by Carl Strang
Snow that fell around the turn of the year has provided good tracking opportunities at St. James Farm Forest Preserve. As I walk the new survey routes I established in December, I am beginning to assemble a sense of the general mammal presence and activities on the preserve. For instance, I found that cottontail rabbits are much more abundant and widely distributed than my earlier first impression indicated. The species list also is growing. For example, I ran across some mink tracks on New Year’s Day.
At first I was excited, because they seemed smaller and less round than mink tracks usually are, but they proved to be those of a mink rather than the locally rarer long-tailed weasel.
With minimal wandering the mink, possibly a female by the small size, came straight out of the forest and into the newly reconfigured stream.
A new species record is welcome, but even more welcome was a bit of a mystery that came the next day.
Skunk tracks in the snow!
This was surprising because, in my previous experience, skunks didn’t emerge from their dens in early January unless the temperature overnight was at least 30-40F. It had been in the mid-teens. As I followed my route I was able to trace the skunk’s course, roughly a straight line to the preserve’s boundary against a residential neighborhood. Later I backtracked this individual to a contorted tangle of footprints in a difficult to negotiate (for me) spot in the woods just north of Butterfield Road. I wasn’t able to cut this skunk’s entry into that area, so perhaps its den is there.
That wasn’t the end of it, though, as I soon crossed a second skunk’s trail. This was a different individual, larger and with a significantly wider straddle. Its feet were dragging significantly. Sorry, it didn’t occur to me at the time to photograph those tracks. I encountered them near where skunk #2 was exiting the preserve, again into the neighborhood to the east. As I continued my walk I was able to backtrack this second animal, occasionally cutting his trail and occasionally following it.
Here is the habitat map of northern St. James Farm. M shows where the mink was, S1 is the narrow-straddle skunk, and S2 is the wider-straddle individual. Solid lines show where I followed the tracks, dashed lines indicate areas between places where I cut the animals’ trails.
Ultimately I traced a good mile that skunk #2 had hiked. No wonder its feet were dragging at the end, and the foot drag gradually vanished as I backtracked it. It had crossed the parking lot after visits to the ranger residence and the round office building. Before that it had crossed the trail of skunk #1 (close enough in time that my skills are inadequate to say which individual passed that way first) after taking the Prairie Path tunnel under Butterfield Road. It had emerged from the woods south of Butterfield, still on the preserve, but a locked gate blocked my further progress.
This is the kind of traveling I expect in February, when the striped skunk mating season arrives. Then, they are much more likely to come out on the colder nights. As this winter progresses I look forward to learning whether St. James Farm’s skunks in the winter of 2015-16 habitually emerge to wander more often and in colder weather than skunks in other years in other places.