January 12, 2020: The Muskrat Attraction

A couple of light snowfalls this week made for some good skiing as well as providing a good surface for animal tracks.  One ski trip took me up to the Ridgefield Open Space just north of Route 104 in Meredith, where the main animal attraction - based on the tracks in the snow - was a muskrat lodge.

A muskrat lodge in the Ridgefield Open Space.

There were plenty of animals checking out the lodge, which appears occupied based on the open air hole and melted snow where heat from the animals escapes up the chimney.

And those tracks are not from the homeowner, as the muskrat has a plunge hole out the bottom where it can access its den under the protection of water.  Nonetheless, muskrats are significant food sources for many predators including hawks, owls, foxes, and minks.  It's a good thing they have lots of offspring, with two or three litters per year.  In return, muskrats create open water for ducks and other waterfowl:  muskrats are such prolific feeders of aquatic vegetation that they can open up large areas of a swamp, perfect for bird habitat.  [Ref:  New Hampshire Nature Notes, Hilbert E. Siegler, Equity Publishing, 1962]

I recently had a discussion with someone about what muskrats eat in the winter and whether they store food under the ice like beavers do.  I went to find out, and according to wikipedia, they do not.  Their primary food source is stalks and roots of cattails, but also arrowheads, rushes, and other wetland vegetation [Sielger], and a healthy wetland complex has plenty of those available under the ice all winter long.

Lots of vegetation in the Ridgefield wetlands complex.

In addition to lodges, muskrats build feeding stations called "push-ups" made of vegetation that rise up above the water level.  In winter muskrats keep these holes open by replacing the vegetation in the hole every day, consuming some in the process.  [Ref:  Tracking and the Art of Seeing, Paul Rezendes, Harper Collins, 1999]  This gives them places to catch a breath while they're out finding food without having to stay close to their lodge.  I'll look for these this winter when I'm out on the ice.  Below is a muskrat structure in summer which I believe is a lodge due to its size and location on the shore line.

It's hard to remember the lake looking like this at this point in the winter.

You can differentiate this from a beaver lodge which is made of sticks and branches rather than vegetation.

Back on Lake Wicwas I saw many other tracks on land and lake:  fox, otter, mink, fisher, mice....  But the most interesting was this set of mink tracks which came from the exact point I saw a mink pop out on the shoreline last November.

I'll bet there's a mink den in this bank.

The middle of those three tracks led to this:

The obvious question here is why this mink pulled such a crazy stunt.  My guess is a raptor was about to swoop down and grab it for lunch, and at the last moment the mink saw it and made a frantic defensive maneuver.  If that's the case, it was successful, as the tracks continued on, though the spacing of the tracks became significantly longer!

I also followed some otter tracks which told another story, but that's a tale for another day....

And of course, all this was before the January thaw hit on Saturday and made the lake, well, a lake.

Maybe back to skating?

It looked like this just four days earlier.

You know what they say about New England weather.  I must say, it was rather surreal skiing in shirtsleeves at 57 degrees in January.