Mouse Snacks

The light dusting of snow we received the other night was the perfect substrate for mouse tracks.  The morning light revealed a mouse freeway leading from the stack of flower pots to the mess of seed under the bird feeder. Their tiny tracks look like a smaller version of red squirrel tracks.  Mice and squirrels both hop by placing their smaller font feet down first, then bringing their larger hind feet around the sides.  As the hind feet hit the ground in front of the front feet, they give a mighty push for the next hop.  Rabbits also move in a similar way. 
 

You can decipher an interesting bit about the ecology of a hopping track-maker by the placement of their front feet. Arboreal animals, those who spend a lot of time in trees, will place their front feet right next to each other, perpendicular to their line of travel.  Squirrels do this, and a little surprisingly, deer mice are excellent tree climbers and therefore are sometimes paired-front-foot hoppers. Rabbits and hares, who are not often observed in trees, place their front feet with one ahead of the other, at an angle to the direction of travel.  Can you decipher all the tracks in your yard?

The appearance of deer mice – light brown back, white belly, and big ears – is reminiscent of a white-tailed deer.  Mice have much longer tails, though, which aids in their tree climbing.  Deer mice have a closely-related and almost indistinguishable cousin, the white-footed mouse.  To tell them apart, experts look at a difference in the amylase molecules of their saliva.  You might remember amylase from biology class when you chewed on crackers until they tasted sweet.  Amylase is an enzyme that breaks carbohydrates into simple sugars.

 

Food is especially important during the winter for these tiny active critters.  Mice will cache food (including weed seeds, birdseed, berries, and my cookie crumbs) in the fall, and throughout the winter.  Several times I have curiously brushed the snow off of an abandoned bird nest and discovered a tidy little mouse pantry.  Earlier this winter I accidentally left a Mason jar with birdseed in it on the patio.  I found it a few days later, with the contents spilled onto the snowy path.  Squirrel tracks, mouse tracks and tunnels surround the windfall as they busily hoarded the treat.

Eating plenty allows the mice to run their metabolism on full speed to keep warm.  In the winter they add new red blood cells with more hemoglobin to fuel their roaring metabolism. After creating all that heat, mice do their best to conserve it through the day when they are not active.  Body temperatures may be allowed to drop as they snuggle in next to other mice in a cozy woodpecker hole, thatched-grass nest, bluebird box, or the warm micro-climates of our homes.

Peering out of my home early one morning, I witnessed a bit of natural drama.  My local gray fox stood on the path by the corner, in person, not just in tracks! He was just ten feet away, standing over the remnants of spilled birdseed.  In the shadowy pre-dawn, I watched as he nuzzled the snow and came up with a limp mouse hanging from his jaws.  With a flick of his head, the mouse disappeared in one gulp. The fox trotted nonchalantly down the path leaving delicate tracks in the fresh dusting of snow.

In December, the fox tracks whispered “Listen…it is music to run over the hills” Now he adds: “Death itself is a music…It is flesh and bones changing shape and with good cause. Mercy is a little child beside such an invention.” (Straight Talk from Fox in Red Bird by Mary Oliver). 

 

For over 44 years, the Museum has served as a guide and mentor to generations of visitors and residents interested in learning to better appreciate and care for the extraordinary natural resources of the region. The Museum invites you to visit its facility in Cable at 13470 County Highway M. The new exhibit, The Joy of Birds: Feathers in Focus opened in May, 2011. Find us on the web at www.cablemuseum.org to learn more about our exhibits and programs. Also discover us on Facebook, or at our blogspot, http://cablemuseumnaturalconnections.blogspot.com/.