Michigan’s Winter Wonders: Green Frog

Winter weather has arrived in most parts of Michigan by now, bringing dread for some, and excitement for others. But have you ever wondered what’s happening under the snow? Many of Michigan’s reptiles and amphibians search for tunnels or other underground cavities to wait out the cold winter temperatures. Still others might remain underwater, remarkably surviving the long winter months with little to no oxygen!

Such is the case with the Green Frog (Lithobates clamitans), one of Michigan’s most abundant frog species. These semi-aquatic amphibians spend their winters hibernating at the bottom of permanent pools and rivers, “breathing” in oxygen through their skin, occasionally nestled among piles of leaf litter that give off some amount of heat as they decompose, and sometimes can be seen swimming before the water has frozen over, or through clear ice. *A common misconception of hibernating animals is that they spend the entire time ‘sleeping’, when in fact hibernation is rather a period of reduced activity.

a green frog sits on a rock in the water
A green frog rests on a rock at MNA’s Joan Rodman Memorial Nature Sanctuary. Photo by Jodi Louth.

So, why spend the winter underwater rather than on land? Other frogs in Michigan like the wood frog, spring peeper, as well as toads, hibernate in tunnels and under leaf piles. These frogs are able to survive the freezing temperatures because they produce excess glucose which helps prevent freezing of the cells in their bodies, acting as a sort of antifreeze. Green frogs on the other hand, are not able to function in this way, and so they must stay in above-freezing temperatures through the winter.

Adequate winter habitat for these species is a critical part of ensuring their survival to the next season, and threats to that habitat exist – even as the snow flies! For many of us, fall is a time for “cleaning up”, for raking up all the leaves that have fallen (and jumping in the pile), then bagging them up and shipping them off to a community dump site. But this practice robs our yards and natural areas of needed habitat, not only for the insects that overwinter in leaf piles like caterpillars and firefly larvae, but also for the many reptiles and amphibians that call our state home. The leaves provide a “blanket” between the ground and the snow, they provide heat as they decompose in place which also returns essential nutrients to the soil.

There are so many benefits for Michigan nature from leaving the leaves, so skip the fall “cleanup” and enjoy reap the rewards come springtime. Learn more about Michigan’s many reptiles and amphibians, and their conservation needs, with Herpetological Resource & Management at herprman.com, and learn more about the benefits of leaving leaves, visit healthyyards.org or leaveleavesalone.org

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Celebrating Michigan’s Many Bats

Michigan is home to nine different bat species, nearly one-fifth of the total number of species in all of North America. There are many reasons to appreciate bats, from the essential pollination and pest control services that they provide, to the fact that they are the ONLY flying mammal on earth. During Bat Week, October 24-31, 2022, you can help Michigan bats by dispelling some common misconceptions about bats.

  • Common Misconceptions:
  • “Blind as a Bat” – although most bats have small eyes, they can actually see just fine. And with the aid of echolocation, they are able to find fast-moving insect targets at night!
  • Disease carriers – Not only does the U.S. Center for Disease Control and Prevention note that fewer than 6 percent of bats tested were carriers of rabies, the fungal disease known as white-nose syndrome, which is the leading cause of population decline among many North American bats, is much more likely to be transmitted to bats from human interference with their habitat.
  • They ‘vant’ to suck your blood – only one species of bat (found in Mexico and South and Central America) has been known to bite humans, rarely, as they primarily feed on cattle.
Northern Long-eared bat photo courtesy Jill Utrup, USFWS.

Northern Long-eared Bat

Learn more about the critical role that bats play in the ecosystem, and share with your friends and family all the ways that bats are beneficial, by learning more about some of Michigan’s bat species below, and at batweek.org!

The northern long-eared bat is a federally threatened bat with a wide range. Found in 37 states in the U.S., these bats live in boreal forests for summer foraging and roosting, and caves for hibernation.

Although there are many threats to the species including habitat loss due to logging, the predominant threat by far is white-nose syndrome. According to the U.S. Fish & Wildlife Service (USFWS), if this disease had not emerged, it is unlikely the northern long-eared bat would be experiencing such a dramatic population decline. Numbers of northern long-eared bats, gathered from hibernacula counts, have declined by 97 to 100% across the species’ range. The USFWS is currently considering reclassifying these bats as endangered because of the threat of white-nose syndrome. Learn more about this classification process by clicking the link here.

Tricolored bat photo courtesy USFWS.

Tricolored Bat

Michigan’s eastern pipistrelle, also known as the tricolored bat, is so named for the multi-colored individual hairs of its fur, tricolored bats appear uniquely yellow-orange in contrast to other more brown-looking bats. Their “fluttery” flight pattern means that these small bats can be easily mistaken for large moths, according to the University of Michigan.

However, as one of the state’s primarily cave-hibernating species of bat, the tricolored bat has experienced significant population decline over the last 15 years, due primarily to the spread of white-nose syndrome. The fungal disease interrupts the bats hibernation cycle, causing them to become active and deplete their energy before there are available food sources in the spring. Once common across its range, estimates suggest that these bats have seen up to a 90% decrease in population since white-nose syndrome was first detected in 2006. Because of this, the U.S. Fish and Wildlife Service has proposed to list the tricolored bat as endangered under protection of the Endangered Species Act. Learn more about the process for classification by clicking this link.

A Milestone Year

The Michigan Nature Association is celebrating its 70th Anniversary throughout 2022. MNA’s spirited founding generation pioneered the protection of critical habitat for rare, threatened and endangered species, establishing Michigan’s oldest land conservancy and the only one
that serves the entire state. They also laid the foundation for our remarkable sanctuary network, and thanks to supporters past and present, it now includes over 180 sanctuaries in 60 counties. For some plants and animals MNA protects the finest—and sometimes the only—remaining habitat. We protect Michigan nature, we protect it for everyone, and we strive to protect it forever.

Join the celebration by learning more about some of our historical milestones below, and watching our 70th Anniversary video!

Image showing timeline of events in Michigan Nature Association history.
Top to bottom: What started as a bird watching group in 1951 signs articles of incorporation in 1952. In the 1960s, the organization acquires its first 10 properties, including its first Upper Peninsula property. In the 1970s, MNA joins the “Save the Pines” campaign and acquires one of its crown jewels: the Estivant Pines Nature Sanctuary. In the 1980s, Twin Waterfalls Memorial Plant Preserve becomes the 100th property protected by MNA. In the 1990s, MNA creates nearly 40 new nature sanctuaries that will become the most frequently visited. In the 2000s, MNA partners with the Michigan Karst Conservancy to protect the Mystery Valley Karst Preserve and Nature Sanctuary. In the 2010s, MNA is awarded accreditation by the Land Trust Accreditation Commission, and earned its first renewal in 2019. In the 2020s, MNA joins the “Keep the U.P. Wild” Coalition, seeking wilderness designation for more than 40,000 acres of land in the Upper Peninsula. Today, MNA celebrates 70 years of protecting Michigan’s natural heritage.

Seeking Wilderness in Michigan’s Upper Peninsula

photos and story by Lauren Ross, Communications & Events Coordinator

On a busy holiday weekend in late summer, I drove north as many people do, through slow-moving construction traffic, and past backed up lines of cars at the tollbooth on the Mackinac Bridge, continuing on until the number of cars on the road dwindled and the primary landmarks became decaying, abandoned motels and towering rows of pines. From there, turning off the main road onto a dirt road, I followed my GPS to an old forest service road (more two-track than road) up and down hills, and swerving left and right to avoid large rocks. Eventually I reached the end of the road, a big yellow sign on a pole announced “ROAD ENDS.”


At the trailhead a boot brush station informs visitors of the need to “Stop Invasive Species in their Tracks.” Beyond that, a trail is barely visible among the roots and rocks of the forest. I am grateful for the white diamonds nailed to trees that provide reassurance I am still on the path. It’s half-past three in the afternoon now, and the warmth of the sunlight peaks through cracks in the forest canopy. A recently downed tree partly blocks the trail about halfway in, but makes a nice seat as I swing my legs over. I know I am nearly there when I begin seeing blue diamonds through the trees—indicating the North Country Trail.


An old military-style canister rests on a post at the junction, inside are maps and a notebook for trail users to sign. There is a mix of factual information and colorful commentary on people’s treks. I continue straight across the NCT toward an opening in the trees. I have to duck past a few low-hanging branches, but soon come out onto a rock face to see the expanse of thousands of acres of forest, as far as I can see in all directions. A creek meanders through the trees several hundred feet below, and I am struck by the immense silence out on this cliff face. With barely a bird chirping, only a light breeze rattling the leaves overhead, I feel I must whisper to myself thoughts of awe and delight so as to not disturb the peace.


Back on the NCT, I headed in search of a suitable spot to set up my tent. The goal, an amazing sunrise view off to the east, overlooking those thousands of acres of forest. I finally decided on a spot about a mile from the initial overlook and set up my tent a safe distance from the edge of another cliff. Boiling some water to rehydrate my backpacking meal, I watched the long shadow of the ridge I was on extend out over the forest below as the sun began to set behind me to the west. I walked out onto the bluff and watched the nearly-full moon shine brightly in the bluish-purple sky that was becoming gradually darker. Then, with what remained of the day’s light I went to hang my food bag in a tree to keep it out of reach of any bears in the area.

A panoramic view from the overlook near camp.


At 3 a.m. I woke to my alarm as planned and laced up my boots, grabbed my camera, and carefully made my way to the cliff’s edge, my headlamp lighting the way. After setting up my tripod and camera, I turned off my headlamp and let my eyes begin to adjust to the darkness. Faintly in the sky over the ridge to the north, I could see the flashes of light indicating the aurora borealis was active, and so I released the shutter on my camera. “Pillars!” I spoke more loudly to myself now—a measure of security to ensure that my presence didn’t surprise any wildlife in the night. For nearly an hour I watched the lights dance, shrinking and growing and shrinking again in intensity.

The northern lights made a much-appreciated appearance overnight.


At 6:30 a.m. I woke again, the black sky turning gray as it began to regain its blue hue. In the forest below a fog had formed in the cool night air, and as the sun rose up over the horizon it released the moisture from the confines of the tree canopy where it gathered in low spots around creeks and ponds. With the aid of the fog, individual trees stood out in the forest below, and features of the landscape that were previously camouflaged became well-defined. The sun rose up over the nearby ridge, warming my face after a chilly night, and signaling that it was time to pack up and hike out before the day became too hot. But for one last moment, I took a deep breath of the fresh forest air and reveled in all that I had witnessed.

Sunrise from camp.


In Michigan, few places remain where people can experience nature on such a large scale. And though we have been reminded in recent years how important connecting to nature can be for our minds, bodies, and souls, threats continue to arise that could erase those places as we know them. Difficult to ignore were the flashing red lights of distant wind turbines even in this very remote place, a reminder that human-altered landscapes are everywhere. And like a crumpled piece of paper, these places, once altered, can never be the same again. So, they deserve our protection now.

Learn more about a coalition to protect this wilderness area in Michigan Nature Presents: Keep the U.P. Wild