The Restless Haystack

A mountain beaver or showtl on the job -- is it making hay or pitching its tent? 

In 1995 Mark Johnson published an article on tents that cover the burrows of mountain beavers.

"Supporting sticks were placed over and across the entrances. Then, sticks were placed perpendicular to these over the entrances. Finally, leafy sticks of big leaf maple (Acer macrophyllum), sword fern (Polystichum munitum), or both were placed across the sticks concealing the entrances." 

The tents were clearly the handiwork of the showtls and not the caring gesture of a passing Sasquatch.

Not all burrows had tents, but Johnson thought they may keep burrows dry in a rainy climate.

Though usually agreeable, showtl enthusiasts have at times disagreed about the animal's tolerance of water.

A pioneering student of the showtl, C. A. Hubbard opined that the rodent shuns watery tunnels, "because Aplodontia cares for water only as  a drink."

Lloyd Glenn Ingles on the other hand averred that, "Living as it often does near water, the animal is a fine swimmer."

Yours truly and his student camera trappers have also given photographic proof that showtls and their neighbors have no qualms about scooting through watery tunnels.

I have the feeling that the showtl's tent may be a drying rack for plant cuttings, that is, nothing more than a haystack, and haystacks have also been reported numerous times in the scientific literature.

The big question is about the criss-cross arrangement of the sticks.

Are they an act of God or an act of mountain beavers?

I've assumed they were an act of God, that they just happened to be there as they had fallen from the trees.

We have actually removed a few sticks from some burrows for better pictures, and if the rodent replaced them with others, I for one didn't notice.

But I am greatly intrigued by Johnson's suggestion, though apparently based on circumstantial evidence rather than direct observation.

A rodent that builds a tent or a drying rack by dragging sticks over its burrow is a remarkable rodent.

It's a tool user.

So confirming Johnson's tent-building observation is on the list for next year's showtl work.

If you haven't seen a showtl's haystack, here's a sequence of 30 photos taken during a week near Yuba Pass, California.

Try to stay awake. It's less than a minute and the action gets exciting at the end.

References

Hubbard, C.A. 1922. Some data on the rodent Aplodontia. The Murrelet 3(1):14-18.

Ingles, L.G. 1965. Mammals of the Pacific States. Stanford University Press, Stanford, California.

Johnson, M.K. 1975. Tent building in mountain beavers (Aplodontia rufa). Journal of Mammalogy, 56(3):715-715.