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The British may have lost North America but their native house sparrows have successfully colonized the continent.

The British lost North America but English house sparrows have colonized the continent.

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It seems to happen once each century. In 1775 the Redcoats showed up in Boston, the Beatles made a big splash about 200 years later in 1964, and in the sweet-spot in-between the House Sparrows (Passer domestics) arrived.
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It’s difficult to believe, given current controversies and political grandstanding, but for a long time America had a very open-door immigration policy that allowed almost anyone—human and non-human—hassle-free entry. For example, no one batted an eye when my paternal ancestors washed up here after being kicked out of Scotland during the Highland Clearance to make room for sheep… but I digress. In the 1850s, when Brooklyn Institute Director Nicholas Pike purchased 8 pairs of house sparrows from England he didn’t have to sneak the birds past a Customs agent—the Animal and Plant Health Inspection Service (APHIS) hadn’t been created yet and wouldn’t be for over 100 years. Nor did Pike need permission from the New York Department of Environmental Conservation to release the birds. It didn’t exist.
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Introducing these Old World sparrows to North America was not done on a whim. Some sources suggest the birds were imported to control a serious canker-worm (Alsophila pometaria or Paleacrita vernata) infestation threatening New York City’s trees—a somewhat misguided notion since house sparrows are granivores (seed-eaters), not insectivores, although they do feed insects to their nestlings.  Pike reportedly paid $200 for the pairs’ passage across the Atlantic, which may not sound like much but according to one relative-value calculator it’s equivalent to $5,000 today.
.feeding the sparrows
Like many immigrants before them those first settlers didn’t do all that well in their new home. Not dissuaded, Pike purchased another 25 pairs the following year and released them along the East River. This cohort proved hardier, or perhaps more adaptable. Another 100 pairs were ordered in 1853 and released at the Greenwood Cemetery, Central Park, Union Square Park, and Madison Square Park. Americans have a history of Anglophilia so it should come as no surprise that soon the former colonies were all a-twitter about these chatty, cheerfully social birds.
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male house sparrow by Eric Bégin, CCLHouse sparrows aren’t closely related to native North American sparrows and you can see it in their physique—they’re a bit heavier, with a deeper chest, a more rounded head, shorter tail, and a less delicate bill. Six inches (15 cm) long from beak to tail-tip, and weighing in at about 1.4 oz (40 g), the male house sparrow cuts a dashing but not flashy figure; he’s British, don’t forget, and all business. Bright blues, greens, and yellows are not his cup of tea; rather, he wears a neutral palette of black, gray, and chestnut, with a touch of white to sharpen up the entire female house sparrow2ensemble. Female fashion preferences are appropriately tweedy: tawny-brown with darker striping on top, oatmeal-tan or gray below. More Anthony Hopkins and Emma Thompson than David Bowie and Amy Winehouse, nonetheless, house sparrows were a trending novelty that went viral.
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Entrepreneurs recognized a market opportunity and became breeders.  Citizens in Maine, Connecticut, Rhode Island, and Pennsylvania all followed Pike’s lead, and by 1870 this pioneering species had spread south to Texas, north to Montreal, and past the Mississippi River to Iowa. A West Coast population was established with releases in California (1871-1872) and Utah (1873-1874), and in the subsequent decade house sparrows expanded their range from less than 1,200 mi2 to over 500,000 mi2. By the turn of the 20th century the space between eastern and western fronts had nearly filled.
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Why have house sparrows thrived while other species—including some natives—have failed? Here are the keys to making it in America:
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Get lucky.  House sparrows couldn’t have wished for better timing to facilitate their successful acclimation. Steam and internal combustion engines were coming on strong but horses and cattle were still the primary means of facilitated transportation. Working herbivores need more calories than grass and hay alone can provide so corn, barley, oats, wheat, and rice are common additions to the diet. Hoof-stock “exhaust” has a fair amount of undigested “fuel” and resilient city sparrows weren’t picky about where they got their vittles. Additionally, urbanites raised livestock and poultry and a small bird could easily slip in and out of pens and stables to pinch a bite or two. Enterprising sparrows even hitched rides on those new-fangled locomotives and their boxcars filled with grain.
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Grow up fast, breed early and often.  House sparrows eggs hatch after 10-16 days of incubation, nestlings fledge at 14-15 days old, are independent 7-10 days later. One study suggests they may reach sexual maturity as early as 4 months of age—time to find a mate and get busy! Females produce 2-5 clutches of 3-7 chicks per breeding season; that’s an average of 20 chicks per season, per breeding pair. Do the math and there’s your answer.
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Stand up for yourself and your kin.  House sparrows will form loose nesting colonies, are strongly territorial, and will aggressively defend nest sites and feeders. They’ll attack both intruders and potential intruders, and have been known to destroy the eggs and nestlings of competitor species.
. Be smart, adaptable, and adventurous.  Many bird species follow a strict set of guidelines when it comes to choosing where to raise a family.  Sparrows, on the other hand, sparrow nest by gingiber, CCL are willing to at least consider nearly any property when scouting for real estate. You’ll find them nesting in a wide range of locations—nest boxes and tree cavities, of course, but also signs, architectural features, drain pipes, dryer vents, and anywhere else that offers a large enough entrance.  When a potential nesting site has been identified they’ll use every means at their disposal to make it work.  They can even learn how to trip automated door sensors to access food and shelter from the elements and predators. When young house sparrows are old enough to leave the nest they’ll readily disperse 5 miles or more to find new feeding and nesting areas and quickly learn how to claim and exploit available resources.
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Have friends in high places. If you’re a wild thing, having H. sapiens on your side is the equivalent of a royal patronage. In the mid-19th century people trapped house sparrows from one place and released them into new territory cleared of predators and outfitted with nesting boxes.  That, my friends, is what’s called “choosing sides.” Is it any wonder house sparrows are now found in all 48 contiguous states and Hawaii’i (where they were introduced from New Zealand in 1871)? The kindness of human strangers has also allowed P. domesticus to claim much of Canada, all of Central America, most of South America, southern Africa, and eastern Australia.
dark green = natural range light green = introduced range

dark green = natural range     light green = introduced range

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I’m sure you can guess how this story goes, though. It’s been played out countless times in the media—print, broadcast, and social.  First they love you, then they love to hate you.  Americans adore a winner but as any reality TV star can attest, get too successful and fans will take equal pleasure in watching, sometimes facilitating, your fall from grace.
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Even as the house sparrow fad continued to grow, some conservation-minded folk had begun to notice the immigrants were not assimilating as hoped, or following local customs and expectations. Before long, civic leaders had deemed house sparrow nests “unsightly.” Their droppings were blamed for “besmirched” buildings and sidewalks.  They were tagged as thieves who pilfered valuable grain from honest, hard-working farmers. Worse yet, the foreigners were observed being downright inhospitable to the native avian community, including valuable insect-eaters. The nerve of those ungrateful little upstarts!!
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sparrow trap (Albert F. Siepert, Project Gutenberg License)Guides for trapping, shooting, and poisoning the birds were distributed free of charge. By 1883, state legislators in Indiana had declared the house sparrow an outlaw who should be killed on sight. Five years later, Illinois and Michigan had established a small bounty on “English” sparrows and children scrambled to exchange dead birds for cash to buy candy.
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Never mind the fact that human development was having at least as great an impact on native bird species as the house sparrow we had intentionally loosed upon the landscape. Forget that the effects of trapping and poisoning are rarely limited to the intended target species. Ignore the lack of conservation legislation that allowed “market hunting” to bring dozens of wild bird populations to the brink of extinction. The public was frightened and angry about the changes in their communities wrought by industrialization and human migration. Scapegoats were needed to pay the piper for society’s sins and transgressions.
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Many individual house sparrow were killed but despite the all-in extermination effort the species continued to thrive. While no longer hunted for bounties in the US., the bad PR stuck like glue—to this day they are generally resented or reviled. Unlike migratory species house sparrows are not protected in the U.S. and, in fact, the population has declined somewhat.
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save-sparrowFollowing the tried and true media script, the house sparrow is experiencing a rebound in popularity, at least in its native range. This is due to precipitous population declines in England, where this native species has been “red-listed,” Europe, Scandinavia, and India. The problem seems to be a lack of available food for their young—nestlings need the higher level of protein insects provide, only later changing to a grain-based diet. As Rachel Carson pointed out decades ago, our pesticide arms race takes a toll on many of the creatures we enjoy having around. Over the past 10-15 years, “Save Sparrows” campaigns have encouraged home-owners to decrease or eliminate insecticide use, choosing insect-attracting plants, and intentionally increasing nesting sites.
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I’ve yet to see anything in the scientific literature proposing North American as a possible source of imported house sparrows to repopulate their original range but there’s a nice full-circle appeal to that storyline.  Maybe you can go home again.
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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!
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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): Martha de Jong-Lantink, CCL (birds on a branch); Harper & Brothers, PGL (feeding the sparrows); Eric Bégin, CCL (male HOSP); Phil McIver, CCL (female HOSP); gingiber, CCL (HOSP nest); Cactus26, CCL (HOSP distribution map); Albert F. Siepert, PGL (sparrow trap).

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The great egret has made a spectacular comeback from near extinction.

The great egret has made a spectacular comeback from near extinction.

Heat and Humidity have resumed their annual one-upmanship contest here in Arch City. Being outdoors mid-day can be unpleasant, so my canine companion and I have been trying to beat them to the starting blocks by heading out for our daily constitutional as early as possible.
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lafayette square row houses by paul sableman, cclWe stroll two blocks, past grand Italianate manors and restored Victorian row houses, to a handsome mid-19th century city park—the oldest in the Louisiana Purchase Territory. Paved pathways meander through 30 acres of enormous shade trees and lovingly tended flower beds, past fountains, a graceful bridge, and a gazebo, all within the protective embrace of the original cast iron perimeter fence.  There’s even a lake, complete with fish, semi-aquatic turtles, a small flotilla of Canada geese (Branta canadensis), mallards (Anas platyrhynchos), and a scattering of former Easter ducklings. And what Victorian-era water-feature would be complete without a few imperious mute swans (Cygnus color)?
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The park is a hub of activity in afternoon and early evening. The sound of vehicles, emergency sirens, construction and commerce seep in from the surrounding streets, combining with the squeals of children blowing off steam at the playground,  flag football players shouting audibles, or a crowd cheering at vintage baseball game, depending on the season. Fiercely determined joggers make their appointed rounds. Dogs check messages on trees and bushes while their humans check smartphones. Families gather ’round a grill, young lovers picnic on hand-me-down quilts, wedding rings are exchanged, friends play frisbee, and there’s even the occasional free open-air concert or movie night under the stars.
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lafayette park garden path by John, CCLMost mornings, though, it feels like a quiet private garden. The park has become a favorite since my homecoming a couple years ago. GPS may pin my location as near the center of a bustling city but the dappled stillness of this urban oasis, complimented with the music of dancing water and splashes of birdsong, sets an unhurried tone. By the end of our walk I’m ready to step off of cobblestones onto the Information Highway and into my 21st century life.
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great egret by VisitCentralFL, CCLDuring a recent dawn stroll around the lake, I spotted a slim solitary figure standing still as a statue at the water’s concrete edge; a great egret (Ardea alba Linnaeus) doesn’t exactly blend in with the surroundings. There’s simply no point in trying when you’re a 3’ tall bird with a serpentine neck, clad in your breeding season best: extravagant lacy white plumes, a saffron bill, lime-green lores, and long jet-black legs and feet.
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My heart leapt—not because the bird was beautiful (although it was), and not because I didn’t yet have one on my life list (I’ve seen many). No, it was seeing a great egret in this place that brought tears of joy to my eyes.
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bird hat - public domainWhen Lafayette Park was first dedicated, it would have been a rare sight indeed to see those elegant courtship aigrettes on anything other than a lady’s hat.  Great egrets were hunted almost to the point of extinction to satisfy fashion’s dictate that a proper, self-respecting adult female must never be seen in public without a pile of millinery fabric, lace, ribbons, flowers, feathers, and bird body parts balanced on her head. Egret plumes, in particular, were all the rage.
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Concern over the looming disappearance of this and other bird species allowed a fledgling U.S. conservation movement to take flight in the early 20th century.  By 1918, the National Audubon Society and others successfully pressured Congress into passing and funding the Migratory Bird Treaty Act. It was our first serious wildlife protection legislation, and by any measure the Act has been a spectacular success. Many species on the verge of extinction 100 years ago are now doing quite well.  And while hats and “fascinators” are currently experiencing a small uptick in popularity after a decades-long fall from favor, albeit without the wild bird feathers that graced predecessors, their numbers pale in comparison to the great egret renaissance. Although exact population numbers are hard to find, the species is now classified as “common,” numbering in the tens of thousands of breeding pairs, at minimum.
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On this morning, though, it was just a solitary great egret, a noble wire fox terrier (Queen Victoria herself kept one as a pet), and me, the least pedigreed of the group, standing at the intersection of past, present, and future.
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great egret fishing by Alan Huett, CCLI spent a long moment contemplating the significance of a stately creature’s return, and my own, to this historic midwestern park, watching as the bird gazed intently into the water, meditating on the play of light and liquid.
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Or perhaps something both deeper and more practical. Like breakfast.
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Brought back to the here and now by a nudge from my own stomach, I turned toward home. But not before saying over my shoulder, “It was great to see you again—come back anytime!”
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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!

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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 (from top to bottom): Helen Haden (white on black); Paul Sableman (Lafayette Square homes); John (Lafayette Park garden path); VisitCentralFL (strike a pose); Public Domain (woman wearing bird hat); and Alan Huett (fishing).

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gray catbird

Once it begins to sing, any mystery about the source of the catbird’s name is solved (Photo: by Jerry Oldenettel, Creative Commons license)

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Because the semester was winding down, I wasn’t all that surprised to hear a soft, kittenish mewing coming from the small wedge of remnant wooded habitat between my apartment parking lot and the highway. I used to live in a complex near the Virginia Tech campus and, sadly, it’s common for a new crop of outdoor cats to appear as the students disappear. This is not unique to any particular school—it happens in college communities all across the country. People often believe cats are more independent and able to live on their own than dogs… that misperception may have something to do with the lack of guilt they seem to feel over abandoning their once-beloved pet.

But as I scanned the underbrush looking for the source, thinking of what I might use to coax a frightened feline to come out, come out, wherever it was, I came to the happy realization that I wouldn’t be making a trip to the animal shelter after all. It had been a long time since I’d heard a gray catbird (Dumetella carolinensis), and never was I more thrilled by a tune in the trees than on that Sunday morning.

Their call may be the world’s easiest to recognize. Once you’ve heard that “meow,” you won’t wonder another minute how the catbird caught its moniker. Like their relatives, the  mockingbirds and thrashers, these birds are able to copy other sounds and string them together to create a clever mash-up. But their signature song isn’t a case of mimicry—its all their own, shared by every member of the species.

Once my ears were retuned, I heard catbirds calling all over town—another reason to be happy, because this species, which is pretty common in most of its range, has been in decline recently in the southeastern U.S. You’d never know it in Blacksburg, though, where it can sound as though litters of catbirds have been turned loose in the woods.

If not for that distinctive call, you might not even notice these secretive birds. They don’t like to cross open areas so they stick to the thickets, moving in quick hops and short flights through dense vegetation as they search for insects and berries. At first glance, a catbird’s plumage is unremarkable. But look again and you’ll see that slate gray gives way to a jaunty black cap and tail. Look even more closely and you’ll see a rich rusty-orange patch just beneath the tail. That bright flash of pigment always takes me by surprise and makes me laugh—it’s like catching a glimpse of a colorful thong or boxers peeking out of a staid gray flannel suit!

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An example of the gray catbird’s diverse playlist — the first “meow” call is at about the 13 second mark.

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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.

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male american goldfinch

A male American goldfinch glows in sunshine or shadow (Photo: Dale Kaskey, Creative Commons license)

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There’s been a marked decline in the number of sunspots over the past decade or so. That’s what NASA scientists say, and I have no reason to doubt their research findings. Luckily, I haven’t observed any reduction in the terrestrial version of this phenomenon. Hardly a day has passed lately when I’ve not been blinded by the solar flare of a male American goldfinch (Carduelis tristis) as it escapes, briefly, the gravitational pull of a remnant patch of forest.

Actually, woodlots have a fairly loose grip on goldfinches, and they regularly venture out beyond the edge. It’s just that the male’s lemon-colored plumage glows against the inky green shade of conifers and summer hardwood foliage, or a cornflower blue sky, making them even more eye-catching than when the backdrop is amber waves of grain… or weedy native grasses. The undulating flight pattern only adds to the illusion of a plasma flash.

Found throughout the majority of North America for at least part of the year, and in about a third of the continent year-round, these smallish (4-5”) birds are regular visitors to backyards. In fact, suburban sprawl, which has proven so harmful to many wild species—neotropical migrant birds in particular—has been a boon for these devoted granivores. Goldfinches flock to places where thistle, sunflower, dandelion, cosmos, and aster seeds can be found, and development creates the perfect habitat for them and their favorite foods. The popularity of bird feeders hasn’t hurt either, since they provide seed-eaters with a competitive edge over birds that prefer other dining plans.

female american goldfinchAlso known as the wild canary, this species is sexually dimorphic, meaning gender can be distinguished by some physical feature—in this case, plumage. As is so often the case among wild birds, the female American goldfinch’s wardrobe is understated compared to her mate. The sunny palette is still present, but her hue of choice is a dull or olive-tinged yellow, and her wings are a shade or two lighter although similarly marked.

Boy or girl, the gold in those feathers comes from carotenoid pigments in their diet. It’s the same process and components that causes flamingo (Phoenicopterus and Phoenicoparrus spp.) feathers to be pink, coral or orange (the wild ones get their color from the red algae and aquatic invertebrates they consume, while captive birds rely on fortified flamingo chow). Without carotenoids in their diet, flamingos would become a much paler version of the iconic plastic subspecies, and goldfinches would go from 24 to 10 karat.

You are what you eat, you know. So are goldfinches. And even though it’s converted into an amazing variety of forms—thistle seeds, bluegrass, brussel sprouts, mangos, caviar, cheese, chicken chests, and hamburgers—when you get down to basics, we’re all eating sunshine. It just shines more brightly through some of us than others.

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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!

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© 2011 Next-Door Nature— no reprints without written permission from the author (I’d love for you to share my work but please ask first). Thanks to Arthur Chapman for making his photo of a female American goldfinch clinging to a feeder available through a Creative Commons license.

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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

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The Nissan Watering Hole (Photo: Ingrid Taylar, used with permission)

American robins and other wild creatures have to get creative if they want to quench a winter thirst (Photo: Ingrid Taylar, Creative Commons license)

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Which season comes to mind when you read these words?

parched

desiccated

shriveled

arid

sere

If you’re a wild thing, the answer may well be winter.

Sure, the heat of summer can make any body feel dry as dust. But wild animals, especially species that can tolerate living near people, usually have an easier time finding some moisture when the mercury rises than when it falls.

In cities and suburbs, April brings more than just spring showers. The return engagement of automatic lawn sprinklers turns every pampered landscaping leaf and each blade of carefully tended turf-grass into a diminutive drink dispenser. Fountains splash and spritz and spray. Swimming pools drop all pretense of modesty and shrug off their winter coats. Hoses report for car-washing and child-cooling duty, turning streets and sidewalks into ephemeral streams. Birdbaths and pet bowls brim with cool, clear water.

Squirrel lapping water from window (Photo: David Grant, CC license)Come January, February, and March, creatures have to get creative and a bit brave to quench their thirst, at least in northern climes. Those of us with easy access to indoor plumbing may not realize it, but for wild animals, dehydration is a bigger threat to winter survival than starvation. Even when the clouds are feeling generous, the precipitation they deliver is often in a more or less rigid—and much less quaffable—form. Personally, I like to think of sleet, snow, and ice as the H2O equivalent of hibernation. Unfortunately, water’s winter vacation means more work for those who depend on it.

And that’s everyone. No exception. Animal, vegetable (no, not mineral)… if you’re alive, you not only need to consume water, you are water—60 to 80% water. Even critters who sleep away the short photo-period months depend on water to stay alive, same as the rest of us. They simply tank up pre-torpor and then use the water tucked away in their extra reserves of body fat.

American goldfinch drinking from an icicle (Photo: JDB Photos, CC license)Active animals need water for basic metabolic functions, including proper digestion. This is especially true for seed-eating birds (a group that tends to hang around all year rather than migrate to places where insects and fruit are still on the menu) because there isn’t much moisture in their meals. In fact, it takes extra water to digest high fiber foods.

What happens to birds and mammals who can’t find a source of unfrozen surface water when they need it? The problem is far greater than simply putting up with a dry mouth until you can stop at a convenience store for a bottle of Aquafina. How long an animal can go without water depends on many factors, including their species, weight, physical condition, and parasite load, as well as the weather. Generally speaking, though, it doesn’t take long for life without liquid to get unpleasant. Lose one or two percent of total body water (TBW) and your dehydration is classified as “mild”; however, anyone who’s experienced it (that would be me) is sure to argue that the resulting headache is anything but. The definition of “moderate” dehydration is five to ten percent of TBW… the situation is getting serious now, as your skin dries out and loses turgor (the ability to snap back into place when pinched) and your eyes begin to sink back into their sockets. Over ten percent TBW loss is “severe” enough that you’re unlikely to recover without medical intervention.

The scenario I’ve just described may sound like an environmental disaster waiting to happen… and in cases of actual drought, such as what’s been going on in much of the U.S. the past several years, the impact is rather grim. Under more normal circumstances, winter water is difficult but not impossible to find, and this scarcity offers an opportunity for nature lovers. Want to make wild lives—and wildlife watching—a little easier? Turn on the spigot.

I mean that literally. Providing water can be as simple as letting your outside faucets drip. You probably already do this to protect your pipes from bursting when The Weather Channel warns of freezing temperatures. Perhaps you can afford to do it once a week, or every other day, regardless of the forecast.

BluebirdBath (Photo: Rob and Jane Kirkland, CC license)

If you’d rather keep the water bill low, and the wild ones a little further from the house, birdbaths are a simple way to offer refreshment. They’re easy to maintain, plus you can add an electric, battery-, or solar-powered heater/de-icer to insure that everyone can wet their whistle on even the coldest days. Hard-core backyard habitat aficionados will drool over the possibility of installing a pond or artificial stream. Whatever floats your boat—you’ll find both ends of the water-feature spectrum, and everything in between, at your local watchable wildlife retailer or gardening center.  I promise you, the sound of water is irresistible music to human and non-human ears alike. New resources will be found and greatly appreciated.

What’s more, water is an effective wildlife attractor all year long. When you offer seed, you get seed-eaters (e.g., cardinals, blue jays, house sparrows, and squirrels), some omnivores (e.g., opossums, raccoons, the occasional deer or black bear)—and probably a lot of hulls and other waste that needs to be raked up and thrown away. Feeder maintenance can be an expensive and time-consuming habit. [Be warned, you may also inadvertently lure in some species who like to feast on the feeder regulars. If you find it disturbing to look up from your morning coffee to see a sharp-shinned hawk scattering goldfinch feathers hither and yon, you may find it helps to think of this as progressing from “having a feeder” to “having a food-web.”] Landscape with native plants and you should be able to coax some fruit and nectar fans to visit as well. Few homeowners are willing to do what’s necessary to invite insectivores to dinner, at least intentionally.

But offer everyone something to drink and suddenly your crib is a coffee house, local pub, and hot new club, all rolled into one. Just add water!

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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!

© 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: Ingrid Taylar (thirsty robins); David Grant (thirsty squirrel); JDB Photos (thirsty goldfinch); and Rob & Jane Kirkland (thirsty bluebirds)..

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arctic fox by emma j bishop cc

There’s nothing quite as contagious as a yawn* (Photo: Emma J. Bishop, Creative Commons license)

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Grab forty winks. Saw logs. For a species that’s habitually short on shut-eye, we humans sure have come up with myriad ways to talk about it. We also spend a lot of time and money studying sleep, or the lack thereof. Yet, in spite of decades of inquiry, researchers still don’t have a good fix on why we—and just about every other living creature—need to nod off.  We’ve had better luck trying to understand other unconscious states, especially those employed by certain non-human species to deal with hard times.

yawning prairie dog by SearchNetMedia ccWinter poses a critical challenge for animals who stay put rather than migrate to warmer climes. Thermoregulation requires calories, but many foods—especially fruits, nectars, vegetation, and insects—are scarce when the days are short. The ability to reduce one’s energy needs can be a life-saving adaptation. Hibernation does just that—it lowers an animal’s metabolic rate. If all goes well, this period of inactivity, which may last several days, weeks, or even months, depending on the species, will stretch stored energy reserves (aka body fat) long enough for the animal to survive until a greener season. “If” depends on many factors, such as the abundance of autumn food resources, the length and severity of cold days, and even the stability of the den site during repeated freeze-thaw-freeze cycles.

When a critter—let’s use the chipmunk (Tamias spp.) as an example—transitions into a state of hibernation, its body temperature drops to near freezing, breathing becomes so shallow as to be imperceptible, and the heart rate decreases dramatically, from 350 to 4 beats per minute.  Although we tend to think of hibernation as a season-long slumber, chippies and other hibernating rodents do wake up every few weeks to have a snack and take a potty break, even though these periods of activity, called interbout arousals, consume up to 90% of stored body fat. There are some champion nappers in this chisel-toothed group—including the groundhog (aka woodchuck, Marmota monax), who sleeps half its life away, setting the alarm for March when it heads to bed in September.

Other examples of sound sleepers include: insectivores like the European hedgehog (Erinaceus europaeus) and the tenrecs (Microgale spp.); the mountain pygmy possum (Burramys parvus)—the only hibernating marsupial; and the echidna (Tachyglossus spp.), a monotreme.  Biologist recently added the mouse lemur (Microcebus spp.) and the fat-tailed dwarf lemur (Cheirogaleus medius) to the hibernator roster; prior to this discovery, we didn’t have any examples from among the primates. Additionally, since winter temperatures in their native Madagascar may reach 86° F (30° C), it’s become clear that hibernation isn’t strictly associated with cold weather. Nor is it limited to mammals; a bird called the common poorwill (Phalaenoptilus nuttallii) snoozes through at least some of the snowy season.

yawning polar bear by Paul Davidy ccIronically, that most famous of North American sleep icons, the bear (Ursus spp.), is the subject of many a drowsy debate over whether or not they are “true hibernators.” Bears often spend far more time sleeping than the so-called “trues,” so what’s all the fuss about?  Well, this is going to sound like nit-picking, but here goes. First of all, a bear’s heart rate drops, but not quickly enough to suit some scientists. Also, while the number of heartbeats may go as low as 8 per minute, the average is closer to 50 per minute. Moreover, during this time the bear’s body temperature remains pretty close to normal. This is a handy little idiosyncrasy that, should the need arise, allows the animal to wake up fast… and often cranky—a fact Santa (and anyone else) should keep in mind when planning a mid-winter visit to the den.

Taking to one’s bed for months on end could be seen as a rather over-the-top response to a simple cold front. It smacks of swooning characters in English romance novels from the late 1700s. Frankly, it’s not everyone’s cup of tea, and many wild critters take a more measured approach. Torpor is the term commonly used to describe these shorter, less dramatic forms of dormancy, although, technically, hibernation and other types of suspended animation are really subsets of torpidity. Call it what you will, there are examples of “temporary hibernation” in all the Classes of vertebrate animals—mammals, birds, reptiles, amphibians, and fish—and it’s commonplace among the myriad spineless critters as well.

For some of the busiest bodies, torpor is a daily habit. Hummingbirds (Trochilidae), for example, have such a high metabolic rate that they need to ingest a steady stream of non-carbonated sugar water (i.e., nectar) during their waking hours or they’ll become hypoglycemic and too exhausted to fly. Can’t fly? Can’t feed—a vicious circle that will ultimately lead to the bird’s death without some kind of intervention. As you might imagine, this need to constantly refuel creates an enormous problem when night falls and these feathered perpetual motion machines must rest. Without some way to temporarily lower their metabolic rate, hummingbirds would never be able to get out of bed in the morning. Never fear—torpidity to the rescue!

rock dove yawning by Tatiana Bulyonkova ccSwifts (Apodidae), chickadees (Paridae), nightjars (Caprimulgidae), and doves (Columbidae) are just a few of the other avian species who go torpid under various conditions. Generally speaking, these birds are fruit-, nectar-, or insect-eaters, and they tend to be on the small side (less than 80g). The snowy owl (Bubo scandiacus), at 1600-2950g is one exception to this rule, and biologists recently added a second, when it was confirmed that the tawny frogmouth (Podargus strigoides) goes torpid during Australian winters.

Personally, I find these new insights into animal behavior thrilling, because they reassure me that what we know about wild creatures is still a drop in the bucket compared to what we don’t know—there are worlds upon worlds waiting to be discovered on this blue gem of a planet we call home.

yawning turtle by Michael Ransburg ccOf course, cold is not the only hardship wild things would rather sleep through. Periods of drought are just as serious a threat to survival, especially for aquatic and semi-aquatic species. When a lake, pond, or stream goes dry, the inhabitants need to dig in. Literally. Turtles and tortoises (Testudines), crocodiles (Crocodylidae), frogs and toads (Anura), salamanders (Caudata), and some crustaceans will aestivate (also spelled estivate)—a drought-driven form of hibernation. They sink down into the mud before it dries completely, sealing themselves in a mucous capsule until the rains come again. If ever there was a time to be glad you can absorb oxygen in the soil through your skin, this is it, because the air in your boggy bubble won’t last very long.

yawning snowy owl by Pat Gaines ccResearchers are intrigued by these alternate forms of sleep and how they might offer clues for solving a variety of human health concerns. Honestly, I understand their fascination but I don’t know how they stay awake long enough to collect any data. Just writing about dormancy has my eyelid feeling so… heavy. I guess it’s… time for…. me to turn… in.

…..Hit the  [YAWN!]  hay.

……….Catch some…..zzzzzzzzz

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*Pop Quiz:  How many times did you yawn while reading this? 😉

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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. Thanks to these photographers for making their work available through a Creative Commons license: SearchNetMedia (prairie dog); Pau Davidy (polar bear); Tatiana Bulyonkova (rock dove); Michael Ransburg (turtle); and Pat Gaines (snowy owl).

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