyester fabrics

To minimize microplastics from polyester fabrics getting in the ocean, and posing a threat to the marine environment, the production design of polyester fabrics needs to change. Mistra Future Fashion now release new findings where their researchers and industry partners have investigated the relation between fabric properties and shedding for polyester fabrics, and thereby contribute to fill current research gap. (…) (Mistra Future Fashion, 15/06/2017)

The report

Plastic pollution in the Antarctic worse than expected

The continent is considered to be a pristine wilderness compared to other regions and was thought to be relatively free from plastic pollution. However new findings by scientists from University of Hull and British Antarctic Survey (BAS) have revealed that recorded levels of microplastics are five times higher than you would expect to find from local sources such as research stations and ships. (…) (bas.ac.uk, British Antarctic Survey, 19/06/2017)

The news

The study