Good Natured: Counting 'huts' – structures made by muskrats

Hut two, three, four … hut, two, three, four ...

That was the phrase that kept running through my mind the other day as I walked with my friend Lorayne and her friend Gayle.

Now, don’t get me wrong. We hadn’t been recruited by a military group, nor were we even marching (which, admittedly, would be a rare activity among us nature types).

We were, however, counting “huts” – as in structures made by muskrats.

Also known as lodges, these piles of plant parts and mud are quite obvious in our local wetlands at this time of year. Lorayne and Gayle had noticed them on their walks around their Geneva Township neighborhood, and the other day the three of us went out to have a look.

Unlike our other aquatic rodent, the beaver, which is not only larger but also stronger and builds its lodges from sticks and logs, the muskrat creates its huts from nonwoody vegetation such as cattails, reeds and rushes. These animals, which measure about 2 feet long, including a 10-inch tail, gather these materials in mounds that range in size from small – maybe 2 feet high – to large – 4 or more feet in height and 8 feet in diameter.

Once the mound is made, the muskrats will hollow out an interior chamber that can be entered only from the underside, which is under water and a great first line of defense from local predators.

A small hut may hold only one muskrat, a larger one a few more. Regardless of number, any and all occupants are insulated from the elements by the structure’s walls that can be more than 1-foot thick.

As another measure against winter’s harsh conditions, muskrats maintain holes in the ice that provide a small space to breathe and feed. Because the little guys push up debris and leftover plant parts through this hole, these piles (which tend to be smaller than lodges) often are referred to as push-ups.

Besides these assorted marshland structures, muskrats in our area might also, or instead, opt to dig underground hideaways. Like the lodges, muskrat burrows also have underwater entrances but typically are dug when the water is flowing and/or its banks are steep. But unlike the huts, burrows can be very hard to locate; you need to look for other signs such as tracks and scat to know if muskrats are active in stream environments.

I’m not aware of any formal studies that have been conducted in our area, but it sure seems like our local muskrats are enjoying a high point in productivity. And reproductivity, for that matter. While it’s easy to commend, or blame, the animals for their success – they are rodents, after all – it’s really us humans that have (literally) paved the way for them.

Over the past hundred years or so, the majority of our natural wetlands have been drained, filled and otherwise modified in the name of progress. Many of these developments feature stormwater retention ponds with aquatic plants – a mainstay in muskrat diets. And while muskrats still have lots of predators – primarily mink and coyotes – hunting and trapping pressure in our area is virtually nil.

These favorable conditions have contributed to the abundance of muskrats we see today. They also made for interesting banter as Gayle, Lorayne and I marched – I mean meandered – our way around the wetland.

We commented on the size of one hut in particular, which was almost as large as a beaver lodge. We noted the channel the critters had worn in the wetland grasses. We were curious as to just how many muskrats might inhabit that particular wetland complex, which receives a lot of its water from the developments along Randall Road. And we also wondered how many people really notice the muskrats, and the signs of their activity.

That last part, we realized, was just a matter of getting people interested in the nature around them. The signs are all around, and all we really need to do is pay attention.

Make that atten … hut!

• Pam Otto is the manager of nature programs and interpretive services at the Hickory Knolls Discovery Center, a facility of the St. Charles Park District. She can be reached at 630-513-4346 or potto@stcparks.org.