This study documented the levels of microplastics in three commercially important small pelagic fish species in South African waters, namely European anchovy (Engraulis encrasicolus), West Coast ...round herring (Etrumeus whiteheadi) and South African sardine (Sardinops sagax). Data suggested variation between species with a higher concentration of microplastics for S. sagax (mean of 1.58 items individual-1) compared to Et. whiteheadi (1.38 items individual-1) and En. encrasicolus (1.13 items individual-1). The occurrence of microplastics was also higher for S. sagax (72%) and Et. whiteheadi (72%) compared to En. encrasicolus (57%). Microfibres accounted for 80% of ingested microplastics (the remainder were plastic fragments) with the main ingested polymers being poly(ethylene:propylene:diene) (33% occurrence), polyethylene (20%), polyamide (20%), polyester (20%) and polypropylene (7%). The abundance of ingested items was not significantly correlated with fish caudal length or body weight, and spatial investigation indicated an increase in the abundance of ingested items from the West to the South coast. Etrumeus whiteheadi is proposed as a bio-indicator for microplastics for South Africa.
The identification of microplastic hotspots is vital to our long-term understanding of their environmental fate and distribution. Although case studies have increased globally, sampling campaigns are ...often restricted geographically, with poor spatial resolution. Here, we use citizen science to increase our geographical reach, which improved our understanding of microplastic distribution in estuarine and beach sediment along the south-west coast of England. Hotspots (>700 particles per kg dry sediment) were identified on the Scilly Islands and in close proximity to major metropolitan hubs (i.e. Falmouth and Plymouth). Particles extracted from the Scilly Island sites were composed of polyethylene and polypropylene. With low population density on the Isle of Scilly, hotspots may suggest that microplastics originate from distant sources, while Falmouth and Plymouth, on mainland UK, are locally supplied. This information supports the design of future campaigns and targeted mitigation strategies in areas of highest concentrations.
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•Hotspots (>700 particles per kg dry sediment) were detected on the Scilly Islands.•Microplastic hotspots were also associated with major metropolitan hubs.•Distant and local sources were discussed.
Invasive non‐native species (NNS) are internationally recognized as posing a serious threat to global biodiversity, economies and human health. The identification of invasive NNS is already ...established, those that may arrive in the future, their vectors and pathways of introduction and spread, and hotspots of invasion are important for a targeted approach to managing introductions and impacts at local, regional and global scales. The aim of this study was to identify which marine and brackish NNS are already present in marine systems of the northeastern Arabia area (Arabian Gulf and Sea of Oman) and of these which ones are potentially invasive, and which species have a high likelihood of being introduced in the future and negatively affect biodiversity. Overall, 136 NNS were identified, of which 56 are already present in the region and a further 80 were identified as likely to arrive in the future, including fish, tunicates, invertebrates, plants and protists. The Aquatic Species Invasiveness Screening Kit (AS‐ISK) was used to identify the risk of NNS being (or becoming) invasive within the region. Based on the AS‐ISK basic risk assessment (BRA) thresholds, 36 extant and 37 horizon species (53.7% of all species) were identified as high risk. When the impact of climate change on the overall assessment was considered, the combined risk score (BRA+CCA) increased for 38.2% of all species, suggesting higher risk under warmer conditions, including the highest‐risk horizon NNS the green crab Carcinus maenas, and the extant macro‐alga Hypnea musciformis. This is the first horizon‐scanning exercise for NNS in the region, thus providing a vital baseline for future management. The outcome of this study is the prioritization of NNS to inform decision‐making for the targeted monitoring and management in the region to prevent new bio‐invasions and to control existing species, including their potential for spread.
This review identifies and risk screens potentially invasive non‐native species (NNS) within the Regional Organization for the Protection of the Marine Environment Sea Area. In total, 136 NNS were identified, of which 56 are already present and a further 80 were identified as likely to arrive in the future.
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