I was checking out our vehicle counter at the nature center the other day and I got a bit of a surprise. The counter is located in a small box with a hinged lid. When I flood the interior with light upon opening the top, I never know what I am going to see. During the warm season there is usually a small spider scurrying for dark cover or an occasional blinded yellow jacket perched on a beginner nest suspended from the top. I wait for the spider to seek refuge and flick away the ‘jacket before it recovers. The cold season lid lifting experience is far more mundane – the only thing I normally see inside the small box is the even smaller metal counter within. This time I was greeted by a pair of large mammalian eyes as the shaft of daylight cut into the interior. Those peepers belonged to a White-footed Mouse perched atop the metal lid of the counter.
I was slightly taken aback, but not enough to prevent me from carefully lowering the lid, reaching for my camera, and re-enacting the opening sequence. I had my finger on the camera shutter this time and was ready to get off a quick shot before the creature darted. It was a mouse, after all, they always dart away from light and discovery. I again lifted the lid and saw that the thing was frozen into the same exact pose as it was earlier. It had not budged an inch or moved a whisker. I quickly snapped a shot, then another, and another. He didn’t move until I lowered my hand down to nudge him off the counter.
The image that stared back at me, the one above, was the picture of intense guilt. It is the lot of mice that they always look guilty – even when they’ve not done anything to be guilty of. It is possible that all mice feel inherent guilt during every living moment of their lives. They are basically born to be eaten and there are no retirement homes for old White-footed Mice. Every breath they take, and they take a lot of them, is expected to be their last. I was not a fox, hawk, mink, or a weasel but I surely was some sort of death angel come to gather a microtine soul. This stunned creature was caught off guard and instantly resigned to meeting its maker – even if this particular grim reaper was taking his sweet time documenting the event.
It so happens that this mouse was guilty of building a nest inside the box without permission. Take a broader look (here) and you can see it in the upper right hand corner. The ball shaped nest was made of finely packed grasses, shredded leaves, and a liberal dose of winged maple seeds. Since the structure was crammed into a corner it was not in the way. This death angel, not being hungry or opposed to the idea, didn’t object. I simply nudged the maker and invited the guilt-ridden soul to flee, either to the comfort of its nest or up and out of the box. It did neither.
Although I prompted it several times, he merely scooted around and over the counter box countless times. It would not leap out or nest up. No, he wasn’t sick. His movements were spritely. But, each time he stopped, he assumed “the scared snotless position” (see here). My reassurances, rendered in an unintentional God-like voice, fell upon his very large ears but had no effect. “Kill me now,” the unblinking eyes begged, “and get it over with.” “Never mind,” impatiently boomed the big voice from above, “I’ll get the numbers and leave you alone.”
I got those numbers, closed the counter lid and then lowered the box lid. The last thing I saw was the twinkle of guilty eyes in the settling darkness next to the counter.
Mouse psychology aside, there are a few things to learn from this scenario. First of all, this creature was immediately identifiable as a White-footed Mouse by its fawn brown coat and white paws. These features are also shared by the Deer Mouse, so the only way to be sure – other than killing the beast and performing a whole host of measurements – is to look at the tail. The tail of the Deer Mouse is distinctly bi-colored and that of the White-footed Mouse is not. In other words, the Deer Mouse has a sharp delineation between the dark upper portion of the tail and the white under side. The White-foot tails, like our petrified example, gradually grade from dark into light.
On a final note, his reluctance to enter his nest probably indicates that the structure was not done. White-footed Mice first gather the material together into a ball then proceed to chew their way in to make an internal chamber. I do believe that I interrupted the nest building process in the early stages. Knowing that he couldn’t possibly think of starting over, our mouse stuck to his guns. His guilty plan, as it turned out, worked out just fine. He will have the prolonged internal comfort of his secret lair for at least another month.