CE10009 Celtic Explorer Cetaceans on the Frontier Cruise North East Atlantic Ocean 2010

This main aim of the survey, led my Galway-Mayo Institute of Technology, was to conduct a habitat specific survey of deep diving cetaceans. The survey was conducted on board the Marine Institute’s R.V. Celtic Explorer as a dedicated survey between 18th February and 1st March 2010. The survey area covered waters over the Porcupine Bank, Porcupine Seabight, Whittard Canyon System and Celtic Shelf. The survey vessel travelled at an average speed of 8 knots while on transect, except in heavy swell. The ship spent from 08:30 – 18:30 each day on visual and acoustic transect, and from 20:30 – 08:30 altered between steaming at 8 knots and being stationary while conducting CTDs (Conductivity Temperature Depth), water sampling and plankton hauls. An acoustic survey was carried out using a towed hydrophone array. Acoustic data from bottlenose dolphin (Tursiops truncatus) encounters were recorded using passive acoustic techniques and provided to a PhD study (based in University College Cork). Visual seabird surveys and megafauna surveys were also conducted on this cruise, as well as the deployment of an argo float. As the primary purpose of the cruise was to record the distribution of cetaceans using visual and acoustic techniques, oceanographic work was conducted only after sunset. 28 oceanographic stations were sampled. Due to the time taken to conduct vertical profiles of zooplankton at some stations, CTDs were not conducted at all stations but at least one CTD was conducted at each canyon/location. CTDs were conducted at 29 stations. Salinity, temperature and fluorescence were measured under way using the ship’s onboard fluorometer and CTD. To conduct a habitat focused, double platform, absolute abundance survey of cetaceans (and marine megafauna, including seabirds) in key habitats for deep-diving species on the slopes and canyon systems of the Porcupine Bank and Sea Bight. To sample the for phytoplankton, zooplankton and krill which form the basis of the food chain which supports cetaceans, seabirds and other marine megafauna in these habitats.