As I've said before, I was very pleased to see the amount of Franklin's activity on the sight. In total, I used 12 traps on the sight. 5 were placed along the grassy strip to the right of the lane near burrow entrances and the other seven were placed in the prairie restoration area. Most of the prairie traps were located around the largest clump of trees where I found some aditional burrows. A few of the traps were moved around throughout the week if an individual was repeatedly captured. On the first day (5/29) the traps were left open from roughly 8:00 am until 4:00 pm and checked twice throughout the day. Five individuals were captured, 4 females and 1 male (one cottontail rabbit was also trapped on this day). On 5/30 the traps were opened at 8:00 am again and were only left open until noon. 5 new males were captured on the second day. On the last day of trapping, 6/1, the traps were only left open for the morning again and 1 new female was caught. So the total number of captured squirrels was 11. All of these were adults and all of the females showed signs of lactation indicating active reproduction. A patch of fur was clipped off of the rump to indicate recaptures.
Throughout the rest of the summer I only found one other sight that had Franklin's. It was along a railroad track in the northeast corner of Vermilion Co. In three days of trapping there, I caught 23 individuals. Out of these 23, 5 were adults and the rest were recently emerged juveniles. Because the young in your population weren't active yet, I can't accurately compare the size of these two populations with my current data.
I would like to thank you again for your interest and cooperation in regards to my project. It does seem like the faunal make-up of your prairie is not the norm for Illinois. I'm sure that there are many more populations of Franklin's ground squirrels in the state but they definitely don't seem to be as common as they used to be. The remaining populations are also becoming pretty sparce and isolated along with their habitat which isn't helping matters much. I suspect that most of these remaining populations occur along railroad rights-of-way, the narrow "strip" structure of which may be having serious impacts on population dynamics, especially on the dispersal of juveniles and overall survivorship. This is why the maintenance of areas with a more natural structure, such as your prairie, is extremely important. Do you know if thirteen-lined ground squirrels occur on the sight? I didn't see or capture any when I was there, and I also didn't see any at my other capture sight, so I've been wondering about possible competition issues between Franklin's and Thirteen-lines.
Over the next few weeks I will be meeting with my advisory committee
to discuss the direction that my project will be going in the next year.
I would like to explore some of the above mentioned population dynamics
questions. If you are agreable, I would really like to work with
the Franklin's population on your property again next summer. Right
now I have no specifics in mind, but I would obviously keep you in the
loop and keep any concerns that you would have first and foremost in my
Please let me know if this would be possible. Thanks again and I look forward to hearing from you soon.
Graduate Student, University of Illinois
Dept. of Natural Resources and