CE19008 MOnitoring CHAnge in Submarine CANyon Coral Habitats (MoCha_SCan) Leg 1North East Atlantic Ocean 2019

This 11 day survey led by University College Cork took place in May 2019 on board the RV Celtic Explorer in the North West Atlantic Ocean off the continental shelf. This survey focused on the maiden deployment of a number of novel, ROV-adapted lander systems in the Porcupine Bank Canyon (PBC) coral habitats, NE Atlantic. Cold water corals (CWCs) flourish on the Irish-Atlantic margin between 600 and 100 m water depth, where they form a number of structural habitat types (coral reefs, mounds and gardens). Recent research shows that deep water habitats, including CWC habitats on the Irish margin, may be impacted by recent environmental change. The main objectives of this survey are: a) to deploy 8 new lander systems within a range of coral habitats throughout the PBC; b) to complete mapping coverage within the PBC; c) to sample the coral, sediment and ambient watermass around the lander sites and; d) to sample particulate organic matter around key coral habitats. Data recorded via landers from each habitat will allow to determine the controls on habitat variability. Furthermore, this data can be used as a baseline to which later deployments at this site will be used to compare against. Completed canyon coverage will feed into a number of multiscale mapping projects including the H2020 project “Integrated Assessment of Atlantic Marine Ecosystems in Space and Time” (iATLANTIC) and the SFI-, GSI- and MI-funded “Mapping, Modelling and Monitoring Key Processes and Controls on Cold Water Coral Habitats in Submarine Canyons” (MMMonKey_Pro) programme. Video data will be used to characterise key coral habitat within the canyon and subsequesntly, HD DEM’s will be generated as a central dataset for the multiscale projects listed above. 1. To define high-resolution (1 - 20 m) temporal and spatial distribution of benthic boundary layer hydrodynamics processes influencing the canyon and associated habitats over a 3 month period (May - August). 2. To determine contemporary spatial and temporal sediment supply and distribution to the canyon and associated habitats (May - August). 3. To determine the specific factors controlling the type of habitat formed by cold water corals and associated organisms. 4. To determine active sedimentary processes within the Porcupine Bank Canyon, the furtherest westward canyon in Europe. 5. To determine the potential influence of nearby industrial impact (i.e. fisheries sediment plumes) on deep water benthic habitats. 6. To determine the anthropogenic finger print in suspended/contempory sediments (microplastics/faecal matter/pollutants) in deep water habitats offshore Ireland. 7. To generate a series of recommendations for site surveys by industrial activities to ensure responsible practice. 8. To determine the health status (diseases) of cold water corals in the Porcupine Bank Canyon. 9. To understand threshold and boundary conditions of cold water coral habitats. 10. To extend INFOMAR's spatial coverage of the Irish deepwater EEZ. During the survey 8 landers were deployed and 20 ROV dives took place. Water samples and push cores were taken at several of the lander sites. Multibeam seabed mapping of a wreck took place during the survey also.