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The term vulnerable marine ecosystem (VME) was introduced to facilitate the spatial management of deep-seas, identifying those habitats vulnerable to anthropogenic disturbance, such as trawling. Consistent interpretation of the VME definition has been hampered by an underlying paucity of knowledge about the nature and distribution of deep-sea habitats. Photographic and video platforms yield data rich, quantifiable imagery to address these knowledge gaps. A low-cost towed benthic video sled has been used to investigate deep-sea habitats and trawling impacts in west Greenland. A review of imagery from multiple cruises highlighted an area where benthic megafauna contributes to notable structural complexity on the continental slope of the Toqqusaq Bank. Quantitative analysis of imagery from this area provides the first description of a soft coral garden habitat and other communities. The coral garden and observed densities are considered in relation to the VME guidelines (FAO, 2009) and wider literature. The study proposes a 486 km 2 area spanning ∼60 km of continental slope as a VME. This has direct implications for the management of economically important deep-sea trawl fisheries, which are immediately adjacent. This furthers our knowledge and understanding of VMEs in North Atlantic, in a previously understudied region and demonstrates the utility of a low-cost video sled for identifying and describing VMEs.

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Solar radiation is a crucial factor governing biological processes in polar habitats. Containing harmful ultraviolet radiation (UVR), it can pose a threat for organisms inhabiting surface waters of polar oceans. The present study investigated the physiological color change in the obligate sympagic amphipod Apherusa glacialis mediated by red-brown chromatophores, which cover the body and internal organs of the species. Short-term experimental exposure to photosynthetic active radiation (PAR) led to pigment dispersal in the chromatophores, resulting in darkening of the animal. Irradiation in the PAR range (400-700 nm) was identified as the main trigger with high light intensities evoking marked responses within 15 min. After exposure to high PAR, darkness led to a slow aggregation of pigments in the cell center after 24 h. Experiments revealed no statistically significant change in coloration of the animal when exposed to different background colors nor UV radiation. Our results point to a doseand time-dependent photoprotective role of chromatophores in the amphipod, presuming a shielding effect from harmful radiation in a dispersed state. The reversible nature of the physiological color change enables the species to adapt dynamically to prevailing light conditions and thereby minimize the cost of increased conspicuousness toward visually hunting predators.