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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Winter’s Tiny Surprises

For many of us, winter in Michigan is known for the calm feeling that snow brings. If you’ve ever spent time in a forest during winter, you know how quiet it can feel. Just a few birds chirping and the trees creaking as they sway in the wind.

But there is much more happening in the snow than meets the eye. In addition to mammals whose footprints you may see bounding through the snow—like rabbits, mice, and squirrels—there are also several much smaller species that you may be surprised to learn, thrive in winter as well.

Snow fleas

No, not the kind that will happily hitch a ride and live on your pets. Snow fleas are actually more closely related to crustaceans but, according to the Farmer’s Almanac, are so-called because of the visual similarity and ability to jump long distances respective to their size much like fleas.

Snow fleas—or “springtails” if you prefer—are an essential part of their ecosystem, helping to create healthy topsoil as they feed on decaying organic matter like leaves. Though snow fleas are active throughout the year, they are much easier to spot in winter as tiny bluish-black dots starkly contrasted against the white snow, especially on warmer days as the snow begins to melt.

Snow fleas gather in a boot print in the snow. Photo by Robb Johnston.

Snow mosquitoes

If you love the cooler months for the lack of blood-sucking insects, you may be disappointed to learn that there is a special species of mosquito active in the winter months. But unlike the mosquitoes we typically see in the summer that feed on humans and animals, the males of the winter species get their sustenance from juices extracted from plants. Their eggs are then laid in pools of melting snow, and the larvae feed on algae as they mature.

(Left) A mosquito on spotted coralroot plant in summer, photo by Gary Hofing. (Right) Snow mosquito, photo by Lauren Ross.

Stoneflies

The larvae of stoneflies live deep in the cool water of rivers and streams, where oxygen is abundant. In the winter months when most other aquatic insects are absent and the surfaces of these bodies of water cool the stonefly is able to reach maturity, mating and laying their eggs over the course of approximately two weeks. As spring turns to summer and the surface water warms again, the hatched ‘nymphs’ enter a hibernation period which keeps them safe from predation so that they can mature when winter returns.

Nature in Michigan is full of life in all seasons. So although it may get quiet and harder to see when the snow falls, there is still much to be seen if you look closely enough. So leave the bug repellents at home and head out to an MNA Nature Sanctuary near you to explore all that Michigan nature has to offer this winter!

Wildfires, hound hunting and snake encounters: this week in environmental news

By Kary Askew Garcia, MNA Intern

Fire blazes in Marquette County. Photo via Michigan Department of Natural Resources courtesy of Great Lakes Echo.

Fire blazes in Marquette County. Photo via Michigan Department of Natural Resources courtesy of Great Lakes Echo.

Every Friday, MNA gathers news related to the environment from around the state and country. Here are a few highlights from what happened this week in environmental news:

Above average number of wildfires predicted by summer’s end (Great Lakes Echo): Despite Michigan’s decline in wildfires down to 86 so far in 2014 from a record high of 315 in 2012. according to the Department of Natural Resources (DNR), the latter half of the year may prove to have higher than average numbers of wildfires.

Hunting hounds attack a wounded coyote. Photo courtesy of MLive.

Hunting hounds attack a wounded coyote. Photo courtesy of MLive.

Video in coyote killing raises questions about ethics and the future of wolf hunting in Michigan (MLive): After the discovery of a brutal video of hound dogs attacking a wounded coyote in Gogebic County, policies on how hound dogs can be used during hunting come into question. Although using these hunting dogs are not allowed when pursuing wolves, they are still allowed for other animals, leaving them vulnerable to hunting hound attacks. Legislators are reviewing the film as evidence in a case to determine the legality of hound use in the particular situation.

John Kerry launches global effort to save world’s oceans ‘under siege’ (The Guardian): On Wednesday, John Kerry launched his new global effort to protect oceans from over-fishing and plastic pollution and climate change. Kerry plans to discuss the topic at the State Department two-day summit June 16 and 17. The State Department said Kerry’s conference will help global awareness of issues surrounding the earth’s oceans.

Road salt changes urban ecosystems in big ways (Conservation Magazine): During the winter, tons of salt is dumped along roads throughout the Midwest. Despite the usefulness of salt on icy roads to make it easier and safer for drivers, it ends up running off into soils on the side of the road and changing their chemical composition. The salt can also find its way to bodies of water, plants and animals, changing the way the ecosystem evolves.

DNR offers tips for residents encountering snakes (Michigan Department of Natural Resources): The DNR has released information to help residents who may encounter snakes this summer. Michigan has 17 species of snakes, 16 of which are completely harmless to humans. To avoid snake bites, the DNR suggests getting no closer than within 24 inches of a snake’s head. Residents are also asked to report any reptile or amphibian sightings to the Michigan Herp Atlas research project.

 

 

Northern Goshawk spotted at Lefglen Nature Sanctuary

By Annie Perry, MNA Intern

Northern Goshawk

Photo by Norbert Kenntner Courtesy of Wikipedia Commons

On January 15, MNA Regional Stewardship Organizer Matt Schultz led a group of 18 people on a hike at Lefglen Nature Sanctuary in Jackson County. While on the hike, the group spotted a juvenile northern goshawk, a bird typically found in northern North America and Eurasia.

None of the hikers were able to get a picture, but Schultz said in an email that several experienced birdwatchers were convinced it was a northern goshawk. They identified the bird by its white eye stripe, accipiter shape, large size, and its long, banded tail.

Though northern goshawks live farther north, finding them in Michigan isn’t entirely unusual. Northern goshawks will fly to the Great Plains and Midwest in the winter if prey levels fall in their native forests. They are an irruptive species—a species that irregularly migrates to another area for reasons including availability of food, suitability of climate and amount of predatory activity. Unlike traditional migrations, irruptive migrations may occur one year, then not again for many years.

MNA has other hikes and winter activities planned this season to help you keep winter restlessness at bay. Be sure to check out one of our upcoming events in your area, and maybe you’ll get lucky and see another neat species like the northern goshawk!

Keep checking MNA’s events calendar for an updated list of our winter events!