Looking for Spring

  C. Chybowski

A guest post by KVR Educator Cathy Chybowski

Spring is in the air!  Even if the calendar says “March,” the cold winds blow, and the snow lingers, those of us tuned in to the changing seasons know that spring is fast approaching. By observing and recording natural events year after year, we can accurately predict and anticipate the sequence in which these events occur. 

The study of recurring natural events like the migration of birds or the flowering of plants and their connection with each other as the seasons change is called phenology.

Everyone practices phenology whether they realize it or not—naturalists, gardeners, farmers, and homeowners, among others. “April showers bring May flowers” is pure phenology.

Islay Pictures Photoblog

What tells you that spring has arrived? Is it the first robin of the year? Like Aldo Leopold, many people sense that spring has sprung when they see and hear a flock of geese flying in the typical V-formation proclaiming the change of season. 

 “One swallow does not make a summer, but one skein of geese, cleaving the murk of a March thaw, is the spring.”          

Leopold continues .  .  .  .  “A cardinal whistling spring to a thaw but later finding himself mistaken, can retrieve his error by resuming his winter silence. A chipmunk, emerging for a sunbath but finding a blizzard, has only to go back to bed.  But a migrating goose, staking two hundred miles of black night on the chance of finding a hole in the lake, has no easy chance for retreat. His arrival carries the conviction of a prophet who has burned his bridges.”

     Greg Gillson

 Sid Hamm

It is time to check last year’s phenology records for the order of events. We can predict that in southern Wisconsin, the red-winged blackbirds return to the marshes before the end of February and the bluebirds return to nest by March 15. The wood frogs begin their choral courtship the third week in March and ground squirrels and woodchucks emerge sleepy from hibernation by the end of March.  Hepatica begins to bloom around mid-April  and bloodroot blooms about one week later.

                                                                                                                                     awaytothgarden.com

                 C. Chybowski

Nature’s grand production runs from the time that skunk cabbage pokes up through the snow, through the time when the woodpeckers begin to drum, male red-wings “onk-la-ree” from the cattails and pussy willows fluff out. Killdeer and meadowlarks return, chipmunks awaken from their winter dormancy, song sparrows sing “hip hip hooray guys, spring is here,” balls of garter snakes appear, painted turtles pop up on sunning logs, mourning cloak butterflies and little brown bats flit about, and spring ephemerals emerge from the woodland floor.

   V. Charney

All of these observations were made before April 15^th.  Soon thereafter the great wave of warbler migration begins (about a month after the woodcocks begin their aerial courtship display). Then the tree leaves burst forth, flowers in gardens and fields bloom and the air holds the sweet scent of lilacs just in time for Mother’s Day. The show continues on and on . . .

“During every week from April to September there are on average, ten wild plants coming into first bloom. . . No man can heed all of these anniversaries; no man can ignore all of them.”                                                                                                                                                       -   Aldo Leopold

No two years are exactly the same and some signs of spring are more reliable than others. Frogs are good predictors of spring. Wood frogs and spring peepers begin to sing soon after ice-out when the water has warmed to 46 degrees F. Earthworm castings become visible when the frost has come out of the ground. The return of robins and bluebirds is not a reliable indicator of spring because some of them stay in our area throughout the winter.

                                         petponder.com

            

Spring usually invades our state in the southwest corner and marches north and northeast at a rate of about fifteen miles a day. This was determined when residents across the state were asked to record the date at which the lilac, a species familiar to everyone, was in peak flower.

According to Hopkin’s law, phenological events vary at the rate of one day for each fifteen minutes of latitude, 1.25 days for each degree of longitude, and one day for each one hundred feet of altitude, being later northward, eastward, and upward. When applied in Wisconsin, this law seems to hold almost exactly along a north-south axis; except that Lake Michigan retards the spring warmup.

Above is merely a sampling of the discoveries that await the curious nature observer. It is a fun time of year for each of us to get outside and take a closer look at what Aldo Leopold calls the “hundred little dramas” happening right outside the door when spring is in the air. 

Solstice: Celebrating Winter

Mid-winter or Solstice (December 21) is upon us. Here in Wisconsin the sun is already setting at 4:30pm and not rising again until 7:30am.That's a loooong winter night! Winter Solstice, the time of nature's darkness, has long been celebrated by humans around the world. In Northern climates celebrations often include fire and light to signify welcoming back the sun, and turning toward the renewing days of spring.

While the nights are long, the days of mid-winter in Wisconsin are often sunny and bright.  Taking long walks in the winter sunshine can be rejuvenating and so very interesting. What do you see, hear and find? Where are all the animals and what are they doing to stay warm?  Where do they shelter and what do they eat? How are the trees living through the cold?

To supplement your winter wonderings (and wanderings) you might check out these amazing books. There are some for adults and some for children.

Winter World by Bernd Heinrich

Stokes Guide to Nature in Winter by Donald Stokes

The Longest Night by Marian Dane Bauer

Dear Rebecca, Winter is Here by Jean Craighead George

The Shortest Day by Susan Cooper and Carson Ellis

Indoors there are many ways to continue to observe nature. A favorite is feeding and watching the birds outside your window. Young children can have an up-front seat to bird observation in the comfort of their homes. Many hours can be spent observing the ways that birds use their beaks to eat seeds, how they preen their feathers and how they chase away intruders at the feeder! KVR Instructor Barb Duerksen wrote a great post with tips and reminders about bird feeding back in October.

Collecting bits and pieces of nature and bringing them inside can be another wonderful way to observe and explore winter in the warmth of your home. Create an ever-changing seasonal nature table in your home! For more about creating nature tables, check out The Nature Corner: Celebrating the Year's Cycle with Seasonal Tableaux by M.V. Leeuwen and J. Moeskops.

Stargazing after the sun sets continues to delight during the winter season. Tonight, if the skies are clear from your corner of the world, check out this rare event with Jupiter and Saturn that is happening on solstice. If skies are cloudy in your area, there is a livestream available on the link. KVR Instructor and Astroeducator John Heasley also wrote about Winter Solstice Great Conjunction here. 

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The Learning Outside blog will take a break until the week of January 11, 2021. We wish our readers everywhere opportunities to notice and appreciate the light of the new season. Thank you for joining us in 2020.

Animals Toughing It Out: Resisting the Stresses of Winter to be Active, Part 2

                                    Guest post by KVR Instructor, Cathy Chybowski

            Photo of Ruffed Grouse Courtesy of EEK! Wisconsin: Environmental Education for Kids eekwi.org                                 

Like animals that migrate or hibernate, animals that are active in the winter have evolved key adaptations that help them avoid or confront harsh conditions. An adaptation can simply be making use of fur, fat, or feathers. Mammals grow heavy undercoats and long hollow guard hairs to trap air for better insulation. Birds can fluff out their feathers or tuck their heads under their wings for warmth. A grouse spends the day foraging and filling its crop with food. Then it dives or burrows into deep snow, slowly digesting its food, warm beneath a blanket of snow.  

Animals living farther north tend to have larger bodies and smaller appendages. A large body loses heat more slowly than a small body. Shorter appendages radiate less heat than longer ones. Many animals living in the north turn white in winter. The obvious advantage is camouflage for both predator or prey. But another advantage is that white feathers and fur contain more air than pigment so provide better insulation than fur or feathers with color. In summary, it is better to be big and white in winter. Think polar bear! It has a large body, short ears, tail and legs, and white fur. It is perfectly adapted for living in a cold, snowy landscape.

Snow is a mixed blessing. For small mammals like voles, it can provide both insulation and protection from predators. For animals like deer, it can make travel difficult.

The meadow vole, sometimes called a field mouse, spends most of the winter under the snow in a system of tunnels leading to a communal nest. It is an exception to the “better to be big and white” rule.

Photo of Meadow Vole courtesy of EEK! Wisconsin: Environmental Education for Kids eekwi.org 

To compensate for its small size and brown color, it actually loses weight before winter in order to reduce its need for food. Because it is an important part of the food web, it seldom ventures above the snow. Still, foxes and coyotes hear voles moving under the snow, jump up and down to collapse their burrows, trapping them and then retrieving them. Two to three months before the snow has melted, still snug and protected, voles begin to reproduce. A young female can mate at one month of age and produce as many as 17 litters per year with 5 or more young per litter. Look for the tracks of these small mammals on top of the snow or the quarter-sized entrance holes to their tunnels beneath the snow. As the snow melts, the topless tunnels reveal well-traveled runways beneath.

The white-tailed deer is an energy conservation specialist. Whenever possible, it does not expend more energy than it takes in. It grows a thick, woolly underfur and an outer fur with long hollow guard hairs for insulation and it relies on fat reserves built up in the warm months to fuel its activities in the winter. When the snow is deep, deer yard up and follow well worn paths to evade predators and conserve energy. Their digestive system changes to accommodate a change in diet—grazing in the warm months to browsing in the winter months due to the snow cover. When you are outside, look for deer browse, tracks, scat, beds, buck rubs, or antlers usually shed in late winter.

Photo of White-Tailed Deer Courtesy of EEK! Wisconsin: Environmental Education for Kids eekwi.org 

As a group, birds face three obstacles to winter survival: cold temperatures, starvation, and predation. Birds have a higher metabolic rate and a higher body temperature than mammals, therefore making surviving the cold more difficult.The food supply is diminished and often unreliable. Snow can limit access to otherwise available food.  Predators are ever present.  Small birds like chickadees, nuthatches, kinglets, brown creepers and titmice join mixed flocks. More eyes reduce the possibility of a predator attack and broadens the search for food. Sometimes these flocks even roost together in a tree cavity, bluebird nest box, or other shelter. Some birds like blue jays, chickadees and nuthatches store food for later consumption and many birds frequent our feeders when the weather turns harsh or there is deep snow cover.

The black-capped chickadee is another exception to the “better to be big and white” rule. In order to maintain its body temperature in winter, it requires 20 times more food than in the summer.  How do they do it? Among the chickadee’s amazing physical feats is its ability to forage while hanging upside down and moving every which way, foraging for eggs and larvae of insects in bark crevices. Could this acrobatic method be an adaptation for winter feeding when snow covers the tops of branches, chickadees can still gather food from beneath?

Photo of Black-Capped Chickadee courtesy of EEK! Wisconsin: Environmental Education for Kids eekwi.org 

Unlike mammals, birds do not grow extra feathers for warmth in the winter.  Instead, they fluff their feathers to trap more air for added insulation, often tuck their heads under their wings, and huddle together under an evergreen bough with a snowy canopy.  

Aldo Leopold writes in A Sand County Almanac: “I suspect that in the chickadee Sunday School two mortal sins are taught: thou shalt not venture into windy places in winter, thou shalt not get wet before a blizzard.” Apparently a chickadee survives a frigid 16-hour night by doing lots of little things just right. As these tiny creatures wake with the sunrise, they begin foraging and this becomes the order of their day. By late afternoon they are “bulging with fat” which provides insulation. As the sun sets they lower their temperature as much as 15 degrees, settling into a nightly hypothermia, fluffing, tucking, and huddling till sunrise again, when the fat is depleted. Repeat. Repeat every 24 hours; it is a matter of survival. When you are out, listen for the chickadee’s voice and watch for their quick movements.

The next time you reach to turn the thermostat up, think about the challenges that animals face for winter survival and some of the amazing adaptations and strategies they have evolved to deal with them.

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We love the resources at EEK! Wisconsin, Environmental Education for Kids. They are hosting a live reading on December 2, 2020, at 10 AM CT, by author Laureanna Raymond-Duvernell from her book, Under the Mud, about 10 different animals and their winter survival adaptations. For more information or to register visit https://www.eventbrite.com/e/story-edventure-read-aloud-under-in-the-mud-tickets-127366770439 This event would be great for students in grades 3-8, and it is free. Educators are encouraged to register for their classes. Homeschooling and schooling-at-home families might enjoy this, too!

How do they do it? Part 1

Guest post by KVR Instructor, Cathy Chybowski

As the days become shorter and the temperature drops, animals have three options in order to survive: migrate, hibernate or remain active. These strategies along with essential adaptations help animals to survive the cold season.   

 photo credit: freepik.com

Migration: An Easy Out?

Migration can be quite risky. The energy cost of migration is high and there can be many obstacles along the route. Most animals spend time in a feeding frenzy prior to migrating. This added fat will fuel their movement to an area with sufficient food. For hummingbirds, warblers, flycatchers and other birds that lose their food source with the onset of winter, migration is a necessary risk. Large bodies of water, a changing food supply, predators or hunting can make the trip challenging.

Did you ever wonder why it is mostly birds that migrate? Why so few mammals? According to Peter Marchand in his book, Life in the Cold, a mammal would expend ten times more energy moving a given distance by running than would a bird of equal weight flying that same distance. Bats and caribou are exceptions. For more information on bats and insects that migrate see a previous post I shared in August.

Hibernation? Dormancy? What is the difference?

Dormancy is one of the three strategies animals evolved for winter survival. It is a period of inactivity in which an animal’s bodily functions are slowed down. By definition, hibernation is an extreme form of dormancy. Woodchucks, bats and jumping mice are among the few mammals in our state to hibernate.  

 photo credit: WI DNR

As an herbivore, the woodchuck’s life is centered on the availability of plants. Feeding heavily during late summer into fall, it accumulates thick rolls of body fat and then retires to its burrow usually by the end of October. While hibernating, its heart rate drops from 75 beats to 4 beats per minute, its body temperature drops from 90 to 38 degrees, and it breathes once every 5 to 6 minutes. If the woodchuck can maintain this state of low metabolism for several months without freezing to death, it will usually emerge from its burrow during the first week of March (not like Punxsutawney Phil on Feb. 2). 

There are degrees of dormancy, from the true hibernation of the woodchuck at one extreme, to the deep sleep of bears and chipmunks, and to the short term sleep of skunks, opossums and raccoons. In all forms of dormancy, the metabolism slows down in order to conserve energy at a time when food is scarce.

   photo credit: bearstudy.org

Research shows that the black bear does not hibernate; its body does not undergo the drastic changes of a true hibernator. In order to prepare for its deep winter sleep, bears spend the fall in a feeding frenzy putting on several inches of body fat and growing a thicker fur. While in the den, the sow gives birth to 2-3 cubs which do not hibernate either. During this state of dormancy, the bear does not eat or drink, it does not produce waste and it does not lose bone or muscle mass despite the lack of exercise. How do they do it?  These unique adaptations are of interest to medical science. There is more to learn about black bears—how is it that they can survive a 5-month rest and fast and emerge from their den with a 99% survival rate?  Apparently there are few people willing to crawl headfirst into an active bear den in the winter to see just how cozy everything is in there!

    photo credit: WI DNR

Chipmunks spend much of the fall collecting seeds and nuts for storage in their underground burrow where they spend most of the winter in dormancy. The stored food gives them the option of waking and being active for a time; I was surprised to see a chipmunk out and about during a January thaw. No true hibernator could do this.

  photo credit: WI DNR

Unlike mammals, reptiles and amphibians are cold-blooded. Their options for winter survival are few. Since their body temperature drops with the outside temperature, they will freeze to death if they do not hibernate or go dormant in some form. Most frogs and turtles hibernate in the mud at the bottom of the pond or lake. Wood frogs are an exception, burrowing under damp leaves and into the soft soil of the forest floor. The wood frog produces an antifreeze which prevents its cells from freezing. Much of the body fluids outside the cells will freeze as will the frog’s eyes and brain. Its heart and lungs will stop. This “frogsicle” looks lifeless, but with the arrival of spring, it thaws quickly and is the first frog to emerge from hibernation. It is no wonder that the first frog we hear calling in the early spring is the wood frog. When the ice recedes and the water warms to 46 degrees, these frogs begin to call for a mate.

Snakes, cold-blooded reptiles, generally hibernate in dens or burrows of other animals, sometimes in groups of mixed species.  These are called balls of snakes and it is an amazing thing to see in the spring as these reptiles emerge from their hibernaculum. I witnessed dozens of garter snakes emerging this way one time in southeastern Wisconsin. I happened to be in the right place at the right time.

Stay tuned for Part 2, Animals Toughing It Out, in the weeks to come!