I figured out a solution to my circle problem in case you're 
interested. The result is similar to that of running s.menu, option 
7 (convert site to raster - freq of occurrence) except the sites turn 
into circles of a defined radius and the values in the raster are the 
frequency of circles that circumscribe each grid square. 
Since I had to repeat the process on 244 animal-season files each 
containing up to 50 sites, I wrote a really ugly shell script to do 
the work.  Let me know if you're interested in seeing it.


