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The eastern gray treefrog is one of many performers in nightly summer concerts.

The eastern gray treefrog is one of many performers at nightly summer concerts.

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One of my favorite things about summer is the free outdoor concerts. I’m not talking about local bands that occasionally perform from the park gazebo even though they can be a pleasant accompaniment to my evening dog walk. No, nothing says summer like the insect-amphibian jam sessions that take place almost every evening.
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I’ve moved quite a lot in my life and have been delighted to learn that each place I’ve lived long enough to grow accustomed to—six U.S. states and a Scandinavian country—has a timbre and cadence all its own, distinctive to that specific habitat in a certain continent on a singular planet in an expanding universe. It’s the soundtrack of home, wherever home may be at that particular time in field cricket 2 by Jimmy Smith, CCLone’s life.
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The musicians start warming up as the light begins to fade. They’ve been playing the same basic tune since I was a child so I immediately recognize the overture. By 7:00-7:30p the instruments are tuned and ready to swing.
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Field crickets (Gryllus spp.) establish the beat with their forewings, kind of like a finger-snap that varies from cool to hot depending on the atmosphere.
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Common true katydids (Pterophylla camellifolia) shift the accent…
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common meadow katydid by Rachid H, CCL… and the common meadow katydids (Orchelimum vulgare, not as common as the name implies) chime in with a bit of lawn-sprinkler syncopation.

 [you might need to boost the volume a bit on this one]

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Before long, the dog-day cicadas (Tibicen canicularis) are stealing the show.
dog-day cicada by Roger Engberg, CCL
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As the evening progresses, though, the cicadas and other insects cede the stage to the second act—the frogs and toads… possibly because these headliners have been known to devour the opening act!
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The band is made up primarily of horns and percussion. This isn’t jazz—there’s not much in the way of improvisation and the musicians don’t really take turns letting one another shine during a solo. It can be difficult to identify the featured players, in part because the cast keeps changing; there are fair-weather performers, some northern cricket frog by Andy Reago and Chrissy McClarren, CCLhave stormy temperament, and others don’t like to travel far from their favorite watering hole. Still, there are some easily recognized voices.
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Northern cricket frogs (Acris crepitant) step in to set the pace abandoned by their namesake insect. I’ve seen their call described as pebbles bouncing against one another but to me it’s a metal cabana—chain wrapped around a wood cylinder and shaken, not stirred.
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The American toad (Anaxyrus americanus) is a minimalist; not much complexity but the sustain on that single trilling note is impressive.
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green frog by Matt Reinbold, CCLThe green frog (Lithobates clamitans), on the other hand, is a true traditionalist—no electric bass for this fellow, or even an upright acoustic. Listen carefully and you’ll hear his homage to a single string and washtub.
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Tiny boreal chorus frogs (Pseudacris maculata) play plastic comb call-and-response…
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eastern gray treefrog by USFWSmidwest, CCL… and the gray treefrogs (Hyla versicolor) are in charge of the upper register. These little guys can blow, plus how about that vibrato!
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When the gang’s all here and lettin’ it rip the result is more cacophony than symphony—not everyone’s ideal night music but a lullaby to my ears.
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© 2015 Next-Door Nature—no reprints without written permission from the author (I’d love for you to share my work  but please ask). Thanks to these photographers for making their work available through a Creative Commons license (CCL) or Project Guttenberg License (PGL) (from top to bottom):  USFWSmidwest (eastern gray treefrog); Jimmy Smith (field cricket); Lisa Brown (common true katydid); Rachid H (common meadow katydid); Roger Engberg (dog-day cicada); Andy Reago & Chrissy McClarren (northern cricket frog); AllieKF (American toad); Matt Reinbold (green frog); J. N. Stuart (boreal chorus frog); USFWSmidwest (eastern gray treefrog). 

 

Male downy woodpecker (Picoides pubescens)

The male downy woodpecker is a dapper urban resident (iStock, used with permission)

Rushing out the door, I went over the list in my head. Workout pants and layered tees—check. Running shoes—check. Coat, hat, gloves—check. Keys and sunglasses—check. MP3 player—check. Everything was in order as I pulled out of the driveway.

Or so I thought.

Fifteen minutes later I pulled into a parking space at the Power Valley Conservation Nature Center, a 112-acre oasis in suburban St. Louis created by the Missouri Department of Conservation with hilly trails perfect for raising my heart rate for 30-40 minutes. But as I stepped out of the car and began to gather my gear I realized with dismay I’d left behind a critical component—my earbuds.

The thought of a run without my workout mix, and without any caffeine in my system either, was disheartening. I need the motivation of a musical pulse. But I didn’t have time to go back to the house so I set off anyway, prepared to suffer.

About 10 minutes later I realized I was running to a faint drumbeat. At first I thought someone who had NOT forgotten their audio equipment had the volume on their iPod turned up to 11. Once I realized the thumping came from the woods themselves, though, it wasn’t too long before I spotted the drummer, dressed more appropriately for jazz than heavy metal in the stylish black-and-white houndstooth jacket and jaunty red cap of a male downy woodpecker. In spite of the bird’s diminutive size—no more than 6” from head to tail-tip and weighing in at an ounce or less—his wardrobe set him apart on that overcast day from the slate-and-silver hickory bark backdrop.

Downy’s are capable of making a noise disproportionate to their size. When a woodpecker is looking for a mate or claiming a territory, the sound of drumming needs to carry; building a nursery cavity using a beak as a jackhammer isn’t quiet either. But if you’re in the woods and the beat is more bongo than bass, hunger is probably acting as the drummer’s muse. A gentle tap, tap, tap betrays hollow spots beneath the bark where wood-boring insect larvae wait.

drawing of a woodpecker's tongue

Woodpeckers can really stick out their tongues (Florida Center for Instructional Technology, used with permission)

Once dinner has been detected, things get… interesting. That short chisel of a beak hardly prepares you for what’s inside—like many other woodpeckers, the downy has a barbed, sticky, and flexible tongue so long it wraps around the skull when at rest. If ever there was a bird ready-made for rock ‘n roll, it’s the woodpecker. Gene Simmons got nothin’ on these headbangers.

The whole tone of my morning changed in an instant. It’s so easy to carry a personal soundtrack wherever I go that I forget about everything I normally tune out when I turn up the volume. As a result of my oversight, I suddenly had a standing-room-only ticket to a great live performance, one I would surely have missed had this excursion proceeded according to plan.  My run could wait. I stayed for several encores and gave that downy an enthusiastic round of applause as he flew off toward his next gig.

[This post was originally published in January 2011. Hope to have a new installment ready for prime-time soon.]

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love-earthThis blog, like so many activities that foster support and appreciation of the natural world, is a labor of love. If you’ve enjoyed learning about the creatures who share our built environment, consider becoming an NDN Benefactor with a donation of any amount you’re inspired to give. If you’d like to find a little Next-Door Nature surprise in your inbox just click the Subscribe!  button in the upper right-hand corner of this page and receive notifications of new posts!

© 2011 Next-Door Nature— no reprints without written permission from the author
red-bellied woodpecker on fence (Photo: Brian Peterson, Creative Commons license)

Robert Frost said, “Good fences make good neighbors” but embattled red-bellied woodpeckers must find other ways to protect their territories. (Photo: Brian Peterson, Creative Commons license)

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Last Sunday morning I unexpectedly found myself sitting ringside for a brief but furious brawl. Two male red-bellied woodpeckers (Melanerpes carolinus) were having a boundary dispute that started with an argument over some shrubbery then escalated into a full-on aerial assault. Colliding mid-air, they grasped one another by the feet and were so intent on punching, pecking, and plucking, the adversaries flew thoughtlessly over the nearby road directly in front of my car. Luckily, I was making my way slowly along the otherwise quiet suburban street, so I was able to stop and watch.

With my windshield serving as an impromptu HDTV, the smackdown aired for all of 45 thrilling seconds and then, as if in response to a referee’s break command… it was all over.  Each fighter retreated, shouting insults over his shoulder as he returned to his corner.

male and female RBW by Jason Paluck, Creative Commons licenseRed-bellied woodpeckers (let’s just shorten that to RBWs, shall we?) are a medium-sized bird—just over 9” (24 cm) from chisel beak to stiff tail tips with a 13-16” (33-42 cm) wingspan. Like many North American woodpeckers, they wear a black-and-white houndstooth jacket, but their bright red Mohawk (males sport a full forehead-to-neck cap while females wear an abbreviated version) sets them apart. It’s also the reason these birds are so often misidentified as the similar-sized red-headed woodpecker (Melanerpes erythrocephalus), although once the difference is pointed out the mistake is rarely repeated. RBWs take their name from a subtle scarlet stain on their buffy belly.

red-headed vs. red-bellied woodpeckers by Laura Gooch and Jason Paluck, respectively (Creative Commons license)Year-round residents in U.S. wetlands, river bottoms, woods, and wooded suburbs from the Midwest east to the Atlantic coast, RBWs are omnivorous, consuming all manner of  insects, nuts, seeds, sap, and fruit. They store surplus food in various nooks and crannies and, since they don’t migrate, their larders come in handy during winter. This species employs gender-specific foraging strategies—males search for sustenance primarily along bole while females spend the bulk of their time on the boughs.

Biologists don’t often venture out on a limb to officially identify any non-human behavior as play, but I’ve notice the profession has loosened up a bit on this issue over the past decade or so, thankfully. One example of this trend was a description of RBW behavior I read recently. This species will periodically engage in swift, nimble, and unpredictable forest flights, complete with many direction changes to dodge trees, and accompanied by constant excited chatter. The author of this resource was quick to explain that the activity probably has a practical application in that it helps youngsters practice evasive maneuvers that would come in handy should predators be lurking about. However, and surprisingly, the expert also admitted the birds seemed to be having fun.

male red-bellied woodpecker in nest (Photo- Frederick Knapp, Creative Commons license)RBWs are monogamous—for the extent of a breeding season, that is (so perhaps it would be more accurate to say they are serial monogamists)—and both are actively involved in raising young.  They nest in hardwood and pine trees, along with the occasional fence post, by excavating a cavity or stealing one from other birds. What goes around comes around, though—or so says a timeworn adage; RBWs often lose their precious nest holes, in turn, to European (aka common) starlings (Sturnus vulgaris).

Assuming the pair can hang on to their home, the female lays two to six white eggs on a cushion of wood chip construction debris and incubates them for 12 days. The hatchlings are altricial, meaning they begin their lives naked, blind, and helpless. They don’t waste any time growing up, and are ready to leave the nest for a first tentative flight when they are 24—27 days old. Depending on the region, the adults may raise from one to three broods in a season.

red-bellied woodpecker at feeder (Photo: ehpien, Creative Commons license)Defending the homestead is a top priority during the child-rearing seasons, especially if the ‘hood includes a well-tended feeder (a gold mine for species able to digest seeds or suet). Even though most bird nestlings can’t tolerate seeds and need a diet composed largely of insects, when Mom and Dad can grab a high-calorie meal from the avian equivalent of a fast-food restaurant, they have extra time to hunt for the more illusive foods their offspring need to develop properly.

Since RBW territories range from 3 to 39 acres protecting the perimeter is far from a simple task, especially when feeding yourself and your family is a full-time job. So, naturally, breaches occur… but everyone trespasses and is trespassed against.  Border skirmishes are common but they rarely result in bloodshed. Research tells us that’s due, in part, to the fact that the intensity of defense behavior tends to decrease as an animal moves away from the center of its territory. Put another way, property rights become less important the farther you are from home. In most cases, both combatants throw in the towel long before there’s a knock-out.

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There’s nothing quite like finding a little Next-Door Nature in your email inbox—click the “subscribe”  link in the upper right-hand corner of this page and receive notifications of new posts!
© 2012 Next-Door Nature—no reprints without written permission from the author (I’d love for you to share my work; all you have to do is ask). Thanks to these photographers for making their work available through a Creative Commons license: [starting from the top] Brian Peterson (on the fence); Jason Paluck (male & female; red-bellied); Laura Gooch (red-headed); Frederic Knapp (in nest); ehpien (rbw @ feeder).
common brushtail possum (Photo: David Midgley, Creative Commons license)

Common brushtail possums know how to work the cute (Photo: David Midgley, Creative Commons license)

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Consider, if you will, the sartorial importance of tail attire.  To bare, or not to bare… that is the question.  The answer might seem to be of little consequence, but for marsupials living in cities and suburbs some strategically placed fur can make all the difference.

That’s because naked tails make people nervous. I blame this bias on the Black Death. Of course, now we know the true culprit in that famous pandemic of 1347 was not the rat, but the infected fleas that hitched a ride on those hapless rodents. Since standards of human hygiene at the time were rather… haphazard, shall we say, there were plenty of opportunities for the insects to hop onto a handy human. We may not remember why rodents make us uneasy but the bias remains to this day.

How else do you square our acceptance and even advocacy of squirrels and chipmunks, for example, with our abhorrence of rats and mice? As Carrie Bradshaw of Sex and the City fame so wisely observed, “A squirrel is just a rat with a cuter outfit.” Clothes make the man and the mammal.

The same could be said of the common brushtail possum (Trichosurus vulpecula) and its cousin the Virginia opossum (Didelphis virginiana). Both are omnivorous marsupials of similar size and weight. However, the former has a hirsute terminus while the latter’s prehensile appendage is as furless as a snake. Brushtails are the source of much frustration among Aussie homeowners who, nonetheless, demonstrate great fondness for this plush-toy wannabe. The North American model does not enjoy a similar degree of affection from its human neighbors (to put it mildly).

Is this inequity mere coincidence? I think not—if you ask me it’s blatant bare-tail bigotry!

Personally, I find the adult Virginia opossum to be a handsome creature and their young ones winsome and endearing.  But—let’s face it—we only have one marsupial here in the U.S., so there’s no competition for best in show.

It’s a different story in Australia, where possums* and the closely related gliders account for approximately 30 of the continent’s 140 marsupial species. Brushtails are attractive animals by any aesthetic standard, with thick, luxurious fur that ranges in color from silver-gray to cream, brown, black, and even red, depending on the subspecies.

As the name implies, the common brushtail is a familiar resident along much of coastal Australia including the major metropolitan areas such as Sydney, Melbourne, Brisbane, and Perth. Suited to a wide variety of habitats, from rainforests to semiarid regions, this semi-arboreal (tree-dwelling) possum has adapted readily to urban life, trading traditional tree cavities for a home under the eaves.

brushtail mother and child (Photo: mugley, Creative Commons license)Brushtails can breed at any time during the year, but there are two peak seasons—from September to November (southern hemisphere spring) and from March to May (Australian autumn). Following a 16-18 day gestation, the female gives birth to a single blind and extremely underdeveloped child who scrambles unaided up to her pouch. Once inside, it will attach to a teat and remain there for another four or five months, after which it will either stay home at the den while Mom goes out to forage or ride along on her back, sharing any groceries she finds while learning what and where to eat. Male possums are not involved in child-rearing.

Human or non-human—if you want to succeed in the urban jungle, it sure doesn’t hurt to have a pretty face. Brushtails have large ears perched on a rounded head, a pink nose and dark liquid eyes… and they don’t seem at all shy about working their assets to full advantage. They may have learned a thing or two from eastern gray squirrels (Sciurus carolinensis), introduced to Australia sometime between 1900 and the 1930s—there’s just something about watching a furry creature nosh while holding the treat with two hands that people find irresistible, apparently, because hand-feeding fruit treats is a popular past-time.

attic brushtail (Photo: play4smee, Creative Commons license)There’s a down side to this Down Under hospitality, though. With warm, dry sleeping berths and plenty to eat, brushtails haven’t found it necessary to step lightly on the Earth… or in the attic either.  Their heavy-footed nocturnal comings and goings and loud vocalizations are responsible for plenty of sleepless nights and lost tempers. Brushtails often wake the neighborhood dogs as they wander through the neighborhood via utility poles and fencing, creating the same kind of hard feelings directed at Virginia opossums on the other side of the globe, for the exact same reason.

When not snacking on handouts from the produce section they will munch on magnolias, roses, and other selections from the flower garden as well as on eucalyptus and other trees—Aussies do not consider this one of the brushtail’s more appealing qualities. And, like their northern hemisphere kin, brushtails will dumpster dive and help themselves to the back porch pet food smorgasbord, resulting in much hair-pulling and teeth-gnashing by Homo sapiens.

Yet, somehow, brushtails seem largely immune to the vilification of their less charismatic cousins. To the cute (and furry-tailed) go the spoils, I guess—it’s an all too familiar tail and decidedly unjust. But as my mother (and probably yours too) always said, “Who told you life is fair?”

One thing’s for sure, it wasn’t a ‘possum.

[This one is for Barb at Passionate About Pets and People. Thanks for your support and encouragement!]

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* Although both are marsupials, it is commonly accepted that the Americas have opossums (colloquially referred to as ‘possums) while Australia has possums. Yes, it is confusing. No, I don’t know why or how this came to be. Even in the 21st Century there remain great unsolved mysteries.

Start your day with a little Next-Door Nature—click the “subscribe”  link in the upper right-hand corner of this page and receive notifications of new posts!
© 2012 Next-Door Nature—no reprints without written permission from the author (I’d love for you to share my work. Just ask.). Thanks to these photographers for making their work available through a Creative Commons license: David Midgley (brushtail eating an orange); mugley (mother and baby); and play4smee (attic brushtail).
eastern bluebird 2 by Jason Matthews, Creative Commons license

A male Eastern bluebird personifies happiness, whether he’s happy about it or not (Photo: Jason Matthews, Creative Commons license)

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Happiness is a shy little bird. Hiding from sight in life’s nooks and crannies, impossible to find if you look but then it darts out and lands on your shoulder just when you least expect it. It sidles up beside you like a pickpocket on a crowded street, soft and silent as wings brushing against your lapel. Hardly even noticed until something or someone causes it to flush in a flurry of feathers from beneath your jacket, taking with it a sizeable chunk of your heart. Try to grab hold as it flies away and the thief proves as elusive as dreams upon waking, slipping through your fingers like a shadow, like quicksilver.

The concept of happiness has been flitting in and out of my brain and my life for a couple of weeks now. My birthday earlier this month may have provided the initial impulse. This wasn’t a major milestone year, I’ve got too much on my plate these days to leave much room for cake, plus I’m living in a new town and don’t know many people yet… but I did take a little time to acknowledge the day and do some thinking. December 31st may be the culturally accepted time to contemplate one’s short- or long-term past and make plans for the year to come, but my inner-Pagan knows the vernal equinox is the true start of a new trip around the sun. Besides, I’m not much for following the crowd. I was the kind of kid who would disassemble all the board games in the house, shuffling the tokens and cards to make up my own game with my own rules.  So I like the idea of a personal calendar that begins in April, and a personal New Year’s Eve for reviewing said year is also appealing. Later that same week, two unanticipated events provided additional incentive to ponder the nature of happiness.

Then again, maybe I’ve had happiness on my mind because the bluebirds have returned.

mountain bluebird pair (Photo: freeopinions, creative commons license)

Mountain bluebird pair

This year, I’ve been watching eastern bluebirds (Sialia sialis) each morning while my terrier-boy practices his soccer moves on a squeaky red rubber ball. At other times in my life, while living in other parts of the U.S., I’ve watched spring come to town on the wings of both western and mountain bluebirds (S. Mexicana and S. currucoides, respectively).  A feathered piece of sky flashing across the landscape on shallow wing beats can lift a heavy heart and lighten my mood.

Members of the Turdidae family (aka thrushes), bluebirds are related to that other famous spring harbinger, the American robin (Turdus migratorius). All three Sialia species are easy to spot and identify even though, as fruit and insect eaters, they don’t visit seed-filled feeders. The males are clad in some combination of blue with red and/or white; their mates wear less conspicuous versions of the same plumage.

Efforts to ensure this popular bird’s continued breeding success began with the recognition that they were struggling in the face of competition from introduced species such as the European starling (Sturnus vulgaris) and house sparrow (Passer domesticus), as well as reduced access to nesting habitat. Happily, by building, installing, monitoring, and maintaining special nest boxes, handy men and women across the U.S. have proven crucial to the species’ recovery.

Bluebirds have long symbolized cheerfulness, health, prosperity, and renewal, although I’m not sure why. Their lives are far from easy or free of conflict. Males battle over breeding territories, chasing one another at breakneck speeds, grabbing each other by the feet in mid-air, smacking opponents with their wings as they try to pull each others feathers out with their beaks. They must defend nest cavities or boxes from a host of other birds, many of which are substantially larger. Once a nest site has been established, a mated pair may produce 2-4 broods per season—a task that requires foraging non-stop during daylight hours to find enough food to keep themselves and their offspring fed. If that were not challenge enough, bluebirds undertake an exhausting and hazardous migration of up to 2,000 miles each autumn and spring.

female eastern bluebird by Patrick Coin, Creative Commons license

Female Eastern bluebird

Despite these hardships, some sources claim the connection between blue birds and happiness is global (albeit focused on bird species indigenous to each country or continent). One thing is certain—the notion, however it began, has been perpetuated by Hollywood and on the radio. I have to wonder if any other bird has been as popular with songwriters and singers, starting with  Bluebird of Happiness, a hit song in the early 1930s that may have ushered this phrase into the popular vernacular.  Judy Garland probably helped things along when she sang of bluebirds flying Somewhere Over the Rainbow. For those who like both their birds and their grass blue, there’s Lester Flatt’s Bluebirds Singing For Me. Paul McCartney, Buffalo Springfield, Bonnie Raitt and, more recently Christina Perri and Adam Green all feature bluebirds on their playlist. Sara Bareilles’ poignant Bluebird tells of a kind of migration, but my own favorite blue bird tune, Birdhouse in Your Soul by They Might Be Giants, transports me to a happy scene, sitting at the kitchen table of a remote lake house in a faraway forest.

Emotions can be tricky to articulate and color can help paint a clearer picture. I get that. If a friend says she’s in the pink or he’s green with envy, you know the score even without the details (although you may still want to hear them). Red is, of course, the color of both anger and passion (maybe that’s why one so often leads to the other). Blue is happiness—at least, that’s what a little bird told me. But is it? If I say I’m feeling blue you’re not likely to picture me in your mind’s eye singing in the rain ala Gene Kelly.

western bluebirds by Julio Mulero, Creative Commons license

Western bluebirds

How did a single color come to represent both sides of the spectrum, sadness and joy? I wish I knew, but I’m not sure it matters in the long run. I do know this: happiness prefers an open palm to an iron grip. It doesn’t do well when caged; like a wild bird, it needs to be free to come and go as it chooses. A full life requires both kinds of blue plus all the other colors and creatures, winter and spring, parting and reunion. If you want to have happiness in your life you must be willing to risk losing it, trusting that it will return as surely as bluebirds in April. That’s the trade-off, the price you pay for the flutter of wings in your heart and stomach.

But worth every penny.

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There’s nothing quite like finding a little Next-Door Nature in your email inbox—click the “subscribe”  link in the upper right-hand corner of this page and receive notifications of new posts!
© 2012 Next-Door Nature—no reprints without written permission from the author (I’d love for you to share my work; all you have to do is ask). Thanks to these photographers for making their work available through a Creative Commons license: Jason Matthews (male Eastern bluebird);  freeopinions (mountain bluebirds); Patrick Coin (female Eastern bluebird); Julio Mulero (Western bluebirds).
black-and-white warbler (Photo: Friends of Mount Auburn, Creative Commons license)

Black-and-white warblers are just one of hundreds of species and millions of individual birds currently making their way southward… and running into some major obstacles (Photo: Sandy Selesky, Creative Commons license)

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I’ve never been much for following trends and this week was no exception. I’m writing from an altitude of 10,000+ feet and, as I fly west-to-east across North America on my way home from a conference in Fort Collins, Colorado, millions of birds are winging from south-to-north along time-honored sky routes.

warbling vireo (Photo: Eric Bégin, Creative Commons license)

Warbling vireo, warbling

Spending time west of the Mississippi flyway provided me with a chance to get reacquainted with some favorite species from when I lived in New Mexico. I got a heads-up on who to look for using a great resource—the e-Bird Migration Forecast. For example, the pace of this record-breaking early return of migratory birds is expected to slow somewhat during the last gasp of March due to unfavorable winds, but Bell’s and warbling vireos (Vireo bellii and Vireo gilvus, respectively) began to arrive out West a couple of weeks ago. By the time I get back home to the southeast there’s a good chance any number of wood-warblers will already be there including one of the more easy-to-identify species, the black-and-white warbler (Mniotilta varia). e-Bird’s experts predict it shouldn’t be too long before blue-gray gnatcatchers (Polioptila caerulea) come to my neighborhood since they’ve been spotted as far north as Maryland already.

Sadly, one of the best places to see a diverse array of migratory birds is at the base of tall buildings. This is also one of the worst places because the birds you’ll find are likely to be dead or injured. Others are simply too exhausted to fly any further which makes them very vulnerable to the scavenging species who have learned that migration season in the city means food is literally falling from the sky. One expert estimates as many as 100 million birds die in collisions with buildings every year. Songbirds are particularly susceptible to this hazard.

At night, migrating birds seem to be strongly attracted to artificial light and once inside the neon and fluorescent glow they’re reluctant to return to the darkness. High-rise glass and light are a deadly combination for these travelers—those that don’t collide with the buildings fly around and around as if caught in a sci-fi tractor beam until they drop from fatigue.

blue-gray gnatcatcher (Photo: Jerry Oldenettel, Creative Commons license)

Blue-gray gnatcatcher

In some cities, bird-loving volunteers organize rescue teams who arrive before sunrise to beat gulls, free-roaming cats, raccoons, coyotes, and others to the survivors. The injured are transported to wildlife rehabilitators for care, the dead are collected and counted.  The Chicago Bird Collision Monitors have reported finding an average of 5,000 birds on the streets and sidewalks during the annual spring and fall migrations. In Toronto alone the Fatal Light Awareness Program (FLAP) has documented bird-building collisions for over 140 species.

No one wants to add to his or her birding life list this way.

Thankfully, FLAP has some simple suggestions for reducing the carnage:

  • Turn off the office lights and close the blinds when you leave at the end of the day, and ask your co-workers to do the same.
  • Talk to the building’s maintenance supervisor and cleaning staff to explain their critical role in creating a bird-friendly building.
  • If you notice dead and/or injured birds on the ground around your building, consider organizing a group of coworkers to serve as rescuers and team with wildlife rehabilitators in your area.
  • FLAP recommends keeping a supply of paper grocery bags on hand for rescues. Once a bird has been placed inside the top can be folded over and stapled shut. This does not create an air-tight seal so there’s no need to poke air holes in the bag, and the darkness inside the bag will help calm the bird so it doesn’t injure itself further.

Before you forget, why not leave a reminder on your computer screen or near your office door? If you make it just a little harder to see migratory birds in the urban jungle you may end up making it just a little easier to continue seeing migratory birds in the future.

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Start your day with a little Next-Door Nature—click the “subscribe”  link in the upper right-hand corner of this page and receive notifications of new posts!
© 2012 Next-Door Nature—no reprints without written permission from the author (I’d love for you to share my work. Just ask.). Thanks to these photographers for making their work available through a Creative Commons license: Sandy Selesky, Friends of Mount Auburn (black-and-white warbler); Eric Bégin (warbling vireo);   Jerry Oldenettel (blue-gray gnatcatcher); and Joe Penniston (downtown Chicago at night).
Cedar waxwing (Photo: Eve Fraser-Corp, Creative Commons license)

By the end of winter, the fruit upon which cedar waxwings depend can pack a real punch (Photo: Eve Fraser-Corp, Creative Commons license)

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I recently came across a report that cedar waxwings (Bombycilla cedrorum) have returned to Texas. Every time I hear someone mention this species I’m reminded of  my days as director of a wildlife center in Houston. For a few weeks every year the waxwings would show up by the cardboard box-full and the rehabilitation clinic would turn into… well, a different kind of rehab center.

With their handsome, distinctive plumage, even a newbie birder can easily recognize this species. Their yellow tail- and red wing-tips look as if they’ve been dipped in sealing wax—thus the name. With a range that covers much of North America, waxwings aren’t rare but they’re not as common as some of our iconic backyard birds, so it’s always a bit of a thrill when they’re in the neighborhood.

Cedar waxwing and chick (Photo: Alan Huett, Creative Commons license)They’re one of only a handful of avian species in the U.S. and Canada whose diet is composed largely (but not entirely) of fruit, a useful characteristic when one shares a breeding territory with brown-headed cowbirds (Molothrus ater) and other nesting parasites—females who don’t bother to build a nest of their own. Instead, they leave their eggs in the nests of other birds and the cowbird chicks are cared for like biological children. In fact, the foster nestling normally out-competes the surrogate’s own offspring when food is being passed out but the high-sugar diet provided by waxwing parents, while perfect for their own kids, causes the cowbird to waste away.

Waxwing adaptability has allowed them to benefit from the introduction of non-native fruit-bearing plants used in urban and suburban landscaping. For example, they seem to love honeysuckle… and it shows. The red pigment in the exotic vine’s berries can turn the bird’s canary tail-tips bright orange, a plumage change birders and ornithologists first began to notice in the 1960s.

Waxwing flock on pyracantha (Photo: Bob Muller, Creative Commons license)Waxwings travel in flocks that may include 40+ individuals, all searching for pyracantha and privet, choke cherries, mulberries, and any other tree or shrub that bears sugary fruit. Once they’ve gobbled up every last berry, they move along without a backward glance.

Unless the fruit is spiked.

It’s not a matter of someone trying to contribute to avian delinquency. From late autumn until plants have produced new spring and summer crops, last season’s berries, drupes, drupelets, pomes, and other sweet seed containers hang on, growing inceasingly less… fresh, shall we say. Temperature fluctuations and the presence of wild yeasts often will cause fruit to ferment in situ. Migration and colder temperatures make for voracious birds and the waxwings are carbo-loading as fast as they can swallow. They don’t seem to notice some of the snacks pack a punch. When you weigh slightly more than an ounce, the alcohol content doesn’t have to be very high to knock you for a loop. Next thing you know, birds are careening around on the front lawn like New Year’s Eve.

Injured waxwing (Photo: Churl Han, Creative Commons license)It can look rather comical but it’s no laughing matter. Many inebriated birds are seriously injured or are killed when they fly into cars and windows.

Good Samaritans across the county scoop disoriented birds into cardboard boxes and head for the nearest wildlife rehabilitation center. There, the birds are given a head-to-toe, beak-to-tail examination. Most of the patients are simply allowed to safely sleep it off in a warm, dark room before being released to continue their travels… although they probably set out with a doozy of a headache.


Start your day with a little Next-Door Nature—click the “subscribe”  link in the upper right-hand corner of this page and receive notifications of new posts!
© 2012 Next-Door Nature—no reprints without written permission from the author (I’d love for you to share my work; all you have to do is ask). Thanks to name for making their work available through a Creative Commons license: Eve Fraser-Corp (waxwing with wizened berry); Eve Fraser-Corp (waxwing with wizened berry); Alan Huett (waxwing adult and nestling);  Bob Muller (waxwings on pyracantha)’ and Churl Han (injured waxwing).

white-crowned sparrow by KaCey97007, Creative Commons license

A white-crowned sparrow trying to get a date (Photo: KaCey97007, Creative Commons license)

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seagull (Photo: Dani_vr, Creative Commons license)How can one small voice cut through the cacophony of modern metropolitan life? A recently published study, combined with some earlier work, suggests that contrary to what you might assume, the secret to city communication isn’t shouting.

Urban background noise is heavily weighted toward the lower sound frequencies of 20 to 200 Hz—think diesel engines (50-60 Hz).  That’s not to say there aren’t a lot of higher frequency noises in the concrete jungle but, compared to say, the rain forest’s tenor voice, cities sing baritone… and with enough projection to reach the last row of the balcony. Depending on the location and the time of day, your city may be belting out it’s theme song at anywhere from ~45-90 decibels (dB). Ever try to tweet over a lawn mower (and I don’t mean with your smart phone)?

People who haven’t yet experienced any hearing loss can detect activity in the 20 to 20,000Hz range. The faintest sounds we’re likely to hear register at about 0 dB. By 120 db we begin to experience discomfort or even pain. Now, as someone who loves to listen to nearly every kind of music, laughter in all its forms, Japanese prayer bells playing with a breeze, and rain bouncing on a tin roof, I’d be the first to agree that the human ear is a marvel. But compared to many of our fellow Earthlings, it’s… well, it’s pitiful. My wire fox terrier puts me to shame, easily picking up sounds from 40-60,000 Hz. The super-sensitive hearing of a bat, used for echolocation, ranges from 20-120,000 Hz.

common blackbird (Photo: Oystercatcher, Creative Commons license)

common blackbird

According to the ever-useful Birder’s Handbook, we have more auditory commonality with birds, whose ability to discriminate between frequencies and degrees of loudness is on a par with our own. So perhaps we would be well served to take a page from the songbird songbook when trying to be heard in our rapidly urbanizing modern life. Researchers at the Universities of Copenhagen and Aberystwyth found that great tits (Parus major) living in urban habitats sing at a significantly higher frequency than their rural relatives. This finding coincides with previous studies reporting the same phenomenon for house finches (Carpodacus mexicanus), song sparrows (Melospiza melodia), white-crowned sparrows (Zonotrichia leucophrys), dark-eyed juncos (Junco hyemalis), and common blackbirds (Turdus merula).

European robin (Photo-Steve Harris, Creative Commons license)

European robin

Of course, going all Bee-Gees isn’t the only way a guy can get some attention from the talent scouts.  A 2007 study from the University of Sheffield found that European robins (Erithacus rubecula) living downtown changed their performance times, from doo-wopping during the day to crooning almost exclusively after sundown when the din dies down a bit. In Berlin, nightingales (Luscinia megarhynchos) take the less subtle approach and just turn up the volume, at least on weekdays. But there’s a price to be paid for setting the amps to 11—a greater metabolic demand and more attention from predators. By broadcasting on a different frequency, some city songbirds have stumbled onto a low-risk solution to a major challenge of city life.

song sparrow (Photo: TC Davis, Creative Commons license)

song sparrow

There’s incentive for avian adaptation (let’s not call it selling out) to make it onto the airwaves. You see, in the bird world the divas are all, um… divos. No, they don’t wear red plastic wedding cake hats and ill-fitting 1980s MTV fashion—that’s Devo. Let me put it another way: boy birds are the rock stars, girl birds are the groupies. Males warble (or learn to shred the guitar, or maybe groove a bass line) to get noticed by the ladies. If a gal likes a guy’s song she’ll hook up with him and probably become his baby-mama. But there’s a lot of competition out there and before you can score, you’ve gotta get heard.

Hey, singing falsetto to some chick may not be the most macho thing a fellow can do, but it beats spending Saturday night getting drunk at the karaoke bar with your buddies and going home alone.

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Start your day with a little Next-Door Nature—click the “subscribe”  link in the upper right-hand corner of this page and receive notifications of new posts!
© 2012 Next-Door Nature—no reprints without written permission from the author (I’d love for you to share my work; all you have to do is ask). Thanks to these photographers for making their work available through a Creative Commons license:  KaCey97007 (white-crowned sparrow); Dani_vr (seagull); Oystercatcher (common blackbird); Steve Harris (European robin); and TC Davis (song sparrow).

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