The Varied Thrush: Not Just Another Birdbrain

Male varied thrush resting on a snowy cedar bough.

A forest bird never wants a cage

—Henrik Ibsen (1828-1906)

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The varied thrush (Ixoreus naevius) is a handsome black and orange bird that is slightly smaller than the American robin (Turdus migratorius)—also a thrush.  A native species, and year-round resident, it is a bird of wet Northwest forests, and migrates locally with the seasons.  Males are more colorful than females having a dark orange eye stripe, throat, breast, wing bars, legs, and an orange-gray belly.  Males also have a black face mask, and breast band, and a slate-gray back and tail.  Females are paler, yellowish-orange with slate-gray markings, and a less pronounced breast band.  

In the mountain foothills, their flocks arrive in autumn (about mid October) when the deciduous leaves of red alder (Alnus rubra) and bigleaf maple (Acer macrophyllum) are on the ground.  We counted thirty-four varied thrushes last autumn, which is about average.  It’s sad to think that we could see fewer birds in the years ahead if logging of mature forests continues. 

—Journal entry:  October 21—the first varied thrushes have arrived!

Female varied thrush (above and below)–note the slate-gray back, and broken breast band.

This handsome male waits for a turn at the feeder.

A varied thrush has just flown through the links of the cyclone fence–a common occurrence.

Through the autumn and winter months, they spend their time behaving much like free range chickens—poking, prodding, kicking, and scratching at rain-soaked leaves.  They attack them vigorously.  With a flick of its wings, the thrush lunges forward, and grasps a leaf with its beak.  With all its might, it turns it over to unveil what is hiding underneath.  Turning wet leaves isn’t easy, but is usually accomplished on the first try.  Larger leaves, such as bigleaf maple that are the size of dinner plates, can take two or more attempts.  The thrush cocks its head, eyes the ground, and then quickly devours a menagerie of microscopic insects known as arthropods, a highly nutritious food that provides protein and energy. 

This female enjoys a sun break.

A male with the sun on his back.

By March, more than half of the flock has left.  By early April, maybe a half-dozen remain.  With the arrival of spring, those still with us grow anxious, until they too return to the old growth forests where they will raise their broods, devour fat insects, dine on protein-rich conifer seeds (acorns in drier habitats) and plump juicy berries until autumn sends them back to our woods. 

—Journal entry:  April 14—only a half-dozen varied thrushes in the woods today.  I expect they too will be gone before the week is out.

One of the things we enjoy most about the varied thrush is its song.  Not to be mistaken with its call, which is a soft took, took, tschook, but its happy song; a song of soft chirps and nasal whistles that sound like fairy flutes, bells, and chimes rolled into one—a song sung best at dusk and dawn.  

Underneath all that beauty and song, the varied thrush doesn’t seem to be a bird with many smarts.  Timid, they spook easily and scatter like buckshot, which makes them only second to the pine siskin (Carduelis pinus) for window strikes.  While this in-flight scatter tactic may prove useful in open areas to confuse predators, it can be lethal around dwellings and windows.  Unlike the pine siskin, however, whose little bodies I sometimes find beneath a window, the only evidence of the varied thrush are black and orange feathers stuck to the glass panes.  

Although relieved, I found it puzzling.  How can the varied thrush have so many window strikes, yet live to sing another song?  In nature, there are always more questions than answers.  Then one afternoon, there was a loud thunk!  Another varied thrush had struck, this time, the sliding glass door.  The poor bird hit so hard, I thought for sure it broke its neck and the glass.  Unlike the other times, I saw what happened.  Just before impact, the thrush pulled back, striking the glass not with its head, but with its breast, which softened the blow.  The thrush, minus a few feathers, paused a moment, ruffled its feathers, and then flew away. 

Windows are not this bird’s only obstacle.  Cyclone fencing is also a problem for them.  While squirrels crawl through it, raccoons climb over it, skunks dig under it, and most birds fly over it, the varied thrush flies through it, and not with the greatest of ease.  Barely able to squeeze their plump, feathery bodies through the chain links, they hit the fence.  There’s a lot of clinking as they bounce like balls in a batting cage.  Why they just don’t fly over the darn thing is beyond me.   

While this only reinforced how I felt of their intelligence, or lack thereof, I saw something recently that made me reconsider.  Among our winter flock a female with an injury to her right foot had caused it to clench like a fist.  Fortunately, the leg wasn’t broken, but the foot was useless, and would never clasp a branch or scratch at the ground again.  In nature, such occurrences often mean certain death, and we did not expect her to survive the winter. 

This shot clearly shows the clenched foot.

With the arrival of spring, we were surprised and delighted she had made it!  About a week passed without our seeing her, and we assumed she had joined her flock.  Then one morning at daybreak, there she was, waiting patiently on the cyclone fence. 

—Journal entry:   April 17—awoke this morning to see the lame thrush waiting patiently on the fence.

With the threat of snow having passed, food was no longer scarce.  The woods were alive with insects, and there was always plenty of seed in the feeders.  There were also bread scraps left for the raccoons, and that she sometimes indulged.  But what she loved most were peanuts; treats meant for the jays and squirrels.  For weeks, she watched them take handouts, and it made her curious.  Gradually, she became less fearful; after all, she’d seen the jays and squirrels do this dozens of times.

With cautious sidesteps, she took a peanut.  Although virtually weightless, she found it awkward, and had to flap her wings faster to clear the fence; that’s right, she flew over the fence, not through it.  She made a beeline to South Bank where she found a cedar stump from which there grew a small hemlock that sheltered her from the watchful eyes of the jays and crows.  Clearly, she was smarter than we gave her credit.

—Journal entry:  April 18—of all the varied thrushes to fill our woods with song, the lame female is the smartest of them all; not only does she fly over the fence instead of through it, but she is the only thrush we’ve ever seen that begs for a handout.

Unlike chickadees that hold a seed between their feet to open it, she lacked this ability, regardless of her lame foot.  Her beak, better designed for eating insects and fruit, she used like a dagger, lunging forward, jabbing the shell until it cracked.  In time, she got quite good, and could open them with just a few quick jabs. 

—Journal entry:  April 28—although the flock has gone, and has left her without a mate, her heart is full of song.  Maybe she will rejoin the flock, maybe she will find a mate, but until that time, we’re happy she’s with us.

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Copyright 2012.  All rights reserved.

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Additional reading▼

🌿Where the birds are:  eBird http://ebird.org/content/ebird/

🌿Birding basics visit:  http://www.allaboutbirds.org/Page.aspx?pid=1200