The distribution of floating litter in marine waters, influenced by currents and wind drag, often determines the dispersal of its encrusting fauna. In the present paper, we observed for the first time the colonization of rafting floats from abandoned, lost or derelict fishing gears (ALDFG) by the four protected deep-sea species: Errina aspera, Desmophyllum pertusum, Madrepora oculata Pachylasma giganteum.Overall, 41 floats, colonized by deep benthic species, were found stranded on the shore of the Sicilian coast of the Strait of Messina, between 2016 and 2019. Species composition, number and occurrence of colonizing organisms were analyzed. On the basis of the species composition (the association between E. aspera, P. giganteum and Megabalanus tulipiformis), the knowledge on their ecology, biogeography, path of local currents, it was possible to define that the area of origin of the most part of these fishing net floats was the Strait of Messina.

A bloom of putatively non-indigenous species (NIS) Prorocentrum shikokuense was detected for the first time in the Mediterranean Sea at the Brindisi harbor (Southern Adriatic Sea) on September 2016, in the context of EU Marine Strategy Framework Directive monitoring in the ports. This species is usually observed in the East China Sea and Japanese and Korean waters. In the Brindisi harbor this dinoflagellate reached the concentration 105 cell/L and represented from 30 to 50% of the total phytoplankton population. Besides this event, Prorocentrum shikokuense has not been found blooming until today in Mediterranean waters. This study suggests the necessity to improve the monitoring surveys in areas that are known vulnerable systems to alien and invasive species, such as ports.

This paper qualifies, quantifies and localizes seafloor marine debris (SMD) in the Moroccan portion of the Mediterranean Sea. Six scientific trawl surveys were conducted by the Moroccan Institute of Fisheries Research from 2012 to 2015 between Cape Spartel (5°W) and Saidia (2°W), during which a total of 497 kg of SMD has been collected. Statistical analysis show that the mean abundance differed between surveys, generally ranging from 26 ± 68 to 80 ± 133 kg/km2. A typology of SMD indicates that plastic represented 73% of the debris collected, followed by rubber (12%), textile (8%), metal (3%), glass (0.32%), and some unidentified materials (2.70%). Analysis of results shows that the abundance and the distribution of SMD were strongly influenced by the local anthropogenic activities and by rivers inputs. The movements and accumulations in the open sea were also shown to be influenced by the geomorphology and the hydrodynamics of the basin.

In this study, we used flow cytometry to examine how incubation in dark versus light affects the vitality and viability of UV-irradiated Tetraselmis suecica. High UV doses (300 and 400 mJ/cm²) affected the esterase activity, membrane permeability, and chlorophyll content more when the subsequent incubation took place in light. For non- or low UV dose (100 and 200 mJ/cm²)-treated cells, incubation in light resulted in cell regrowth as compared to incubation in dark. Damaged cells (enzymatically active but with permeable membranes) did not recover when incubated under light or dark conditions.Exposure to light reduces the evaluation time of any given ballast water treatment, as viable cells will be detected at an earlier stage and the vitality is more affected. When evaluating the performance of UV-based ballast water treatment systems (BWTS), these results can be useful for type approval using T. suecica as a test organism in the test regime.

Global aquaculture discharges are typical anthropogenic carbon and nutrient sources to nearby mangrove forests. In this study, we quantified total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP) stocks (0–50 cm) in soils from three sites of Kandelia obovata forests with different shrimp-pond discharge histories of 0, 8 and 14 years (i.e. 0DK, 8DK and 14DK, respectively). Results showed that shrimp pond effluents increased soil TOC densities at 8DK. TP densities gradually increased with discharge histories, whereas TN densities were similar between 8DK and 14DK. Besides, IsoSource analyses demonstrated that the high δ¹³C values of shrimp pond effluents contributed 30.00%–33.60% of mangrove soil TOC at 0–10 cm depth. These results suggested that shrimp pond effluents altered soil TOC, TN and TP stocks and added carbon source to mangrove soils, which was related to discharge histories and soil depth. Moreover, the discharge changed carbon and nutrient patterns, which warrant attention.

Haizhou Bay National Ocean Park is the first national ocean park in China. Consequently, the investigation of the spatial distribution characteristics, source apportionment, and ecological risks associated with heavy metals in this area is of great significance. Twelve sediment samples were collected in October 2016, and the geoaccumulation index (Igeo) method and the potential ecological risk index (PERI) method were used to assess the ecological risk. The results showed that the concentrations of the heavy metals (except Cr and Cu) in the surface sediments of the study area met the primary standard of marine sediment quality (GB18668-2002). The spatial distribution pattern of heavy metals in the surface sediments of Haizhou Bay National Ocean Park featured high concentrations in the southwestern region and low concentrations in the northeastern region, with a gradual decrease with increasing distance offshore, indicating that anthropogenic activities were the main source of heavy metal pollution. The evaluation results of the Igeo and PERI methods showed that Cd was the element posing the greatest ecological risk and that the ecological risk level in Haizhou Bay National Ocean Park corresponded to moderately contaminated. These findings indicate that effective management strategies should be developed to protect the marine environmental quality.

During the 2011 M/V Rena oil spill in Tauranga, New Zealand, 383 little blue penguins (LBP, Eudyptula minor) were oiled, rescued and rehabilitated, with 90.6% surviving to be released back to the wild. We monitored the post-release breeding success of rehabilitated LBPs to assess the effectiveness of the rehabilitation process. Breeding success was monitored during the first breeding season post-release (2012−13) to assess productivity for both rehabilitated and control penguins (breeding pairs of rehabilitated or non-oiled (control) birds). Egg laying, hatching and fledging success rates for pairs of rehabilitated and control penguins were both within ranges reported for other LBP colonies in Australia and New Zealand. The only significant difference between rehabilitated and control pairs was that hatching success was reduced in the first season after release for rehabilitated pairs. Overall, rehabilitation appeared to reverse most potential negative effects of oiling on the post-release breeding success of rehabilitated LBP.

This baseline study highlights the ²¹⁰Po and ²¹⁰Pb concentration in seven macroalgae species from the northern Gulf that are frequently washed ashore during the bloom season from February to April. The highest concentrations of ²¹⁰Po and ²¹⁰Pb were 2.947 ± 0.032 and 1.057 ± 0.145 Bq kg⁻¹ wwt, respectively, in brown algae Sargassum boveanum, and the lowest in green algae Ulva prolifera with 1.533 ± 0.058 and 0.170 ± 0.069 Bq kg⁻¹ wwt, respectively. A ²¹⁰Po enrichment was observed in both brown and green algae species, with the ²¹⁰Po/²¹⁰Pb ratio being >1 for all the samples. The mean concentration of ²¹⁰Po in all species was an order of magnitude higher than ²¹⁰Pb, and the difference in mean concentration is statistically significant (p < 0.001). At the same time, the mean concentration of dissolved ²¹⁰Po and ²¹⁰Pb in seawater was 0.28 ± 0.01 and 0.52 ± 0.01Bq m⁻³ with a ²¹⁰Po/²¹⁰Pb ratio of 0.54 ± 0.02 indicating that ²¹⁰Po was absorbed from water and more concentrated by macroalgae. The measured concentration factor (CF) for ²¹⁰Po in these macroalgae for the northern Gulf varied between 5 × 10³–1 × 10⁴, higher than the IAEA recommended value of 1 × 10³ which suggests that a revision of that value may be needed. The field derived CFs for ²¹⁰Pb vary between 3 × 10²–1.8 × 10³, comparable to the ICRP recommended value of 2 × 10³.

The effects of short-term (7 days) experimental ocean acidification (−0.4 pH units) and warming (+5 °C) on anti-predator defenses of two sympatric Mytilus species from China, M. coruscus and M. edulis, in the presence and absence of predator cues were investigated. Results suggested species-specific independent negative effects of acidification and warming on the number and weight of byssal threads, the force of thread attachment, and total thread plaque area. Similar negative effects were observed for clustering behaviour, with acidification and warming independently increasing the number of solitary individuals and decreasing the percentage of mussels in clusters. Acidification effects on byssus were strongly exacerbated when predators were present. Ultimately, this study suggests that short-term exposure to experimental warming and acidification can negatively impact anti-predator defense strategies in mussels with potential ramifications for predator-prey interactions and ecological functioning in systems where mussel beds play a key ecological role.

We investigated the environmental partitioning and particle characteristics of macro-, meso- and microplastics and their uptake into the mussel, Mytilus edulis. Sediment samples, overlying seawater and mussels from 9 intertidal locations in the South West of England were analysed for abundance and type of microplastic. Micro- and mesoplastic-like particles were found in 88.5% of the 269 mussels sampled, ranging from 1.43 to 7.64 items per mussel. Of these plastic particles, 70.9% were identified as semi-synthetic (mainly modified-cellulose). Mussel microplastic abundance, but not polymer type, was correlated with that of their surrounding sediment, but not with sea-surface microplastic concentration or mussel size for our study sites. We found significant differences in the relative abundance of polymer types and particle sizes between seawater, sediment, and mussels, with mussels over-representing modified-cellulose fibre abundance but under-representing polyvinyl. Mussels contained significantly smaller plastic fragments than their surrounding sediment and shorter fibres than their overlying seawater.