WLF 448: Fish & Wildlife Population Ecology
Lab Notes 2, Fall 2007

In-class Exercise #2 (Lab 2):

Mapping a Species' Distribution

We will be using a program called ArcView for this exercise. ArcView is the user interface to ARC/INFO, a powerful albeit non-user friendly Geographic Information System. ArcView is useful for such tasks as data display and data query, assuming a database is already available. Although ArcView is supposed to be user friendly, it will take some time for you to get used to its format. Consequently, we have provided the following step-by-step instructions to help you work through today's exercise and the associated problem set.

I. Copy files from class directory to your personal directory:

II. How to access ArcView from the UI computer labs:

  1. Log on to the Novell network

  2. Click on the Start Menu; Analytical Software; ArcView 3.3; ArcView 3.3

  3. Open the program.  This may take awhile, depending on the server's workload.

III. How to display map coverages and their attribute data:

  1. Click on "File" in the main menu and select "New Project." (will happen automatically when you first open the program)

  2. Click on "Views" in the project window if it is not framed, and click on "New" (will happen automatically when you first open the program)

  3. Click on "View" in the ArcView main window and select "Add Theme" (will happen automatically when you first open the program)

  4. In the next window, click on "Drives" in the lower part of the window and select "h:\ or d:\ or ZIP drive"

  5. Double-click on "Arcmaps" (assuming you copied or created the subdir arcmaps)

  6. Themes (map coverages or layers) are listed on the left side of the add theme window. Double-click on "Bailey." The theme name will appear in the view window with a check box.

  7. Click on the check box next to Bailey (Bailey's ecoregions for the western U.S.) and the map coverage should appear.

  8. Double-click on the symbol under Bailey and the Legend Editor window appears.

  9. In the Legend Editor, you'll see "legend type". Select "unique value" under the legend type scroll bar. Then select "section" under the "values field" scroll bar. At this point you should see the different Ecoregion Section Names of Bailey's 1996 classification. Note: you can also choose upper hierarchy levels in Bailey's ecoregion classification, e.g., Domain, Division, or Province. If you want to change the color attribute, choose a different scheme from the color scheme menu.

  10. When finished making changes in the Legend Editor, click "Apply" to apply your changes to the current view. Then close the Legend Editor window by clicking on the upper left corner (the "-" sign).

  11. You are now ready to superimpose another data layer (theme) onto Bailey's ecoregions. Repeat steps 3-7 but select Statebnd from the map coverages. Statebnd is a map of the western U.S. Note: you can always remove a coverage from view by clicking on the check box and removing the check next to the coverage. Also, any "theme" can be deleted by activating the coverage (click once on the theme legend - i.e., anywhere but the checkbox) and then selecting "delete theme" from the "edit" menu. You can tell which themes are active by looking at the gray area to the left of the view. Active themes (the check box and symbols) will appear as a thin, raised button. You can activate or deactivate multiple themes by simultaneously holding the "shift key" and clicking on the themes (anywhere but the checkbox).

  12. Because Statebnd and Bailey are both polygon coverages and occupy the same aerial extent, you cannot see the superimposition of the two coverages. However, you can change one of the polygon coverages from the fill color to an outline symbol by (1) opening the Legend Editor, (2) double-clicking on the colored symbol to open the Fill Palette window, and (3) clicking on the outline symbol in the upper left corner of the window (the square with no color or pattern). Note: the Fill Palette window is also where you can change marker colors, symbol type and size (for point data), outline color and thickness, etc.

  13. Close the Fill Palette window and click on "Apply" in the Legend Editor window.

  14. Note: you can query individual map features by (1) selecting the "i" or information button (your pointer symbol will look like a cross with a small i beneath it), (2) activating the themes you are interested in, and (3) clicking on a map feature in the view window (e.g., the Palouse Prairie region of Idaho). An "Identify Results" window will appear that describes attributes (fields) of the selected map features. Do not select "clear the window" to close it -- use the upper left "- sign." You can turn off the information option by clicking on the arrow next to the "i" button.

  15. Add Wolverine coverage to the map. Change the symbol to a "square" and choose a smaller font size (e.g., 4 or 6) - hint: you do this in the Fill Palette window. You can also choose a different color for the symbol.

IV. Saving your "project":

  1. It is a good idea to save your "map" as a project. It is not uncommon to run into segmentation errors or other errors that kick you out of the program. Consequently, save early and save often!

  2. Go to the main window (project window or "untitled1" window) and select "Save Project As" from the "File pull-down menu." Give your project a name (keep the "apr" extension). Make sure it is saving the file to your arcviewmaps directory on the h:\ or d:\ or ZIP drive.

V. How to display the feature attribute table of a coverage and query individual records in the table:

  1. Make sure the coverage you want to work with is active. For example, activate the "Wolverine" coverage.

  2. Select "table" from the "Theme" pulldown menu. Note: as you place the pointer on a tool button, a short description of the icon appears in the lower-left line of the view window.

  3. Click on any record in the attribute table, you will see the record being highlighted and its corresponding map feature highlighted on the map. For example, select the first 5 records in the Wolverine coverage by holding the "shift key" while clicking on each of the first 5 rows of the data table. Notice there is a small "window" below the control bar that indicates 5 of 164 records are selected. This is useful information, especially when you perform a query (search) for specific records in the database (see below).

  4. Return to the view window by clicking on the "Window" menu (top right - next to Help), and selecting "View1"

  5. The selected records (wolverine observations) are now yellow. You can change the "selection color" by (1) going to the "Untitled1" window (project window), (2) opening the "Projects" pull-down menu, (3) selecting "Properties, (4) clicking on "Selection Color", and (5) playing with the hue, saturation, etc. to get the color you desire. Note: this will be the selection color for all selected map features, as well as the highlight color used in the tables window.

  6. Note: You can also sort and extract simple statistics on a field while in the table window. For example, click on any field (column heading) and then click on the "sort" button (second row, adjacent to the help button). For statistics of a field (if applicable), open the "field" pull-down menu and select statistics.

VI. How to query records using logical expressions:

  1. To perform a query using logical expressions, make sure the coverage (theme) you want to work with is active. For example, activate the "Wolverine" coverage.

  2. You can perform a query either from the Tables window or the View window. In either case, make sure the coverage (theme) you want to search is active. Note: you may want to "deactivate" the other themes.

  3. Either click on the "hammer/?" button or select "Query" from the "Theme pull-down menu."

  4. In the attribute table for query building, double-click on a field, click on a logical operator (i.e., =, >, <, etc.) and then double-click on a value. For example, choose "year < 1961" -- the logical expression should appear in the lower left box. Click on "New Set." You should see the records and their corresponding map features highlighted (depending on which window you are in at the time). If you are in the Tables Window, a small "window" below the control bar displays the number records of the coverage that have been selected by the logical expression.

  5. To use a different logical expression for data query on the same coverage, you must click on the "Clear Selected Features" option in the "Theme" pull-down menu (in the View Window).

  6. Use the query option to find out how many observations where recorded in the following year categories: 1882 to 1961 = ?, 1961 to 1982 = ?, and 1983 to present = ? Are there any records that do not fit into these categories? Why?

VII. Delineating a species range (an example):

  1. Clear all selected features, and if you are in the Tables Window, move to the View Window.

  2. Make sure only "Bailey" is active (i.e., deactivate "Statebnd" and "Wolverine").

  3. Click on "Select by Theme" from the "Theme pull-down menu"

  4. Choose "Completely Contain" from the "Select features of active themes..." box.

  5. Choose "Wolverin" from the "Selected features" box.

  6. Click on "New Set" -- the selected ecoregions containing at least 1 wolverine observation will be highlighted.

  7. Notice that some highlighted ecoregions may not be valid, e.g., they cover large areas, consist of mostly atypical "habitat types" for that species, and contain only 1 or 2 observations near the edge of their borders. Use your own biological knowledge and the information in the data table (or use the "information button" to view attributes of the feature) to deselect ecoregions that are questionable. You can deselect ecoregions by (1) clicking on the "Selects features in the visible..." button (lower-left row of icons - next to magnifying glass with a + sign), (2) holding down the "shift key", and (3) clicking on the ecoregion you want to deselect. Note: make sure that only the Bailey ecoregion theme is active.

  8. To make the species range map less complicated, change "Bailey" to one color by (1) double-clicking on Bailey's symbol (bring up the Legend Editor), (2)change legend type to single symbol and select "none" from the field box, (3) changing the symbol to a light background color (e.g., faded yellow) or none (no fill).

VIII. Has the wolverine distribution changed?

  1. Double-click on the wolverine symbol (i.e., activate the Legend Editor window).

  2. Select "graduated colors" under the "legend type". Select "Year" from the fields box.

  3. Click on the "Classify" button, choose "Quantile" and set the number of classes = 5.

  4. Click on "random" or select your own colors for the 5 year categories.

  5. Change the symbol size (to a 4 or 6 pt) and, if you desire, the shape (e.g., to a square, circle, and diamond).

  6. Change the labels for year categories by (1) selecting "labels", (2) clicking on the label you want to change, (3) typing in the new label, and (4) clicking on "Apply".

  7. How else could you assess whether change has occurred? (using the data provided)

IX. Printing a black-and-white map on a laser printer:

  1. Simplify the map as much as possible, e.g., remove the outline of Bailey's ecoregions.

  2. Because you will be printing a black-and-white map on a laser printer, make sure you use black-and-white symbols (and patterns or shades for fill). Before you compose a map, click on the "View" menu and select "Properties." Click on "map unit" in the view-properties window, choose "meters" and then "OK." The map unit you have just defined is needed for plotting a bar scale on your map composition.

  3. Click on the "View" menu and select "Layout."

  4. In the Layout Window, select "Landscape".

  5. Maximize the size of the layout window and click on the "Zoom to the Page" button.

  6. Click on the "Select Graphics on the Layout" tool (the arrow button), if it is not already depressed.

  7. If you want to remove a graphic element on the layout, click on the element to make it active and then click on the "Cut Selection" button to make it disappear.

  8. If you want to move a graphic element, click on the element and drag it to where you want to have it on the layout.

  9. If you want to reduce or enlarge a graphic element, click on the element and drag its handles.

  10. While selecting graphic elements, you may need to use the "Move selected graphics in front" and "move selected graphics behind" buttons.

  11. If you want to add text to your map composition, first click on the "Create Text" tool (the "T" button) and click the mouse at the location where you want to add the text. Type the text in the "Text Properties" window and click on "OK."

  12. When you are satisfied with your map composition, click on the "File" menu, select "Print" , and then "Setup." Make sure the page orientation is set to Landscape (assuming you selected landscape in your Layout setup).

  13. Select "OK" from the print window. It may take awhile to print - be patient.

  14. You can export the map as a "Postscript" or "Windows Metafile" or "Windows Bitmap" file to use in other graphics programs (e.g., Harvard, Freelance, Powerpoint). However, map quality can be negatively affected by exporting (i.e., you get a better looking map by printing directly from ArcView). Note: postscript files (*.eps) from ArcView do not seem to work well with the graphics programs available on the UI network; however, I did not try them all. To export a map from the Layout window, select "Export" from the "File pull-down menu" and then select the drive and directory where you want to save the file.

  15. Note: There are some color printers and plotters on campus that you could try if you wanted to experiment with other output options; however, the map does not have to be printed in color.

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Revised: 25 August 2011