Last week’s 10-inch snowfall prompted many of us outdoors with shovels and brooms to clear off walkways, decks, driveways and cars. Once those chores were done, it was time to enjoy the winter wonderland: sledding, cross-country skiing, snowshoeing and just taking in the view of the brilliant white, fluffy snow blanketing the landscape.The snowstorm also provided an opportunity to look for interesting wildlife tracks to see whom we are sharing our neighborhood with and what they are up to. Among the interesting short stories written in the snow that I examined was one discovered by Juliana Duryea, and co-authored by a red fox and either a white-footed mouse or a meadow vole. I’m going to venture a guess it was the latter.
The red fox had been hunting inside Balsam Farm’s deer enclosure; its dainty tracks led up to the wire fence to a point where it excavated a shallow hole, slipped under the fence and continued on across a gravel road.
Just before reaching a dense thicket of autumn olive shrubs, the fox came upon the bounding tracks of one of its favorite prey: the meadow vole. The bounds are relatively short, measuring two to three inches in length, and are linked by an obvious tail drag. I should note that the typical gait of our vole species is a “trot” where the left and right feet are staggered or offset, whereas the typical gait of our common mouse, the white-footed, is a two-by-two bound in which left and right feet land side by side (the meadow jumping mouse hibernates in winter). But voles will bound in deep snow.
After stepping on top of the vole tracks for a short while, the fox stopped (see bottom center of photo), its two front feet and forelegs pointing in the direction the vole had slipped out of sight and into a tunnel under the snow pack.
At this point the fox relies on its acute hearing to locate its prey. Experiments on captive red foxes have demonstrated that their hearing is most sensitive to sounds that register around 3.5 kilohertz, a frequency that corresponds to the rustling and gnawing sounds that small animals make as they move through vegetation or feed on seeds and twigs.
Pinpointing the exact location of the vole under the snow requires triangulating the sounds into each of its paired ears, and this is done by cocking its head from left to right such that each ear is at a slightly different elevation and distance relative to the vole. Research has shown that the Earth’s magnetic force also plays a crucial role, but I have not read an account that explains that well.
Owls also rely on hearing to locate prey; asymmetrical ears (one positioned higher and further forward on the head than the other) enable accurate triangulation. Using their extraordinary hearing, both owls and foxes can pinpoint the location of small prey under two feet of snow … that’s amazing!
Once it has a fix on a vole, the fox goes into a crouch and leaps up and out such that it comes straight down on the vole, pinning it with its front feet or grabbing it in its mouth. The fox’s landing, just to the left of the black glove, shows a leap of four feet.
Was the fox successful? I’m not certain, but I suspect not. There was no blood on the snow, but foxes often grab small prey without puncturing them and move to a safe spot before chomping away. What the story does reveal is that the fox leaped to the left and spun around, landing two feet away and disturbing a four-foot long section of snow. Was this an attempt to cut off the escape route of the lucky vole? I think so, and I think the vole lived to see another snowstorm.