Wednesday, December 29, 2010

Orion

Nature Watch
By Susan Thurn,
Cable Natural History Museum

The longest nights of the year are upon us, but at least we’re past the solstice and days begin lengthening again. With the addition of a new dog in our family, I find myself outdoors at night more often than previously. These walks are pleasurable for in spite of the cold, there is an amazing night sky to greet me. Even in early evening, sky-watching is worthwhile, as Orion, a constellation we see only in the winter, is peeking into view as night falls. Sirius, the brightest star in our night sky, also sparkles in the south. It makes for a lovely view!

Orion, known in historical legend as the hunter, shines in prime time during winter's long nights. It can be viewed in the east soon after nightfall. It is perhaps one of the most easily found and identified constellations we can view. Bright stars make up Orion’s three-star belt. Around the belt at similar distances are four bright stars that make up the outline of the hunter’s body. An orange star named Betelgeuse is Orion’s left shoulder, and a blue star named Rigel is brightly showing Orion’s right foot. Moving down from the belt is a small line of three stars that create the hunter’s sword, although technically the middle star is not a star but the Orion Nebula, which can be seen with binoculars as a glowing cloud of material. Sirius, the bright star to the south, is part of Canis Major, the big dog or big dipper.

Orion, the hunter, stands by other night constellations such as the river Eridanus, is accompanied by his faithful dogs, Canis Major and Canis Minor. Together they are said to hunt celestial animals such as Lepus, the rabbit, and Taurus, the bull. There are many stories in different cultures of how Orion came to be in our night sky with his dogs. In Greek mythology, Orion was in love with Metrope, a seven sister who forms the Pleiades constellation. Unfortunately, Metrope did not return his affections. Orion’s tragic life ended when he stepped on the scorpion, Scorpius. The gods then felt badly for him and put him and his dogs in the night sky, along with animals he could continue to hunt. However, Scorpius was placed far away from Orion in the night sky so that Orion could not be hurt again. Hungarian tradition also calls him a hunter, but believes that he is the father of Hungarians. The Chinese thought the three stars were a top a man’s head. Australian aboriginals believe Orion is called Julpan, a canoe. They tell the story of two brothers who went fishing, and caught and ate a forbidden fish. Seeing this, the sun sent a waterspout that carried the two brothers and their canoe up into the sky. Native Americans from a tribe in California thought that the three stars were the footprints of the god of the flea people. This legend states that when his five wives ran away because they were itchy, three times the god of the flea people looked in the sky for them. When his footprints are seen only in the winter months, the flea people go into hiding, a time when there were no fleas. Sumerians thought the pattern was a sheep, and Betelgeuse, meaning armpit, was the armpit of the sheep.

There is more than just Orion to take a peek at in our night sky this time of year. On December 29, the thin crescent moon rises in the southeast with the planet Venus to its lower left. Our Christmas star, Sirius, rises around 7-8 p.m. and is worth looking at with binoculars, as when it’s low in the sky it twinkles in flashing colors. In early January, Uranus and Jupiter can be viewed with binoculars. These are all sights worth getting outdoors in your own back yard!


For over 42 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 and exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs.

Thursday, December 23, 2010

Balsam Fir

Nature Watch
By Susan Thurn,
Cable Natural History Museum

As we head into one of our biggest holiday weeks, some of my most favorite sights and smells include the lights and the smell of our holiday tree, a beautiful balsam fir. The history of the Christmas tree has many interesting and different stories. The Egyptians might not have celebrated a holiday with a fir or pine, but were part of a long line of cultures that treasured and worshipped evergreens. In fact, when winter solstice arrived, they brought green date palm leaves indoors to symbolize life's triumph over death.

Another balsam fir holiday story is associated with a German, St. Boniface, who cut down an oak tree in order to disprove the legitimacy of the Norse gods to the local German tribe, and was amazed when a fir tree sprung up from the roots of the oak. Another cultural tradition included a tree that was taken to the town market center and lit aflame to celebrate the holidays. Yet another story of the tree includes the decoration of a small tree with nuts, apples, pretzels and paper flowers for the children. Germans and Scandinavians placed evergreen trees inside their homes or just outside their doors to show their hope in the forthcoming spring. No matter what the celebration, today the balsam fir is still a perfect tree as it has the benefit of not shedding its needles when they dry out, as well as retaining good color and scent.

What is special about balsam fir? It’s a great tree to shake hands with, with very soft, individual flat needles. Balsam fir bark is thin, gray, and smooth except for numerous blisters on younger trees. The scientific name "balsamea" is so named because of the many resinous blisters found in the bark. These balsam blisters contain a sticky, fragrant, liquid resin and so they are sometimes called “blister pine.”

A balsam fir provides food and cover for red squirrels, moose, snowshoe hares, deer, ruffed grouse, crossbills, and chickadees. The needles are also eaten by some caterpillars. Porcupines eat the seeds.

The balsam resin has been used to produce Canada balsam, a type of turpentine, and was used as a glue for glasses, optical instruments, and for preparing microscope mounts. It has also been used as a cold remedy and an EPA approved nontoxic rodent repellent. It is a tree of many uses!

I don’t have to enjoy the tree in my living room, as balsam fir grows commonly in the forests around us. Be sure to get outdoors this holiday season and shake hands with a balsam fir!

For over 42 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 and exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs.

Wednesday, December 15, 2010

Mistletoe

Nature Watch
By Susan Thurn,
Cable Natural History Museum


Having just celebrated six months of wedded bliss, this holiday season brings on great feelings of love and opportunity for family celebration. It is a time filled with candy canes, colored tree lights, and mistletoe, just a bit of the many things we can enjoy at the holidays. I’ll never forget the time I was preparing a lesson plan for area schools on symbiosis, a word that describes the relationships between organisms in the natural world. I discovered then that mistletoe is a parasite. Mistletoe, a parasite? I always thought it was so ironic that a plant that brings love and joy into our lives was also a plant that uses other plants as a host by taking nutrients out of the tree. What a surprise!

Mistletoe is a partial parasite, as the plant is still capable of photosynthesis. They have a special root system, called haustoria, which grow down into their hosts. They extract nutrients from the trees upon which they grow.

The common dwarf mistletoe grows in northern Wisconsin. Not looking like most mistletoe plants we hang in our homes, this dwarf plant grows less than 3 centimeters tall. In spite of its size it often causes a very conspicuous irregular growth known as a “witch’s broom.” A witch’s broom is created by the mistletoe as it causes the tree to grow a compact mass of branches that resemble a broom that can reach 3-10 feet in size. Its main host is black spruce, but it also will parasitize red, white, and jack pine and balsam fir.

To some, mistletoe might be considered a negative part of a forest, but actually mistletoe does have some benefits in many ecosystems. The density of the growth can provide habitat to birds and other animals. Some species of mistletoe can cause the host plant to grow more berries, increasing reproductive success and providing food to other animals.

Mistletoe has a history that is rich in human tradition that goes all the way back to Greek culture. Throughout time mistletoe was thought to bestow life, protect against poison, and increase fertility. It was also thought to ward off evil, or bring peace, as well as provide a prediction of happiness and long life. Mistletoe can certainly bring magic to this season’s holiday joy. May you all enjoy a wonderful, festive holiday, and be sure to find your way under the mistletoe!

For over 42 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 and exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs.

Wednesday, December 8, 2010

Barred Owl

Nature Watch

By Susan Thurn,
Cable Natural History Museum

I’ll never forget the time I called in a barred owl using my voice, only to have both the owl and myself experience being dive-bombed by woodpeckers. Or the other time I called in five owls all part of the neighborhood around the house. I’ve been practicing a barred owl call for many years now, and its who-cooks-for-you song is noticeable enough in the forest to make it one of the most-known owls in our northwoods environment. It is with constant amazement and utter respect that I interact with these birds in our area.

A barred owl enjoys a variety of habitats that include deep, moist forested areas, wooded swamps and woodlands near wetland areas, preferring larger forest tracts. Their territory is thought to be up to one square mile of land. Barred owls eat small mammals such as voles, mice, shrews, squirrels, rabbits, and chipmunks. They also will eat birds up to the size of a grouse, woodpeckers, and even smaller owls, and are known to take prey from around bird feeders. They catch birds as prey at dusk when the birds are settling in to roost for the night, as the barred owl cannot usually take them while in flight. They also will eat bats, snakes, frogs, salamanders, mollusks, and insects. They have even been observed wading in water in search of crayfish and fish. In fact, the feathers on the front belly of the barred owl can sometimes have a pink tinge, possibly due to eating crayfish. In winter, barred owls rely on their excellent hearing to focus in on animals burrowing through snow.

Barred owls hunt mostly at dusk and night-time by sitting on a high perch and looking and listening for prey. They then catch their prey during a short flight to the ground. During the day they hide in dense foliage, usually high above us. They also roost on a branch close to the trunk, or in a natural tree hold.

A very territorial bird, barred owls use vocalizations that are more extensive than their familiar who-cooks-for-you. When feeling very territorial, they move from a short bark into a monkey-like call that is amazing to hear. To me these owls represent one of the best creatures of the northwoods. Their beauty, their night call, are all worthy of admiration.

For over 42 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 and exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs.

Thursday, December 2, 2010

White/Black Fur

Nature Watch
December 3, 2010
By Susan Thurn,
Cable Natural History Museum


If the color black absorbs heat, why is a polar bear white? It turns out that dark or black fur isn’t always the warmest fur to have. Energy does come to animals when the sun is shining. This solar radiation penetrates into the fur, some of which is absorbed at the surface, and some all the way to the skin.

Because our winters have less sun, we have less incoming solar radiation, called insolation. Animals living in our region and latitude are exposed to a lower amount of insolation. Black fur absorbs solar radiation well, but even then, much of the energy is redirected back into the environment again, keeping the sun’s heat from reaching the animal’s skin. A contrast to this is white fur, which reflects some sunlight outward, but also reflects the sun down into the fur layer down to the skin. Add to this the thickness of the fur and how those fur pieces lay over each other, this white fur can more successfully warm the skin. Animals that have dark skin with white fur (as do polar bears) increase their ability to absorb heat. How interesting that white fur is not just about camouflage!

How do humans deal with constant exposure to cold? Can we, who live in the northwoods, ever get “used to the cold”? Evidence does show that humans can acclimatize themselves to colder environments, but usually only with prolonged exposures to that cold. Several groups of people have developed very specific adaptations to cold. Inuits, Norwegian fisherman, and Tibetan and Indian yogis have increased circulation and skin temperature in their extremities. Finnish outdoorsmen can have brown fat in strategic locations. Mailmen of Quebec City have lowered blood pressure and heart rates. Antarctic workers have a higher core temperature. Those with yoga training can exhibit a higher cold tolerance.

Sign me up for the next yoga class! And the next time I feel bad about the extra layers of fat around my body, I’ll just think of it as strategically located cold insulators. Whatever it takes, being outdoors, even in the cold, is worth making some adaptations!

For over 42 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 and exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs.

Wednesday, November 24, 2010

Cottontail Rabbit

Nature Watch

By Susan Thurn,
Cable Natural History Museum

One morning this week my husband and I looked outside and saw a cottontail rabbit feeding right outside our window. The little white burst of color we call a tail resembles a cotton ball for which the rabbit is named. The cottontail’s body was covered with a soft pale-gray mixed cinnamon colored fur with black tips. The rabbit living in our backyard was grooming itself, as their fur isn’t waterproof and needs care to keep their hair in healthy condition. Their large, long ears shifted as a satellite dish as they listened to everything around them. All of these observations were made in a few moments, watching this rabbit outside our window.

The sun was not even up yet when we saw our backyard visitor. Cottontail rabbits browse for food at night on grasses and herbs such as clover, dandelions, alfalfa, fruits and vegetables. In winter, their diet consists of the woody parts of bark, twigs, brambles, and buds of birch, oak, basswood, willow, sumac, dogwood and maple trees. Their teeth are adapted for gnawing on plants. Their top incisor teeth keep growing constantly throughout their lives to allow them to keep chewing away at their meals.

Cottontail rabbits live in a variety of habitats from our neighborhoods, orchards, and farms to sparsely wooded or thick brushy areas. They can travel in a range up to eight acres, and can be moving any time of day or night, but mostly during dawn and dusk. They choose areas with good protection and escape routes.

Freeze tag was always one of my favorite games, and it is one that the cottontail rabbit excels at when avoiding predators. Freezing is far more than a game to these rabbits, as they use this technique to avoid predators, avoiding being noticed until the animal gets too close. Then they shoot out like a bolt of lightning, fleeing from their prey with a zigzag pattern, reaching up to 18 miles per hour and leaping up to fifteen feet away in one move. The zigzag movement gives them an advantage as it breaks their scent trail. Sometimes they will also stand on their hind feet to observe predators.

We all know the cottontail rabbit can sometimes be a bit of a scoundrel to us as they chew away our tulips, but they too can bring great enjoyment in our backyards. Be sure to post your own stories on the Nature Watch blog at cablemuseumnaturewatch.blogspot.com

For over 42 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 and exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs.

Thursday, November 18, 2010

Ruffed Grouse

Nature Watch

By Susan Thurn,
Cable Natural History Museum

While walking in the woods this week it happened again. I was meandering along and enjoying the shades of brown and green colors that greet us in the forest this time of year. Suddenly, I was startled and almost jumped out of my skin when a ruffed grouse flushed out of the brush nearby. I enjoy these birds for their beauty, in spite of the scare they often give me. They are difficult to see as they camouflage themselves so perfectly into their surroundings. As they flush out away from me, the sound of their wings beating loudly as they swiftly fly away matches the speed of my startled, crazy heartbeat.

Some fourth graders I know are currently reading the book Hatchet, by Gary Paulsen, which features a ruffed grouse. In the story, Brian Robeson has managed to survive a plane crash in northern Canada, and is surviving this northwoods wilderness with his wits and a hatchet. Brian names the ruffed grouse “foolbirds.” I have to disagree with Brian’s “name,” as ruffed grouse seem to me anything but foolish. The way grouse find food anytime during the year seems very intelligent to me.

In autumn, there is plenty of food available to a ruffed grouse. There are many different fungi, or mushrooms, to choose from, as long as the birds can find them before the red squirrels. Acorns have fallen from trees, and grouse benefit from white-tailed deer who have stomped on the acorns and broken them open to be found and consumed by the birds. The late-ripening berries are for the taking, and its not just the shrubs and other plants we typically think of that have available fruits, but also low growing plants such as rose hips, bunchberry and wild lily of the valley.

In later fall, the ruffed grouse adapts to new food sources as the bird moves from the ground to the trees. Grouse consume the buds of many different trees such as aspen, birch, and chokecherry. It is believed that with the change to higher fiber-filled tree parts, grouse depend more on micro-organisms in their digestive system to aid them in getting nutrients out of their food.

We are fortunate to be able to enjoy the beauty of ruffed grouse in the northwoods. On second thought, perhaps “foolbird” is an appropriate name, because they sure do fool me with their excellent camouflage and ability to hide. Be sure to get outdoors this fall to enjoy looking for grouse in your own back yard.

For over 42 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 and exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs. Post your own stories on the Nature Watch blog at cablemuseumnaturewatch.blogspot.com.

Wednesday, November 10, 2010

Fox Sparrow

Nature Watch

By Susan Thurn,
Cable Natural History Museum

The bird feeders at my parent’s house are still busy in spite of the many migrant birds that have left us for a while. A few glances at the feeder show the less colorful winter plumage of the goldfinch, the slate-colored juncos, chickadees, downy and hairy woodpeckers, white and red-breasted nuthatches, blue jays, cardinals, mourning doves, white-throated and fox sparrows. It was the fox sparrows that recently caught my eye, and ears. A larger sparrow, fox sparrows are bright rust-colored on the tail and wing. There are red, thick streaks on the breast, and reddish streaks on a gray colored back with faint white wingbars. Their lower mandible is colored pink to yellow-orange. These sparrows are a striking bird, and have some additionally interesting behaviors.

Fox sparrows most appealing behaviors are ones to hear, rather than see. They scratch through leaves through insects and seeds, and make so much noise they sound like a larger animal. These noticeable actions come from a vigorous double-scratching as the fox sparrow kicks backward in the litter with a two-footed jump-kick motion as they work to uncover food. This same foraging behavior unfortunately makes them vulnerable to cats and other predators.

The main food choices of fox sparrows are seeds from grasses and a plant called smartweed. They will eat berries as well. During warmer seasons, they also eat insects and feed them to their young. When nesting, adults are known to perform a broken-wing display to lure potential threats away from the nest.

Be sure to enjoy the fox sparrows around your own feeders, birds which are collectively known as a “den,” or “slyness” of sparrows. Enjoy them while you can though, as they spend our winters in the warmer climates of North America. Their migration this season began in early October and by mid-November, only the last few will remain in our neck of the woods. Watch and listen for this last glimpse of color and sound as they scratch around the fall leaves of our northwoods backyards.

For over 42 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 and exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs. Post your own stories on the Nature Watch blog at cablemuseumnaturewatch.blogspot.com.

Wednesday, November 3, 2010

Fall Leaf Decomposition

Nature Watch

By Susan Thurn,
Cable Natural History Museum

“Scrunch,” “scrunch” went the crunch of dry leaves under my feet. The brown, dead leaves have been a delight for many that love to walk through leaf litter while kicking up fall leaves. For others, the leaves are perhaps part of a fall routine as people rake them from their lawns. For nature, decomposition is the natural process for leaves as they fall to the ground, creating new building blocks of life recycled over again. Right now in the forest this recycling is a job filled by invertebrates, fungi and bacteria.

Decomposition of leaves occurs through many different means. Invertebrates and earthworms break leaves into smaller fragments. This process allows the leaf pieces to have more surface area to support the next step of decomposition, bacteria and fungi. Rain also filters through the leaves, dissolving chemicals and nutrients. Bacteria grow better when the leaf fragments are smaller. The organic matter is broken down to carbon, nitrogen and other minerals.

Certain species of fungi also aide with the decomposition of leaves. Fungi hyphae fibers spread through dead leaf litter just under the forest floor, extracting nutrients the fungi need to survive. These hyphae develop into matted carpets that we sometimes see when leaf litter is moved. The speed at which decomposition occurs depends on moisture, temperature and composition of the leaf matter. Lower temperatures make decomposition occur more slowly. Leaves with low nitrogen also slow decay because the fungi cannot gain enough nitrogen from the organic matter to make necessary proteins. Lower oxygen environments also slow decomposition.

Waste not, want not is the perfect description of our leaf decomposers. Without them, nitrogen and other nutrients would be locked in the dead leaves, not leaving enough for living plants and their needs in making new leaves and seeds. Those bacteria and mushrooms are such “fun-guys!”

For over 42 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 and exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs. Post your own stories on the Nature Watch blog at cablemuseumnaturewatch.blogspot.com.

Thursday, October 28, 2010

Turning

Nature Watch

By Susan Thurn
Cable Natural History Museum

Chilly fall days give us a warning that winter is coming, and in response plants and animals (including we humans) adjustment accordingly.

The changing of the season also affects the behavior of bodies of water. You may have heard people referring to lakes “turning” this time of year, and wondered what that means.

It’s a twice-yearly phenomenon related to water and air temperature—here’s how it works: In late summer, lake surface waters reach their annual maximum temperatures. Deeper waters are cooler—in many lakes, there is a definite stratification or layering of water temperatures that you would feel if you were swimming on the surface and then dove down deep. The warmest, least dense waters lie on top; water temperature decreases with depth, reaching its minimum temperature at the greatest lake depths.

In the summer, a deep lake will have three layers in the water column: the upper, warmest water (the epilimnion); a thin middle layer, where temperatures rapidly decrease (the thermocline or mesolimnion); and the deepest, coldest water (hypolimnion).

In autumn, cooler air temperatures and diminished hours of sunlight result in a loss of heat from the lake’s upper water layer. As these waters cool, they become more dense and when they reach about 50 degrees F, they sink into the middle layer below, erasing the temperature stratification that had developed during summer.

Eventually, all the lake water reaches a uniform temperature, and surface winds then mix all the water. When the winds are strong and fairly constant in direction for an extended time, they establish a water circulation pattern—as surface waters are blown downwind, waters from below must rise along the upwind shore to replace those waters pushed across the surface. To complete the circuit, the downwind shore surface waters, piled up by the wind, sink to replace the rising bottom waters.

In time, the resulting circulations will completely overturn and mix all the lake’s water—hence “fall turning.” The phenomenon can at times produce a rotten-egg odor, since the deep waters, which are low in oxygen and high in sulphur, rise to the surface and release sulphurous gases into the air. The turnover also mixes atmospheric oxygen into the lake water, replenishing the oxygen in deep waters and allowing fish to return to the depths where many will spend the winter.

Of course, after the fall turning cools the lakewater and as winter approaches, surface waters approach the freezing mark. Unlike most compounds, water reaches its maximum density as a liquid just before becoming a solid. Under normal conditions, freshwater is most dense at 39 degrees F, and ice, being less dense than liquid water, floats. So as lake waters cool, they sink when they reach 39 degrees. Colder water remains above, and is eventually covered with ice.

In the spring, the cycle happens again in reverse. Ice cover melts, and cold surface waters warm until they reach the temperatures of the bottom waters. Winds blowing over the lake again set up a full circulation system; as warming continues, the three water layers again become established, and a full turn of the cycle is complete.

For over 42 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs. Post your own stories on the Nature Watch blog at cablemuseumnaturewatch.blogspot.com.

Wednesday, October 20, 2010

Northern Pike

Nature Watch

By Susan Thurn,
Cable Natural History Museum

They were trolling the waters for a big fish, the musky. “Fish on,” were the words heard from the boat as the sound floated across the water. It was a decent sized fish, but it wasn’t a musky. Instead, it was the struggle of a northern pike that was brought into the boat. This tooth-filled mouth earns its place as the second largest predator fish in northern Wisconsin.

Northern Pike have a duck bill shaped long snout that is lined with sharp canine type teeth. Their olive-green upper sides are marked with longitudinal rows of yellow spots. This “handsome-looking” fish can live for more than 20 years.

The northern pike is a cool-water species whose habitat is usually warm, slow, and shallow, heavily vegetated rivers or the weedy bays of lakes. They also can be found in cold, clear, rocky water bodies. A solitary and territorial fish, northern pike ambush their predators, laying in wait at the edge of weed beds to dart out, attacking with surprising speed. Young northern pike feed on immature aquatic insects and then fish. Adults will eat fish, crayfish, ducklings, muskrats, frogs, leeches or mice. Northern pike are known for being less particular about their food choices. They will even eat younger pike fish, making it critical for the young pike to find safe shelter among vegetation. Northerns typically catch their prey sideways, immobilizing their prey with the backward pointing teeth, and then turning the prey headfirst so they can swallow it. Younger pike have been found dead having choked on a pike of a similar size.

It may be that the catch and release fishing of my family has been the best way to catch glimpses of a northern pike. A swirl or swish at the water’s surface makes me take a second look, hoping for a view of a fish. These fish are just one of the many enjoyable experiences we can look forward to experiencing in our northwoods back yard.

For over 42 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs. Post your own stories on the Nature Watch blog at cablemuseumnaturewatch.blogspot.com.

Wednesday, October 13, 2010

Slugs

Nature Watch
By Susan Thurn,
Cable Natural History Museum
“I’ve been slimed!” That’s the comment that came out of my mouth this week as I discovered a host of slugs underneath the log I had just lifted. With the rain we have had this summer and fall, the slugs seem to be more easily observed. It is not just their slug trails that are fascinating to learn about.

Slugs and snails are related and are called gastropods. Like other land snails, most slugs have two pairs of 'feelers' or tentacles on their head. The upper pair senses light while the lower pair is their sense of smell. When disturbed, they retract either pair, and if damaged, they can re-grow the tentacles. Slugs move through muscular contractions on the underside of their foot. Slugs feed on plant materials with a rasping, specialized mouthpart. Slugs can stretch their bodies to 20 times their normal length, allowing them to squeeze through the tiniest spaces to get to their food. They produce mucus to assist them with movement. The mucus secreted by their foot contains fibers to keep the slug from slipping down steep surfaces. Their bodies are made of mostly water, so their soft tissues need to always stay moist. A thicker mucus coats their entire body for protection from elements and predators. When attacked, slugs can contract their body, making their bodies more compact, which when combined with the slippery mucus, makes it difficult to grab. The mucus also is distasteful as a deterrent. For us, just touching this slime can be a deterrent!

The slime trail slugs leave behind has other effects than just assisting with transportation. A slug can use its own trail again and again to find its way around. Other slugs recognize the trail as their own species, leading to success in finding a mate. The trails can also be used by other slugs to find a good plant food source. Carnivorous slugs will also use the trails to find other slugs as a meal. Finally, many slugs will secrete slime cords to lower themselves to the ground.

Slugs feed mostly at night, seeking shelter during the day in soil or under leafy debris. They become more inactive during dry, hot weather, and more active after rain because of the moisture. In drier conditions, they hide in damp places such as under leaves, tree bark, logs, rocks, and man-made structures to retain their body moisture.

Fall is a great time for slugs. This time of year they lay up to fifty eggs in the soil, where the eggs will wait through winter or sometimes for years until moisture conditions are right. Their egg clusters look like colorless jelly. During the winter, some slug species overwinter in hibernation under ground while with other species, the adults die in the autumn.

To some gardeners slugs are considered to be pests because of the destruction they can create in our gardens. However, many slug species play an important role in our ecosystem by eating decaying plant matter. Some slugs eat other slugs and snails, earthworms, or even carrion. They are also food to snakes, salamanders, turtles, birds, toads and even humans. Explore your own back yard, as you never know what slime trails you might run into!

For over 42 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs. Post your own stories on the Nature Watch blog at cablemuseumnaturewatch.blogspot.com.

Saturday, October 9, 2010

Fall Color Pigmentation

Nature Watch
By Susan Thurn,
Cable Natural History Museum

As we go through another peak season of autumn colors, the mornings begin with a blaze of color as the sun shines on the leaves, and the night’s silence brings comfort and solace. The colors this year were golden! But just what do all those colors do?

First we have the magical chlorophyll, the special ingredient that converts sunlight into sugars. Chlorophyll absorbs red and blue parts of the light spectrum, so it reflects to our eyes as green. Just as sunlight can fade our fabrics colors, or damage our skin, sunlight also causes chlorophyll to break down. Green plants continually create new chlorophyll throughout the warm summer. Fall’s cooler temperatures slow down chlorophyll production, which is when leaves begin showing other colors than green.

The orange color we have seen so much of this fall season is the same color of many fruits and vegetables such as tomatoes, carrots, sweet potatoes, marigolds, pumpkins and even egg yolks and butter. These orange pigments are called carotene. In our bodies, carotene is essential for normal vision, for healthy skin and organs. It is believed to have protective properties against some types of cancer, and against ultraviolet rays of the sun. In plants, carotene absorbs sunlight energy, but instead of photosynthesizing like chlorophyll, it just passes the energy on to the chlorophyll. Carotenes are not damaged as easily by sunlight, so when chlorophyll disappears from the leaves in the fall, the carotene color is left behind for a longer time.

Finally, there are the anthocyanins, which show red and purple colors. These pigments are formed when plant proteins interact with sugars inside the plants cells. The colors formed are based on their acid levels. If the sap in the cells is acidic, the red colors will be brighter, and if less acidic, the color will show more purple. Anthocyanins do not play a part in photosynthesis, so there is some debate over what their purpose is in the leaves. Some believe that they provide a sunscreen for the leaves, allowing the leaves to reabsorb nutrients before they drop to the ground. Anthocyanins are also water-soluble, so can change the freezing point in the leaves, and so may protect a plant’s water supply. Blueberries and so many other fruits and vegetables are filled with anthocyanins, and also have healing powers. Whatever their role, they bring beauty to the colored autumn horizon.

Such a treat another fall has brought us. It brings joy to our eyes, and the rustle of the drying leaves brings a different music to our ears. Additionally, they can bring a variety of colors in our yard, gardens, and kitchens! Enjoy the benefits of these pigments in our foods, and enjoy the wonder of the seasons from our own back yards!

For over 42 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County

Wednesday, September 29, 2010

Chipmunks

Nature Watch
By Susan Thurn,
Cable Natural History Museum
Walking down the sidewalk, I heard a rustle in the undergrowth of the flower garden. I smiled when out zipped one of the chipmunk family living in the yard. Its puffy cheeks looked almost as big as its body as it crossed my path and scurried down into its tiny hole. These lively critters pudgy cheeks, stripes, and bushy tails have made them famous even in Hollywood, and for good reason.
Chipmunks eat a variety of foods including seeds, nuts, fruit, berries, fungi, insects, worms, bird eggs and nestlings, small frogs and sometimes even small mice. They gather food in areas where they can hide from their predators, and then store their food into their cheek pouches to carry to their burrow. This mammal’s scientific genus name is appropriate - Tamias, which in Greek means "storer," a behavior that this animal does so well as they collect and store food for a “long winter’s night.” Chipmunks can climb trees to harvest acorns or hazelnuts, but prefer foraging on the ground. They often spend sunrise to sunset searching for and storing food, harvesting as much as a bushel of nuts in just a few days. In August, chipmunks begin stockpiling these tasty treats in their burrows in preparation of winter. Chipmunks hibernate, but instead of storing fat like bears, they occasionally feed on their cache of nuts and seeds.

Chipmunks dig burrows with entrance holes about two inches in diameter and more than thirty feet in length. The main entrance can be found near stump or rocks, well-concealed from predators. Additional secondary entrances can exist in open areas, all part of an interconnecting underground system. The passages are two or three feet below ground. Their sleeping quarters are filled with shredded leaves and kept extremely clean. Food storage areas are in the lower tunnels to keep “refrigerated,” and leftover food shells and feces are stored in refuse tunnels. Now that is a well-planned home!
Chipmunks are important in a forest ecosystem. Their harvesting and caching activities help re-seed plants. They distribute spores of different fungi as well. They also can bring enjoyment into our lives. I know many Museum friends who enjoy chipmunks at their feeders, watch them run over their toes, and even name the often friendly creatures. Please share your own chipmunk stories at the Museum’s Nature Watch blog, at cablemuseumnaturewatch.blogspot.com.
For over 42 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs. Post your own stories on the Nature Watch blog at cablemuseumnaturewatch.blogspot.com.

Wednesday, September 22, 2010

Mushrooms

Nature Watch
By Susan Thurn,
Cable Natural History Museum

Our recent rain has been a mushroom lover’s delight. With so little rain the past few years, mushrooms seemed almost scarce in comparison. Now, when we walk through the woods we are greeted with a rainbow of colors, shapes, and sizes of amazing mushrooms. Of course they are of interest for their delectable tastes, and receive attention because of their additional ability to make those that eat the wrong mushroom extremely ill! Maybe we are more accustomed to noticing them when they are on our plate, or growing in our refrigerators. Still, they are worth our attention as we explore outdoors.

Mushrooms belong to the fungi kingdom. They cannot photosynthesize so must feed mostly on organic material. Their amazing success in reproduction is through spores, which is one reason we can find them almost anywhere. They are made up of microscopic root-like threads called hyphae. Their cell walls are made of chitin, the same material making up the shell of a crab, lobster, or dragonfly. Unlike humans who ingest their food and then digest it, a fungus digests its food first with the use of exoenzymes and then digests it with their hyphae. Because they do not need light for photosynthesis, they can live in any dark habitat, and grow in any direction. Their fruiting body used for reproduction is what we call mushrooms. Some scientists believe that molecular evidence leads to fungus being more closely related to animals then plants!

Because fungi feed on organic material, they are important in recycling nitrogen, carbon, and other nutrients. Some fungi are parasitic, feeding off of living materials and harming them in some way. Others live in beneficial relationships. Mycorrizae assist their host plants by helping the plant to capture water and elements from the soil such as zinc, phosphorus, and manganese, transferring them into the plant's roots. This fungi also protects trees against attack from pathogens. In return, the fungal partner receives from its host plant the vitamins, carbohydrates, and amino acids essential for its growth.

Fungi are much more than just the mold growing on our foods. They can break down almost every manufactured good except for some pesticides and plastics. They have been found to play a role in protecting plants in soils with high metal concentrations. They make fabulous bread and many other food products, including cheese. They are critical in antibiotics, steroids, and hormones. They even are the citric acid in our Cola! Finally, there are 250 species that are sought after food from the forest, while at the same time around the same number can be deadly or make you wish you were dead if you eat them. Mushrooms are certainly a part of our natural world that are “fun-guys” to have around.

For over 42 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs. Post your own stories on the Nature Watch blog at cablemuseumnaturewatch.blogspot.com.

Tuesday, September 14, 2010

Fall Phenology

By Susan Thurn,
CNHM Director of Education

What good is phenology? For some, it’s a year-round hobby that helps keep them in touch with the ebb and flow of the natural world. But the practice of noting and recording seasonal changes in nature does have what some would call more practical values.

For example, phenology is used to help with the prediction of insect emergence and strategies for insect control. Farmers, of course, are phenologists, and carefully correlate natural patterns and seasonal changes with crop planting and harvesting. Scientists who study global climate change trends pay close attention to the history of phenological data.

This time of year, the most obvious seasonal change is literally right in front of our eyes, as we are nearing the peak of leaf color change among our deciduous trees. The appearance of the beautiful yellows, reds, oranges we see is actually a result of the fading of the leaf’s green color, which is caused by cholorophyll. When chlorophyll fades, “beneath” it are other types of pigments that become revealed. These are the carotenoids, which produce yellow, orange, and brown colors; and the anthocyanins, which produce red, purple, and crimson colors.

The vibrancy of fall color is related to weather conditions that occur before and during the time when chlorophyll in the leaves is dwindling. A series of warm, sunny days and cool, crisp, but not freezing nights seems to bring about the most spectacular color displays.

The timing of the color change also varies by species. For example, oaks show their colors long after other species have already dropped their leaves. The differences in timing among species seems to be genetic, for a particular species at the same latitude will show the same coloration in high elevations at about the same time as it does in warmer lowlands.

Unique among the color-changing trees is the tamarack, also known as the eastern larch. In the spring and summer the tamarack has bright green flat, soft, and flexible needles. They are shaped uniquely on the branch in a whirled cluster somewhat like a flower’s petals. The trees are easy to identify by their narrow pyramid shape and their location—they’re most common in swamp and bog areas. This tree is both coniferous (produces cones) and deciduous (loses its leaves). Although the tamarack looks like an evergreen, it is not ever-green, because its needles change to a golden-yellow color in the fall and drop off.

About this time, northern flying squirrels begin visiting oak trees to feed on acorns. As the acorns mature you might find partly chewed ones on the ground. The squirrels feed at night, so if you want to see them, look for the acorns then keep your eyes open for squirrels scrambling up the trees.

Become a phenologist! Take a fall hike and note all the different colors of the forest. Gather wild apples and make your own applesauce or cider. Soak up the fleeting warmth of sunny fall days as we turn our thoughts to colder weather.

For over 40 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs. Post your own stories on the Nature Watch blog at cablemuseumnaturewatch.blogspot.com.

Tuesday, September 7, 2010

Moths

An email from a Museum friend recently stated, “I was talking with a neighbor/friend of mine tonight about this weird bird/bug I saw in my hanging flower baskets last night. Further research proved it to be a white-lined sphinx moth! It looked so much like a hummingbird, but yet not...I just had to find out what it was.” Late summer often brings this sphinx moth around our flowers, and it can often be mistaken for a hummingbird. Another species that has similar characteristics is the hummingbird moth. Both are beautiful insects to be enjoyed this time of year as they flutter furiously about our flower gardens.

The white-lined sphinx moth has white streaks along its upper forewing and body, from which it gets its name. Adults fly mostly at dusk and dawn, but also sometimes during the day. Their wingspan can be as much as five inches, and with their rapidly beating wings, on a quick glance can be confused with hummingbirds. They feed on a large variety of flower nectar including fuchsia, bouncing bet, evening primrose, petunias and thistles.

The second hummingbird mimic is the hummingbird moth. It is much smaller than the white-lined sphinx moth, with an olive to yellow body coloring, red bands across the abdomen, and mostly clear wings. Their body really seems to mimic similar coloring as the hummingbird. These moths fly during the day, hovering at flowers as they sip nectar. Adults prefer a wide variety of flower nectar including bee balm, phlox, vetch, and thistles.

Both of these “hummingbird moths” are to be thanked for their contributions as pollinators. The caterpillars of both species are also very interesting to find and observe. It is worth some time waiting and watching for these two moth species as they travel into your own back yards.

For over 40 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs. Post your own stories on the Nature Watch blog at cablemuseumnaturewatch.blogspot.com.

Monday, August 30, 2010

Red-Tailed Hawks

By Susan Thurn,
CNHM Director of Education

This was the week of the red-tailed hawk for me, as not only did I see them in flight, but I actually held one in my hands. The bird I held was a bird that can no longer live in the wild due to a dislocated shoulder. Just seeing this bird inspired awe inside of me. We often see red-tailed hawks soaring above open fields, circling while looking for their prey. Other times we may see them perched on a telephone pole. I would also guess that we all have heard the call of a red-tailed hawk, as Hollywood seems to have chosen the red-tailed hawk as the call on almost every movie!

Holding this red-tailed hawk in my arms was most amazing. The glove that protected my arm and provided the perch for the hawk just highlighted the amazing yellow coloring of their feet. Although it is one of the largest hawks in the United States, about 22 inches high and with a wingspan up to 52 inches, it only weighs about three pounds. The colors included a darker brown back, with paler brown below, a streaked chest, and a dark bar between its shoulder and wrist as seen from underneath. The red tail for which it is named is brick-red above and pinker below.

Red-tailed hawks will eat a variety of mammals that includes mice, voles, shrews, rabbits, snakes, and squirrels. They are capable of eating prey up to five pounds in weight. Red-tailed hawks have been observed hunting as pairs, each taking a side of a tree while trying to catch squirrels.

Very territorial, red-tailed hawks will aggressively pursue other hawks, eagles, or great-horned owls. Other behavior includes an elaborate courtship ritual in which the pair locks their talons together while in flight, spiraling down toward the ground before letting go. Their flight is a soaring, shallow v-shape called a dihedral, with very little wing flapping as they conserve energy. They occasionally hover above the ground while steadily beating their wings.

I was most impressed with the red-tailed hawk eyesight as this bird watched me like a hawk, responding to my every movement. Indeed their eyesight is thought to be 8 times better than that of a human. A red-tailed hawk can see a tiny mouse while flying 100 feet in the air! That is impressive, and makes it worth exploring red-tailed hawks from our own back yards.

For over 40 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs. Post your own stories on the Nature Watch blog at cablemuseumnaturewatch.blogspot.com.

Monday, August 23, 2010

No-See-Ums

By Susan Thurn,
CNHM Director of Education

“Ouch!” I exclaim. I look down to my arm ready to swat the mosquito I am sure just bit me. Yet nothing is there. Moments later, the itch begins, and the welt soon after is at least penny sized. These are the no-see-ums, a tiny biting fly that I hate to love. Aptly named, no-see-ums are less than ¼ inch long, a little black dots the size of a period that is very difficult to see. Boy, do we feel them though!
No-see-ums often stay in shrubs or the dead leaf litter across the ground. Just walking along can stir them up. They stay close to home, though, usually not flying more than about 350 feet from their breeding area. These flies, or midges, are just like many of the other flies or mosquitoes. They are active mostly at dawn and dusk. Only the females bite us. They need the protein in our blood to make their eggs. Yet how does such a small creature do this much “damage”? No-see-ums and other flies puncture the skin with mouthparts that look like scissor blades. Their tube-like mouth is called a proboscis, and is made up of several different parts. At the end of this mouth they have receptors to sense where to begin feeding. A pair of mandibles (the scissors) cuts the skin back and forth. Another part with backward facing teeth helps to move their mouth into their prey’s body. They then inject an anticoagulant saliva into our bodies, and finally begin to draw in blood from a blood vessel. These tiny creatures feed on mammals, birds, or reptiles. Males feed on nectar.

The no-see-um larvae hatch from eggs in water, mud, or moist leaf litter. The larvae eat dead plant or animal matter. During this part of their life cycle the larvae have a spiny “tail” that entomologists use to identify them. As adults, they have two wings with dense hairs that have special pigmentation that also allows biologists to identify them.

The reaction my body has is an allergic reaction to the proteins in no-see-um saliva. Thank goodness, for me, the itching subsides in a short time. In spite of my discomfort, these small insects do provide food to other creatures, making them just as important in the food chain. In tropical forests there is one species of biting midge that helps to pollinate chocolate, which helps in my mind to negate the irritation I sometimes have at their bites. Everything has its place, after all! For chocolate alone, perhaps it is worth loving them!

For over 40 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs. Post your own stories on the Nature Watch blog at cablemuseumnaturewatch.blogspot.com.

Monday, August 16, 2010

Where Have all the Monarchs Gone?

By Susan Thurn,
CNHM Director of Education

Where have all the monarchs gone? Several Museum members have mentioned their concern that they have not been observing monarchs much this summer. Even my own searches have yielded only three caterpillars this entire season. I’ve seen only four or five adults. It is a dismal showing for one of my long-time favorite butterflies.

As adults, monarch butterflies are migratory creatures. They travel great distances each fall to spend winter in temperate climates. Despite the fact that the range of the Monarch’s summer home is quite expansive, the wintering grounds are very limited. Some of these butterflies travel more than 2,900 kilometers to spend winter in places such as Michoacan, Mexico. In the spring, they begin the migration north, lay their eggs, and it is their children that finish the migration to northern Wisconsin. This inter-generational migration is an amazing phenomenon. So why are the numbers of monarchs lower?

In 2002 and 2004, freezing weather in Mexico followed by heavy rains wiped out huge numbers of monarchs during those years, creating a decline in the population. Spring of 2009 brought hotter than normal conditions for monarchs migrating north again, which was followed by the one of the coldest summers since 1928 in much of the breeding area, and finally, poor conditions during the fall migration, resulting in a very small overwintering population This past February, severe hailstorms followed by 15 inches of rain in Mexico are thought to have destroyed as much as 50% of the already declining population.

Added to this problem is the ongoing issue of habitat destruction in the world of monarchs. With an increased use of genetically engineered crops to become herbicide resistant, it has become easier for farmers to spray weed killer, killing any weeds and surviving milkweed while not hurting the crops. Monarchs are also under threat in Mexico due to illegal logging at their overwintering sites.

Scientists believe it will take two or more years for the monarch population to bounce back. Even then, there are still these human factors nature provides that could be a danger to the future of monarchs. Conservation groups are encouraging us all to improve monarch habitats by planting milkweed in our gardens at home, and to encourage schools, farmers, or others with unused land to grow these beautiful perennials. Perhaps with these efforts we can continue to explore and wonder at monarchs from our own back yards.

For over 40 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs. Post your own stories on the Nature Watch blog at cablemuseumnaturewatch.blogspot.com.

Monday, August 9, 2010

Northern Flickers

By Susan Thurn,
CNHM Director of Education

A whole host of flickers darted away from my vehicle as I drove down the road. The white rump and yellow tail feathers always make me smile. It is early August every year that the phenomenon occurs in which we observe flickers flying away from our vehicles as they leave the roadsides. It is perhaps a surprise to find a woodpecker being scared up from the ground rather than the trees, but northern flickers eat ants and beetles, digging for them with their unusual, slightly curved bill.

The northern flickers are foraging along roadsides mostly for ants. This bird species eats more ants than any other bird species in North America. Their long, barbed tongue laps up the insects off the ground. They hammer at the soil the same way other woodpeckers hammer into wood. By going underground they can eat the nutritious ant larvae as well. They also will eat flies, moths and butterflies, and in winter they add fruits and seeds to their diet.

Northern flickers have several interesting behaviors. The reason we see so many northern flickers this time of year is they are one of the few woodpeckers that migrate south for the winter. Also, unlike other woodpeckers, when flushed from the ground, flickers will choose thin horizontal branches to perch upon rather than tree trunks.

Northern flickers know their numbers. In spring and summer, rivals for a mate sometimes participate in a “fencing duel,” pointing their beaks up, bobbing their heads, and drawing a figure eight pattern in the air while calling their repeated “wicka” calls – all while the ladies look on.

Finally, flickers are known for their behavior called “anting” in which flickers allow ants to crawl up on their wings. There are different theories as to why this happens: one is that the ants’ formic acid is used as a fungicide or insecticide against feather or skin parasites or fungus. Another speculation is that anting is a comfort activity that stimulates the skin during a summer molt.

There are over 100 names for the northern flicker, including yellowhammer, gaffer woodpecker, wake-up, wick-up, and gawker bird. Not only do they have some fun names, but flickers are entertaining birds to watch. When we hear a drumming on a metal section of our house, it is often a flicker. When we see a feather on the ground with a yellow shaft, it is a flicker. How lucky we are to enjoy this bird species so often! Explore and wonder from your own back yard.

For over 40 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Also find us on the web at www.cablemuseum.org to learn more about our exhibits and programs. Post your own stories on the Nature Watch blog at cablemuseumnaturewatch.blogspot.com.

Tuesday, August 3, 2010

Turkey Vultures

By Susan Thurn,
CNHM Director of Education

A dark silhouette was flying over the field, recognizable by its dark profile and v-shaped wings. It was circling, two days in a row near my home. I smiled when I recognized a turkey vulture. Was it circling for some carrion? Or riding the winds? Some may refer to this bird as ugly, but I think it is beautiful, and turkey vultures have behaviors and adaptations that make them extremely interesting.
The turkey vulture got its name from the common turkey because of the similarities to the turkey’s reddish, featherless head. This almost bald head covered with a fuzz of down serves an important purpose. The turkey vulture eats dead carrion, and must stick its head inside the carcass to reach the meat, so the lack of feathers keeps the bird clean of blood and bacteria.

The turkey vulture does not feed strictly on carrion. They will also eat plants, including shoreline vegetation and some crops. They will soar above the ground searching for their food with their sharp eyesight and very developed sense of smell. They are not aggressive, and will not feed on live prey. Sometimes we can see them along roadsides looking for roadkill.

Turkey vultures are one of the few birds that have a heightened sense of smell, and the part of their brain that processes smells is very large. This raised awareness allows them to detect odors of dead animals below the forest canopy.

Do vultures circle the air looking for carrion? Actually, turkey vultures soar on warm bubbles of air called thermals. As warm air rises, they glide in circles to conserve their energy. They also use the thermals to raise higher so they can fly longer distances. Flying in circles also serves the purpose of letting them scan for food. Vultures are easily distinguished as they maintain a v-shaped flight, teetering side to side, to keep stability at low altitudes. Flying lower to the ground in this shape allows them to pick up the scent of dead animals. This flight pattern is quite a remarkable skill in the bird world, allowing vultures to glide for up to six hours without flapping their wings, diving out of the thermals at almost 60 miles per hour.

Turkey vultures are related to storks rather than birds of prey, and so they urinate on their own legs, using evaporation of water in the waste to help them cool down. It is also believed that the urine is acidic, helping to kill bacteria they may get from stepping in their own dead food. Vultures also have weak, chicken-like feet, which allow them to step on the ground and hold their food in place, rather than like other raptors that clutch their talons and fly in the air with their prey.
There are some additional adaptations that turkey vultures have. They roost in large groups except when they forage independently. They often can be seen with their wings wide spread, called the “horaltic pose,” perhaps to dry their wings, warm their dark body in the sun, or bake off any bacteria. Although they do not have many predators, their defense is to vomit. They cough up a lump of partially digested food, and the smell deters predators, or if it gets in their eyes, stings. Sometimes, they will vomit a large amount of “meal,” which predators may choose to eat instead of pursuing the vulture.

Keep your eyes out for turkey vultures in the air nearby. They will begin migrating later in September, so will become even more visible. Who knows what you might see happen! Explore and wonder from your own back yard.


Nature Watch is brought to you by the Cable Natural History Museum. For 40 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M or on the web at www.cablemuseum.org to learn more about exhibits and programs.

Tuesday, July 27, 2010

The Lost Ladybug

By Susan Thurn,
CNHM Director of Education

This week’s Museum Junior Naturalists went out in search of ladybugs. Ladybird beetles, to be precise. This adventure was part of a citizen science project for the Lost Ladybug Project, a search for native ladybugs organized by the Cornell University Department of Entomology. Twenty-six children ages 5-12 donned their insect nets in a field and forest edge along the Namekagon River. We swept above the flowers and plants with hopes of finding ladybugs. We placed a sheet underneath tree branches and gently knocked the branches to observe what fell out of the trees. After a thorough search, we successfully caught ONE ladybug, which promptly flew away. I had thought that an adventurous group of children would be the perfect eyes to spot a ladybug. Now I wonder if they even really knew what they were looking for. Do they, like I did as a child, play regularly with ladybugs?

How could it be that we could only find one ladybug? Three ladybug species, the two-spot, the nine-spot, and the transverse ladybugs were once common but now appear to be rare. Three other species, the parenthesis, spotted pink, and convergent ladybugs, are more common natives. Scientists believe these native ladybugs are disappearing, and the Lost Ladybug Project is using citizen-based science to help find them. Scientists are looking for information on which ladybugs are still present and how many individuals can be found.

While many of the natives seem to be disappearing, ladybugs from other places have greatly increased their numbers and range. Many of us are familiar with the multicolored Asian ladybug, introduced from Japan for biological control of insects. This ladybug has a big appetite, and has adapted to eat the same foods our native ladybugs eat, even eating native and its own ladybug larvae. This is the same ladybug we see in our homes as they winter in huge masses. The checkerspot and seven-spotted ladybug are also ladybugs that were introduced into North America in the late 50’s and 60’s, and their populations continue to spread.

What are the current results of the Lost Ladybug studies? According to the ladybugs being reported, the numbers of introduced ladybugs far exceeds that of the natives. Over half of the findings are introduced ladybug species. Scientists are discovering which habitat niches in which the native ladybugs are the most successful. They are finding that the Asian ladybug is spreading its range into places that wasn’t previously inhabited. Pathogens are being found in native ladybug populations which could be contributing to their decline. Research is showing that native ladybugs that have less food grow into smaller, shrinking adults. Finally, evidence is appearing that the native nine-spot is inter-breeding with the introduced seven-spot ladybug.

Why should we care about ladybugs? They are beautiful. I remember as a child of seven, loving them, catching them again and again and enjoying their tickles across my skin. I learned from a ladybug about how animals use their bright coloring as a warning to predators to remind them of the awful repellents they release when attacked. They are very important because they assist with eating other plant-feeding insects, keeping those populations low. The fewer the ladybugs, the more fragile ecosystems can become during a pest insect population explosion. Keep your eyes open for a ladybug in your own yard. Share your ladybug stories at the Museum’s Nature Watch blog at www.cablemuseumnaturewatch.blogspot.com. Explore and wonder from your own back yard.

Nature Watch is brought to you by the Cable Natural History Museum. For 40 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M or on the web at www.cablemuseum.org to learn more about exhibits and programs.

Monday, July 19, 2010

Night Sky

By Susan Thurn,
CNHM Director of Education

The “dog days” of summer are here! We refer to them as the hottest days of the year. These dog days are based on an ancient Greek belief that Sirius, also called the Dog Star, was responsible for the heat. Skywatchers of long ago actually thought that the heat from Sirius and the sun combined to produce hotter weather. Ancient Egyptians used the star as a “watchdog,” as Sirius appeared in the night sky right before the Nile River’s flooding season. There are several interesting events to watch for in the next week in the night sky as we enter this year’s dog days.

Right after sunset, be sure to check out the low western horizon to see the planets lined up, from left to right, Saturn, Mars, and Venus. Venus is so bright it is the second brightest object in the sky (next to the moon,) so look there first. Mars and Saturn are next to it, but they might be fainter. Each night, they seem to be getting closer and closer together, which is a line of sight effect, but still a fun race to watch in the night sky. A glimpse of Mercury can also be made down very low in the skyline, but a pair of binoculars might help to view it.

There are exciting stars and constellations to look for in our night sky. Look south in the night sky for a bright orange star called Antares that helps to identify the hook-shaped Scorpius, while just to the left, the brightest stars of Sagittarius form a teapot. The steam above the teapot’s spout is the Milky Way. Look in the eastern sky for the summer triangle. The brightest star shining in that direction is Vega. Deneb is the star on the lower left corner of the triangle and Altair is on its lower right.

The last night sky treats to watch for include the July 26 full moon, and the southern Delta Aquarids meteor shower peak that will occur July 28-29, producing 20 meteors per hour at their best. The best viewing of this meteor shower is in the east, after midnight, in the constellation Aquarius. Jupiter also begins rising in the east between 11:00 p.m. and midnight, and for those who are early risers, the brightest object in the southeast before dawn, is Jupiter.

Turn out the night lights in your home, and get outdoors with a telescope, binoculars, and a chair or blanket. Explore and wonder from your own back yard.

Nature Watch is brought to you by the Cable Natural History Museum. For 40 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M or on the web at www.cablemuseum.org to learn more about exhibits and programs.

Tuesday, July 13, 2010

Woodland Butterflies

Woodland Delights

Susan Thurn,
CNHM Director of Education

My mother is a passionate gardener, and she knows all of her plant friends by name. Others have birds at their feeder, or squirrels, chipmunks, or bears that they know and call by name. A Museum member called to report her repeated observation of Compton’s tortoiseshell butterflies this week. The following day, I was out scouting Mount Telemark for a hike up the big hill, and saw a variety of woodland butterflies as well. In northern Wisconsin, we have several woodland butterflies that are worth getting to know by name. Please let me introduce you to the Compton tortoiseshell, northern pearly-eye, common wood nymph, and little wood-satyr, all woodland delights.

The Compton tortoiseshell butterfly is more common in our northern counties. It belongs in a group of butterflies called true brush-foots because they appear to have only four legs. Their front forelegs are reduced in size, usually hairy and resembling brushes. Adults emerge in July, in deciduous woodlands, trails, openings, and woodland edges. From above, this butterfly looks mostly a rusty orange and black butterfly, with single white marks near the edge of each wing. The wings have sharper angles with a small tail on the hind or lower wing. From below, the butterfly could be mistaken for tree bark, as they have a camouflaged coloring with a silvery mark in the middle of the hind wing. Last year, Compton’s tortoiseshell butterflies were seen in higher numbers, as the species does have periodic fluctuations in its populations, being abundant for years and then disappearing for other years. Its common name is from a famous English naturalist, Philip Gosse, who studied the butterfly while living in the town of Compton in Quebec in the nineteenth century. These butterflies overwinter as an adult, mating in the spring for a July emergence.

The northern pearly-eye butterfly is a common woodland species rarely found in openings. It is also commonly seen in woodlands, woodland edges, or while we are hiking down a woodland trail. This species is best identified by its brown coloring with lighter areas on the fore or front wing, and two obvious dark spots through both wings. Other spots trail down the hind wing. From below, the spots are circled with a yellow, brown, and white ring. The hind wing spots have a small white dot in the center. This species may be more difficult to identify with its fast, erratic flight that sometime ends further away against a sunlit tree.

The common wood nymph may be the most common butterfly in Wisconsin in a woodland habitat. Its lack of color makes it less conspicuous, but still worth looking for. This species is usually seen from below, so its underside has two large eyespots with a yellow ring on its fore wing. It is most often found in open fields near woodlands. This is the most common satyr butterfly that can be seen, and the best time to catch a flash of this butterfly is in July.

The less common little wood-satyr is often mistaken for a northern pearly-eye, but the little wood is much smaller, and found flying within only a few feet of the ground. They also fly more slowly, looking almost lazy in its flight. From above, it has two obvious eyespots on the fore wing and on the hind wing, ringed with white. When seen from below, it has two eyespots on the fore wing, while the hind wing has two eyespots and several smaller eyespots. There are also two darker lines across both wings. This species is also found earlier in the season, more in June than July.

My passion in nature is for butterflies. I try to know all their names, and take great joy in learning more about them through observation. These four butterfly species are all so amazingly camouflaged that I find it difficult sometimes to identify them. I use little things to help me remember them: Compton’s – orange and black with white; pearly-eyed – two main spots, trailing spots, with white dots in the center; common wood nymph – obvious large eyespots on the forewing with yellow rings; little wood satyr – smaller with two spots on top (forewing) and two on bottom, and lazy flight near the ground. May you all get to know these butterflies, and enjoy these woodland delights!

Nature Watch is brought to you by the Cable Natural History Museum. For 40 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M or on the web at www.cablemuseum.org to learn more about exhibits and programs.

Tuesday, July 6, 2010

Eggs in a Basket

Susan Thurn,
CNHM Director of Education

The Eastern phoebe is nesting in the same nest again in my house eaves. Not just for the second year, but for the second time this year. Many bird species have more than one brood in a season. Birds may lay more than one brood per year as a survival strategy. A bird is driven to pass on its genetic material through reproduction, and more young can mean more of them reach adulthood. Many songbirds have enough time to raise more than one family with a short period of time between egg-laying and fledge time. Their young can still have time enough to fatten up for their southern migration, or to prepare for our northern winters. It used to be thought that most birds nested for life. However, some birds do not nest for life, and some birds do not even keep the same mate for a second brood. How many eggs does a bird “put in a basket,” anyway?

Eastern phoebes are very loyal to their nesting locations, using them not only for their typical two broods per season, but also using them for many years. The phoebe makes repairs to the nest, apparently following the 3-R’s – reduce, reuse, recycle, by using the nest again. Most research suggests that phoebes keep the same mate through the season. Other birds in our region that can have two broods per season with the same mate include chipping, field, and song sparrows, juncos, towhees, catbirds, and robins.

Birds that often have two broods per season and sometimes choose different mates for the second brood include brown thrashers, bluebirds, and house wrens. The story gets even more interesting, however. Bluebird studies have shown that generally, northern birds have fewer broods than southern birds, but still have about the same number of young each season. In our neck of the woods (or fields, as that is the habitat bluebirds prefer,) bluebirds have two broods. Further south, where the food supply of insects is greater because of a longer warm season, bluebirds have three broods. Broods in the north lay more eggs than bluebirds in the south, and so end up with about the same number of young.

Would it be better to have more babies at once, or spread them out over one season? Would there be an advantage to having more nests, but fewer mouths to feed? Do northern birds sacrifice time to raise and train fledglings? Perhaps only a parent could know. Actually, it appears that there is a trade-off because although southern birds might have a “basket” full of more eggs, they have higher hatching failures.

It is fascinating to continue discovering about the natural history and science of birds. It was a Museum member who brought this question about birds and their second broods to my attention. It is often this spark of curiosity that will lead us to our own discoveries, perhaps to a bird in our own neighborhood that is in the midst of its second brood.

Nature Watch is brought to you by the Cable Natural History Museum. For 40 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M or on the web at www.cablemuseum.org to learn more about exhibits and programs.

Monday, June 28, 2010

Weather Folklore

Susan Thurn,
CNHM Director of Education

“Wait a day and the weather will change.” Although a common saying in northern Wisconsin, it hasn’t been true lately. Although we have been the lucky recipients of some long-awaited, much-needed rain, cabin fever is setting in to my brain. Also, with several education programs at the Museum this past week, I’ve been looking upwards a lot to find out if we are doing outdoor or indoor explorations, I also have been interested in how to tell if it’s going to rain, and interested in how people can know this without going to the local television forecast, or the Doppler radar on the internet. People have been forecasting the weather for centuries. They have looked to plants and animals – are ants moving to higher ground, do the frogs croak more frequently, is a sheep’s’ wool uncurled? Are there signs we can use to tell us if it is soon going to rain?

First, I go to the Museum’s Naturalist, Cully Shelton, as he always seems to know when it’s going to rain in the next few minutes. Cully recently told me, “When the clouds seem so low you could touch them…when the clouds are touching the trees, then it’s likely that there is going to moisture precipitating out of them in a short length of time. Another favorite observation I use is when you see puffy, white cumulus clouds, which means that within a 12 hour period there should be rainfall.”
What about some of the folklore we all know? "When the glass is low on a ship, the sailors get ready for a storm,” or "When your joints hurt, a storm is coming," are common occurrences we often hear. Both of these folklore statements refer to low air pressure systems which do often mean storms are on their way.

"Red Sky at night, sailor's delight. Red sky in the morning, sailor take warning." It turns out there is some truth to this saying. When our western sky is clear, we often get a red sunset because as the sun sets, its light shines through the lower atmosphere containing more dust, smoke, or pollution. With these clear skies and high air pressure, the air sinks, causing the contaminants to be held closer to the earth surface. These particles scatter the shorter wavelengths of light, leaving longer wavelengths that create orange and red colors, creating the sky that brings weather delight to the sailor. If the sky is red in the morning eastern sky, the high pressure may have already passed, and a low pressure period may follow, usually bringing clouds, rain and storms.

Another favorite folklore statement is, "Mare's tails and mackerel scales make tall ships take in their sails." These mackerel fish scale looking clouds make reference to cirrocumulus clouds, and mare’s tails represent cirrus clouds. Both types of clouds can indicate a warm front that is approaching where two air masses meet, bringing changing winds and precipitation. This prediction of high winds would make it necessary for boats to reef their sails.

"When the stars begin to huddle, the earth will soon become a puddle" is another clue that can be used to forecast weather. As clouds increase, large areas of stars are hidden, while a burst of stars can seem to be huddled together in a section of clear sky. As this sign means the clouds are increasing, the chance of rain is definitely possible.

There are also some clues we can also learn from nature. Some flowers close up as humidity levels rise so their pollen doesn’t get washed away. Cicadas cannot vibrate their wings in high humidity, so can be silent with approaching rain. Swallows sometimes fly lower when there is dropping air pressure. Crows and geese have been known to call more frequently with falling air pressure. Flying insects are more active when air pressure is dropping, staying closer to the ground so that it might seem like they are swarming. With all of these clues, who needs a television or computer?

Nature Watch is brought to you by the Cable Natural History Museum. For 40 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M or on the web at www.cablemuseum.org to learn more about exhibits and programs.

Tuesday, June 22, 2010

Clean Air

Susan Thurn,
CNHM Director of Education

Breath Deep

Take a deep breath. And again. I just spent a week’s honeymoon in New York City, and I learned one incredibly important thing this past week. I love New York, but I love clean air even better. I learned how much I take our northern Wisconsin’s clean air for granted. The cultural and architectural sights, the Broadway shows, the food, and the 10 million working people of New York City were all amazing, but I missed the air of the north woods. I missed waking up and knowing the weather outside, sunny or cloudy, without having to try and figure it out through the smog. It was a fresh breath of air coming home again!

Air – we breathe and expose our lungs to about 35 pounds of it every day and 2 gallons every minute. This air is made up of gases – nitrogen, oxygen, argon and other natural ingredients. Smaller amounts other naturally occurring gases are found on earth such as water vapor, carbon dioxide, methane, nitrogen dioxide and sulfur dioxide. Tiny particles, bits of earth, sea salts, pollen, and microscopic microbes, are blown into the air. These substances play an important role in regulating and sustaining life on our planet.

According to a New York City Community Air Survey, wintertime air quality across the city, found results that Manhattan and the more developed, high-traffic locations in five of the studied boroughs have the city's highest particulate levels. The beautiful Manhattan skyline has certainly been changed by the smog and air particulates. This is just one part of our planet, however. According to the Environmental Protection Agency (EPA,) 50 million Americans live with ozone levels above the current national standard. Worldwide, 1.4 billion people breathe polluted air every day.

None of this information about our air is a surprise to us, and there is good news. According to EPA estimates, the Clean Air Act has helped significantly through a savings of $22 billion in health costs, material damage, and more. Here at home in northwestern Wisconsin, we have an air quality index that is marked as “Good.” In comparison to other places, perhaps it should be marked excellent.

In spite of this good news, my recent city experience was a strong reminder of what daily life could be like in other places. Wisconsin, like all other states and countries fights their battles with growing carbon dioxide emissions, ozone, mercury, and a host of other air quality issues. This past week brought about a renewed sense of commitment to decreasing my personal global footprint. Let us all be reminded of the air that we breathe daily and all take for granted. Let us stop what we are all doing for a moment, breathe, and appreciate what we take in every day, every moment of our north woods lives, and enjoy it!

Nature Watch is brought to you by the Cable Natural History Museum. For 40 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M or on the web at www.cablemuseum.org to learn more about exhibits and programs.

Monday, June 14, 2010

Turtle Crossing

Susan Thurn,
CNHM Director of Education

Beware! It’s turtle crossing time! Over the weekend, I was saddened to find a 20+ year-old snapping turtle dead on the side of the road. Phone call questions have also come into the Museum asking about turtles and how to cope with their change in lifestyle that impacts ours this time of year. Motorists are likely to see turtles crossing roads near lakes, rivers and wetlands right now because the roads separate the aquatic habitat, from the drier soils in upland habitats that female turtles prefer for egg-laying. Their nests also end up in our backyards and driveways, making for an exciting experience!

All Wisconsin turtles lay their eggs on land, usually in a nest that they dig. Painted turtles may nest twice in the same season, but other species only once. Most turtle species begin their nesting around dusk or dawn, although it can occur throughout the day. Snapping turtles can lay 30-80 eggs, while smaller turtles lay up to five eggs. Once the eggs are laid, the female departs, allowing the eggs to hatch on their own. There is great danger in making a roadside nest. The mortality from automobiles is significant because turtles are very slow to mature, taking up to 20 years to reach sexual maturity. This makes it important for motorists to drive with caution in wetland areas in order to protect our female turtles.

Although the danger is over once the female adult turtles have left the nest, the danger has just begun for the eggs. Turtle eggs can take 60-90 days to incubate, and so are often uncovered and eaten by predators such as raccoons, foxes, skunks and crows. With cooler summer temperatures incubation can take longer. Turtles that hatch in the fall overwinter in the nest, using a glycol/sugar antifreeze to keep the eggs or hatchlings from freezing. Summer temperatures actually determine the sex of many Wisconsin turtles. Blanding’s, painted, box, and snapping turtles produce more females at higher temperatures, while more males are produced at lower temperatures.

For those who might find a turtle who has laid eggs in their yards or driveways, and are looking for a way to protect the nest from their pets, or predators, resources suggest placing an object over the nest site such as a oven shelf or plastic egg crate that might prevent predators from digging to get the eggs. This past week’s rain might also help erase the scent that many turtles leave behind, making it more difficult for predators to smell the eggs.

Help a turtle by allowing them time to cross roads, while keeping safety in mind. Road mortality is especially significant for our rare and endangered Blanding’s and wood turtles. However, even our more common snappers or painted turtles can experience mortality rates that cause populations to decline and suffer. Almost half of Wisconsin’s turtles are experiencing declines. Giving turtles the time to move out of the way or occasionally using a stick to help them move to safety can truly help an animal that is a fascinating part of a diverse northern Wisconsin.

Nature Watch is brought to you by the Cable Natural History Museum. For 40 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M or on the web at www.cablemuseum.org to learn more about exhibits and programs.

Tuesday, June 8, 2010

Whip-Poor-Whil

Susan Thurn,
CNHM Director of Education

It is a bird I have never seen, but hear every night right now, just outside the windows of our house. The song goes on for what seems like forever. It is the sound of a whip-poor-whil, singing “whip-poor-will” with an accent on the first and last syllables. A famous naturalist, John Burroughs, once heard a whip-poor-will make 1,088 vocal repetitions before taking a break. Whip-poor-wills belong to a family of birds called nightjars because their loud songs "jar" the night. They are also called goatsuckers because of a superstition that the birds drink milk from farm livestock at night. The name whip-poor-will and that of many other nightjars is a fairly accurate description of what the bird sings.

The whip-poor-will song begins in the spring. During their courtship, the female will land near a calling male, who then will walk towards her with a fancy gait, head bobbing up and down. When he reaches her, he circles as she bobs, while both continue to sing their songs. He will also approach her from the side and touch her bill while she trembles. The nest is built on the ground on leaf litter in areas where there is little or no undercover. The birds time their egg-laying with the moon, synchronizing it so the usual two eggs hatch about ten days before the full moon. This timing allows the adults to forage all night for food with the greatest amount of moonlight. Both parents feed their young regurgitated food. The chicks hop along the ground very quickly after hatching, using their parents camouflage to hide them. If this fails, the young scatter and freeze while the adults distract the invaders. How unfortunate that we rarely get to observe any of these activities!
Hunting is obviously a part of the whip-poor-whil’s nocturnal lifestyle, and while an owl hunts mostly by sound, the whip-poor-will searches for its prey by sight. As a result, they are most active at twilight, dawn, and on brighter moonlit nights. They will catch insects, ranging from mosquitoes to moths, grasshoppers and beetles. In spite of a small bill, they can open their mouths wide when in flight, foraging while wheeling or circling, even hovering for their prey. They will also make short flights out from the ground or branches to catch prey. They use the silhouette of their prey against the night sky. Such creative strategies for hunting!

Legends of whip-poor-whils include a New England story that the bird can sense a soul departing, and can catch it as it flees. An American belief is that the singing of the birds is a death omen. Stephen King and other movie creators have used the song to help create suspense or other moods.

How can a human be lucky enough to spot a whip-poor-will? Their eyeshine reflects red at night, and sometimes they can be seen in a moth-like flight. The birds can sometimes be seen sitting on roads, with small, weak feet and short legs, as they hop about awkwardly. They usually sit lengthwise on their perch instead of other birds who sit across them. Perhaps someday I will be lucky enough to capture a visual moment of a whip-poor-will. Until then, I will enjoy, as do my neighbors, their nightly song.

Nature Watch is brought to you by the Cable Natural History Museum. For 40 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M or on the web at www.cablemuseum.org to learn more about exhibits and programs.

Wednesday, June 2, 2010

Nest Sanitation

By Susan Thurn,
CNHM Director of Education

A pair of tree swallows has built their nest in the Museum’s bluebird nesting box. The Eastern phoebe is back again on the same nest at my house. The bald eagle is back roosting on the same tree on the Namekagon River, not far from its nest. Imagine the fragility of a nest, which often forces birds to build a new nest every year. However, nests that overwinter can harbor deadly numbers of pathogens or parasites that await the returning birds. What do birds do to cope with these issues?

Nests are often alive with invertebrates that feed on birds, their waste, or on each other. Flies, ticks, mites, fleas, and ticks or bacteria and fungi are discouraged by many different strategies birds use.

One of the most widely used methods is to remove the fecal sacs of the young. Some materials are selected by the parenting birds that help to sanitize the nest. For example, some hawk species continually add fresh leaves that contain pesticides such as hydrocyanic acid, which impacts parasites. Starlings can discriminate between leaves and choose the best to deter lice or bacteria which they include in their nests. Cedar bark is also used for its repellent properties. Nuthatches rub pine pitch and insects around the entrance to their cavity, relying on the defensive chemicals of the pitch and insects to protect them. Some birds of prey’s young defecate outside of the nest or in other birds, outside their nest hole opening. Some bird species put carnivore scat in their nests to repel smaller predators. The great-crested flycatcher puts a snake skin into its nest, which is believed to deter predators such as squirrels.

Birds definitely go to great lengths to protect their young. If heavy parasitism or infestation of a nest begins, birds will desert the nest, and in some cases, entire bird colonies have moved themselves to a new site. It is amazing the ingenuity that the bird world uses to survive!

Nature Watch is brought to you by the Cable Natural History Museum. For 40 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 and new exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M or on the web at www.cablemuseum.org to learn more about exhibits and programs.