Isle Royale: How did you get here?

Author’s Note: I’m traveling quite a bit over the next month, which means I’ve been reminiscing about past trips. As I jet off to raft the Grand Canyon with a photography workshop, here’s a story from 2015 about my family trip to Isle Royale National Park. Unlike the Colorado River, Lake Superior doesn’t need rapids to make big waves. Enjoy! -- Emily

We heaved our backpacks, loaded with high-energy foods, waterproof tents and warm clothing, onto the ferry dock just as the gray dawn was beginning to break. Waves crashed around the Voyageur II, and gusts of damp wind threatened to steal our hats. The ferry captain came out to greet us, passenger list in hand. We collectively expected him to say something like “All aboard!” Instead, with a bemused smile, he projected his voice over the bluster to the waiting crowd and said “We’re not going.”

At first there was just stunned silence, with a few hesitant chuckles, since he looked like he might appreciate a good joke. But he wasn’t joking, and neither was Lake Superior. Eight-foot waves and 30 mph gusts across a 20 mile expanse of cold, open water are nothing to mess with. “This is your one chance for a refund,” he said, “otherwise be here by 4:45 a.m. tomorrow.”

So, for plan B we headed up to the Grand Portage National Monument Visitor Center. The park ranger at the front desk didn’t miss a beat when we told him of our delayed departure to Isle Royale. “Welcome to a long tradition of people waiting at Grand Portage for good enough weather to start a journey on Lake Superior.”

The voyageurs who rendezvoused here every summer through the height of the fur trade era called Lake Superior “The Lady.” And this Lady makes her own rules. Icy water, big winds, and craggy rocks don’t make for safe or easy travel. Gardens of shipwrecks can attest to that. But rising out of the crystal clear water, 14 to 20 miles from shore, is a bit of an anomaly. Isle Royale, a 45 mile long and 9 mile wide bedrock island, is teeming with life that somehow made the treacherous journey.

The cold, clear waters of Lake Superior separate Isle Royale and all its life from their counterparts on the mainland. The Lake makes the Island. Photo by Emily Stone.

The next morning, with the rough, rolling, cold, wet ferry ride behind us, we disembarked gratefully at the Windigo dock on the southwest corner of the island, joining the many lives already there. After cooking oatmeal in the campground, we hoisted our packs and started off down the trail.

Before long, we met several pairs of hikers just ending their trips. We asked about their route on the island, their hometown, and which ferry they took. In essence, we asked “How did you get here?” Mostly they used the water route, but one couple arrived by air in a float plane. Historically, making winter crossings by dogsled was also common. Isle Royale is not an easy place to get to, or to get around, and yet life surrounded us on all sides. Soon I started asking “How did you get here?” to everything we saw.

While relatively few humans arrive on the island by air, many of the island’s wild residents and visitors arrived that way. The haunting wails of loons drifted up from every lake we passed. Chickadees chattered above us as we hiked, while flocks of cedar waxwings played follow-the-leader between berry-laden mountain ash trees. It’s not hard to imagine how the birds got here, or how the seeds of their favorite fruits got here either.

Fruit-bearing shrubs like chokecherry, mountain ash, and serviceberry are often pioneering species, since their seeds are air-dropped in a packet of fertilizer. The vibrant, red fruits of thimbleberry caught our attention, too, and supplemented our quick breakfast. Slowing down to pick berries left us open to attack, though, from the delicate mosquitoes who once made the dangerous crossing, too.

While the whine of mosquitoes was pleasantly rare, red squirrels scolded us incessantly. A water route seems like the only plausible explanation for the squirrels’ presence. Did the first squirrel on the island drift here on a fallen tree or raft of vegetation? What a frightening ride without a motor, rudder, rain gear, warm sweater, or pack full of food! How many attempted journeys failed – with no refund!? Now the red squirrels have been here so long – separated from the mainland population by that arduous journey – that they are considered their own subspecies: Tamiasciurus hudsonicus regalis.

Red squirrels are one of the few small mammals that were able to make the treacherous crossing on Lake Superior and get to Isle Royale. By their incessant scolding, you’d think that they now own the place! Photo by Larry Stone.

Not just a scolding, but a crashing in the brush caught our attention. Through the dense spruce trunks we caught a glimpse of the hulking silhouette of a cow moose as she vanished into woods. Moose are thought to have swum here from Canada around 1900 during a time of overpopulation on the mainland. And they didn’t have a bowl of warm oatmeal to greet them at the end. The trees they browse were here already, though, having colonized the island (by air or water?) shortly after the glaciers retreated 11,000 years ago.

Having sighted one of the iconic species of Isle Royale, we were now on the lookout for the other: wolves. Large, hairy scat on the trail signaled their presence, as did a few big, four-toed tracks among the boot prints on muddy trails. With only two or three wolves left on the island, that is more sign than I’d dared to hope for. Wolves likely crossed the ice bridge in the winter of 1948-49, and they helped stabilize the moose population for many years. Update: In 2018 and 2019, the National Park Service brought in wolves to help buoy the population. The NPS estimates that 30 wolves now live on the island.

Air, water, ice. It is almost easier to imagine how the 1.1 billion year-old bedrock of this island formed than to imagine how such a diversity of seemingly fragile organisms came to colonize it. Perhaps most telling is that not everything did make it. Bears, raccoons, skunks, porcupines, cottontails, and snapping turtles are notably absent. For humans, too, Isle Royale National Park is one of the least-visited parks in the country, and one of the most costly to visit (measured in time, money, and the discomfort of seasickness). Perhaps I’m biased, but I think that makes the creatures who do get there a little more special.

Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, 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. The Museum is open with our brand-new exhibit: “Anaamaagon: Under the Snow.” Our Fall Calendar is open for registration! Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.

Wonderful Waves

The paddleboards’ fins caught on thick tangles of aquatic vegetation as we pushed through the Lost Creek Estuary near Cornucopia, WI. The open waters of Lake Superior promised easier paddling ahead. Where the stream met the bay, waves and currents had shifted the sand into spits and bars. When my fin dragged on one of them, slowing me to a stop, the busyness of summer suddenly caught up to me, too.

“Can we have a snack?” I called up to my paddling partner Kevin, who turned obligingly and beached himself on the other side of the sandbar. Resting on our boards, munching on granola bars, and gazing down the beach at a string of other people happily relaxing on the shore of Lake Superior buoyed my spirits a little.

Soon we paddled north again, hugging the eastern shoreline of Romans Point. The red sandstone cliffs so common on the South Shore were short here, with birch trees and alder shrubs growing less than a dozen feet above the water. Broad, flat ledges held more sunbathers, and ladders down the steeper parts indicated that this was all private shoreline.

Even after a snack, I was still tired, an ache in my shoulder persisted, and the sun was strengthening at the top of the sky. Finally, I couldn’t stand it anymore. “I’m going for a swim!” I declared, as I tucked my sun hoodie, hat, and sunglasses under the bungies on my board and adjusted the ankle leash. With one hand plugging my nose, I slipped off the board and into the lake.

Cheering and laughing, I popped up from the plunge with a grin on my face. The lake was refreshingly cool, but the top layer was heated by the sun. The slight onshore breeze had pushed all the warm surface water into the bay.

Advocates of cold plunging claim that you need water to be between 50 to 60 degrees Fahrenheit, but I could feel all the same benefits flooding my body and brain. The cold shock released endorphins, which vaporized my shoulder pain and gave me a feeling similar to a runner’s high. My fight-or-flight system released norepinephrine, increasing blood flow to the brain and producing feelings of euphoria. Both the scientific research and my own experience show that cold plunging is a reliable tool for improving energy, focus, and mood.

Refreshed, and thrilled to have the rare chance to actually swim in Lake Superior, I parallelled the shore for a bit until the space beneath a low, sandstone shelf called my name.

Under my fingers, the stone felt rough. This Orienta Sandstone formed just under a billion years ago. After the Mid-Continent Rift tried to rip apart the proto-North American continent, the low area it formed became a catchall basin. With no plants on land to hold the soil, powerful streams broke off chunks of bedrock, carried them into the basin, and washed away all of the less durable minerals until mostly quartz remained. Immersed in the lake who now fills that primeval basin, I could still see the fingerprints of those ancient streams, preserved in the cross-bedding patterns.

Newer patterns clung to the rocks, too, and these were green. Mottled like a snake’s skin, and forked like a snake’s tongue, these simple plants represent another ancient bit of history. Liverworts, a type of spore-producing plant related to mosses, were likely the very first plants to creep out of the sea and onto land over 4 million years ago. Slipping into this mode of “soft fascination” in nature improved my mood even more.

Eventually I climbed back up on my paddleboard so that we could continue around the point. Cliffs rose out of the lake ahead of us and soon towered a few dozen feet above our heads. Millenia of waves had worked their way into weaker layers of rock and then continued to enlarge them grain by grain. Some hollows were still tiny, but others formed deep alcoves. They spoke of the power of persistence. As we rounded one corner, a sea arch with one leg out in the lake framed our view. In another spot, multiple caves had coalesced into a maze we could paddle through.

After hours on the water, we returned to dry land to find food and shade. Taking our dessert to-go, we sat at a picnic table with a view of the lake and remarked about just how restful and healing the day had been. The combination of soaking in sunshine; gazing at and jumping in clean water; feeling awe at the ancient rocks; and admiring the beauty of life, had worked a special kind of magic on our moods.

A little flock of gulls bobbed on the waves just offshore, their relaxed calm bringing us even more joy. As we readied to leave, one of those gulls turned to swim directly toward us. When their feet hit bottom in the shallow water, they kept moving forward until they had walked a few steps onto the sand. They stretched their neck forward, opened their beak, and gave a loud “SQUAWK!”

I’m no expert in the language of birds, but that sure sounded like the bird had overheard our conversation about the healing powers of the lake and all they could think to add was “well, DUH!”

Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, 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. The Museum is open with our brand-new exhibit: “Anaamaagon: Under the Snow.” Our Fall Calendar is open for registration! Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.

Sarah Talks About Lampreys

Sarah Montzka, Summer Naturalist Intern and guest columnist, shows off one of their many interesting finds. Photo by Vi Schafer.

Sarah Montzka is about to start their senior year as a wildlife education major at UW Stevens Point. This summer, as a Summer Naturalist Intern at the Museum, they taught our Junior Naturalist programs, assisted with live animal care, and showed a real talent for finding and appreciating the oddest parts of nature.

The fisheries biologist held up a small tank filled with sloshing water to show us the creature inside. A wormlike silhouette wiggled wildly around the tank. The children squealed with delight at this strange creature, remarking on their eel-like shape and fast, undulatory movement. This was a special day for our Junior Naturalist Program. Some of our partners from the Wisconsin Department of Natural Resources had come to do an electrofishing demonstration for the children, and they caught a northern brook lamprey.

Max Wolter of the Wisconsin DNR shared all sorts of cool fish facts with the Junior Naturalists this summer. Photo by Elliot Witscher

Once, during a college field trip, I got to hold one of these creatures. The lamprey was slippery, wriggling violently between my fingers as they tried to slip out of my hand, but I managed to hold on. I didn’t know then, but I was holding something ancient. Lampreys as a group are very old. Their unique anatomical features place them at a pivotal point in evolutionary time. Undulating curled bodies and strange mouths tell us secrets about the past and future.

Lampreys mouths are their most distinctive feature.

Photo by NOAA Great Lakes Environmental Research Laboratory, CC BY-SA 2.0 <https://creativecommons.org/licenses/by-sa/2.0>, via Wikimedia Commons

To understand the lampreys’ story, we have to venture backward along branches of their family tree to the earliest living ancestors of fish, tunicates. Tunicates are vase-shaped, soft-bodied animals, who live most of their lives attached to rocks along the ocean floor. Their free-swimming larvae have many of the basic characteristics of fish, and are the animal right before lamprey in our understanding of how fish have evolved.

There are no freshwater tunicate species, so you won’t see any in Wisconsin waters anytime soon. You may, however, see a baby lamprey, which is remarkably similar to a larval tunicate! Baby lampreys, unlike adults, don’t have eyes or teeth. After they hatch out of their eggs, baby lampreys burrow into the bottom of the river or lake they hatched in. These young lampreys will stay buried under the earth feeding on algae and microorganisms until they mature.

The lamprey I saw with the children was not a juvenile. The small eyes peeking out at us made this fact obvious. After a minute, the lamprey began to settle, gently attaching its mouth to the side of the tank. This allowed the children to get a better view of a lamprey’s suction-cup-shaped mouth littered with rows upon rows of hook-shaped teeth.

The lamprey’s mouth is one of their most distinctive features. Sharp teeth radiate out in circles around the opening. These teeth are not involved in breaking things down, but instead help a lamprey attach onto different things. Non-parasitic lamprey like the one we found quit eating once they reach adulthood, so their mouth is mainly used for carrying rocks to build their nests in the riverbed.

Check out this Facebook video of lamprey moving rocks! 

https://www.facebook.com/watch/?v=791717496095417 

Parasitic lampreys, on the other hand, use these teeth to attach to their prey. Once attached, the lampreys begin breaking through the skin of the fish. This is done with their tongue, which is covered in sharp teeth. When the skin is broken, they feed on the fish’s bodily fluids. The lamprey’s saliva prevents clotting and ensures a long meal.

This may seem gory, but lampreys are an important part of their ecosystems. The sea lamprey, which was accidentally introduced into the Great Lakes decades ago, is the only one of our 5 species who has a negative impact. They feed on more fish than native lamprey and almost always kill their prey. Fish parasitized by native lampreys sometimes die due to the feeding wound becoming infected, but this does not have a negative impact on fish populations.

As I shared some facts about lampreys with the Junior Naturalists, one of the fisheries biologists prepared to release our lamprey friend. None of the kids seemed particularly interested. They were content to splash around with nets, dragging them through the muck along the bottom of the river in hopes of making a catch of their own. One day they may regret letting the chance to hold something ancient slip through their fingers.

For more than 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. The Museum is open with our brand-new exhibit: “Anaamaagon: Under the Snow.” Our Fall Calendar is open for registration! Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.

Mysterious Moths

A small group of students settled into a circle of chairs and tables in the Great Hall. Tall windows let in the gray light of a passing rain shower and the deep green of hemlock trees. A white screen sat in front of the unlit fireplace, and as the projector bulb warmed up, the first image from Kyle’s slideshow came into focus.

Bright orange lichens caught my eye first. And then white lichens with black circles, all clinging to a forked stick. As I studied the photo, the big patch of dusty green lichen sprouted long, thin antennae, a hairy body, and shimmering green, black, and white scales on their wings. The lichen was, in fact, a moth!

There are quite a few species of lichen-mimic moths, explained Kyle Johnson, entomologist with the Minnesota Biological Survey and instructor for this two-day “Mysterious Moths” workshop held at the Forest Lodge Estate near Cable, WI.

“How many kinds of moths do you think there are in Wisconsin?” Kyle asked, and we went into game show mode, throwing out numbers while trying not to overshoot. “Two hundred!” was the first guess. Then eight hundred. Kyle waited. Finally, Jan Sharp, a volunteer who works with our museum collections went big: “Three thousand?” she offered, feeling a bit outrageous.

“Well, I personally have catalogued over two thousand moth species in Wisconsin, and many species are still unknown to science, so three thousand is probably about right!” said Kyle. He shared a map of his field sites with locations marked from the southern tip of Texas to the northern tip of Alaska, with Minnesota, Wisconsin and Michigan at the center. His next big trip will take him to the Yukon! Our jaws dropped at both the number of moth species, and Kyle’s impressive efforts to both catch and identify them.

Moth abundance is even greater than their biodiversity. In any given ecosystem – even the African savannah – insects are the dominant herbivores. They eat more plants than white-tailed deer or even a herd of wildebeests. And moths (in their larval form, caterpillars) are a big part of that feast.

Many kinds of caterpillars need specific host plants to survive. Monarchs and milkweed are the most well-known example. But for numerous micromoths, Kyle indicated that they were “fern feeders.” By that, he means that the caterpillars burrow into the stem of a fern and munch on the green soup inside. This time of year, if you notice a fern turning yellow when all of their neighbors are still green, chances are that there’s a caterpillar in the stem!

When we went out for a walk later that afternoon, Kyle swiped his net through a pine tree and found several little pine-feeding caterpillars who looked just like the needles, white stripe down the center and all. We discovered other moth larvae feeding between the layers of a common plantain leaf. These are just a tiny fraction of the herbivorous caterpillars in the woods and fields right now who are munching away. They, in turn, feed birds and bats, and many members of the food web.

Pine-feeding caterpillar.

On the pine tree are caterpillars, and on the moth’s family tree there are three main branches. One branch is composed of brightly colored, day-flying moths with slender bodies and little clubs at the tip of their antennae. Sound familiar? We call these butterflies! According to entomologists, butterflies are simply a small group of moths.

Macro and micromoths are the other branches on that tree. Macromoths are more evolutionarily advanced, and are often bigger and showier, too, while micromoths tend to be smaller and more primitive.

But not necessarily less beautiful. As Kyle clicked through his slideshow, we oohed and aahed at the fairy-like form of a micromoth. Their forewings were covered in a pattern of shimmering gold and turquoise scales. Their hind wings were a lovely mauve color with a delicate pattern of veins just barely visible. And all were edged with long, shimmering silver fringes.

“All butterflies and moths have fringes on their wings,” said Kyle, it’s just a question of size.” He explained that the smaller you get, the more that air behaves like a fluid. The fringes both add to wing area and reduce turbulence making it easier to fly. The fringes on monarch butterfly wings are almost invisible. For many micromoths, fringes are the main event.

The main event of the moth workshop came after dark. Kyle hung a white sheet with a mercury vapor lamp across an old driveway. Then he painted fermented banana goo onto the trunks of trees along the drive. Until almost midnight, our little group walked from tree to tree to the sheet and back, with stops at patches of blooming milkweed in between.

From drab lichen mimics to shimmering green wings; micromoths smaller than a grain of rice to underwing moths the size of my palm; we were captivated by the multitudes of mysterious moths.

Underwing Moth

Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, 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. The Museum is open with our brand-new exhibit: “Anaamaagon: Under the Snow.” Our Fall Calendar is open for registration! Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.

Studying Tough but Fragile Plants

Common Butterwort, Photo by Emily Stone.

Last week I wrote about the unique adaptations of Common Butterwort, an insectivorous plant with starfish-like leaves. I had just returned to Artist’s Point in Grand Marais, MN, to see if their flowers were blooming, when I found a square of white PVC surrounding the mossy depression in the rock, and a person looking intently at the plot, notebook in hand. I was so thrilled to find a scientist in action, I didn’t even know where to begin!

Ryan Carlson looks up from his meter-square quadrat where he's counting rare plants on Artist's Point in Grand Marais, MN. Photo by Emily Stone.

Questions tumbled out, and Ryan Carlson explained that he was a master’s student from the University of Minnesota-Duluth, working on a long-term monitoring project with four research sites from Two Harbors to Grand Marais. The plots are designed to study Common Butterwort, Bird’s Eye Primrose, and a little plant called Hudson’s Bay Eyebright, three subarctic species who mostly live farther north. Not wanting to interrupt his field work for too long, I made plans to interview him later over Zoom.

Hudson's Bay Eyebright. Photo by Emily Stone.

A few weeks later, Dr. Briana Gross, an Associate Professor at UMN-Duluth, joined us on Zoom. “We've been collaborating with Dr. Julie Etterson on this project since about 2019 with funding from the Minnesota Environment & Natural Resources Trust Fund,” she said. “We're very interested in these species as the vanguard of climate change for the Arctic. Whatever is happening here is what we expect to see happening farther north, as the climate continues to warm.”

Bird's Eye Primrose. Photo by Emily Stone.

Butterwort, primrose, and eyebright are arctic disjuncts, or northern plants who have been separated from their main populations. How did they get here? Twelve thousand years ago, melting glaciers revealed bare rocks and sediments across the upper Midwest. Wind blew in seeds from Northwestern Canada, the eastern coast of North America, and even from refugia in the Driftless Area. They sprouted into a narrow band of tundra-like habitat, no more than 60 miles wide, that skirted the southern edge of the ice for roughly 1,000 years.

In their book, North Shore: A Natural History of Minnesota's Superior Coast, Anderson and Fischer describe arctic disjuncts as “descendants of botanical pioneers that bear humble witness to a past that lies beyond human memory or record, to the wasting of towering ice sheets, and to the birth of nothing less than the lake itself…”

These plants are tough. They can survive cold, damp conditions, high winds, and a short growing season. What they can’t handle are trees and other plants competing with them for sunlight. So when the climate warmed and new plants moved in, these tundra plants mostly retreated with the ice…except in a few naturally refrigerated habitats like Lake Superior’s shoreline on Artist’s Point. Visitors may curse the summer fog that often envelops Grand Marais, but the plants love it.

My good friend Miriam (age 7) and I check out a very wet columbine flower on one of those damp, cool days on Artist's Point. Notice that Miriam is in full rain gear!  

These plants are rare here – Common Butterwort is a species of Special Concern in Minnesota and Endangered in Wisconsin – because their habitat is rare. In Iceland, they are common in pastures.

Ryan has gotten to know these plants on a personal level. For three years, he monitored individual butterwort plants. He measured the size of the leaves, when they bloomed, when they produced seeds, how big their seed pods were, and what that meant for the number of seeds inside. This summer, Ryan is simply counting how many plants are in each plot. Meanwhile, when back at the lab, he’s analyzing the detailed data to answer questions like, “Does when a plant blooms impact the number of seeds they produce?”

Developing seed pods of Common Butterwort. Photo by Emily Stone.

“It’s very detailed data that we don't usually have for these types of populations,” chimed in Briana. There’s good news and bad news in the data, they told me. The butterworts are producing a ton of seeds – which pop explosively out of their seeds pods – but those seeds don’t seem to germinate and grow into new plants very often. Perhaps they need a perfect storm for germination. And I do mean storm quite literally. On the wave-pounded and ice-scoured shores of Lake Superior, an entire pocket of butterwort might be wiped out in a single storm. Could that somehow stimulate seeds to germinate, too?

A beautiful but fragile cluster of butterwort growing in a patch of moss directly on bedrock, within reach of storm waves of Lake Superior. Photo by Emily Stone. 

Since butterworts usually come back year after year, and can also produce offshoots that grow into new individuals, low germination may not be a problem. “You can be looking at a plant that's smaller than a clothespin,” Briana observed, “and it might be a decade old!

“They're very, very tough,” Ryan added, “but they're very fragile as well. So there's a duality there.”

We can help. Goose poop or careless footsteps from dogs and humans can be devastating in the fragile habitats where butterwort, primrose, and eyebright hang on. Don’t feed the wildlife. Take care to step only on bare rock or gravel when you visit the Lake Superior shoreline. And take a moment to admire the tenacity of these pretty cool plants!



Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, 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. The Museum is open with our brand-new exhibit: “Anaamaagon: Under the Snow.” Our Fall Calendar will open for registration on August 1! Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.