Commercial trawl fishing data were provided by Ministry for Primary Industries to determine where fishing effort had taken place. Data were from Trawl Catch Effort Returns (TCER) and Trawl Catch Effort and Processing Returns (TCEPR) and included effort for flatfish, barracouta, snapper, red cod, and red gurnard. Data cover the time period 1 October 2008 to 16 November 2011. Where trawl data had only start tow positions (TCER data), trawl lines were generated on groomed data by plotting lines between consecutive trawl start positions, per vessel, per day (data excludes single trawls that fell on the same day). The Line Density Tool in ARCInfo vers. 10.0 was used to interpolate trawl tracklines giving each line a weight based on the estimated area towed. A geoTIFF shows the distribution of the density of trawl tracks.