Creating a Roadkill Observation Density (aka Hotspot) Map


On the IFWIS Roadkill Observation webpage (, click Export Roadkill Data near the lower-right corner of the page.  This leads you to a records filter that allows you to query by species, date observed, highway, and milepost.  Once you have applied the filter(s), the data can be downloaded as an Excel .csv file, which can then be saved as an .xlsx file.  In ArcCatalog, create a point shapefile or geodatabase feature class (right-click the .xlsx file and click ‘Create Feature Class’). In ArcMap, use the Spatial Analyst toolbox --- Density toolset --- Kernal Density or Point Density tools to create roadkill density rasters. Depending on what the output raster is being used for (as a visualization tool, for strict data analysis, etc.) one method may be preferred over the other (read more about the differences).  You can customize the output raster cell size and search radius. ArcMap provides a Spatial Statistics toolbox for Cluster and Outlier Analysis and Hot Spot Analysis that identifies statistically significant hot spots, cold spots, and spatial outliers using Anselin’s Local Moran’s I or Getis-Ord Gi* statistics.


BONUS:  Idaho Department of Transportation Average Annual Daily Traffic (AADT) data is available on the INSIDE Idaho website.  The Roadkill and AADT data can be “combined” (think raster math) to create a categorical map that simultaneously reflects roadkill and traffic density. 



Observations and Roadkill Posters

For anyone interested in helping promote the use of these systems, here are graphics we've started with for Observations and Roadkill online reporting forms.

Observations Roadkill


We'd appreciate it if you are using these as web images, that they would link directly to either Observations ( or Roadkill (


Displaying Recent Roadkill on your Webpage

You can use the Roadkills API to display the most recently reported roadkill on your webpage.

Passionate about Mule Deer perchance?  In a couple quick steps you can add a real-time list of the Recent Mule Deer Roadkills using the magic of JQuery and the Roadkills API.  First, a demo, then the code.


Recent Mule Deer Roadkill

    Loading Roadkill...

The Code

<ul id="roadkillfeed">Loading Roadkill...</ul><script type="text/javascript" src="{YOUR GOOGLE API KEY}">
    <script type="text/javascript" src=""></script><script type="text/javascript">
        google.load("feeds", "1");

        google.setOnLoadCallback(function () {

        function initializefeeds() {
            var feed = new google.feeds.Feed("" + parseInt(Math.random() * 99999999, 10));
            feed.load(function (result) {
                if (!result.error) {

                    var content = document.getElementById('roadkillfeed');
                    var html = '';

                    for (var i = 0; i < result.feed.entries.length; i++) {
                        var entry = result.feed.entries[i];

                        html += '<li><a href="' + + '">' + entry.title + '</a></li>';

                    content.innerHTML = html;

Substitute your Google API Key and your customized URL and you're live!  Well, not the roadkill, but the page is displaying live data as it arrives!