Plastic pollution is globally recognised as a threat to marine ecosystems, habitats, and wildlife, and it has now reached remote locations such as the Arctic Ocean. Nevertheless, the distribution of microplastics in the Eurasian Arctic is particularly underreported. Here we present analyses of 60 subsurface pump water samples and 48 surface neuston net samples from the Eurasian Arctic with the goal to quantify and classify microplastics in relation to oceanographic conditions. In our study area, we found on average 0.004 items of microplastics per m3 in the surface samples, and 0.8 items per m3 in the subsurface samples. Microplastic characteristics differ significantly between Atlantic surface water, Polar surface water and discharge plumes of the Great Siberian Rivers, allowing identification of two sources of microplastic pollution (p < 0.05 for surface area, morphology, and polymer types). The highest weight concentration of microplastics was observed within surface waters of Atlantic origin. Siberian river discharge was identified as the second largest source. We conclude that these water masses govern the distribution of microplastics in the Eurasian Arctic. The microplastics properties (i.e. abundance, polymer type, size, weight concentrations) can be used for identification of the water masses.

No abstract

No abstract

Invertebrate Biology 133(3): 261-273.

No abstract

Seawater properties in two intense rings in the South Atlantic are considered. One ring separated from the Brazil Current and the other from the Malvinas Current. The analysis is based on the CTD casts and SADCP measurements from the onboard velocity profiler. The optical properties, chemical parameters, methane concentration, and biological properties such as primary production, plankton, and fish were also analyzed. Analysis of strong differences between the eddies is supplemented by observations of whales and birds in the region.

A new myzostome species, described here as Myzostoma khanhkhoaensis sp. nov., was collected in Nhatrang Bay, central Vietnam, during investigation of symbionts associated with crinoids. Myzostoma khanhkhoaensis sp. nov. was found only on Clarkcomanthus albinotus Rowe, Hoggett, Birtles & Vail, 1986 in dense groups of up to 25 specimens. This species closely matches the colour pattern of the host by adjusting its cryptic colour and infects the distal part of crinoid arms, causing them to become curved. This is the first record of myzostomes that induce deformation of skeletal elements without the formation of galls or cysts. Morphologically M. khanhkhoaensis sp. nov. is close to M. cuniculus and M. pseudocuniculus but clearly differs from both of them by the shape of caudal blade and chaetae. Molecular-genetics analysis based on CO1, 16S and 18S DNA placed M. khanhkhoaensis sp. nov. in a clade including M. cuniculus, M. pseudocuniculus and M. indocuniculus.

Biofouling of artificial substrates is a well-known phenomenon that can negatively impact offshore industry operations as well as data collection in the ocean. Fouling communities worldwide have mostly been studied within the top 50 m of the ocean surface, while biofouling below this depth remains largely underreported. Existing methods used to study biofouling are labor intensive and expensive when applied to the deep sea. Here, we propose a simple and cost-effective modification of traditional methods for studying biofouling by mounting test plates on autonomous seafloor equipment and preserving them in ethanol upon retrieval for transport to the laboratory. This method can greatly advance our understanding of biofouling processes in the deeper ocean, including fouling community biodiversity, recruitment, and seasonality. We present two case studies from the Laptev Sea and the Sea of Okhotsk in support of this method. In the first study, we looked at fouling communities on the surfaces of ocean-bottom seismometers deployed for one year in the 36–350 m depth range. In the second study, we tested metal and plexiglass (poly(methyl methacrylate) plates mounted on autonomous bottom stations and found evidence of both micro- and macrofouling after three months of deployment. Our results demonstrate that various autonomous seafloor equipment can be used as supporting platforms for biofouling studies.