Nephrops Underwater TV...

Nephrops norvegicus are common around the Irish coast, occurring in geographically distinct sandy or muddy areas where the sediment is suitable for construction of their Burrow dwellings. The Marine Institute carries out Underwater TV surveys annually of commercially important Nephrops stocks. This Dataset provides quality assured estimates of Nephrops Burrow densities from a randomised isometric grid of underwater television (UWTV) stations at six nautical mile spacing over the known Spatial and bathymetric distribution of the FU (functional unit) 16: Porcupine Bank (illustrative shapefile provided with data). Underwater TV Survey reports for this Nephrops stock are available at: http://hdl.handle.net/10793/1431 Also available is the ICES Cooperative Research Reports which details use of UWTV surveys to assess Nephrops stocks. https://tinyurl.com/ices-nephrops This Dataset covers the period of 2012 and is ongoing. One hundred percent of the survey grid was covered in all years but 2012, where sixty-nine percent of the grid was covered (47 stations), and 2015, where no survey data are available due to research vessel breakdown. Dataset fields are Nephrops Functional Unit Number; Survey Code; Year; UWTV station number; Date-Start of UWTV track; Time_Start of UWTV track; Date-End of UWTV track; Time_End of UWTV track; Deimalised Longitude and Latitude midpoint of the UWTV station track; Adjusted density (Nephrops burrows/m²);Length in metres of the UWTV station track; Field of View of camera system in metres; Total Nephrops Burrow count; Fishing Ground Name Nephrops; Source of positional data to calculate UWTV station track (USBL Sed GPS, SHIP GPS, Layback, estimated GPS); Camera system used (SD = standard analogue system, HD = high definition system); Data extraction method (SQL, MSAccess); Data Status (Final for analysis); Research Vessel Name; Correction Factor (Density/Correction Factor = Adjusted Density) and depth (metres).