Kernel Home Range Estimation for ArcGIS, using VBA - Fish and ...

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document or map template may be saved with other names. Data should be loaded into the document in the form of a shapefile. It is recommended that the data are projected in UTM meters (ABODE has not been tested with other projections systems yet). 8.2. Using ABODE for home range analysis In order to facilitate the automation of tedious home range analyses, ABODE provides options for subsetting datasets. This is equivalent to running batch mode. This allows users to load their data as a single shapefile into ArcMAP. As an example, one shapefile may have the location data (x and y coordinates), day, month, year, and ID for all the animals in a population. When subsetting, the user chooses the field on which to subset (i.e. the ID field), and ABODE will then run the anaylsis for the data that have the same value in that field, before starting new analysis for the next value. Thus, if a dataset has 5 individuals, with IDs “1”, “2”, “3”, “4” and “5”, and if the field “ID” is chosen for subsetting, ABODE will run the analysis first for the records for individual “1” then for individual “2” etc, and then provide a single table as output containing the results from the 5 analyses. ABODE can only handle subsetting at one level, but if separate analyses are desired for multiple fields, then the fields in the dataset should be manipulated in either ArcMAP in the attribute table or in a software package such as MS Excel, MS Access or SAS, before being imported back into ArcMAP. In this manner, a yearly analysis by individual is possible by generated a field (i.e. “IDyear”) in which the ID and year are concatenated (individual “1” in year 83 would be 183, and year 84 would be 184 etc). Since some of the options in ABODE are date sensitive (they require day, month and year fields) it is suggested that a date field (if available) be converted to separate fields for day, month and year. This can be done in MS Excel using the functions ‘=day()’, ‘=month()’ and ‘=year()’. 8.2.1. The Visual Basic form and error trapping ABODE was designed to be a relatively simple program with open code. The benefit of this feature is customization. The field of home range analysis is progressing fairly rapidly. No estimation techniques are or should be taken as irrefutable truths. Thus, it is anticipated that the technology and theory behind home range estimation will change. In addition to this, no technique will fit all data. Instead of ‘massaging’ data to fit a technique, techniques should be developed and changed such that we are faithful to our data and their capabilities. Written in Visual Basic for Applications and ArcObjects, you as a user have the ability to change the code. The user interface is a simple form in which you enter or select parameters to be used in the analysis. 46
ABODE has been tested, but as with most software, it has not been tested enough. The form is designed in such a way that it traps potential errors before the code runs. This prevents the user having to debug code line by line – a tedious and difficult procedure. The drawback is that the form may be a source of frustration to many users who are trying to customize their analysis. In most cases the form will not allow procedures that may cause the program to crash. This often occurs when the user has not chosen a required input. When the form fails to catch these potential errors however, and error message will occur, that asks the user if they wish to ‘debug’ (Figure 8.2.1.1.), if the “Allow Debug” checkbox is checked. Figure 8.2.1.1. The user may choose to debug (this is not recommended) or may choose ‘end’ (recommended), and determine based on the attempted inputs why the procedure was not allowed. Choosing to debug will open the Visual Basic Editor. If the user wishes to exit at this stage they may close the editor. At this point they will be prompted with stopping the debugger (Figure 8.2.1.2.). Choosing “Cancel” will return the user to the visual Basic Editor. Choosing “OK” will close the editor and return the user to ArcMap, closing the failed ABODE procedure. If you forgot to check the “ESRI Spatial Analyst Extension Object Library” and “ESRI Spatial Analyst Shared Object Library” (Figure 8.1.2.12.), you will get an error when you first run a kernel analysis (Figure 8.2.1.3.). In this situation, click “OK”. Go through the steps outlined above (Section 8.1.2.) for setting the required references. Then close the Visual Basic Editor. Go to the folder you chose for saving 47
Page 1 and 2: ABODE Kernel Home Range Estimation
Page 3 and 4: 1. Preface Home range analysis is a
Page 5 and 6: They are both extensions that can b
Page 7 and 8: 3.2. Problems with polygons The def
Page 9 and 10: a b c d Figure 3.3.2. As explorator
Page 11 and 12: −1 ⎧3π K 2 ( x) = ⎨ ⎩0 ( 1
Page 13 and 14: a b c Figure 4.1.4. Assigning pixel
Page 15 and 16: example at only 1750m from the poin
Page 17 and 18: σBxPB P and P are Silverman (1986)
Page 19 and 20: follow P is a b Figure 4.3.2.2. Gen
Page 21 and 22: 4.4. Discretization and the effect
Page 23 and 24: a b c Figure 4.4.5. Visualization o
Page 25 and 26: Figure 4.4.8. Degradation of h usin
Page 27 and 28: a Figure 4.5.1.1. Unit Variance Sta
Page 29 and 30: 4.5.3. Covariance Bias Seaman and P
Page 31 and 32: locations for LSCV. They showed tha
Page 33 and 34: 6. Core Home Ranges 6.1. Does a cor
Page 35 and 36: a Figure 6.2.2. Methodology for gen
Page 37 and 38: ehavior of our study species will g
Page 39 and 40: less than two weeks (14 days) then
Page 41 and 42: in the drop-down menu reads “Unti
Page 43 and 44: The active window is the “ThisDoc
Page 45: One more step is required to start
Page 49 and 50: Figure 8.2.2.1. Figure 8.2.2.2. The
Page 51 and 52: Figure 8.2.2.3. This analysis runs
Page 53 and 54: 8.2.3. Kernel Density Estimation Th
Page 55 and 56: contains the value. For all of the
Page 57 and 58: data will produce a fine resolution
Page 59 and 60: “Kernel” button should be used.
Page 61 and 62: Jenrich, R.I., and Turner, F.B. 196

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