Corridor Design Blog

News and views on wildlife corridors, linkages, and connectivity

Posted by
Dan Majka
on Feb 23 2010

New version of corridor evaluation tools now available

We have a new revision of the Corridor Evaluation tools available on the downloads page. Improvements include:

  • an improved histogram tool which allows you to visually compare distributions of habitat data within corridor polygons
  • a new Crosstab tool to let you compare alternative corridor options based on two variables.
  • a tool which allows you to combine multiple species corridors or patch layers to see how many species are represented at any point on the landscape.
  • a Suggestions button on the About dialog which gives you an easy way to suggest new tools to us.

Compatibility problems with ArcGIS 10

The next version of ArcGIS has recently been renamed from ArcGIS 9.4 to ArcGIS 10. One of the reasons ESRI decided to change this from a minor to a major new release is that they are completely changing the way ArcGIS recognizes custom extensions.  Because of this, the Corridor Evaluation tools will likely be completely disabled. The Corridor Evaluation tools are written in Visual Basic 6, and ESRI has changed the way that ArcGIS recognizes custom extensions in such a way that there appears to be no simple way to get ArcGIS to see that the tools are even there.

Jeff Jenness is a Beta tester for ArcGIS 10 and is looking for a way to get the tools to work. So far, ESRI is recommending to rewrite them in VB.NET, and this solution would certainly work. Unfortunately the tools are fairly complex and substantial (over 62,000 lines of code at latest count), and since we don’t have funding for this, we would have rewrite the tools in our free time. Therefore it probably won’t happen anytime soon.

We have not heard of any major changes to the Python environment, but will let you know if the ArcToolbox tools for designing corridors will be affected as soon as we find out.

Installing ArcGIS 9.3.1 Alongside ArcGIS 10

Previously, ESRI was going to change the installation and registration of ArcGIS in such a way that you could install both ArcGIS 9.3.1 and ArcGIS 9.4 (now ArcGIS 10) on the same system. This was one of the major announcements at last year’s ESRI User’s Conference, and it might be a reasonable solution to allow you to continue using the Corridor Evaluation tools. Unfortunately ESRI has backed off from this promise, explaining that it turned out to be much more complicated than they had anticipated. At this point, it sounds like they do not mind if you have both versions installed, but you will need to install one of them in a virtual environment such as the Windows XP Virtual Machine available in Windows 7 Professional and Ultimate.