Annual underwater television (UWTV) survey of abundance and distribution of Nephrops in the Celtic Sea Nephrops Grounds. The prawn (Nephrops norvegicus) are common in the Celtic Sea occurring in geographically distinct sandy/muddy areas where the sediment is suitable for them to construct their burrows. The Celtic Sea area supports a large multi-national targeted Nephrops fishery mainly using otter trawls. This survey was carried out by the Marine Institute on board the R.V. Celtic Voyager in July 2017 in the Celtic Sea. Underwater television surveys and assessment methodologies have been developed to provide a fishery independent estimate of stock size, exploitation status and catch advice. 1.To obtain 2017 quality assured estimates of Nephrops burrow densities from a randomised isometric grid of UWTV stations at 4 nautical mile spacing over the known spatial a bathymetric distribution of the Smalls Nephrops Stock (FU22). 2.To obtain 2017 quality assured estimates of Nephrops burrow densities from a randomised isometric grid of UWTV stations at 6 Nmil on the Labbadie, Cockburn and Jone's Banks (FU20&21). 3. To obtain 2017 quality assured estimates of Nephrops burrow densities within the known spatial a bathymetric distribution of the Nephrops Stock off the south coast of Ireland (FU19). 4.To collect ancillary information from the UWTV footage collected at each station such as the occurrence of sea-pens, other macro benthos and fish species and trawl marks on the sea bed. 5.To collect oceanographic data using a sledge mounted CTD. 6.To sample Nephrops and macro benthos using a 4 m beam trawl deployed at ~10 stations on the Smalls.