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Sea pen communities are United Nations General Assembly-designated Vulnerable Marine Ecosystems which occur worldwide in soft-bottom sediments where trawling often occurs. However, the ability of marine managers to assess, monitor and mitigate impacts to sea pens at national scales has been constrained by a limited understanding of their environmental requirements, geographical distribution and responses to trawling. In this study, we used random forest species distribution modelling (SDM) to predict the distribution of suitable habitat for 3 sea pen species (tall sea pen Funiculina quadrangularis, slender sea pen Virgularia mirabilis and phosphorescent sea pen Pennatula phosphorea) on the UK continental shelf, exploring the results relative to the distribution of fishing activity. Occurrence of all 3 species corresponded to areas of low current and wave velocity, where suspended matter in the water column was also low. However, for F. quadrangularis, the largest species, the models indicated substantially different drivers of distribution between the Greater North Sea and Celtic Seas ICES Ecoregions. This disparity appears to reflect modification to the range and realised niche of this species in the Greater North Sea, due to trawling impacts. P. phosphorea and V. mirabilis appear to be more resilient to trawling, with no clear negative relationships observed. Our findings illustrate the value of broadscale qualitative comparisons between SDMs and human activity data for insights on pressure-state relationships. When combined with robust distribution maps, this improved understanding of vulnerability will enable marine managers to make ecologically sound, defensible decisions and deliver tangible conservation outcomes for sea pen communities.

The management of reef-associated fish species is challenging due to their life history characteristics and occurrence in rocky reef habitats that are difficult to sample using traditional sampling gears. We compared 2 common sampling gears for reef fish species, chevron traps and underwater video, using 5 yr of comprehensive paired sampling data (N = 7034) collected at reef habitats between North Carolina and Florida along the southeast United States Atlantic continental shelf. Most fish families (80%) and species (85%) were observed significantly more often on video than caught in traps, and only 2 species out of 40 (5%)—black sea bass Centropristis striata and bank sea bass C.ocyurus—were caught significantly more often in traps than observed on video. Moreover, site-specific species richness was approximately 3-4 times higher on average for video compared to traps. We also used a generalized additive model to show that the ratio of trap-caught species to video-observed species was higher in shallower waters off North and South Carolina, especially when water clarity was low. Results demonstrate that video can be an efficient gear to sample most reef fishes around the world but may provide even greater benefits when paired with traditional sampling gears like traps to leverage the strengths of each gear for estimating relative abundance and species richness with more certainty.

In this study, we analysed the structure and functioning of the Portuguese continental shelf ecosystem and investigated the role of sardine Sardina pilchardus using the Ecopath massbalance approach. An Ecopath model was configured to represent the continental shelf waters in the period 2006-2009. The model showed that biomass was concentrated in low and intermediate trophic levels as in other upwelling areas. Several low- and medium-trophic-level groups were identified as dominant groups in the ecosystem (e.g. zooplankton, macrozoobenthos, sardine, chub mackerel Scomber colias, and demersal and benthopelagic invertivorous fish). Furthermore, lowtrophic-level groups were responsible for the main energy flows, and overall higher impact on the ecosystem, emphasizing the importance of bottom-up control of the ecosystem structure. Our results are relevant to understand structure and functioning of this ecosystem and constitute an important step towards an ecosystem approach to fisheries management in the study area. PROMAR project (CERTIFICA) [3103-01-FEP-0032] EU/DG Fisheries Data Collection Regulation, LIFE+ [MarPro. NAT/PT/000038] EEA Grants (SafeSea) [0039] 'Fundacao para a Ciencia e Tecnologia (FCT)Portuguese Foundation for Science and Technology [PD/BD/114540/2016] ARDITI (Regional Agency for Development of Research, Technology and Innovation of Madeira) [M1420-09-5369-FSE-000001]