The birds were quiet, but a tangle of dead trees squeaked and chirped in damp gusts as we hiked back from High Falls in Tettegouche State Park, Minn. The falls had been gushing, and climbing the stairs near the falls had kept us warm, but now squalls of sleet were chasing us home.
A lump of gray fur in the middle of the trail pulled us up short. The small mammal was about the size of a gray squirrel, but with cute, round ears tucked below their silhouette instead of perked up tall. Like a thirteen-lined ground squirrel, they crouched close to the ground with their tail out long, but with none of the stripes. Head and tail were gray, but the fur on their midsection was a warm brown that matched the dry grass along the trail.
I’d never seen a Franklin’s ground squirrel before, but the previous morning someone posted two images of one to the Ely Field Naturalists listserv, and a lively conversation began about how pesky they can be in lawns and gardens around Ely, Minn., when they nibble on the stems of garden plants. “Aren’t they rare?” I wondered to myself, thinking about a beautifully restored oak savanna near Springbrook, Wis., where the presence of this small mammal is a point of pride for the conservation-minded landowner.
Whether rare or common, Franklin’s ground squirrels have a reputation for being hard to spot—by some accounts they spend up to 90% of their lives underground, either hiding safely in the summer, or hibernating with friends in the winter. The one we saw nibbled on new shoots among the dried grasses beside the trail before vanishing into the brush that had grown up in a patch of forest hit hard by windstorms. We had to skirt a freshly fallen balsam fir while stepping over the dried trunks of past casualties.
On various websites I read that Franklin’s ground squirrels are a species of tallgrass prairies, although they’ve declined as the prairies have declined. In the southeastern part of their range the squirrels are barely hanging on in grassy roadsides and railroad right-of-ways—the same places where a few native plants have escaped the plow. They are rare enough to be listed for special protection in Indiana, Illinois, Missouri, and Wisconsin. And several sources suggested that they belong only in the southern and western portions of Minnesota, in the prairie biome.
So what was this little prairie dweller doing in Northeastern Minnesota?
An article that J.J. Huebschman wrote for the Illinois Natural History Survey Bulletin in 2007 provided some clues. When Huebschman looked through a huge number of historic and recent observations, he found that Franklin’s ground squirrels are “most frequently associated with habitat characterized by a mixture of grassy and woody vegetation, referred to as savanna-like or parkland habitat.” It seems that they like the edges of grasslands—not the wide-open landscape that the word “prairie” typically brings to mind.
I decided to upload my observation to the iNaturalist website, and while I was there, I perused the map of all Franklin’s ground squirrel sightings. Zooming out, I saw a swath of red dots stretching from central Alberta down to the top of Wisconsin, with a couple outliers to the south near Omaha, Neb. and Springfield, Ill. Clusters around several population centers could be a result of more human observers rather than higher numbers of the observed species. But you never know—suburbanites also create edge habitat and grow tender vegetables which could help the ground squirrels survive.
Focusing in on Minnesota’s North Shore, I found quite a few sightings stretching along the lake from Duluth up to Grand Marais, and in a parallel band about 40 miles inland, angling all the way up to a Boundary Waters campsite on the Canadian border. Campsites must count as edge habitat! A circle of observations showed that these “rare” squirrels have been spotted at almost every site in the Baptism River Campground.
Humans have created a home for Franklin’s in other ways, too. The old forests of pine, cedar, and spruce that once darkened the North Shore would not have suited these grassland squirrels. But in the late 1800s, loggers took the big trees and left piles of slash. Huge wildfires with their intense heat destroyed much of what was left, and disrupted the normal processes of regeneration. In their wake, pioneering birch trees colonized the shore with native-but-weedy bluejoint grass beneath—especially between Highway 61 and Lake Superior. Both the thatch of grass and the influx of deer made it extremely hard for new conifers to grow up beneath the birches. Wind events (and human development) in recent decades have torn holes in once-dense forests, creating even more edge habitat.
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| The fur of Franklin’s ground squirrels looks gray due to alternating bands of black and white on individual hairs. Photo by Emily Stone. |
A century ago, I would have been more likely to see a Franklin’s ground squirrel at my grandpa’s farm in southern Iowa. It seems that we were both chased north by the intensity of farming on the former prairies and the decline of wild spaces there. Even though the North Shore has experienced plenty of human impacts, I hope both the Franklin’s ground squirrels and I find it to be a good new home.
Report sightings to the Minnesota DNR here: https://www.dnr.state.mn.us/eco/mbs/sightings.html
And to the Wisconsin DNR here: https://survey123.arcgis.com/share/f57cba58511a4c99b1d1292776b05125
Emily’s third book, Natural Connections3: A Web Endlessly Woven, is available to purchase at www.cablemuseum.org/books and at your local independent bookstore, too.
For more than 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Our Summer Calendar is open for registration! The Museum’s new exhibit, The Wetland Way is now open! Discover how life thrives at the intersection of soil and water, and why we must care for these special places as they care for us. Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.
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