Friday, March 29, 2013

Look to the Sky

Crusty snow crunched loudly under my skis as I powered up a hill. Although the temperature at sunrise was 15 degrees, it had already risen to 25 by the time I hit the trail. My arms burned as I compensated for the chunky, uneven snow. All my concentration focused down on the gray snowpack, and inside my core.

Then I reached the crest of the hill and looked up. Blue sky and bright sun filtered through every gap in the trees. Immediately, my mood lifted.

Now, I am a naturalist, and not a philosopher or religious scholar, but it seems to me that in both religion and nature we look to the sky for assurance that rebirth will occur. This time of year especially, prayerful folks are lifting their eyes skyward to thank a higher power for a certain ancient resurrection. When the world around us is gray and cold, and it seems like spring might never come, a look to the sky reassures us. That deep blue color, the lengthening days, the intensity of the sun, all signal that the even more ancient rebirth of spring, however slow, is on its way.

Earlier last week, when I started to write this, damp cold permeated the silent woods. Dark trees stood somberly, the live ones indistinct from the dead. I trudged on in melancholy monotony. Then suddenly I became aware of my mood, and the tunnel of gray that had snared me. To break free, I repeated that gesture of looking to the sky, and felt hope return.

During these gray days of early spring, when food is scarce for many in nature, they still put all their energy into creating new life. The squirrels, who have resorted to eating bitter spruce buds, are also chasing each other in a frenzy to reproduce. Foxes and fishers, who might have trouble breaking through crusty snow to access mice, are traveling widely to defend their breeding territories. Whitetail does, and mothers of all kinds, are nurturing their unborn young with the last reserves of their own bodies.

I understand the warblers who return in the warmth of spring to feast on our plentiful insects and raise their young in the bounty of summer. It is harder to comprehend the skunk, who must rouse himself/herself out of his warm burrow in early dawn of spring and traipse across a frozen landscape with the intention of creating new life. How can he/she even be sure that nature will provide warmth and food again?

Animals have this faith built right into their genome. You might also call it instinct, or adaptation.

Plants, too, who stored starches in their roots last fall, who carefully prepared buds many months before spring, and who crafted nutrient-filled seeds in the dog days of summer, have this faith.

Insects are waiting patiently. Long ago, in the shortening days of fall, they found a protected place to hide. Some overwinter as adults, some as larvae or pupae, and some as eggs. The individual may not survive, but the cycle of life continues.

Underneath two feet of dense snow lies a carpet of aspen leaves with little green islands where moth pupae wait for spring. Inside goldenrod galls, the fly larvae have not yet pupated, and still risk death at the piercing beak of a downy woodpecker.

Ticks will soon become active in widening patches of bare, sunny, forest floor.

Wood frogs, still frozen under the snow, are poised to thaw at the first chance. Spotted salamanders wait in their tunnels below the frost line. Their cells contain little bits of algae, who are waiting to emerge into the sunlight and begin photosynthesis.

Loons are in their breeding plumage, and have started moving north. They will fly to the edge of the region of ice, and make forays each day to check on the progression of ice-out. Turkey vultures have already arrived.

If you, too, feel that tunnel of gray ensnaring you, just look to the sky. The cycles of spring restore our faith in the power of life.

Let us hope it will always be like this, each of us going on in our inexplicable ways building the universe.
-- Mary Oliver, from “Song of the Builders"

Friday, March 22, 2013

Saying My Last Goodbyes

Early spring is an amazing time. The sun’s rays are intense enough to melt ice when the air temperatures are still barely above zero. The pussy willow buds are opening, despite blustery weather and forecasts for more snow. Even the buds on the oak trees are starting to swell. Not long ago, I encountered the first skunk wandering hungrily out of his winter sleep. Every beautiful afternoon teases me into thinking about bike riding and gardening.

Yet, I feel like I am saying my last goodbyes after a long visit with an old friend. Every time I ski a trail, I wonder, “Will this be the last time I ski this trail this year?” The animals are feeling spring fever, too, and as they wander farther and faster on the thick crust of the snow, they leave behind a maze of tracks. I also feel sentimental about these, since summer tracking is confined to sandy or muddy edges and those rare soft soils not covered by life.

So, I think, “Is this the last weasel track I’ll see for the winter?  I had better stop a moment and admire the incredible length of its jumps one more time.” “Are these the last fox tracks I’ll see, trotting daintily down the ski tracks and leaving musky scent marks on baby balsam trees?” Maybe I won’t even see many more squirrel tracks, although they seem to last the longest, and pattern every last snow pile with their four-toed front feet and five-toed back feet.

I make sure to savor every moment left of winter. On a recent ski through a friend’s young woods, grouse tracks quilted the crusty snow in lines and loops and spirals. Their tracks went winding around, under, and through the bare, twiggy shrubs. Projections on the sides of the grouse’s four toes, grown just for winter, worked like snowshoes to keep them afloat.

Suddenly, a blur of dark brown rose from the edge of the trail. I had followed the tracks right to the grouse! It must have landed recently, because the trail was short. It began just a couple feet off the ski trail with a sitzmark. Most of us up here think of a sitzmark (one of my favorite words) as “An impression made in the snow by a skier falling backward.” But I first encountered it in animal tracking terminology, referring to the mark made by the belly flop of a mouse or a squirrel as they dive off a tree into deep snow.

The grouse’s sitzmark was just an impression of its belly from a soft landing. A chain of maybe a hundred footsteps led up the bank and into the woods, then ended with an elegant pattern of wing marks where the grouse took flight again.

Soon the grouse will be drumming up love. Soon the snow will be all melted. Soon I will be able to find tracks along the lakeshore in soft sand. Last year at this time it was 75 degrees, the ice was out, I had been kayaking already, violets were blooming, maple and poplar bud-burst had occurred, spring peepers were peeping, maple syruping season had come and gone, and even the lilac buds had burst. Two years ago, I was still skiing in April. You can always count on nature for being unpredictable!

Although I love winter, and try to savor every last bit of skiable, trackable snow, soon the momentum of spring will take over. Each new bit of bare dirt, each swelling bud, each returning bird will push the memories of skiing through restful black-and-white woods further back in my memory. Soon, if you ask me what season is my favorite, I may look up from planting seeds, or smelling a flower, or spying on a warbler, and tell you, “Why spring, of course!”

The Smell of Spring

Warm mid-day sun had softened the snowpack, but a late afternoon chill had refrozen the snow into a hard crust. I crunched loudly down my driveway on snowshoes, thinking about warm soup and a relaxing evening. As I neared the house, a familiar odor wafted toward me. Ah, the smell of Gusto, I thought. Gusto is a scent lure that trapper’s use as a “long distance call.” According to the product description, it will entice red fox, grey fox, coyotes, bobcats, fishers, and martens to check out your traps, which is why the marten researchers staying at our house used it on their hair snares for the past two months.

On my day in the field with Phil and Caroline, the final step in resetting each hair snare was to squirt a generous amount of Gusto in a Dixie cup on a tree above the trap. Did it draw in martens? We’ll only know the answer to that question when Phil analyzes the DNA of the hair samples and sorts out the martens from the weasels and other non-target species that may have investigated the traps as well.

Whether or not Gusto aided Phil’s research, it left a strong impression on us. According to the Gusto sales pitch: “When you crack the cap, you will certainly smell skunk but underneath you will detect a sweet odor consisting of a generous dose of castor and muskrat musk. To top it off, Gusto contains 'special agents' and it is put up in a thick base so it hangs in there for a long time.” And boy does it! We could often smell the pungent odor from the very end of our long driveway. On warm days especially, it seemed to radiate from the researcher’s work truck. It wasn’t entirely unpleasant, but definitely unusual.

But Phil and Caroline left a couple days ago now, and to have the scent of Gusto linger that long seemed a little outrageous. Back at the house, I took off my snowshoes and headed toward the front door. The smell intensified, which seemed unusual since I was walking away from where the truck had parked. I paused for a moment to contemplate this.

Then I glanced down at a cardboard box on our patio, rakishly tipped on its side. The box had once held deer legs or hides that Katie is preparing for our Deer Camp exhibit that opens May 1. Just then it held a very fluffy black tail with white highlights along the outer edges. Of course! It was an actual skunk that made my driveway smell like skunk!

The stark white and black coloration of skunks is not necessarily camouflage for their nocturnal endeavors. Instead, its protective function is to warn potential predators of its distastefulness. Similarly, the bright orange color of a monarch butterfly warns birds of their toxicity.

The books all say that when a skunk is threatened, it first tries to run away from the predator. Well, this skunk just buried its head deeper inside the box. (“If I can’t see you, you can’t see me!”) Luckily for me, striped skunks usually do not discharge the foul smelling contents of their scent glands unless mortally threatened. When faced with danger they arch the back and erect the tail and turn its back on the predator. It may also stomp its feet.

When mortally threatened they bend into a U-shape with both head and rump facing the enemy. They then emit two streams of fluid from scent glands located just inside the anus, which meet after travelling about a foot, finally spreading into a fine spray that can travel up to 15 feet.

This defense works pretty well against mammals with a well-developed sense of smell, so skunks are rarely preyed on by foxes, wolves, or badgers. Large birds are not bothered, though, and great-horned owls are skunks’ main predators.

Though they do not support a diversity of predators, skunks themselves enjoy a wide variety of prey. Insects compose about 70% of their diet, and skunks are one of the main predators of bees. When attacking a bee hive, they wait for the angry bees to emerge from the hive, then bat them out of the air and eat them.

Since bees and other insects, earthworms, snails, frogs, bird eggs, berries, and nuts are all in short supply right now, it is a little surprising that skunks are even awake. But skunks aren’t true hibernators in the first place, and I’ve seen skunk tracks (probably from a restless male) even in January during a thaw. These days, chickadees, great-horned owls, and eagles aren’t the only ones getting a little amorous. Skunks mate from mid-February to mid-April, and naturally become more active during this time.

Skunk’s 4-8 babies will be born in May or June. They are hairless, but somehow already have their striping pattern. Although it takes 22 days for their eyes to open, the little tykes can supposedly spray their musk after just 8 days. It seems fitting that an animal who scientists call Mephitis mephitis, which means “a poisonous or foul-smelling gas emitted from the earth,” would live up to its name right from birth. Ah, the smell of spring!

For over 44 years, the Museum has served as a guide and mentor to generations of visitors and residents interested in learning to better appreciate and care for the extraordinary natural resources of the region. The Museum invites you to visit its facility in Cable at 13470 County Highway M. The current exhibit, STAR POWER: Energy from the Sun, opened in May 2012 and will remain open until April, 2013.

Find us on the web at to learn more about our exhibits and programs. Discover us on Facebook, or at our blogspot,

Furry Little Monsters (or Squirrels Just Have to Eat!)

The vivid blue sky was starting to fade into a rainbow sherbet of color as the warm spring sun sunk toward the horizon. Crusty snow made for fast and challenging skiing, especially where the afternoon sun had shone strongest, resulting in a glaze of ice in the tracks. It took all of my balance and guts to get down the steep hills safely. Naturally, while out on this ski, I encountered something I thought would make a good story!

On a gentle slope through a stand of spruce, suddenly the skiing wasn’t so fast anymore. Hundreds of little spruce branch-tips littered the ground, and of course, they seemed to congregate right in the ski tracks. Sticking and stumbling down the hill, I cursed the furry monsters that ruined my skiing.

Boy, those furry monsters have been busy! Hemlock branch twigs also littered the ground along the Forest Lodge Nature Trail where I was out snowshoeing, and ski trails all over the area have been sprinkled with green through every spruce and hemlock stand. I guess I can’t really be too mad at the furry mon….er….red squirrels. Spruce and hemlock buds are not their preferred food, but at this time of year, the supply of pine and spruce cones is dwindling, acorns are trapped under crusty snow, and squirrels just have to eat. So eat they do, by nipping off a branch tip, turning it around, nibbling off the bud, and throwing the rest right onto my ski trail.

Red squirrels are highly selective in their foraging behavior, harvesting cones from the tree species with the highest seed energy per cone first and systematically working their way through species of conifers by energy density per cone. As spring progresses and hunger gnaws, squirrels will also dine on poplar buds and catkins, elm buds, and maple buds. They will even drink a little sap from the maples once they have opened a wound. Mushrooms are another favorite food.

As the days lengthen, red squirrels also begin to think amorous thoughts, and you may notice evidence of their scramble competition mating system. Males typically invade the territory of females in estrus and pursue them in obvious mate chases. During mate chasing, a single dominant male actively pursues a female and drives off other subordinate males using calls or direct chase. Timing is important, since she will only be receptive for a single afternoon. Keep your eyes and ears open for signs of this wild scramble in the woods.

Nesting sites are located within 30 meters of a cone cache. Red squirrels are highly territorial, with their food cache, called a midden, as the center of focus. Caches help female squirrels assess the resources available for reproduction and weather years of low cone production. You have probably noticed a red squirrel vocally defending its territory with its full repertoire of rattles, screeches, growls, buzzes and chirps. Because red squirrels often cache all their food in a single midden, they must defend it more fiercely than gray squirrels, who have many smaller, dispersed food caches.

As you might imagine, not every cone in the cache will be eaten. Red squirrels use their great sense of smell to locate buried middens--even under four meters of snow! But the death of the owner or other circumstances can lead to middens being abandoned.  When this happens, some of the seeds are left to germinate.

Planting seeds is not the only service a squirrel provides to the forest. Fungi that help young trees acquire nutrients and grow are spread through caching as well. In addition, as squirrels nibble off the buds of conifers, this can cause the trees to grow multiple tops. While this is bad for the tree and timber value, it provides nest sites for a variety of birds and mammals and keeps forest diversity high.

So, while I might curse those furry monsters for slowing down my skis, I can still appreciate that they are an important part of the forests I enjoy so much.

For over 44 years, the Museum has served as a guide and mentor to generations of visitors and residents interested in learning to better appreciate and care for the extraordinary natural resources of the region. The Museum invites you to visit its facility in Cable at 13470 County Highway M. The current exhibit, STAR POWER: Energy from the Sun, opened in May 2012 and will remain open until April, 2013.

Find us on the web at to learn more about our exhibits and programs. Discover us on Facebook, or at our blogspot,

Friday, March 1, 2013

American Martens

The American marten (sometimes known as the pine marten) is the only mammal remaining on the Wisconsin’s state endangered species list. Even when they were more abundant, people rarely caught a glimpse of this shy, solitary, nocturnal weasel.

Until the 1920s, American martens were widely distributed throughout the dense conifer and hardwood woodlands of northern Wisconsin. Unregulated fur harvest and habitat loss caused their demise. In 1986, a marten recovery plan was developed with the goal of reestablishing two self-sustaining populations of martens in the Chequamegon-Nicolet National Forest. But even with cooperation between the Wisconsin DNR, the US Forest Service, and the Great Lakes Indian Fish and Wildlife Commission (GLIFWC), marten populations in the Chequamegon National Forest are not rebounding as well as wildlife managers and researchers hoped.

Over a period of 15 years, 300 martens were released in the Chequamegon-Nicolet National Forest with limited success. Marten populations in the northeast part of the release range on the Nicolet side have grown to about 220 animals, and appear to be holding their own. Unfortunately, the number of these mink-sized weasels in the Chequamegon side of the forest appears to be lower.

Phil, a wildlife researcher and PhD student at the UW-Madison, is studying martens in northwestern Wisconsin. Not long ago he was doing research out west and seeing wolverines (martens’ largest cousins) on mountains. Today, he’s gathering DNA samples from hair traps to determine if the local martens are breeding with reintroduced martens.

Phil and his research technician, Caroline, are staying at the Museum’s Jackson Burke House during their winter research period, so I tagged along on their weekly trap line check to learn more. We skied about 10k in a morning, skimming along groomed snowmobile trails north of Clam Lake. Using GPS units, we navigated to the traps. After getting close as possible on the snowmobile route, we removed our skis and slogged off-road through deep snow to the trap location.

At each site, Phil or Caroline dug the trap out from beneath a fallen log and checked to see if something had tripped it. The hair traps are homemade, and consist of a wire brush fixed inside a PVC pipe about 2 feet long and 5 inches in diameter. The trap is baited with a little wire ball of food and squirt of strawberry jam. When an animal (usually a marten or another small weasel) goes in, it must pass the wire brush to get the bait and again to exit. The researchers who designed the traps did not intend for them to capture live animals. Instead, a wire brush just catches some hair, and that provides the DNA that researchers need.
By comparing the DNA of the hairs they capture to the DNA on record from every released marten, Phil will be able to tell if there has been any romance between the old and the new. Along with habitat and tracking data, this may help researchers tease out the reasons that martens aren’t doing as well as we’d like.

With a slew of traits that prepare martens for survival in northwoods winters, you would think they would be doing great. Small bodies and relatively large feet allow American martens to travel easily over snow. When the snow gets really deep, martens tunnel through snow to reach prey and to den under/in downed logs. These adaptations give martens an advantage over their competitors — bobcats, fishers, and red foxes. Not only do they help martens catch food, it helps them keep from becoming food!

DNR Wildlife Biologist Jim Woodford explains, "Martens do better during years of high snowfalls in the north where they tunnel under snow in search of mice and other rodents. When there is less snowfall, as we have seen in the last few years, they are at a disadvantage."

Unfortunately for martens, most climate change scenarios for the next 45 years in Wisconsin predict reduced snow pack conditions. This would substantially decrease the advantage the big-footed/small-bodied martens have over other carnivores during winter, and likely decrease the number of martens. Aggression between martens, fishers, and other carnivores (like red foxes and bobcats) may increase as shallower snow allows the other animals to get around better in winter.

Whatever the challenges martens face, I’m rooting for them, and hoping to catch a glimpse of this rare and fascinating weasel.

For over 44 years, the Museum has served as a guide and mentor to generations of visitors and residents interested in learning to better appreciate and care for the extraordinary natural resources of the region. The Museum invites you to visit its facility in Cable at 13470 County Highway M. The current exhibit, STAR POWER: Energy from the Sun, opened in May 2012 and will remain open until April, 2013.

Find us on the web at to learn more about our exhibits and programs. Discover us on Facebook, or at our blogspot,