June 2023 Natural Mystery Answered
Last month’s Natural Mystery of tracks in mud asked both who and what gait? While the species that left the tracks is common, the track pattern is not typical which may have made the prints difficult to identify. We did not receive any correct answers to this mystery. My guess is that you will recognize both the tracks and the track pattern once they are pointed out.
This is the walking trail of an Eastern Gray Squirrel (Sciurus carolinensis)
Gray squirrels most often move on the ground by bounding, but they also walk, especially while foraging. This is usually for short distances—sometimes no more than a couple of steps before it is punctuated by bounds—but occasionally they leave longer walking trails. Just as when they bound, the hind feet track wider than the fronts. This results in an indirect register with the hind tracks more-or-less beside the front tracks. This indirect register means that the hind track often partially covers the front, making it a bit more challenging for us to see the key features we typically use to identify squirrel tracks.
In addition to this, tree squirrels are less likely to register their heels when they walk than when they bound. In this series, the hind feet consistently register digitigrade. We see no heel registration in the first front track in the series, and a partial heel in the last front track in the series. Only in the left front, just above the ruler, can we clearly see the two heel pads typical of bounding squirrel tracks.
Despite this, we can still see many key squirrel features. We can see the long, fingery toes and clear claw marks typical of our tree squirrels. We can make out five toes on each hind foot with the tips of the three middle toes arranged in a straight line. Some of the front tracks only show three clear toes, but the left front shows four and the arrangement is typical for a tree squirrel—with toe 4 a little longer than toe 3. The three fused palm pads on the front track are arranged a pyramid shape. The pads forming the hind palms are arranged in an arc.
As always, thanks to everyone who sent in an answer to this mystery.