Post by Jen Berlinghof
As the thermometer dipped to -8 degrees Fahrenheit this week, one thing was clear: the snow and cold are entrenched for a while longer. So are the stories of the animals, as told by the tracks etched in the frozen landscapes that sweep across the Lake County Forest Preserves. We may not see the animals themselves. However, each track, pile of scat, bit of hair clinging to a branch, hole in the snow and chewed acorn is an element of the tale from their winter excursions.
How do we decipher these stories? When trying to identify which animal made a particular track, it is important to look not only at the individual track but the overall pattern. Also, scan the surrounding habitat for clues.
Let’s see if you can figure out what happened in each of these nature vignettes:
In the picture above, the tracks begin at the base of a tree and consist of two small impressions, side by side, with a line imprinted in between. The individual tracks are tiny compared to the tree and are difficult to see, but notice the other clues: the size, the hopping pattern (hind legs land ahead of the front legs), the tail dragging in the snow. Add it all together, and these tracks are unmistakably those of a mouse. The white-footed mouse (Peromyscus leucopus) is a good climber known to repair old bird nests in woodlands, creating a cozy winter home. Perhaps this nocturnal rodent scurried down from its arboreal home for a midnight snack.
The photo above illustrates an ambush from above. Voles make tunnels beneath the snow in open areas. They have a similar gallop pattern to mice, but since voles have a short tail there is no impression of it in the snow. A meadow vole (Microtus pennsylvanicus), seems to have hopped out of its subnivean tunnel near a hungry red-tailed hawk (Buteo jamaicensis). Perhaps this hawk was scanning the open fields from the top of nearby tree when it spotted movement a half-mile away and then attacked in its signature style: a controlled dive with legs outstretched.
Was this a human doing handstands and broke a small tree? Likely not. A beaver’s webbed hind feet and leave a very recognizable track as it lumbers back and forth near water, creating a distinctive waddling pattern. American beavers (Castor canadensis) spend most of the winter holed up in a lodge, feasting on cached food and living off fat stored in their paddle-shaped tails and elsewhere on their bodies. The lodges stay relatively warm in the winter. In one Canadian study scientists found that when outdoor temperatures plummeted to -30 degrees Fahrenheit, the average minimum temperature inside the lodge was 34 degrees Fahrenheit. Perhaps a late-winter thaw (that we will hopefully have soon) tempted this beaver to clamber out of its lodge in search of fresh food.
Coyote (Canis latrans) often hunt open areas in pairs or small groups, using trails of smaller animals to conserve energy and avoid deep, heavy snow. Their prints have four toe impressions with nail marks punctuating the top of each toe. Coyotes are considered “perfect steppers.” The hind foot registers on the track made by the front foot, creating a straight line of single prints. Sometimes the hind foot lands behind or to the side of the front track, varying in the pattern. Perhaps this is a small group of coyotes hunting together or multiple coyotes using the same path at different times to a den?
The mink (Mustela vison) is a long, slender weasel that spends the majority of its life within 100 feet of water. In the winter, this nocturnal carnivore hunts through holes in the ice to capture slow-moving prey, such as fish and crayfish. It bounds through the snow, leaving five-toed tracks in evenly spaced bunches or pairs. Sometimes minks push forward, creating a slide and then diving under snow to dig into the mud in search of hibernating critters. Perhaps it found a tasty morsel under this snow drift and may have scared a vole back into its tunnel in the process.
These are just a few of the snowy stories that Lake County Forest Preserve Educators and volunteers have uncovered. As the sun sets, take advantage of extended hours offered along solar-lit trails at Old School and Lakewood Forest Preserves.
Here’s a starter guide for your adventures: LCFPD Track Identification and Walking Gaits.