Of Mouse and Man

We live in an old farmhouse where resident mice are a fact of life.  Generally, they are deer mice, a species typically associated with woodlands and scrublands. As mice go, they are good looking, with sleek brown and white fur and black, beady eyes. They are at home in our home, having ready access through the crumbling mortar of a field stone foundation.  They run jubilantly to the interior, seeking out the deepest recesses, feasting and basking in relative warmth and comfort.

They are an invaluable part of the web of life, providing a necessary and abundant food source for a host of predators from snakes to raptors to coyotes.  Even within the confines of our house the mice are certain to occasionally fall prey to the fox snakes inhabiting our crawl space.  Sometimes the mice push me beyond my tolerance so I join the ranks of predator and declare war, engaging my weapon of choice: the Victor mousetrap. Open seasons vary in length and frequency, depending on the relative abundance and destructiveness of mice, and the law of diminishing returns applies, so in every proclaimed season I remain engaged until efforts no longer yield acceptable results. 

And so it was a couple weeks ago when I opened a pantry door in the basement and found a shelf fairly littered with mouse turds and the shredded package remains of more than a pound of pasta.  I deployed a line of Victors and over a period of several days the perpetrators, or at least the bulk of them, were brought to justice. The pasta was replaced and peace restored.

Then more recently I opened a desk drawer and found a quantity of uneaten niger seed piled on a notepad.  I set a Victor, baited with a dab of peanut butter and topped with niger.  It went untouched.  A couple days later a similar pile appeared on my desktop so the trap was relocated, but again ignored.  It occurred to me I was trying to attract a mouse at a cache site, a place where food was being stored for later consumption, and this mouse was not in feeding mode.   This was a new experience which, to date, has not been resolved, and the mouse remains at large.  

On our back porch is a granary of sorts containing a consistent inventory of black oil sunflower, niger, and cracked corn used to replenish bird feeders.  A virtual mouse smorgasbord. Often, when my mouse tolerance is tripped, it is there I lay the Victors, usually with favorable results.  

During this glorious and persistent winter we are cross country skiing on a daily basis.  I keep my ski boots on a rug in the office, a full 30 feet from the granary. Overnight, one of my boots was filled with a strong half cup of sunflower seed.

A study found that a deer mouse can carry about 10 grains of wheat at a time in its cheek pouches.  I would estimate a single black oil sunflower seed to be two to three times the size of a grain of wheat, so it follows that a mouse might carry four or five sunflower seeds at a time.  Through a little investigation (the type reserved for mouse researchers and those delightfully retired with abundant time on their hands) I learned there are approximately 600 sunflower seeds in a half cup, so the mouse in question could have made 150 round trips from the granary to the boot.  At 60 feet per completed trip, the total distance covered would exceed 1.7 miles.  If we give the mouse three seconds to load up, plus ten seconds round trip travel time, the half cup cache would be filled in a little over half an hour.  All of this, while impressive and interesting, does nothing to address the issue of sunflower seeds in my boot and a mouse still on the run. 

I am reminded of a time back in the day when I was a working biologist and had a client who was having a love affair with bluebirds. He had installed several nest boxes, one of which had been claimed by a house sparrow.  I had recently written an article about the aggressive nature of this exotic sparrow and how it often outcompeted bluebirds for nest sites.  My client, a retired military man with a square jaw and the demeanor of a drill sergeant, had embraced a singleness of purpose and was hell bent on terminating the sparrow.  When I met him he was dressed in full camo which appeared freshly ironed, and was describing a blind he’d built close to the birdhouse occupied by the enemy.  On multiple mornings he had taken up position in the predawn, waited patiently, but failed to meet the objective.  He relayed his experience speaking through clenched teeth.  I am unsure of the final outcome.

So it is with us and the wild species with whom we share the planet.  We establish tolerances, define limits on acceptable behaviors, implement control measures when necessary.  And sometimes we’re bamboozled, made fools by animals we consider far less intelligent.  Bravo to them.