Operation Owl Rescue

On Christmas Day, I found myself driving from Lutsen, Minn., to Duluth with a very unusual package next to my skis and duffle bag. On my way home from a short trip near Thunder Bay, Ontario, a Facebook post caught my eye. “…large grey owl on the side of the road. They stopped to investigate, and noticed that its wing appears to be broken. Given our location (Lutsen) and the date (Christmas Eve), what should we do?”

Minutes later, I passed a group of three people trudging up a snowy road ditch with a blanket and a cardboard box. As it turns out, that crew included Christine Salomon and her two teens, Ezra and Macy. When I met Christine and Macy the next morning in Lutsen to help transport the owl, they filled me in on the rest of the story.

This Great Gray Owl was injured by a car on Highway 61 near Lutsen, MN. The rescuers took this photo to help wildlife rehabilitators assess the owl’s identification and injuries and then quickly backed off. Photo by Christine Salomon.

Christine had called the hotline for Wildwoods wildlife rehab facility in Duluth and received instructions on how to rescue the owl. That explained the blanket for protection from the raptor’s sharp talons, and the box to carry the owl without further injuring them. “It was not that different than picking up one of my chickens,” explained Macy nonchalantly. “The owl was all puffy until I picked them up, and then they just deflated.”

Great Gray Owls, one of the tallest owls in the U.S., are mostly made of feathers. Living in the taiga of Canada, Scandinavia, Siberia, Mongolia, and Minnesota, they need lots of insultation. They also need lots of food, and this year more owls than usual have come south in search of tasty voles.

Macy and Ezra placed the owl, still inside the sturdy box with lots of ventilation, in an unheated sauna for the night. Being in quiet darkness is the least stressful environment for an injured bird. The owl’s need for transport to Duluth on Christmas Day fit with my own travel plans back to Cable, which is how I ended up in the empty parking lot of a liquor store in Lutsen making the handoff.

Macy and Christine Salomon with the Great Gray Owl in the box.
We made a quick and quiet hand-off.

To reassure ourselves that the owl was still alive, Christine opened one of the flaps on the box. Staring up at us were two giant yellow eyes nestled into satellite dishes of gray-patterned feathers that funnel sound into the owl’s hidden ears. Just like the more common Great Horned and Barred Owls, Great Grays use their excellent hearing to locate mice and voles beneath the snow and plunge in talon-first to grab them.

This owl probably had swooped down toward a mammal snack in the road ditch, and didn’t see an oncoming car. Both natural weed seeds and food scraps thrown out of car windows can attract small mammals to the road ditch and put wildlife in danger.

I was mindful of my precious cargo on the long drive as I reduced my speed on corners, eased into stoplights, and kept the radio off. Jessica LaBumbard, executive director of Wildwoods, met me outside the door of their little facility in Duluth. With another owl already in their care, the possibility of spreading avian influenza was a risk she didn’t want to take. Plus, she would have needed the help of another staff member to handle the owl safely.

Instead, a third car pulled into their lot, and two of Wildwoods’ long-time volunteers whisked the owl away to The Raptor Center in St. Paul for advanced care. I asked if they were already heading in that direction. “Nope,” they said with big smiles. They were just happy to help.

Jessica and the small staff at Wildwoods have been busy lately. They helped rescue five owls in the matter of just a few days around Christmas. All were injured by cars, and not all of them survived.

One owl in particular, a Snowy Owl found in the grill of a car in the parking lot at the Bentleyville Tour of Lights in Duluth, made the national news. I asked Jessica what she thought those stories overlooked. “I cringe at all the photos of the owls with lights and people,” she told me. “Owls are terrified of us, and the best thing we can do is get them somewhere quiet and dark, away from human voices, as soon as possible. Our roads are not designed for wildlife, which makes these injuries unavoidable. But if people can slow down a bit, that helps,” she added.

Even after I’d delivered my unusual package, I found myself driving in silence. My thoughts were with all the rescued owls, wishing that their injuries could be healed. I’d just seen my first Great Gray Owl, and even that tiny glimpse had been unforgettable. With any luck, and with the hard work of all the rehabilitators and their rescue volunteers, and conservationists, the next Great Gray I’ll see will be healthy and in the wild.

If you find an injured raptor, never try to help them until you have spoken with a licensed wildlife rehabilitator. Only move them if they are in immediate danger and you aren’t putting yourself in danger. It is illegal to possess a raptor unless you are transporting them directly to a licensed rehabilitator.

Here are a few places you can call about injured raptors in Minnesota and Wisconsin:

• Wildwoods, Duluth, MN, 218-491-3604
• The Raptor Center, St. Paul, MN, 612-624-4745
• The Raptor Center has an excellent guide to handling on their website.
• Winged Freedom Raptor Hospital, Spooner, WI, 715 781-2595
• Raptor Education Group, Inc., Antigo, WI, 715-623-4015
• Hoo’s Woods Raptor Center, Milton, WI, 608-883-2795
• WI DNR Wildlife Hotline 608-267-0866
• Wisconsin DNR Wildlife Rehab Directory

All these facilities have websites where you can find out more, sign up to volunteer, and donate to support their important work!



Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, is available to purchase at www.cablemuseum.org/books and at your local independent bookstore, too.

For more than 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. The Museum is open with our brand-new exhibit: “Anaamaagon: Under the Snow.” Our Winter Calendar is open for registration! Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.

Wilson’s Warbler WOW

Gathered around a bonfire on the Winter Solstice, the hostess asked us each to share one moment from the past year that made us go, “Wow!” Being residents of the Northwoods, we had each experienced many such moments, she acknowledged, but in the interest of time, we must choose just one. “Wow” moments flickered through my memory with the same warmth and brightness of the campfire’s flames. Despite the fact that my year had included rafting the Colorado River through the Grand Canyon, my favorite “wow” moment happened on a river much closer to home.

The Winter Solstice Fire

One lovely afternoon last May, I set out with a friend to paddle an upper section of the Namekagon River. Flights of “mackerel sky” clouds patterned the sky, but plenty of blue shone through. The white blossoms of highbush cranberries and wild cherry trees accented the bright greens of brand-new leaves.

Our goal was to experience the evening chorus of birds as they fueled up on insects before taking off on another night of migration, or defended their newly claimed nesting territory against intruders. Common Yellowthroat Warblers, with their rakish black eye masks, shouted witchety-witchety-witchety from deep within the alders. Dark gray Eastern Kingbirds darted off their perches to catch recently hatched insects. And Gray Catbirds announced their locations with loud mews.

As we reveled in the vibrant life coursing through the spring evening, while also gaining satisfaction from being able to identify so many birds, a Mary Oliver poem came to mind.

“Don't mind my inexplicable delight / in knowing your name, / little Wilson's Warbler” 

she wrote.

I quoted this poem to my friend, and then focused back on my steering, since we were coming up to a corner and then a potentially tricky slide down an old, submerged dam under a bridge. As I swung us wide into the corner to make it a straight shot, a burst of twittering, movement, and flashes of yellow in the alder shrubs drew my attention. Squinting, I thought I spotted a black cap on one of the tiny heads, and quickly pulled into an eddy.

Sure enough, our binoculars revealed a flock of half-a-dozen or more little birds, “yellow as a lemon, with a smooth, black cap…” as Mary Oliver described them. Laughing in delight, we felt like we’d just conjured these Wilson’s Warblers with her poem.

Wilson’s Warblers are bright yellow with a little black cap.
Photo by Rhododendrites - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=105248001

That poem, titled Bird in a Pepper Tree, must have been written on a trip to Mexico or Central America, where both the range of the pepper tree and the winter habitat of Wilson’s Warblers overlap. Each spring, the birds leave this narrow refuge and fan out across the continent toward breeding grounds in the far north. Males tend to migrate faster and earlier, rushing north to claim breeding territories ahead of the females’ arrival. Indeed, the little flock, each with a very distinct black cap, all appeared to be males.

As they bounced like fresh popcorn through the willow and alder thickets near the river’s edge, the Wilson’s Warblers perfectly matched the descriptions of their behavior in the bird guides. They tend to stick to the understory, unlike other warblers who will pause on a high perch to belt out a song. Surrounded by leaves, the Wilson’s Warblers pluck caterpillars and aphids off the bushes, and if a flying insect catches their eye, they’ll take to the wing to nab it, returning to nearly the same perch.

It was their greenish-yellow wings, black feathers on their crown, and darting behavior that earned these little birds their first English name: “Green Black-capt Flycatchers” in 1811. Alexander Wilson, an American ornithologist, called them this, following his preference for descriptive names. Ironically, after his death, other ornithologists changed the bird’s name to honor him.

The reason we can call this warbler by such a simple, alliterative name, instead of the harder-to-remember Cardellina pusilla, is that The American Ornithological Society (AOS) has standardized common names. Those standards may soon be modified. In 2023, the AOS committed to “changing all English-language names of birds within its geographic jurisdiction that are named directly after people (eponyms)…”

This decision is not without controversy, but I’m in favor of the change for the simple reason that it feels quite arrogant to call any wild being a possession of someone. Despite the name’s implication, Alexander Wilson doesn’t have any ownership over the Wilson’s Warbler, and never believed he did. Although Mary Oliver died several years before the AOS’s decision, I think she would have agreed. The last line in her poem, after delighting in observing the bird’s behavior and being able to identify them, was “a name is not a leash.”

And yet, by some magic, Mary’s poem and these handsome little warblers were tied together in a moment that made us say, “wow!”

Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, is available to purchase at www.cablemuseum.org/books and at your local independent bookstore, too.

For more than 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. The Museum is open with our brand-new exhibit: “Anaamaagon: Under the Snow.” Our Winter Calendar is open for registration! Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.

A Black-capped Brain

Washing the dishes after a family dinner is a big job, especially because my mom’s kitchen doesn’t have a dishwasher. But the window over the kitchen sink looks out on several bird feeders, and my dad makes sure they are always full of seed and ready to entertain.

Black-capped chickadees are the most fun. They dart in, grab a single seed, and swoop off to eat it in a spot that’s less exposed than the feeder on a second-floor deck railing. This is similar to the feeding strategy of a ruffed grouse, but on a much smaller scale. As I wrote last week, grouse will stuff their crop full of buds and catkins for about twenty minutes, and then fly off to a protected place to digest all night. Grouse increase the size of their gut to accommodate this practice, but chickadees have kept their stomachs small and increased their brain size instead.

Inside a black-capped chickadees big, adorable head is a big, effective brain.
Photo by Emily Stone

Chickadees gain up to ten percent of their body weight in fat each day, and burn it off each night to stay warm. Even though they wedge themselves into a tiny tree cavity, puff up their feathers, and drop their body temperature by 18 degrees, they still need to shiver all night to generate heat. They don’t have energy to waste by maintaining both a large digestive system and a large brain. Getting too bulky would leave chickadees less agile and more vulnerable to predation, anyway.

One way that they find a balance is by hiding seeds—essentially storing fat outside of their body. Often, when a chickadee nabs a seed from your feeder, they don’t eat it; they stash it away for later in the bark of a tree or under a leafy lichen. This allows them to dole out their calories more efficiently and prepare for a “rainy day.” Eating just a few nutrient-rich seeds at a time also means that their stomach can stay small.

Chickadees cache as many as one hundred thousand food items per year. Unlike squirrels, chickadees don’t go sniffing out their hidden seeds. In lab experiments, scientists have determined that chickadees use visual cues—especially big ones like the location of nearby trees—to re-locate their cache sites. Not only do chickadees remember their seed cache sites, but they also remember details like which food items were the most favored and which seeds have already been eaten by them or by a thief.

To support such an incredible memory, chickadees grow 30 percent more neurons in the fall when caching behavior peaks. Then, as they empty out their cache locations, the neurons encoding that information wither away, and their brain shrinks toward spring. The title of a 2014 article by Kozlovsky, et. al. says it all: “Chickadees with bigger brains have smaller digestive tracts.” Chickadees, especially ones who live in the coldest and most variable habitats, have figured out how to eat smarter, not bigger. That could easily be my New Year’s resolution.

Last April, researchers at Columbia University added to our understanding of chickadee memory. Selmaan Chettih, and Emily Mackevicius, with the help of principal investigator Dmitriy Aronov, placed chickadees in what they call an arena—which sounds to me like an avian version of the Hunger Games! The arenas were built to look like a chickadee’s usual habitat, with plenty of nooks and crannies for hiding seeds.

As the chickadees conducted their typical caching behavior, the scientists recorded their movements with cameras, while also monitoring activity in their brains. Each time a chickadee hid a seed, their neurons fired in a unique pattern. When the chickadee retrieved that same seed, the pattern was repeated. Each cache got its own pattern. The scientists dubbed these “neural barcodes.” The birds are essentially creating their own system for inventory and checkout—just like at a grocery store!

Even though chickadees and grouse have evolved strategies that are on opposite ends of the brain-stomach spectrum, they are both good at surviving when we leave their habitat and natural food sources intact. Even when chickadees have easy access to your feeder, only about 21 percent of their daily energy comes from your generosity. The rest they gather from the wild.

As a result, the scientific consensus is that birds don’t become dependent on feeders like the ones in view of my mom’s kitchen sink, and will find other food sources if you go on vacation. That said, your gifts are appreciated. Years ago, Margaret Brittingham and Stanely Temple at the University of Wisconsin—Madison, observed that when cold temperatures lasted for more than five days, chickadees with access to bird feeders had higher survival rates.

Since I love watching chickadees while I wash dishes, I’m quite happy to continue feeding their big, black-capped brains.

Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, is available to purchase at www.cablemuseum.org/books and at your local independent bookstore, too.

For more than 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. The Museum is open with our brand-new exhibit: “Anaamaagon: Under the Snow.” Our Winter Calendar is open for registration! Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.

A Stomach for the Holidays

While digesting one of the many rounds of holiday feasts and leftovers, with plates of cookies in between, a headline caught my eye: “Big brains or big guts: Choose one.”

As much as the post-holiday-dinner-brain-fog is real, I don’t love the implications of those options.

Luckily, the article wasn’t about humans. It was examining birds in cold, highly variable habitats, and their struggle to survive. Essentially, birds have two options: spend energy maintaining a big brain that allows them to find high-quality food, or spend energy maintaining a large stomach that can make low-quality food sufficient in high quantities. According to the research, if you are a bird who needs to survive cold winters, you must choose one. There’s no middle ground.

Last week I wrote about ruffed grouse feeding on the berries, buds, and twigs of mountain-ash trees. Grouse are the poster children for the success of birds with large stomachs and small brains. Even as ruffed grouse fly into windows, dart out into the road, and strut through my campsite unaware, I’ve tried to defend their intelligence. They are successful as a species after all, but that’s due to an evolutionary-level intelligence rather than individual intellect.

A ruffed grouse sits and digests the contents of their large stomach in a protected place. 

Photo by Kevin Friedman.

The benefit to having a small brain is that grouse put their energy into having a large stomach—and growing it even bigger for the winter. Back in the 1960s, two biologists “sampled” spruce grouse in Alberta, CAN, every month for a year. (I hope that they ate those poor, dissected grouse for dinner and didn’t let them go to waste.) Pendergast and Boag found that the grouse’s gizzards grew by 75% in winter, and the rest of their digestive tract increased in length by 40%.

The scientists hypothesized that when grouse switch from summer berries and insects to winter conifer needles (for the spruce grouse) and buds, twigs, and catkins (for the ruffed grouse) their gizzards must expand to hold more food and get strong to grind tougher food. Captive birds kept as controls and fed nice, digestible food didn’t exhibit any seasonal change in their digestive systems. Another study showed that stomach size decreases as grouse and ptarmigan diets became more digestible, so needle-eating spruce grouse are at the large end of the stomach spectrum among their cousins. That their brain is at the small end is evidenced by spruce grouse’s nickname “fool hen.”

Having a robust digestive system is made even more important because grouse aren’t good at storing fat. They must eat a lot every day to fuel their metabolism and get through winter. But while they are feeding—often in the tops of aspen trees—they are exposed to cold, wind, and predators. Their solution is to eat fast and save digestion for later.

While exposed, grouse feed quickly, packing 10 percent of their bodyweight in food into a pouch in their esophagus called a crop. Then they hide away in a dense thicket, or dive into a snow roost, to digest in peace and safety. This strategy doesn’t keep every grouse alive, but come spring, the survivors have lots of babies who need little parental care, and the population will rebound.

Other animals who have similar diets to grouse also grow bigger stomachs in the winter to accommodate fibrous food. Voles, for example, show a winter increase in the mass of their gastrointestinal tract, and especially the cecum. The cecum is a pouch in between the large and small intestines where microbes ferment fiber and make nutrients available to the vole.

The stomachs of white-tailed deer also expand in the winter to accommodate a larger quantity of lower quality food. And deer, with their four stomachs, have a much more elaborate system of microbial fermentation than the voles. The catch is that their microbes adapt to seasonal changes in their diet, and feeding deer corn or other supplements in the winter can kill them through rumen acidosis.

Of course, not all animals grow bigger stomachs in the winter. Shrews shrink their entire body, even their skull, by about 20 percent so that their metabolism can keep running at full tilt but survive on less fuel. Fish, like pumpkinseeds, who become dormant in the cold winter water, save energy by shrinking their gut until right before spring spawning.

And then there are the birds at the opposite end of the spectrum from grouse: black-capped chickadees. Their brains, not their stomachs, get bigger in winter. Let that information digest, and I’ll tell you more next week.

Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, is available to purchase at www.cablemuseum.org/books and at your local independent bookstore, too.

For more than 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. The Museum is open with our brand-new exhibit: “Anaamaagon: Under the Snow.” Our Winter Calendar is open for registration! Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.

The Color Splash of Mountain-ash

In a landscape of winter white, bits of color really pop. Recently I was on the North Shore of Minnesota when they received several inches of fluffy, wonderful snow. Gray clouds hung low and continued to sprinkle fairy dust throughout the following day. Out on the cross-country ski trails above Grand Marais, my yellow jacket shone against the snow. When a strip of blue sky finally peeked through the clouds, that, too, glowed brightly. Full sun would have been blinding!

Spots of red also caught my eye. The forest seemed decked out for Christmas with clusters of mountain-ash berries adding color in the woods along the ski trails, around town, and on the rocky shore of Lake Superior. One section of scrubby forest between Highway 61 and the lake seemed to be almost entirely composed of berry-laden mountain-ash trees.

As the days grow ever shorter and darker this time of year, splashes of color like these berries do wonders for my mental health. Ruffed grouse appreciate them even more, I’m sure, as they perch in the dark purple twigs and nibble both berries and buds. The berries are acidic enough to last on the tree all winter, but if a flock of cedar waxwings descends, all the fruits may disappear in a single day. Thrushes, jays, catbirds, and grosbeaks, plus squirrels and small mammals, sometimes share in the feast.

Mountain-ash berries brighten up the winter woods, especially along the North Shore of Lake Superior. Photo by Kevin Friedman.

Grouse eating mountain-ash berries. Photo by Kevin Friedman.

The twigs of mountain-ash apparently are tasty, too, or at least nutritious. When I taught a wolf ecology course on the North Shore years ago, we observed the impacts of deer browse in different parts of wolf territories. Any mountain-ash short enough for deer to reach was deformed from their nibbling. On Isle Royale, scientists observed that over eighty percent of mountain-ash stems in study plots were browsed by moose. Moose have the advantage of height. Snowshoe hares must browse the lowest twigs with their sharp incisors, or wait for deep snow to give them a lift.

Photo by Emily Stone.

Back in the day, when I took a plant identification course at Northland College, we only learned two species—American mountain-ash (a native) and European mountain-ash (Sorbus aucuparia, introduced for landscaping). So, for years, when I’ve found these trees away from towns, I’ve called them all Sorbus americana. Recently, I’ve discovered that showy mountain-ash, Sorbus decora, is also native here, and is more common, at least in Wisconsin.

The three species are almost identical to the casual observer. While the leaves are slightly different sizes and shapes, this time of year the hairiness of the buds and berry stems seems to be the best distinguishing characteristic. The buds of the European species will be covered with long, white hairs. Showy mountain-ash twigs and buds are pubescent (with short hairs) and American mountain-ash twigs and buds are usually smooth and hairless.

I always thought this tree was a European Mountain-ash. Now I'm not so sure--but it's been cut down so I can't go back and look closer! Photo by Emily Stone.

All of these species are good wildlife and landscaping trees, although planting the native mountain-ashes is preferred, since the European ones have been known to escape into the wild. While their showy, rounded clusters of white flowers don’t look like roses from afar, they are all part of the Rose Family. A closer look at the flowers reveals five white petals very similar to the blossoms on their cousins: strawberries, raspberries, cherries, and apples. Even the fruits of mountain-ash look like mini apples.

I took this photo of mountain-ash flowers on Hunger Mountain in Vermont during graduate school. From the leave length-to-width ration I measured off the photo, this is Sorbus decorum. Photo by Emily Stone.

Mountain-ash drupes that look like mini apples. Photo by Kevin Friedman. 

The hyphen in their name indicates that they aren’t really related to ash trees. Mountain-ash are called that because they have compound leaves with long, narrow leaflets, similar to true ash trees. Unlike true ash trees, these wonderful wildlife trees won’t be impacted by the deadly emerald ash borer insects.

Ash-like leaves on a mountain-ash. Photo by Emily Stone.

Both of our native species reach their southwestern edge in northern Wisconsin and Minnesota, and extend north and east from there. American mountain-ash also extends down the spine of the Appalachians. The happiest specimens seem to be concentrated along the north shores of Lake Superior and Lake Huron. They are quite common among the balsam fir trees on Isle Royale as well. On the water-limited bedrock along Artist’s Point in Grand Marais, I’ve noticed they can remain quite shrubby, and a heat wave last summer left their leaves brown and crispy.

The color these wonderful berries bring to our winter woods is only one reason I enjoy them. Getting to watch and listen to the flocks of birds they attract is another. And now, the challenge of learning to distinguish the two native species will give me an excuse to look more closely at their leaves and twigs. In doing that, I bet I’ll learn something else new, too.

Cedar waxwing in a tree that I once thought was European mountain-ash, and now can't be sure. Photo by Emily Stone. 

Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, is available to purchase at www.cablemuseum.org/books and at your local independent bookstore, too.

For more than 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. The Museum is open with our brand-new exhibit: “Anaamaagon: Under the Snow.” Our Winter Calendar is open for registration! Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.

Red-eyed Vireo Nests: Hidden Treasures of See-Through Season

Cold air filled my lungs as I climbed yet another flight of stairs up to the observation tower at Copper Falls State Park. It was interesting looking out through the twigs and trunks. The lack of leaves in this “see-through season” reveals aspects of the landscape otherwise obscured. For example, “Check out that nest!” I exclaimed to my friend, and we admired the small cup suspended between a Y in the sugar maple twigs. It was a lovely reminder of a favorite summer resident, now gone for the winter.

Can you see through the forest and spot the vireo nest? It's fun to get to look down on one! Photo by Emily Stone.

The placement of the nest dangling below the forked twigs, plus the few pale strips of paper from a bald-faced hornet nest woven among grass, bark, and pine needles, told me that it was likely built by a red-eyed vireo. While red-eyed vireos are one of the most common birds of eastern and central North America, these small, olive-green songbirds are hard to see among the leaves in the dense forests they prefer. Once the leaves fall, though, their nests are suddenly one of the most visible and recognizable of any songbird.

It's the female vireo who builds the nest in spring. She usually chooses a deciduous tree or shrub and places the nest 10-15 feet above the ground, and far enough out from the trunk so that it doesn’t block their view. Suspending a nest near the tips of thin branches reduces access for heavy nest predators like squirrels. On the chosen branch, the vireo weaves together fibrous strips of the inner bark of trees and other plant fibers to suspend the nest between the twigs. Pine needles often line the 2-inch-diameter inner cup. Spider webs help stick it all together.

As mentioned above, vireos often decorate the outside of their masterpiece with paper strips stolen from last season’s abandoned bald-faced hornet nests, even when those nests are not found nearby. Naturalists suspect that décor can trick potential predators into thinking it’s the nest of a furious stinger instead of a tasty songbird. Strips of birch bark often add to the papery look.

Almost every bird nest is a work of art. They are also feats of engineering that gently cup fragile eggs and chicks while withstanding storms, and then remain intact long past their intended use. Plus, they were constructed without opposable thumbs!

There’s a display at the Cable Natural History Museum that reinforces my awe. A Museum naturalist, decades ago, deconstructed a red-eyed vireo nest and catalogued each component. The nest included: 1 cherry stem, 1 piece of paper, 1 ball of tree sap, 2 pieces of thread, 7 fir needles, 9 plant buds, 69 pine needle sheaths, 16 pieces of hornet nest, 24 twigs, 50 animal hairs, 346 pieces of birch bark, 347 pine needles, 427 pieces of inner bark, and 16 pieces of spider web. The naturalist arranged these objects, minus the spider webs, in a beautiful display that hangs in our classroom.

This deconstructed vireo nest is a favorite display at the Cable Natural History Museum. The number of different nest materials is astounding! Photo by Emily Stone.

Despite the birds’ hard work, and the hornet paper, red-eyed vireo nests are vulnerable to nest parasitism by brown-headed cowbirds. When vireos can place their nests in the heart of a forest this is less common, but any vireo nest near a forest edge may end up with a cowbird egg among the 3-4 vireo eggs. The cowbird hatches first, grows faster and bigger, and will often push their adopted siblings out of the nest. Occasionally vireos will cover up the cowbird eggs and try again, but more often the parents just feed the big baby as one of their own. Vireos may nest multiple times per summer, especially if early nests fail.

Recently I noticed two vireo nests in the tops of trees surrounding my own driveway. Although the nests are much higher than average for a red-eyed vireo, that was the only vireo species I heard singing last summer. Warbling vireos are known to nest up high, but I would have recognized their run-on song, which sounds like them saying, as if to a caterpillar, “when I see you, I will squeeze you, and I’ll squeeze you ‘til you squirt!” Instead, I heard red-eyed vireos singing the incessant phrases “hear I am, over here, in a tree, look at me, vireo!”

All summer, it’s much easier to hear red-eyed vireos singing than to actually see one high in the treetops. This signing male was a lucky find! Photo by Emily Stone.

As their abandoned nests fill with white snow instead of white eggs, the vireos themselves are filling up on fruit in the Amazon basin of South America. When they return next spring, the females will start building new nests. Once the leaves fall, we’ll have a whole new set of treasures to discover in “see-through season.”

Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, is available to purchase at www.cablemuseum.org/books and at your local independent bookstore, too.

For more than 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. The Museum is open with our brand-new exhibit: “Anaamaagon: Under the Snow.” Our Winter Calendar is open for registration! Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.

Winter Songs of White-Throated Sparrows

During a recent week-long visit to the Washington D.C. area, finding pockets of nature with plenty of birds was a boon to our sanity. Early in the week, my partner and I drove west to the little town of Linden, Virginia, which provided the nearest access to the Appalachian Trail. Even as we crossed the gravel parking lot toward the oak-filled forest and uphill climb, a wistful-sounding white-throated sparrow sang from the brush. We looked at each other and grinned.

The rhythmic whistle of white-throated sparrows is part of the spring and summer soundtrack of the Northwoods. No hike or paddle is complete without their song. Two decades ago, while my parents helped me pack for a May trip to the Boundary Waters, this was the one song they’d insisted I learn to recognize. Luckily, it wasn’t hard. The white-throat’s pattern of two long starter notes followed by three sets of triplets is often described with the mnemonic “Oh, sweet Canada, Canada, Canada” and is quite distinctive.

But it’s been a month or more since we heard the last sparrow sing goodbye to the Northwoods as they headed south. I felt a little sheepish, realizing I’d never paid much attention to where they were going. Virginia, as it turns out, is in the core of their winter range. As we hiked, it seemed like almost every scritching sound in the underbrush turned out to be a foraging sparrow using their two-footed hops to unearth seeds in the duff. Getting a glimpse of snazzy black-and-white head stripes, yellow near the eyes, and the signature white throat patch confirmed their identity.

White-throated Sparrow. Photo by Larry Stone. 

Higher up in the trees, cardinals whistled, tufted titmice peter-peter-petered, Carolina wrens chattered energetically, and Carolina chickadees scolded each other. These are common winter compatriots of the white-throated sparrows.

A few days later, we crossed over a babbling brook on a wide wooden bridge and into the “R. Randolph Buckley ‘8-Acre’ Park” in Clifton, Virginia. Large beech trees, sycamores, oaks, maples, and pines, plus musclewood and a blooming witch hazel, welcomed us into this little neighborhood woodland. As we followed our ears to a white-breasted nuthatch high in a pine tree, a song burst out of a bush beside us. The white-throated sparrow riffed on the usual song, experimenting with a gravely “sweet can-a-NA-da can-a!” “Jazzy!” We laughed to each other. Listen here!

I don’t usually expect birds to sing in their winter habitat. Birds’ songs are typically used to attract mates and defend territories, and therefore are most useful in spring and summer. Many birds get by using simple call notes to communicate within a flock over the winter. So, we figured we were hearing young males practicing for the coming year. That would also explain why the amateurs’ “sub-songs” were tending shorter and with more variations in rhythm and tone. As it turns out, that was only part of the story.

Singing on their wintering grounds is more than just training for the youngsters. It’s an important avenue for learning new songs! In 1999, two ornithologists in western Canada heard white-throated sparrows singing a shorter song. Instead of the triplet “can-a-da,” they heard a doublet, “can-a.” Over the next few years, scientists studied older recordings of the white-throat’s songs, and made new observations, too. In ten years, by 2019, the new song had been adopted as far east as Ontario. Currently, you can only hear the original song in the farthest east populations.

How did the new song spread so quickly when these sparrows breed clear across Canada? They learned from each other on their wintering grounds and then took the new “slang” back home in spring. This goes against traditional wisdom, that young birds learn to sing from their fathers before they leave home. Song spread is facilitated because male sparrows from all over are extra concentrated. They tend to stick to the north end of their winter range—poised for a rapid return to claim a breeding territory in spring—while females go farther south to avoid competition with the males.

Just singing a new song isn’t enough to make birds successful, though. If it’s not recognizable to your own species, or sounds weird, a new song might hurt your breeding success. In this case, females prefer the novelty of the males’ new song, and this reinforces the change.

I’d heard about the white-throated sparrow’s changing songs before, but it wasn’t until I investigated the young birds’ jazzy riff that I realized it had taken over so completely. I’ve been trying to shoehorn their summer songs into the familiar “Oh, sweet Canada” mnemonic, and attributing variation to lazy birds. Now I know that something much more interesting is going on. Just like the sparrows, I learned something new in their winter habitat.

Emily’s award-winning second book, Natural Connections: Dreaming of an Elfin Skimmer, is available to purchase at www.cablemuseum.org/books and at your local independent bookstore, too.

For more than 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. The Museum is open with our brand-new exhibit: “Anaamaagon: Under the Snow.” Our Winter Calendar is open for registration! Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.