Description: <DIV STYLE="text-align:Left;font-size:12pt"><P><SPAN>The distribution of total commercial catch is estimated for all fishing events reported in statutory catch and effort returns for the period 1 October 2007 to 30 September 2019.</SPAN></P><P><SPAN /></P><P><SPAN>The location of fishing events is reported by either start (or start and end) coordinates (precise to 1 nautical mile) or by large statistical areas.</SPAN></P><P><SPAN /></P><P><SPAN>The total catch of all species from each fishing event is spread uniformly over a polygon of space estimated to be occupied by that fishing.</SPAN></P><P><SPAN /></P><P><SPAN>Trawl fishing polygons are derived from the length and width of the door-spread for the duration of the tow.</SPAN></P><P><SPAN>The path of each tow is taken as a straight line between start and end coordinates where these are reported, or between start and estimated end coordinates. Where not required to report end coordinates, (as is the case for most inshore trawling) tow end points are derived using the direction of the next tow start position or the direction of the landing point for the last tow of the day.</SPAN></P><P><SPAN /></P><P><SPAN>Line fishing is attributed to a circle with the center at the reported start position and a radius of the reported length of line set.</SPAN></P><P><SPAN /></P><P><SPAN>Set net fishing is attributed to a circle with the center at the reported start position and radius of 2 nm in accordance with the definition of a single set netting event prescribed in reporting regulations.</SPAN></P><P><SPAN /></P><P><SPAN>Jig fishing reports a single nightly position and is assumed to occur within 5 nm of that position.</SPAN></P><P><SPAN /></P><P><SPAN>Hand and Pot fishing reports by statistical area, and where available, information on habitat and depth or information supplied by fishers is used to define the parts of each statistical area where each type of fishing is likely to have occurred.</SPAN></P><P><SPAN /></P><P><SPAN>In the case of lobster potting and paua diving, an informal map of reef area supplied by the Department of Conservation is used to estimate where this fishing may have occurred.</SPAN></P><P><SPAN /></P><P><SPAN>Catch intensity (kg/ha) is mapped to a square kilometre grid for all fishing events and summed over gear types. The data is aggregated into grid squares of between 1 and 2500 km2 as required to give 12-year annual averages of data from at least three permit holders. Catch per unit area values are classified into ten intensity classes.</SPAN></P><P><SPAN /></P><P><SPAN>MPI has high confidence in the data on catch quantities used to create this data but the spatial distributions of those catches are only approximate and should be used with caution especially at large map scales (maps of small spatial extent). Nevertheless, the aggregation of a large number of fishing events tends to provide consistent patterns that have passed scrutiny when tested with groups of fishers.</SPAN></P><P><SPAN /></P><P><SPAN>Grid squares with less than 3 permit holders present have removed in order to confidentialise the data. </SPAN></P><P><SPAN /></P><P><SPAN>The data has been approved for public release by the data owner, Team Manager, Fisheries Data Management as permit holders and catch values have been aggregated as part of the confidentialisation process and to align with MPI's commitment to promote open data.</SPAN></P><P><SPAN>Please contact the data owner for any questions in relation to the release of this data ([email protected]). </SPAN></P><P><SPAN /></P><P><SPAN>The data custodian for this data is the Spatial Intelligence team ([email protected]). </SPAN></P><P><SPAN /></P><P><SPAN>This data is also displayed on the MPI website as the commercial fishing intensity map.</SPAN></P><P><SPAN /></P><P><SPAN>Last updated: 9 June 2022</SPAN></P></DIV>
Service Item Id: 2d7fca83f1e44aa68134b58d9704b4a4
Copyright Text: Ministry for Primary Industries (MPI) - Manatū Ahu Matua