Nature Watch
By Susan Thurn,
Cable Natural History Museum
They have a seven-foot wingspan. They can fly average speeds of 30 miles per hour. They are amazing predators in the sky. They are incredibly beautiful. They are America’s symbol. They are the bald eagle, and they are something that most humans never tire of observing.
Saturday evening I was at a Cable community event, and several people asked if I’d seen the eagles near the Namekagon River on County Highway M. My family and I saw four of them, although others shared that they had seen ten earlier in the day. The excitement was shared by all of the observers.
Research has shown that bald eagles in the Great Lakes area don’t usually migrate. Our northern eagles fly far enough south to find open water with sufficient food supply. An eagle can travel up to 100 miles on a winter day to find food.
The week of March 22, 2011 brought a huge number of migrating eagles back along the Mississippi River, a place not too far away from us as the “crow” flies. The bald eagle can fly hundreds of miles in just a few days. They migrate in large groups, streaming along in a path that can be up to thirty miles long with over a half-mile width. Daylight is the cue to migrate rather than weather, so eagles can migrate north to their home range to find that winter is still present. Then they cope with food availability, often depending on road kill for their meals if open water is not an option.
Bubbles of rising, warmed air, called thermals, are what aids eagles in migration. They glide on these thermals in the desired direction until they find another. This method of flight allows them to conserve energy.
Eagles are diurnal (daytime) fliers, and probably use landmarks to guide them to a home territory, while using more specific cues to find their nest tree. Clearly their memories must be great, showing a high level of intelligence.
Immature bald eagles will often wander back to their birth territory in the spring, but do not always stay put. Usually around age five, when they reach sexual maturity, they will establish nesting sites within 300 miles of their birthplace.
Living among some of the greatest bald eagle habitat, we are fortunate to be able to see bald eagles almost daily. They are an integral part of our ecosystem, one that is worth taking great care of, here in 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 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. Also discover us on Facebook, or at our blogspot, http://cablemuseumnaturewatch.blogspot.com/ to learn more about our exhibits and programs.
Wednesday, March 30, 2011
Thursday, March 24, 2011
Spring Music
Nature Watch
By Susan Thurn,
Cable Natural History Museum
I couldn’t stop smiling this morning. I heard the familiar sound of a honk as I left my house for teaching today. I looked out across the field, and saw a Canada goose flying by the house. Its honk called to me, reminding me of migration and warm weather and spring!
Here are some fascinating facts of a very versatile bird:
The further north we live, the smaller the geese are. There are eleven subspecies of geese. One of the subspecies is named the cackling goose, and lives in the very northern parts of Canada.
Canada geese tend to choose a mate of a similar size. This is called assortative mating, which may help ensure better reproductive success. Pairs mate for life and remain together year long. During most of the year the geese stay together in large flocks that are often related to each other.
Every spring when the geese land in the field, I watch them circle, and then a small group peels off before landing. Around goes the remainder of the group in flight, while another group alights. When Canada geese migrate, they stay in these family groups, and it is these same family groups that land each time.
During our spring, geese feed mostly on grass and sedges, which allows them to do well in a variety of habitats. They also eat a more elusive plant, the skunk cabbage. Geese have become more successful due to agricultural practices, feeding on grains, as they are very adept at removing corn kernels from the cobs. Fall and winter is a time when they rely more on seeds, berries and grain. Their ability to eat crops and grass has opened up both rural and urban environments, decreasing their migratory habits and allowing them to stay in many areas year round.
When a flock of Canada geese get ready to take off in flight, they join together in the chorus of loud honks in which we are all so familiar. Geese also have loud calls when threatened or excited. In addition to their calls, geese apparently have a host of body moves that are worth observing when one gets a chance.
Spring has sprung. Take time out to enjoy the outdoors, listening to the easily identified honking as it spills down from the skies. Look for the “V” of migrating geese along the horizon. Acknowledge the hallmark of a new cycle of life. Enjoy these pleasures in our own north woods 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 exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Discover us on the web at www.cablemuseum.org, on Facebook, or at our blogspot, http://cablemuseumnaturewatch.blogspot.com to learn more about our exhibits.
By Susan Thurn,
Cable Natural History Museum
I couldn’t stop smiling this morning. I heard the familiar sound of a honk as I left my house for teaching today. I looked out across the field, and saw a Canada goose flying by the house. Its honk called to me, reminding me of migration and warm weather and spring!
Here are some fascinating facts of a very versatile bird:
The further north we live, the smaller the geese are. There are eleven subspecies of geese. One of the subspecies is named the cackling goose, and lives in the very northern parts of Canada.
Canada geese tend to choose a mate of a similar size. This is called assortative mating, which may help ensure better reproductive success. Pairs mate for life and remain together year long. During most of the year the geese stay together in large flocks that are often related to each other.
Every spring when the geese land in the field, I watch them circle, and then a small group peels off before landing. Around goes the remainder of the group in flight, while another group alights. When Canada geese migrate, they stay in these family groups, and it is these same family groups that land each time.
During our spring, geese feed mostly on grass and sedges, which allows them to do well in a variety of habitats. They also eat a more elusive plant, the skunk cabbage. Geese have become more successful due to agricultural practices, feeding on grains, as they are very adept at removing corn kernels from the cobs. Fall and winter is a time when they rely more on seeds, berries and grain. Their ability to eat crops and grass has opened up both rural and urban environments, decreasing their migratory habits and allowing them to stay in many areas year round.
When a flock of Canada geese get ready to take off in flight, they join together in the chorus of loud honks in which we are all so familiar. Geese also have loud calls when threatened or excited. In addition to their calls, geese apparently have a host of body moves that are worth observing when one gets a chance.
Spring has sprung. Take time out to enjoy the outdoors, listening to the easily identified honking as it spills down from the skies. Look for the “V” of migrating geese along the horizon. Acknowledge the hallmark of a new cycle of life. Enjoy these pleasures in our own north woods 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 exhibit, On Lake Owen: The Art of Walter Bohl, in Cable at 13470 County Highway M. Discover us on the web at www.cablemuseum.org, on Facebook, or at our blogspot, http://cablemuseumnaturewatch.blogspot.com to learn more about our exhibits.
Wednesday, March 16, 2011
Spring has Sprung
Nature Watch
By Susan Thurn,
Cable Natural History Museum
I had a headache today. It burned and made teaching fourth graders much more difficult. The headache wasn’t from the teaching, however. Nor was it from a cold that's been pestering me. It was a change in the weather that made it that way, a change in the barometer that makes my sinuses go mad. It was a sign of spring on its way that lifted my spirits in spite of the pain.
We are approaching the spring equinox, March 21, labeled one of the great solar celebrations of the year. It is the time in which day and night are nearly equal, and about to tip over to the light. Daylight will continue to lengthen, and is also just one of the precursors that spring is on its way. There are many other things in nature that will be happening now and in the next few weeks in which we can look for.
Right now, according to mom’s report from the feeder, the American goldfinch is returning to its bright, brilliant colors. As they lose their feathers, or molt, the goldfinch gains the yellow plumage in the male. The color is produced by carotenoid pigments such as beta-carotene that come from their spring plant diet, important when they are replacing their contour, colorful feathers.
Tree sap will begin to flow as our days get warmer. The sugar maples will become a source of future delight that we can taste from its syrup.
Chickadees also begin their spring mating call, which sounds more like a “fee-bee” sound than the typical “chick-a-dee-dee-dee” song we are used to hearing throughout the rest of the year.
Ruffed grouse begin their drumming that will continue into May. Male grouse begin declaring their “property rights,” or territory, by beating their wings against the air to make a thunderous drumming sound. The drummers stand on a log or mound as they beat their wings to protect their home range up to ten acres.
Large mixed flocks with male red-winged blackbirds will soon be migrating back. We’ll most likely hear them in trees or wetlands as they chatter with one of the first spring bird songs.
Woodcock also return for their spring courtship display that the male uses to attract females. The males begin their song and dance at sunset, in a field or clearing. He sings out, calling repeated “peents,” followed by an occasional bobbing of his head, a turn, and a repeat of the dance again while broadcasting his song in different directions. They then fly upward into the sky in a wide spiral, moving higher and higher. As he gets higher, the male’s wings whistle, creating a “twittering” sound. Finally they begin their descent downward, zig-zagging back and forth, down to the ground without a sound.
If spring fever has any of us in its grip, it is time to get outdoors! Walk, whether down the road or in your own forested back yard. There are many exciting signs that spring is on its way for us to see and enjoy!
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. Also discover us on the web at www.cablemuseum.org, on Facebook, or at our blogspot, http://cablemuseumnaturewatch.blogspot.com/ to learn more about our exhibits and programs.
By Susan Thurn,
Cable Natural History Museum
I had a headache today. It burned and made teaching fourth graders much more difficult. The headache wasn’t from the teaching, however. Nor was it from a cold that's been pestering me. It was a change in the weather that made it that way, a change in the barometer that makes my sinuses go mad. It was a sign of spring on its way that lifted my spirits in spite of the pain.
We are approaching the spring equinox, March 21, labeled one of the great solar celebrations of the year. It is the time in which day and night are nearly equal, and about to tip over to the light. Daylight will continue to lengthen, and is also just one of the precursors that spring is on its way. There are many other things in nature that will be happening now and in the next few weeks in which we can look for.
Right now, according to mom’s report from the feeder, the American goldfinch is returning to its bright, brilliant colors. As they lose their feathers, or molt, the goldfinch gains the yellow plumage in the male. The color is produced by carotenoid pigments such as beta-carotene that come from their spring plant diet, important when they are replacing their contour, colorful feathers.
Tree sap will begin to flow as our days get warmer. The sugar maples will become a source of future delight that we can taste from its syrup.
Chickadees also begin their spring mating call, which sounds more like a “fee-bee” sound than the typical “chick-a-dee-dee-dee” song we are used to hearing throughout the rest of the year.
Ruffed grouse begin their drumming that will continue into May. Male grouse begin declaring their “property rights,” or territory, by beating their wings against the air to make a thunderous drumming sound. The drummers stand on a log or mound as they beat their wings to protect their home range up to ten acres.
Large mixed flocks with male red-winged blackbirds will soon be migrating back. We’ll most likely hear them in trees or wetlands as they chatter with one of the first spring bird songs.
Woodcock also return for their spring courtship display that the male uses to attract females. The males begin their song and dance at sunset, in a field or clearing. He sings out, calling repeated “peents,” followed by an occasional bobbing of his head, a turn, and a repeat of the dance again while broadcasting his song in different directions. They then fly upward into the sky in a wide spiral, moving higher and higher. As he gets higher, the male’s wings whistle, creating a “twittering” sound. Finally they begin their descent downward, zig-zagging back and forth, down to the ground without a sound.
If spring fever has any of us in its grip, it is time to get outdoors! Walk, whether down the road or in your own forested back yard. There are many exciting signs that spring is on its way for us to see and enjoy!
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. Also discover us on the web at www.cablemuseum.org, on Facebook, or at our blogspot, http://cablemuseumnaturewatch.blogspot.com/ to learn more about our exhibits and programs.
Thursday, March 10, 2011
Weasels
Nature Watch
By Susan Thurn,
Cable Natural History Museum
Our neighbor asked about weasels because he has seen one running around in his yard. Wisconsin is home to three species of weasels – the long-tailed, short-tailed, and least weasels. They are 8-16 inches long, and with the exception of the least weasel, have black-tipped tails in the winter. The last time I saw a weasel I’m pretty sure it was a long-tailed weasel, about 16 inches long. Two of them were chasing each other around in the middle and side of the road, and so I stayed put in my car for quite some time, just watching their antics.
White in the winter, except for the white tail, long-tailed weasels are thought to be more nocturnal. They are active all winter long, and some evidence suggests that they may be more active during the day in the summer. They shed their fur twice a year in our climate from brown to white, while in a southern climate stay brown all year round. They live in unused burrows, uprooted tree roots, under rocks, or in rotting logs. They can be found in almost any habitat, but preferably one near water, as they drink a significant amount of water each day. Their home range can be up to 40 acres of land. Although a male’s home range may overlap many female home ranges, home ranges of adults of the same sex do not overlap.
On the long-tailed weasel menu we might find mice, voles, pocket gophers, chipmunks, rabbits, or other small mammals. They also eat insects, birds, or bird eggs. In winter they use the same pathways under the snow that mice, voles, or shrews have created to catch their mammal prey. They also follow prey into their burrows as well. A user of scent and sound to find their prey, they often bob their heads back and forth to sense where their prey is located. They probe every crevice or possible place searching on the hunt for a meal. Occasionally, long-tailed weasels will kill more prey than they can eat, and so will store it away for later, just as squirrels or blue jays cache their nuts.
The long-tailed weasel can swim and even climb trees. They also use vocalizations that include purrs, squeals, and squeaks, but usually only when they are disturbed. They are aggressive with intruders in their territory. They may release a musk that is strong smelling when frightened and during mating season.
One of my favorite snowshoe forays was when I followed weasel tracks. The tracks led up to some vole tracks, where the vole tracks disappeared, literally, to never be seen again. Imagine the excitement of discovering a weasel in our own backyard, popping up out of a burrow, or out of the snow after having eaten a vole dinner. It would bring a whole new meaning to the words, “pop, goes the weasel!”
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. Find it in Cable at 13470 County Highway M. Also discover us on the web at www.cablemuseum.org, on Facebook, or at our blogspot, http://cablemuseumnaturewatch.blogspot.com/ to learn more about our exhibits and programs.
By Susan Thurn,
Cable Natural History Museum
Our neighbor asked about weasels because he has seen one running around in his yard. Wisconsin is home to three species of weasels – the long-tailed, short-tailed, and least weasels. They are 8-16 inches long, and with the exception of the least weasel, have black-tipped tails in the winter. The last time I saw a weasel I’m pretty sure it was a long-tailed weasel, about 16 inches long. Two of them were chasing each other around in the middle and side of the road, and so I stayed put in my car for quite some time, just watching their antics.
White in the winter, except for the white tail, long-tailed weasels are thought to be more nocturnal. They are active all winter long, and some evidence suggests that they may be more active during the day in the summer. They shed their fur twice a year in our climate from brown to white, while in a southern climate stay brown all year round. They live in unused burrows, uprooted tree roots, under rocks, or in rotting logs. They can be found in almost any habitat, but preferably one near water, as they drink a significant amount of water each day. Their home range can be up to 40 acres of land. Although a male’s home range may overlap many female home ranges, home ranges of adults of the same sex do not overlap.
On the long-tailed weasel menu we might find mice, voles, pocket gophers, chipmunks, rabbits, or other small mammals. They also eat insects, birds, or bird eggs. In winter they use the same pathways under the snow that mice, voles, or shrews have created to catch their mammal prey. They also follow prey into their burrows as well. A user of scent and sound to find their prey, they often bob their heads back and forth to sense where their prey is located. They probe every crevice or possible place searching on the hunt for a meal. Occasionally, long-tailed weasels will kill more prey than they can eat, and so will store it away for later, just as squirrels or blue jays cache their nuts.
The long-tailed weasel can swim and even climb trees. They also use vocalizations that include purrs, squeals, and squeaks, but usually only when they are disturbed. They are aggressive with intruders in their territory. They may release a musk that is strong smelling when frightened and during mating season.
One of my favorite snowshoe forays was when I followed weasel tracks. The tracks led up to some vole tracks, where the vole tracks disappeared, literally, to never be seen again. Imagine the excitement of discovering a weasel in our own backyard, popping up out of a burrow, or out of the snow after having eaten a vole dinner. It would bring a whole new meaning to the words, “pop, goes the weasel!”
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. Find it in Cable at 13470 County Highway M. Also discover us on the web at www.cablemuseum.org, on Facebook, or at our blogspot, http://cablemuseumnaturewatch.blogspot.com/ to learn more about our exhibits and programs.
Wednesday, March 2, 2011
Aquatic Wonders
Nature Watch
By Susan Thurn,
Cable Natural History Museum
I owe an apology to a gray truck. It was over the weekend, while driving home from Hayward, that I spotted a river otter along the Namekagon River. I turned on the blinkers, braked quickly, and quickly pulled over to the side of the road, perhaps angering the truck behind me. It was irresistible, the opportunity to view an animal that is so amazing and enjoyable, watching them bound across the ice. I had to stop and share the observations with my family!
River otters are part of the weasel family. Comfortable in water, they have a tapered body that streamlines them for successful swimming, webbed feet, sharp hearing and scent abilities, and a sense of touch that gives them good dexterity. Their lungs are complex, with a larger right lung and different lobes in both sides, designed for aquatic breathing. Their airway is also shorter to improve breathing for this diving mammal. Even their mouth is designed well, with sharp canines for biting their prey, and large molars for breaking the hard shells of clams and other mollusks. River otters can dive down to 60 feet deep, can swim underwater for up to four minutes, and move almost 1200 feet underwater. One last amazing adaptation is that they dry themselves by rubbing on the ground, which also maintains the insulation value of their fur.
On land, otters can walk, bound, or slide, which is part of what makes them seem so playful, and what my family observed this otter doing. They slide across the snow or ice, mud banks and vegetated slopes, quickening their pace in efficient travel. They will excavate beaver dams to access water and in winter, use any opening in the ice.
Where do they sleep? Otters create a den or hole at the water’s edge, with many openings that allow them to enter or exit the water in several places. These exits also give them greater access to their prey.
When hunting, river otters will lunge quickly from an ambush to catch their food, or chase after prey. What is on their menu? They will eat small fish while floating at the surface, but take larger fish to the shore for their dining pleasure. Crayfish is another favorite food, according to scat that has been observed. They will also eat frogs, clams, mussels and snails, fruit, reptiles, amphibians, small mammals, and aquatic insects. They even eat plants and birds.
The river otter is more social than most animals in the weasel family. They fish together. They are playful, chasing or wrestling with each other. They will play catch and release with live prey. They communicate with chirping sounds, grunts, or even high pitched screams when mating or fighting.
I envy those who live along the water and have the occasional or frequent observations of this lively and fascinating mammal. Please post your own otter stories at the Museum’s blogspot listed below to share the wonder of this amazing creature that lives in 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 exhibit, “In a New Light” photographic exhibit focused on the St. Croix National Scenic Riverway. Find it in Cable at 13470 County Highway M. Also discover us on the web at www.cablemuseum.org, on Facebook, or at our blogspot, http://cablemuseumnaturewatch.blogspot.com/ to learn more about our exhibits and programs.
By Susan Thurn,
Cable Natural History Museum
I owe an apology to a gray truck. It was over the weekend, while driving home from Hayward, that I spotted a river otter along the Namekagon River. I turned on the blinkers, braked quickly, and quickly pulled over to the side of the road, perhaps angering the truck behind me. It was irresistible, the opportunity to view an animal that is so amazing and enjoyable, watching them bound across the ice. I had to stop and share the observations with my family!
River otters are part of the weasel family. Comfortable in water, they have a tapered body that streamlines them for successful swimming, webbed feet, sharp hearing and scent abilities, and a sense of touch that gives them good dexterity. Their lungs are complex, with a larger right lung and different lobes in both sides, designed for aquatic breathing. Their airway is also shorter to improve breathing for this diving mammal. Even their mouth is designed well, with sharp canines for biting their prey, and large molars for breaking the hard shells of clams and other mollusks. River otters can dive down to 60 feet deep, can swim underwater for up to four minutes, and move almost 1200 feet underwater. One last amazing adaptation is that they dry themselves by rubbing on the ground, which also maintains the insulation value of their fur.
On land, otters can walk, bound, or slide, which is part of what makes them seem so playful, and what my family observed this otter doing. They slide across the snow or ice, mud banks and vegetated slopes, quickening their pace in efficient travel. They will excavate beaver dams to access water and in winter, use any opening in the ice.
Where do they sleep? Otters create a den or hole at the water’s edge, with many openings that allow them to enter or exit the water in several places. These exits also give them greater access to their prey.
When hunting, river otters will lunge quickly from an ambush to catch their food, or chase after prey. What is on their menu? They will eat small fish while floating at the surface, but take larger fish to the shore for their dining pleasure. Crayfish is another favorite food, according to scat that has been observed. They will also eat frogs, clams, mussels and snails, fruit, reptiles, amphibians, small mammals, and aquatic insects. They even eat plants and birds.
The river otter is more social than most animals in the weasel family. They fish together. They are playful, chasing or wrestling with each other. They will play catch and release with live prey. They communicate with chirping sounds, grunts, or even high pitched screams when mating or fighting.
I envy those who live along the water and have the occasional or frequent observations of this lively and fascinating mammal. Please post your own otter stories at the Museum’s blogspot listed below to share the wonder of this amazing creature that lives in 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 exhibit, “In a New Light” photographic exhibit focused on the St. Croix National Scenic Riverway. Find it in Cable at 13470 County Highway M. Also discover us on the web at www.cablemuseum.org, on Facebook, or at our blogspot, http://cablemuseumnaturewatch.blogspot.com/ to learn more about our exhibits and programs.
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