• BOOKS ABOUT WILDLIFE AND HEALTH

  • New Children’s book reader grades 3rd thru adult

    Koda watches 06 swim the Lamar River

  • Available from Amazon paperback or Kindle

  • Updated w/double blind study results. Ebook or paperback

  • New updated edition available NOW!

  • Recent Posts

  • Tracking Footprints

  • Archives

  • Top Posts

  • Pages

Tracking small mammals

With warm temperatures and little snow in my mountain lion tracking areas, I’ve turned to tracking small mammals above my house.  I’m not sure if I am just becoming aware of what these tracks look like, or if I am actually noticing an explosion of long-tailed weasels this year.

During last summer, we had a lot of reports in the neighborhood of weasels.  One neighbor told me her indoor cat killed a baby weasel and left it in the living room.  Obviously, some weasel had gotten into her house and had a litter.  Because weasels kill a tremendous amount of mice, she wasn’t too happy with her cat.  I personally watched a weasel take three baby bluebirds from their nest that were about to fledge.   I attribute all these sighting to an explosion of Unita ground squirrels this summer.

The weasel family has a distinct gait, especially in snow, called a 2×2.

you can see the 2x2 gait where the back feet land in the front feet tracks.

you can see the 2×2 gait where the back feet land in the front feet tracks.

These are really clear weasel tracks on the porch

These are really clear weasel tracks on the porch.  My shoe for size.

The only way I could figure out what kind of weasel I was seeing was to take measurements of the track width.  After taking lots of measurements, I found I’m seeing long-tailed weasels, not ermines.  From my observations, it appears that weasels hardly ever backtrack, unlike squirrels who make a deep trails back and forth between their caches and trees.  They wander from one rock or juniper to the next looking for mice and voles.  The reason you rarely see backtracking is because, unlike squirrels, they don’t have permanent dens.  Instead they go out looking for prey, make a kill, then take over their prey’s nests.  They might use these nests for a few days only.

Vole tracks on snow

Vole tracks on snow close up

Vole bound.  You can see it's tail drag

Vole bound. You can see it’s tail drag.  My shoe is for size.

 

Mouse tracks in snow

Mouse tracks in snow

I’ve found these weasel tracks in fairly predictable areas–forested areas encircling small to medium sized meadows.  This would make sense considering their prey consists mainly of voles and mice.

I followed a weasel track into the trees and came across Marten tracks.  Martens, like weasels, are mustelids and have that characteristic 2×2 in snow except much bigger.  Where weasels have a trail width of 1″-3″ depending upon which weasel, martens have a trail width of 2 3/4″ to 4 1/2″ and a much bigger foot.  Once you start to recognize these tracks, they will be easy to distinguish from rodents and from each other.

Scale shows width of track

Scale shows width of track

Ruler shows trail width

Ruler shows trail width

The Martens, unlike the weasels, like to travel in heavy timber for protection.  They also eat voles, but take squirrels, carrion, berries,fruit, chipmunks and birds.  Martens climb trees whereas weasels rarely do.  They prefer old growth forests.  James Lowery says that ‘logging that removes old growth trees and forest management practices that result in islands of forest separated by open space do not provide good habitat for marten and, some would say, destroy the health of the forest as well.”    Lowery’s comments makes me wonder about the logging that is going on this winter in the Sunlight area.

I walked up Little Sunlight Campground the other day which has been extensively logged.  Loggers have created huge slash piles.  They took all the largest trees and left islands of narrow girthed conifers in groups with large meadows in between.  When I walked the logging road, I saw almost no tracks except deer and a few elk, but no squirrels or smaller critters.  Are these the best forest practices in a wild place like the GYE?  Many people I talk to say we need this for fire protection, or we need the lumber.  But control burns are better for the habitat as they suppress invasives that come up after logging, and encourage fire adapted plant materials that fix nitrogen to sprout.  This kind of logging will be good for large browsers, but not for martens and other animals that depend on old growth forests and dense cover.

You can see the slash pile beyond Koda.  This was a heavily forested area before logging

You can see the slash pile beyond Koda. This was a heavily forested area before logging

Weasels and birds

A pair of bluebirds has been nesting here for over a month.  They laid a clutch around May 25 which didn’t hatch until several weeks ago (unless perhaps, when I go to inspect the box, they built a nest on top of the old unhatched eggs).  From what I’ve seen and read, bluebird eggs should hatch within about two weeks so this was very unusual.  I had been checking the 5 eggs every few days, till finally, on June 25, they hatched.

The father is an especially watchful and concerned dad.  He is always checking on the hatchlings, and he was always checking on the eggs too.  Three eggs hatched and lately, as they’ve been growing, the parents have been busy feeding those hungry youngsters.

Concerned dad

Long-Tailed weasel

I just returned from a Bioblitz over the weekend in the Pryors.  I headed out to check my trail camera in the woods and upon my return the bluebirds were really upset, making a big racket right outside their box.  I stood watching fairly close, wondering what the fuss was about.  Then I saw.  A head popped out of their house, and suddenly a long-tailed weasel emerged.  He ran off into a ground squirrel hole quick as a flash. Then I went to check on the babies.  One had fledged and was alive in the grass, but the other two were dead in the box.  If only I’d been a bit quicker I might have scared that weasel off.

I watched the birds for the next several hours.  The weasel returned for his prizes and carried them back into the hole, while the fledgling made his way through the grass uphill into deeper cover.  While the upset parents kept an eye out for the weasel, they also fed and protected their only baby that was left.

fledging hiding in bushes, making it’s way farther from the nest box

Meanwhile a menagerie of other bird species were coming around, interested.  Juncos, a female bluebird, and especially a pair of chipping sparrows wondered what the fuss was about, sometimes helping to scare off the intruder.  One of the most fascinating things was to watch the response of all the neighboring birds over the course of the several hours the bluebirds were upset.

That weasel, or its offspring, may have been the one that ate my pika two years back.  Oddly, he seemed to know exactly when to make his move for the birds–when they were just about to fledge, still helpless yet nice and plump.

mom still feeding the one chick left in the bushes

I rarely see weasels although I know they are around.  But being opportunistic carnivores, they have impeccable hunting skills.  Since I’ve watched this pair of bluebirds year after year, I feel a kinship with them and wanted to drive off that weasel.  I even tried to get my dog to flush him out.  Maybe the fact that the dog and I were gone for 3 days gave this weasel his bold chance.   Yet nature has it’s own ways and my human interference, well-intentioned though it may be, is probably more of the problem than a solution.