Commercial FISHING EFFORT Tool
Introduction
Using the 'Commercial Fishing Effort' Tool
Commercial Fishing Effort Legend
Obtaining Effort Figures
Introduction
The 'Commercial Fishing Effort' tool is used to display a summary of the fishing effort undertaken to catch commercial species in New Zealand waters. For the purposes of this tool effort is calculated by number of days fished, per vessel.
Commercial fishing effort comes from reports by commercial fishers, the data is validated and then stored in the Ministry of Fisheries Catch Effort database. The data is extracted from the Catch Effort database and displayed on NABIS using the relevant statistical area maps. Each statistical area is shaded by the amount of fishing effort for the selected vessel size(s), fishing method(s), month(s), and fishing year(s). Darker shades show where there was more effort and lighter shades show where there was less effort. The map legend states the effort range for each shade. To ensure the data is validated and complete, effort data is only available on NABIS up to the last 3 - 6 months.
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Using the 'Commercial Fishing Effort' Tool
Select 'Commercial Fishing Effort' from the 'Layer Generation tools' within the 'Select Layers' tab. A new page appears with drop down lists showing the fields in the table below for you to choose from. To select more than one item from a list, hold down the 'Ctrl' key and click each item required:
| Field Name |
Function |
| Vessel size |
Data can be restricted by a vessel size class. Select one or more vessel lengths classes. |
| Method |
Data can be restrictied by fishing method. Select one or more. |
| Year Type |
Data can be restricted by year. Select what type of year you would like to display the commercial fishing effort data by. Choose either fishing year or calendar year. |
| Year Range |
When Fishing Year is selected the pick list shows fishing years (standard fishing years are from 1 October to 30 September) i.e. 2007/2008. Choose one or more fishing years.
When Calendar Year is selected the pick list shows full calendar years i.e. 2008. Choose one or more calendar years. |
| Month |
Data can be restricted by month. Select one ore more months. |
NOTE: Letter selections for skipping through lists works differently depending on the browser being used. For Internet Explorer 6 typing "a", "a" will go to the second "a" in the list. For internet explorer 7 "a", "a" will go to a word beginning with "aa...".
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Requested Breaks
Requested Breaks lets you choose the number of breaks that the data will be displayed in. Breaks represent the approximate number of ranges the data will be broken down into. You can choose up to 10 requested breaks but it is suggested that 4 or 5 are optimum so you can easily view the differences in shading between ranges.
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How do I Interpret the Commercial Fishing Effort Legend?
Data Unreliable
Where 75% or more of the fishing effort in one area is from a single record, the data is not displayed because it is considered to be too unreliable.
Data Withheld
Where the fishing effort in the area is from fewer than 3 vessels or companies, the data is not displayed outside the Ministry of Fisheries because it is considered to be commercially sensitive.
No Effort Reported
Where there are no records of effort in the area for this time period, the data is displayed as 'No Effort Reported'.
Effort Range Boxes
The legend shows a number of fishing effort ranges with each different effort range associated with a different colour on the map. The darker the colour, the greater the effort in that area. The number of effort range boxes in the legend depends on the number of 'Requested Breaks' you have selected.
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How do I get the actual fishing effort figures?
'What's Here?' tool
Select the 'What's Here?' tool from the Layer tools in the legend box for the commercial fishing effort map. Click on a statistical area of interest. The commercial fishing effort information for the statistical area is displayed in a new page. The total estimated number of day fished for the selected vessel size(s), method(s), statistical area and time period is displayed in the 'est_no_days_fished' row, it is in days fished per vessel. For areas where the data is not displayed the 'est_no_days_fished' row will indicate either "Data unreliable", or there is a "-1" in the 'data_error' row.
See 'What's Here?' for more information about this tool.
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