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Draw Polygon Tool

1) Introduction

2) Drawing a Polygon on the Map

3) Using the Edit Tool

4) Analysing the data within your Polygon

5) Other Legend Tools

6) Troubleshooting

1) Introduction

This tool allows you to draw a polygon on a NABIS map page and request a report summarising the commercial catch data taken within the polygon area.  The report returns data for any fishing event where the fisher has reported catch taken within the boundaries of the polygon.  The data returned only relates to those forms which currently have latitude/longitude reporting AND the start point falls within the polygon.

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2) Drawing a Polygon on the Map

1.    Open the NABIS map page. 

2.    Select the 'Draw Polygon' tool from the map tools toolbar (at the top of the map) - your cursor will turn into a cross.

3.    Click a starting point for the polygon on the map page.

4.    Continue to click to add segments to your polygon.

5.    When you are ready to complete the polygon, double-click the last point.  A star will appear at each point you have clicked and the map will show your polygon with a black outline.

You can draw more than one polygon on your map at any time, just re-select the 'Draw Polygon' tool and draw another polygon.  Each polygon will appear separately in the map legend.

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3) Using the Edit Tool

Once the polygon has been drawn you can edit it using the 'Edit' tool in the map legend.  This allows you to edit coordinates, add labels and re-name the polygon.  You can edit each polygon on your map separately through the legend of the polygon.

 a) Editing the points of a polygon

1.    Click on the Map Legend tab

2.    Click on the 'User Polygon' legend item.  This will expand the legend item and give you a number of legend tools.

3.    Click on the 'Edit' legend tool.  This will take you to the Edit User PolygonX (Polygon) page, which shows the latitude and longitude of each point of your polygon.

4.    Click in any of the latitude or longitude fields to edit an individual polygon point.  You can only make changes to the latitude and longitude fields in decimal degree format.  If you have coordinates in degrees decimal minutes or degrees minutes seconds, use the table below to convert your coordinates into decimal format.

5.    You can insert or delete coordinates by using the insert and delete button to the right of the coordinate (note: 'delete' can sometimes be undone by using the browser back button and insert will add a new blank coordinate line above the line you have clicked).

7.     Enter the new coordinates in Decimal degree format (see conversion instructions below).

8.     Click Save to save any changes that you have made and return to the map window.  The map will display any changes that you have made to the coordinates (click cancel and you will return to the map without making any changes).

 Converting from Degrees Decimal Minutes to Decimal Degrees

Converting from Degrees Minutes Seconds to Decimal Degrees

 Note: Although the NABIS polygon editor will ONLY accept points in decimal degrees, it will allow you to enter this in two different formats:

42.23513°S and 175.24365°E OR  -42.23513 and 175.24365

 b) Adding labels to your polygon

1.        Click on the Map Legend tab

2.        Click on the 'User Polygon' legend item.  This will expand the legend item and give you a number of legend tools.

3.        Click on the 'Edit' legend tool.  This will take you to the Edit Polygon page, which shows the latitude and longitude of each point of your polygon.

4.        Click the 'Add Labels' button.

5.        Type labels in the new column that appears alongside your coordinate positions.

6.        Click Save to save your changes and return to the map page - your labels will now be shown on the map.  If you cannot see all of your labels, zoom in slightly (labels will appear only if another label is not overlapping with it, the more you zoom in, the more the labels will spread out).

7.        Click cancel and you will return to the map without making any changes.

 c) Renaming your polygon

1.        You can rename you polygon by typing in the "Layer Title:" text entry box.

2.        Click Save to save your changes and return to the map page - your labels will now be shown on the map.

3.        Click cancel and you will return to the map without making any changes.

 d) Inside NZ Region: 

 This feature helps validate your data, if your coordinates are not formatted for the correct hamispehere then an validation error will occur.

4) Using the Analyse Fishing Tool (MINISTRY OF FISHERIES STAFF ONLY)

Once the polygon has been drawn you can export and map fishing effort data using the 'Analyse Fishing' tool on the map legend.  This allows you to create a buffer, then choose a species and/or method and/or a date range for the data.  You can analyse fishing data for each polygon on your map separately through the legend of the polygon.

NOTE: The data is limited to catch effort data that has been reported using latitude and longitude positions and can also be limited by the accuracy of the positions provided by fishers.

a)Adding a buffer to your polygon

1.        Enter a number in the buffer box and select the unit (kilometres or nautical miles).

2.        Choose the data to analyse, as indicated in the table below.

THEN EITHER:

3.        Click 'Show on Map' to return to the map page and display the data (if a buffer was specified it will now appear on the map around your drawn polygon - every point of the buffer line is drawn 'x' number of nautical miles or kilometres from the edge of your polygon).

OR

3.        Click 'Run Report' - the report will open in the same window.  You can browse through the list that has been generated, or use the 'export' function to export your report into a range of different formats (click the 'select a format' dropdown).

4.     Click 'show on map' from the report page to show the data contained in the report on the map window or click 'proceed to map' to return to the map without adding the points in the report.

OR

3.        Click 'Proceed to Map' and you will return to the map without making any changes.

Data selections for analysis:

An explanation of the fields in the NabisAnalysis.csv file: 

b)  Hiding a buffer 

1.        Once you have returned to the map, click on the Map Legend tab.

2.        Click on the 'User Polygon' legend item.  This will expand the legend item and give you a number of legend tools.

3.        Click on the 'Hide Buffer' legend tool.

4.        The map will refresh and the buffer will now be hidden from the map (note: the buffer is only HIDDEN, if you click 'Analyse', the data within the buffer will still remain in the analysis.

5.        Click proceed to map and you will return to the map without making any changes.

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5) Other Legend Tools

 a) What's Here?

What's Here? can be used to find out the perimeter and area of your polygon and buffer, or to query specific points.  To change the units for linear or area measurements, select the 'Customise' tool (see Customise help for more information).

 b) Remove Layer

To remove the polygon from the map, use the 'Remove Layer' tool as you would with any other layer in NABIS.  You can also un-tick the 'User Polygon' layer within the 'Current Layers' list and click the 'Update Map' button.

 c) Data View

Data view will allow you to export and save the coordinate that you have used to create your polygon (this means that you will be able to load the same polygon again at a later date using the 'Import My Points' tool). 

1. Click on the Map Legend tab.
2. Click on the User Polygon legend item.
3. Click on the 'Data View' legend tool.
4. Click the 'Export' button to save the visible data as a .csv file (for more information see Data View Help).

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 6) Troubleshooting

 a) Error Messages  - Edit Page

 a) Error Messages  - Analyse Page

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