12: Lab Telemetry Week 13: Telemetry Presented by: Jaime Collazo and Ed Laurent Friday, April 13, 2007 Objectives: Calculate minimum convex polygons Calculate home range kernels Extract land cover use and availability values Interpret use vs. availability figures Outline: 1. 2. 3. 4. Use HawthsTools to calculate MCPs and Kernels Extract land cover values at points and within mcps, kernels and the study region Summarize land cover use vs. availability as percentages Compare use vs. availability graphically and statistically
Required Readings: Blouin-Demers, G. and P. J. Weatherhead. 2001. Habitat use by black snakes (Elaphe obsolete obsolete) in fragmented forests. Ecology 82(10):2882-2896
Lab 12: Telemetry Week 13: Telemetry Presented by: Jaime Collazo and Ed Laurent Friday, April 13, 2007 Exercise: Data: 1. Snake_locations.shp GPS locations of marked snakes found using radio telemetry. Contact David Woodward ([e-mail]) for more information. 2. landcover grid of land cover classes 3. study_area.shp polygon identifying the study area 4. LC_Names.dbf text descriptions of land cover codes Add the above data to a new project. Join LC_Names.dbf MAPCODE field to landcover VALUE field. Import the landcover.lyr symbology as unique values for the joined MAPUNITNAME field of the landcover grid. Use HawthsTools to generate minimum convex polygons for each snake: HawthsTools -> Animal Movements -> Create Minimum Convex Polygons. Point locations layer: snake_locations Check "Create a different MCP for each unique value in this field": SNAKE_ID Output: c:\workspace\lab12\mcp Use HawthsTools to generate 50% and 95% home range kernels for each snake: HawthsTools -> Kernel Tools -> Batch Fixed Kernel Density Estimator Point locations layer: snake_locations Unique ID field (integer): SNAKE_INT Smoothing factor (h): 250 Select "Minimize the extent..." Output Raster cell size: 30 Check percent volume contours: 95, 50 Output folder: Click the folder button -> add a new folder -> rename folder "kernels" -> select this new folder Add all the new kernels to the view Use HawthsTools to generate polygons for the kernels: HawthsTools -> Kernel Tools -> Percent Volume Contours Raster layers: select all the "kde" kernel grids Isopleths (percent): 95, 50 Output: Check Polygons only, uncheck other options Output folder: Click the folder button -> add a new folder -> rename folder "kernelpolys" -> select this new folder Add all the new kernel polygons to the view Remove all the kernel grids from the view. You will not use them again.
Add the SNAKE_INT number to each set of polygons: HawthsTools does not provide a way to distinguish the source of each kernel estimate in the table, it only does it in the file name.. You will therefore change the ID number to match the SNAKE_INT number for the snake locations that were used to generate the kernels. Starting with kde_1_poly -> open the attribute table -> right click on the ID field -> Calculate Values -> Id = 1. Repeat for each polygon, changing the ID value (0) to the SNAKE_INT used to generate the original kernels (e.g., kde_2_poly -> Id = 2, kde_3_poly -> Id = 3, ...) Use the Append (Data Management) Tool to merge the kernels into a single shapefile Data Management Tools -> General -> Append Input Features: Add kernel "kde" polygons 1-9 Output features: The last kernel, should be "kde_10_poly" Schema Type: No Test This operation results in the kde_10_poly file now containing the kernels for all the snakes, with the ID field indicating which SNAKE_INT was used to generate the kernel. Remove all "kde" polygons except kde_10_poly Your project should now look something like this:
You will now summarize land cover for each snake location, for each mcp, for each kernel and for the study area. To extract land cover values at each snake location: HawthsTools -> Analysis Tools -> Intersect Point Tool Point file to intersect: snake_locations Select layers to intersect with: RASTER -> Check landcover The result is a new field in the snake_locations attribute table with the land cover value of the grid cell at each point. To summarize land cover within kernels mcps, and study region: HawthsTools -> Raster Tools -> Thematic Raster Summary Polygon layer: mcp Thematic raster: landcover Output table (dbf): mcp_land.dbf Repeat for kde_10_poly (output: kernel_land.dbf), and study_area (output: study_land.dbf) Add the three new output tables to the project. The mcp_lanb and kernel_land tables will need to be joined to their source attribute tables. To join the output tables to their source file's attribute table, right click on the shapefile -> Joins and Relates -> Join -> Join attributes from a table mcp 1. Field that the join is based on: FID (refers to feature ID) 2. Choose the table...: mcp_land 3. Choose the field...: PolyFID kde_10_poly 1. Field that the join is based on: FID 2. Choose the table...: kernel_land 3. Choose the field...: PolyFID Export to your lab folder the attribute tables of the following layers using the following names: To export attribute tables, right click on the layer -> Open Attribute Table -> click the Options button (on bottom of table) -> Export. Do not add the tables to the map. snake_locations = loc_cover mcp = mcp_cover kde_10_poly = kernel_cover Open Excel and open the following tables. You will need to change the "Files of type" to dBase Files (*.dbf): 1) study_land.dbf, 2) loc_cover.dbf, 3) mcp_cover.dbf, and 4) kernel_cover.dbf Open the SnakeSummaries.xls in your lab folder. Copy the data from each table into the sheet with the same name as the source table (e.g., loc_cover) and save the workbook. The easiest way to copy and paste the values is to select the top left gray cell in a table, hold Ctrl + c to copy, select the top left corner on a new sheet in your workbook, Click + v to paste.
On the study_cover page, copy the cells (not columns or rows) containing data. In the AA1 cell, right click and select paste special. Check the `Transpose' box and click ok. Delete all columns to the left of AA. Delete row 1. Rename cells A1 "LandCover" and B1 "Count" On the mcp_cover page, select the cells containing data. In the AC1 cell, right click and select paste special. Check the `Transpose' box and click ok. Delete all columns to the left of AC. Delete rows 1 and 3-7. This leaves you with the snake ID and the count of pixels within each cover type. Rename cell A1 "LandCover" On the loc_cover page, create a pivot table to summarize land cover for each snake location: Select the columns containing data. Click Data -> PivotTable and PivotChart Report -> Next -> Next -> Layout. Drag ...