Urban development

Raccoons by John Biehler, Creative Commons license

Just hangin’ on the corner with the homies… smart, bored, and looking for trouble (Photo: John Biehler, Creative Commons license)

[Another reprint, this one from February 2012. I’ve been traveling over the holidays and due to some family-related changes to the itinerary I haven’t had much time to write. New stuff is coming, though. I promise. And is there a better way to start a new year than with raccoons? I think not!]

World War II had barely ended when researchers began to notice a major migration under way in North America, from undeveloped and agricultural areas to cities and suburbs.  Now, in the early 21st Century, the urban population is over 20 times that of the early-1940s—in some places, more than 50% higher than the surrounding rural landscape. With growth has come all the problems that naturally occur as a community becomes overcrowded: housing shortages and squatting; dumpster diving; increases in theft and property damage; sanitation-related public health concerns. sometimes, we all need a little help getting through the day... by jmtimages, creative commons licenseAll of this has a tendency to make established residents less tolerant of immigrants, even when the new neighbors are clever, ambitious, hard-working, good parents, and undeniably cute as all get-out.

Raccoons (Procyon lotor) may be new to the urban scene, but… oh, you probably thought I was talking about people, right?

That’s understandable, I suppose. Just about everything I’ve said to this point could apply to humans as well. There’s no denying that Homo sapiens is now an urban species. The tipping point (>50% of humans living in areas of high population density) came around 2007. Each year, more of us are lured by the promise of better-paying jobs, more housing options, access to social services and chain restaurants, bigger shopping malls, a larger dating pool, and high-speed Internet connections. In other cases, concrete tentacles sprawl past the city limit signs to grab up and devour surrounding countryside, forcing rural residents to choose between relocating to land that hasn’t yet caught developers’ eyes and becoming accidental townies.

urban raccoons by liz west ccThe “built environment” is intended to meet the wants and needs of our own kind, but raccoons may be better suited for what we’ve constructed than the target real estate market.

Raccoon Nation, a documentary that aired in the U.S. on the PBS “Nature” series, and in Canada on the CBC News Network series “The Nature of Things with David Suzuki,” makes a strong case in support of that thesis.* As filmmakers follow the furry urbanites in their native North America (including Chicago and Toronto—known as the “raccoon capital of the world”), as well as in Germany and Japan (where they were intentionally introduced), it’s hard not to notice the similarities between those who construct cities and those who exploit them and their work.

How alike are we? Let’s build this case from the ground up.

raccoon paw and human handFeet—humans and raccoons are both plantigrade. In other words, we walk with the entire foot planted firmly on the dirt… make that asphalt. There are other examples (elephants, kangaroos, and pandas come to mind), but the majority of mammals walk on their tippy toes (more on this in a future blog post).

Hands—okay, technically raccoons don’t have hands, they have two more feet. Or you could say they do have hands but they just happen to use theirs for walking. That’s all semantics, though. Look closely and you’ll see one reason it’s so hard to invent a raccoon-proof container—a paw that looks a lot like a palm and a digit that’s as close to the functionality of an opposable thumb as it gets for non-primates.

dumpster raccoons by zeetz jones ccStomachs—the best way to avoid starvation long enough to pass your genes along to the next generation is to cultivate the ability to eat anything and everything you can cram in your mouth that contains a calorie. The human diet is astonishingly diverse, and urban raccoons gobble up everything we leave on our plates and toss in the trash… plus a lot of stuff we would rather not eat. Some researchers suggest that omnivory played a crucial role in human development—by providing a more consistent and more nutritious diet, and because finding potential new foods, determining whether they are edible, and figuring out how to eat them pushed our brains to create new neural pathways. Which brings us to…

Brains—raccoons and people also share a high level of behavioral plasticity, a term that implies the ability to change. Flexibility, adaptability, and life-long learning (well… we both have that capacity; whether we use it or not is another issue). With no email to check, no AYSO games to attend, no need to commute, and only one significant predator (those commuting automobiles), raccoons have plenty of time for learning. Each day is devoted to DIY personal growth, lifestyle enhancement, and honing useful skills, such as…

  • how to turn a garbage can or dumpster into a convenience store;
  • how to tight-rope walk a fence (great for avoiding the neighbor’s dog);
  • how to shimmy down a tree branch onto a rooftop;
  • how to turn a loose shingle on that roof into an attic entrance;
  • how to turn that attic into a cozy, rent-free nursery.

Whether you find these critters endearing or exasperating, it’s never fun to clean up refuse that’s strewn across your yard, and there’s no denying they can and do cause damage to property. Ironically, our attempts to outwit them are molding these savvy metropolitan mammals to better fit the world we built for ourselves. And here’s the other reason I will never invest my hard-earned money in some inventor’s guaranteed raccoon-proof fill-in-the-blank: because no human being will ever have as much time to devote to keeping a raccoon out of something as raccoons, often working in teams, are willing and able to devote to cracking the code. By trying to thwart them, we’re simply selecting for the traits that make a more worthy opponent and a better urban animal. An über-coon, if you like.

bipedal raccoons by David~O ccBefore you know it, they’ll be standing upright in line right beside us at Starbucks, waiting for a Venti Caramel Macchiato to help them wake up for the night shift.

Urban raccoons share another, disturbing commonality with their human neighbors—the toll exacted by easy access to a plentiful, high fat, high sugar, high calorie diet. Diabetes, hypertension, and cardiovascular disease may do more to limit their numbers, in the long run, than all the Hav-A-Heart trap-toting home and business owners, urban wildlife biologists, and nuisance wildlife control operators combined. Cleverness and dexterity are no match for the fearful symmetry of a predatory heart attack or kidney failure.

No wonder they call it the urban jungle.

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© 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: John Biehler (3 sepia raccoons); jmtimages (mother & child); Liz West (supper club); Stuti Sakhalkar (human handprint); Jon Stogner (raccoon pawprint); Zeetz Jones (dumpster ); David~O (bipedal).

Us against the world

coyotes by larry lamsa creative commons license

Coyote couples are as destined to misfortune as any literary star-crossed lovers, but a lot more reproductively successful (Photo: Larry Lamsa, Creative Commons license)

[In honor of my visit to New Mexico, during which I’ve had far less time to write than expected, a reprint from February 2012.] 

Boy meets girl.

It’s such a familiar story I don’t even need to spell out the rest, right?

Ah, but folks do love their stories to have a beginning, a middle, and an ending.

Ok, ok… so a male and a female find one another.  They “meet-cute” (the classic contrivance of romantic comedies), or through the efforts of micro-managing parents (the historically classic approach), or online, or in one of a million completely unremarkable-to-everyone-else ways—the “how” doesn’t matter (except to the starry-eyed pair, of course). A spark catches and a bond is formed… perhaps by rite (mating or marriage rituals, depending on one’s religion, politics, or species), or at first sight, or possibly over time. They find a home, start a family, and live happily enough ever after (fairy tales tend to gloss over the details of that last part).

It’s a comforting, feel-good saga but it’s not the stuff of legends, or of Pulitzer Prize winning novels, or Oscar accolade dramas. No, for that we need a star-crossed couple, thwarted by outside forces. We need Romeo and Juliet. Catherine and Heathcliff.  Edward and Bella. A pair of coyotes.

coyote in grass by trey ratcliff, creative commons licenseWyle E. and the Mrs. may not be icons of romantic literature, but one would be hard pressed to find couples more destined to misfortune than those of the Canis latrans clan. It’s all here—blood and poison, class and caste, honor and artifice, cruelty and revenge… and then some. After all, the persecution most luckless lovers experience only lasts three Acts, or about 100,000 words. Coyotes have been wearing a target since shortly after European settlers, and their livestock, came to North America in the early 15th Century.

Many species have disappeared into extinction under far less pressure yet, despite hundreds of man-hours and billions of dollars spent annually to wipe coyotes off the face of the Earth, as a species they continue be fruitful and multiply. To survive. To thrive.

urban coyote by ken slade creative commons licenseUnlike their close relative the wolf (Canis lupus), the coyote’s range has expanded in response to human development and programs to exterminate wolves, a key natural competitor. Prior to 1700, coyotes were almost solely creatures of the prairies and deserts of the central United States and Mexico. Now they can be found as far west and north as Alaska, in all but the northernmost reaches of Canada, across the entire “lower 48,” as well as much of Central America, and in habitats as diverse as protected wildlands and urban centers.

How is this possible? Chalk it up to intelligence and adaptability. Behaviorally, coyotes are as flexible as a yoga instructor regarding everything from where to live, what to eat, and even family size and composition.

By 12 months of age—and there’s about a 60% chance a pup will survive his or her first year—coyotes are old enough to start looking for a mate. They don’t always leave home or settle down right away, though. Adults may live alone (for at least part of their life), in pairs, or in packs comprised of an alpha male and female and their offspring from previous years.  Once mated, they form perennial, monogamous bonds; however, on average, “till death do we part” is only a couple of years. In captivity, coyotes can live about as long as domestic dogs (Canis familiaris)—13 to 15 years—but in the wild few live to see their third birthday. Dying young is a familiar theme for the romantically doomed, be they canid or primate.

coyote pups by zac garrett creative commons licenseEveryone in the family unit—Mom, Dad, and any older sibs who haven’t left home—pitches in to rear the current generation of pups; it takes a village to raise coyote kids, too. Litters average four to seven pups, although—and here’s another example of that flexibility I mentioned earlier—coyotes litter size goes up or down based on how much food is available and how many of their brethren live in the neighborhood. In other words, when humans remove (almost always by some lethal method) coyotes from an area, causing the population density to fall, the next breeding season will see a rise in the number of pups per litter. And in the case of the loss of an alpha pair, the remaining pack members may disperse, find mates, and begin raising pups of their own, so the area ends up with more breeding pairs than before any effort was made to reduce their numbers. One could argue that, however counter-intuitive it may first appear, extermination programs are a great way to increase your coyote crop.

last laugh by matt knoth creative commons licenseWell, what do you know? Play your natural selection cards right, and it’s possible to turn the tables on those who try to sabotage your relationship and have the last laugh—talk about a plot twist!

Perhaps the folks who try to control coyotes would find it helpful to read a few Victorian romances. Then again, anyone who’s tried to keep besotted teenagers apart should understand that when it comes to ill-fated lovers, where there’s a will, there’s a way. Come to think of it, maybe Cyrano and Roxanne, Tristan and Isolde, and Jack and Rose should have taken a lesson or two from a couple of cunning characters dressed in fur. They may not have cheated death, but they’ve managed to leave behind generations of children, and grandchildren, and great-grandchildren to tell their tale.  From Once Upon a Time to…

The End.

EPILOGUE:  Lest anyone think I’m unfairly choosing sides in the war against coyotes and other wild predators, readers should know that I understand the narrative presented above is not the whole story. I used a literary device to focus attention on a particular aspect of the coyote’s natural history—pair-bonding and social structure—and I intend to return to this and other species featured on this blog again and again over time, as is necessary to flesh out these complex and fascinating creatures.

While I may not always agree with their production practices, I don’t begrudge farmers and ranchers their right to make a living and protect their investment. I’m an omnivore who depends on the plant and animal foods they produce. However, I do find it strange that many who own livestock will point to the fact that coyotes, wolves, and foxes kill cows, sheep, and chickens as proof of their inherent cruelty, and as justification for implementing lethal control measures—even though many, if not most, of these domestic animals are being raised as food and will eventually be killed by the same humans who cry foul when the grim reaper appears on four feet in a pasture instead of on two at the processing plant.

As a biologist, I know that life feeds on other life. That’s the way of the world and I don’t see it changing any time soon. I just think we should be honest about our motives (and I’m aware that I risk offending some readers with what I’m about to say): It’s not that we don’t want that lamb or calf to be killed and eaten; it’s that we want to be the only ones who get to eat. That strikes me as fundamentally wrong-headed, because it perpetuates the idea that people are somehow removed from the natural world.

Here in the U.S., we’re already paying to have both livestock and predators on our public and private lands, and have done so for a long time. But the true cost of tonight’s meatloaf or hot wings isn’t visible on the grocery store receipt, in the form of the higher meat prices livestock producers might charge to pass along the cost of losses to predation (or non-lethal prevention methods). Instead, part of the price of our food is disguised, hidden as taxes that support inefficient, ineffective, and often brutally cruel control programs. Personally, I prefer to know how much my dinner really costs, financially and ecologically.

You may disagree, as is your right.

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© 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: Larry Lamsa (two coyotes and a pup); Trey Ratcliff (coyote in grass);  Ken Slade (coyote on the street); Zac Garrett (coyote pups); and  Matt Knoth (last laugh).

Runner-up

Two male turkeys audition but fail to impress the judge (Photo: Teddy Llovet, Creative Commons license)

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[An alternative to the trussed and roasted turkeys featured as the unlucky guests of honor on tables across the U.S. this week, reprinted from November 2012.]

I don’t know what American grade school kids are being taught these days—I left Oakville Elementary a couple of decades ago (okay, fine—several decades ago) and since I haven’t had kids of my own I don’t have access to 21st century homework assignments. But I’ll go out on a limb here and bet that most of them know the bald eagle (Haliaeetus leucocephalus) won the 1782 version of American Idol, and that it did so by edging out celebrity judge Benjamin Franklin’s favorite contestant, the wild turkey (Meleagris gallopavo).

That long-ago contest had little in common with the popular modern day version of reality TV. For one thing, neither bird has great pipes. Citizens were never asked to call or text in their votes. Also, the bald eagle has held on to national fame longer than fellow white-headed winner Taylor Hicks, while the turkey hasn’t exactly proven the voters wrong by, say, winning an Academy Award, Jennifer Hudson-style.

On the other hand, we don’t set aside a day each November (or any month, for that matter) on which the eagle takes center stage.  So in honor of Thanksgiving, I’d like to briefly sing the praises of the runner-up… and not just as the star performer at a holiday dinner.

Shortly after Congress immortalized the eagle on the Great Seal of the United States, Franklin shared his disappointment and misgivings over their choice in a letter to his daughter. Given the sparse pelt on his own pate, one might expect ol’ Ben would view the bald eagle as a kindred spirit, or at least harbor a bit of sympathy. Instead, his criticism was as harsh as any doled out by Simon Cowell, describing our new national symbol as “a Bird of bad moral character” who “does not get his Living honestly,” preferring to sup on rotting fish or, worse yet, stealing fresh seafood from more industrious raptors like the osprey (Pandion haliaetus). What’s more, Ben argued the eagle is cowardly, evidenced by how easily it can be driven away by much smaller birds defending their nests and offspring. Not exactly the role model image our fledgling country hoped to cultivate.

The turkey, according to Franklin, is “in Comparison a much more respectable bird,” a “true original Native of America” and a “Bird of Courage” who “would not hesitate to attack” any invader and defend his home turf.

This description might not square with your expectations after years of holiday stories featuring dim-witted, less than inspiring  Butterballs-to-be but the domestic turkey is but a pale and passive imitation of the real-deal.

Wild tom turkeys (as the males are called) will most definitely defend their breeding territory against potential rivals. Large and heavy, they are unexpectedly agile flyers, aggressive fighters, social, sometimes playful, intelligent, and adaptive.  To my knowledge they’ve never been accused of theft or caught dining on carrion (their omnivorous diet consists primarily of acorns and other nuts, seeds, fruit, buds and leaves, insects and the occasional small reptile or amphibian).

As far as moral character goes… well, you know rock stars. Toms strut their stuff in a flamboyant palette of iridescent red, green, purple, copper, bronze, and gold feathers worthy of Adam Lambert. No piercings or tattoos, but oozing cool with a Beat-worthy statement beard of stiff bristles starting just above the wishbone, wattles (flesh hanging from the head and/or neck), caruncles (fleshy growths on the head), snoods (long fleshy object draped across a tom’s beak), spurs and other body art. Their ladies, in keeping with general avian fashion trends, tend to be more conservatively dressed but they can strut like a runway model  when warranted, complete with long legs and outlandish makeup. Out of the spotlight, turkey hens are attentive mothers to their precocial offspring, in contrast to the menfolk, who are polygamous absentee fathers.

(Male bald eagles, it must be said, are actively involved in their children’s upbringing; given his own reputation, Ben might have been well served to heed the old saying about people who live in glass houses before he cast the first stone.)

Like the bald eagle, wild turkeys experienced a perilous decline in their numbers during in the last century, due to overhunting and habitat loss (rather than DDT exposure, as was the case for so many of our birds of prey).  Game agencies took action to protect the species and have been successful in helping the population rebound. So much so, in fact, that turkeys have not only returned to rural fields, pastures, and woodlands but have begun to tour in many major metropolitan areas as well.  In some parts of the country spotting a flock of wild turkeys foraging near a highway, hanging out downtown, or feasting at a backyard bird feeder is no longer a novelty.

That means a growing number of Americans now have a ticket to see  this national treasure up close and personal more than once a year, and at venues other than a serving platter.

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© 2012 Next-Door Nature—no reprints without written permission from the author (I’d love for you to share my work. Just ask first.). Thanks to these photographers for making their work available through a Creative Commons license: Teddy Llovet (cover); keeva999 (turkey in flight); Mic Stolz (plumage); Peter Patau (men).

Treehuggers

I’ve been called a treehugger more than once in my life, and while I know the comments weren’t intended as such, I always take them as compliments. As a sobriquet it’s both true and false: true, because I do spontaneously hug exceptionally handsome or venerable trees; and false, because compared to the practiced professionals who scamper up and down tree boles every waking hour of their lives, my embraces are too amateurish to qualify as authentic hugging.

Sure, as a kid I would climb trees and hang from the larger limbs by my knees. We had several sturdy silver maples in our yard and I loved spending time in these leafy hideouts. But there’s more to being a treehugger than practice. I simply don’t have the body to become world-class, or even marginally proficient. To compete with the Eastern gray squirrels (Sciurus carolinensis) in my neighborhood, whose arboreal acrobatics would make a Cirque du Soleil gymnast green with envy, I would need a significantly different anatomy.

For example, I would need to lose enough weight (and height) to allow the friction created by the pressure of my paws gripping a small branch to overpower gravity’s bullying attempts to push me rudely onto the ground.

A better sense of balance would also be necessary if I were to have any success as a legitimate treehugger. I’m not saying I trip over myself on a daily basis but, as friends and family can attest, when I do fall it’s Charlie-Brown spectacular… and usually on my face.

Tree squirrels, in comparison, are masters at controlling their center of gravity. This can be attributed, at least in part, because they can hold on equally well with both hands and feet.  Here again I’m disadvantaged, and I place full blame on evolution, my DNA, and whichever hominid ancestors of mine, after climbing down from a tree on an African savannah, decided that standing upright and using feet almost exclusively for the precarious task of bipedal perambulation was a much better way to go than remaining quadrupedal.

My filed and brightly polished toenails would have to go, replaced by strong, sharp claws that could easily pierce porous bark or hook onto an uneven edge (completely impractical for someone who wears socks and sleeps under a blanket, though). Whereas humans, including me, need at least three points of attachment when climbing, this adaptation allows squirrels to secure their position with only two attachment points, and to grasp new surfaces at angles most animals would find impossible.

Most important of all, I would need feet that can pivot on a swivel joint, allowing my ankles to rotate backwards so I could hang from nearly vertical surfaces.

If I’d been born a flamboyantly fluffy-tailed rodent then maybe, just maybe, I could latch on to a wrinkle in the tree rind and hang by my toenails while enjoying a leisurely acorn snack. Alas, ’tis the fault in my stars to peer ever and enviously skyward, my feet with their simple-hinge ankles planted on the firmament at the base of the trunk, and looked down upon with curiosity and pity (I assume) from the higher-ups.

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[Thanks to the photographers made their work available through the Creative Commons license: Mr.TinDC, Artful Magpie, JoeInQueens, and Jed Sheehan.  © 2017 Next-Door Nature. Reprints welcomed with written permission from the author.]

R-E-S-P-E-C-T

An opossum in the snow

A Virginia opossum braves the snow to look for an early evening meal (iStock/twphotos, used with permission)

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[I’m on the road this week and looking forward to seeing some snow! With that in mind, I decided to reprint this piece from 2010. A new NDN post is in the works for next week.]

A dusting of snow always makes it easier to see who’s been out and about in the neighborhood. Bird tracks don’t provide much insight into genus and species, but opossum tracks are recognizable enough. Several of them—or maybe it was one very busy guy or gal—live along a favorite walking route of mine.

example of opossum paw printsOpossums are down with life in and around town, in part because they are the penultimate omnivorous opportunists. In addition to their “traditional” cuisine, which features insects, small vertebrate animals, wild fruits (including persimmons, a special treat), and carrion, ‘possums are known to take advantage of uncovered garbage bins (not without risk, as they often fall in and become trapped) and bird feeder spillage. They’re not shy about venturing through a pet door now and then either, especially if there’s a beckoning bowl of kibble on the other side. This can come as quite a shock—to both parties—when the homeowner wanders into the mudroom or kitchen expecting to say good morning to Garfield or Odie.

If ever there was a creature in need of a good spin-doctor, it’s North America’s only marsupial. The Aussie cousins—kangaroos, wallabies, koalas, sugar gliders, even wombats—have somehow garnered a higher charismatic ranking than poor old Didelphis virginiana.

Their long snout, gray fur, and naked tail cause many city and suburb folks to mistake them for rodents, and this may be the root of their public relations problems. I remember a wildlife center phone conversation with a woman surprised and frightened by an opossum who wandered through the pet door into her laundry room.  Eventually, I was able to calm her down a bit by convincing her she was not dealing with a freak-of-nature rat, but my attempts to help her appreciate the natural beauty standing in front of her dryer fell on deaf ears.

Startled Woman: I’m sorry, but I can’t even stand to look at him… he’s just so UGLY!

Indignant Wildlife Biologist (that would be me): Well, ma’am, he’s probably thinking the same thing about you!

Not one of my finest Wildlife Hot-Line moments, I know, but the words were tumbling off of my tongue before I had a chance to bite it. I happen to find opossums quite handsome. Still, there’s no denying that rodent resemblance. If you are mouse-and-rat adverse you’ll probably never come to think of ‘possums as pretty.

There’s another problem—it’s a common misconception that ‘possums are clumsy, dirty, and not all that bright, with poor vision and hearing to boot.

Don’t believe it.

Personally, I think any species that’s managed to survive relatively unchanged since the Cretaceous deserves a little more credit. Modern humans arrived on the scene nearly 90 million years later, so perhaps we should be a little more respectful of our elders.

Opossums are actually quite clean. They carefully groom themselves during and after eating—even the babies. When it comes to the acuity of their senses, common knowledge has it all wrong. These marsupials have excellent hearing and can easily detect the rustling of prey hidden under dry leaves or tree bark. A wildlife rehabilitator friend who works extensively with opossums tells me they evolved with a focus on olfactory sensitivity and, as a result, have an extraordinary sense of smell. Their sight is about average for mammals, but because they are primarily nocturnal, their eyes are adapted to working under low-light conditions. Our daytime is their night and, as a result, they can appear rather dazed and confused in sunlight.

Kind of like me when I’m up past my bedtime.

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© 2010 Next-Door Nature — no reprints without written permission from the author.

Vert-de-Gris

Cope’s gray treefrog on a pepper plant. Photo: Alan Howell © 2017, Star Path Images, Used with Permission.

It isn’t easy being green. Kermit the Frog said it, so you know it has to be true.

He’s always seemed a reluctant celebrity, so my guess is that being the most famous Muppet-amphibian on the planet isn’t always a picnic. I wonder whether life would be a little less stressful if, like some of his cousins, Kermit could change from green to another color when he’d rather not be so conspicuous.

North American gray treefrogs know how to be seen and when to blend into their surrounding, shifting the spectrum from bright emerald to peridot, to gold, copper, platinum, silver, and even gunmetal. Since the places they hang out — trees and shrubs in woodlands, meadows, prairies, swamps, suburbs, and cities — tend toward palettes awash with green and gray hues, these arboreal amphibians can keep their sartorial choices simple. 

What looks like a costume change is actually a rather high-tech, cellular-level special effect created by chromatophores. These pigment-containing and light-reflecting cells, or groups of cells, are present in the skin of certain frogs, as well as some reptiles (including chameleons), cephalopods (such as octopi), fish, and crustaceans. Mammals and birds, on the other hand, have melanocytes, a different class of cells for coloration.

Chromatophores are classified based on their hue under white light:

  • melanophores (black/brown)
  • cyanophores (blue)
  • erythrophores (red)
  • xanthophores (yellow)
  • leucophores (white)
  • iridophores (reflective or iridescent)

The process, known as physiological color change, can be controlled by hormones, neurons, or both. Most studies have focused primarily on melanophores because they are the darkest and, therefore, the most visible. When pigment inside the chromatophores disperses throughout cell the skin appears to darken; when pigment aggregates in cells the skin appears to lighten. Either way, you’ve got an amazing makeover, or a convincing disguise, in no time flat! 

There’s even more to the gray treefrog’s ability to assume an alter-ego than meets the eye —what appears to be a single species is actually two very close relatives: Hyla versicolor, aka Eastern, although there’s a long list of pseudonyms from which to choose (there are more ways to hide than blending into the substrate); and Hyla chrysoscelis, aka Cope’s (which also has a couple of nicknames but not as many as H. versicolor).

Cope’s and Eastern are equally skilled at clinging to and climbing slick surfaces using large toe pads that secrete mucous, creating surface tension. It’s not uncommon to find one plastered against a window pane (allowing for an interesting view of their nether-regions). Both species prefer a diet of small insects, spiders, and snails. Both hibernate under leaves, bark, or rocks. Well, “hibernate” sounds a lot more cozy than the reality… which is that their bodies pretty much freeze and their lungs, heart, brain, and other organs stop working until they thaw out and reanimate in the spring. It’s a pretty nifty chemical trick, on par with being able to transform your complexion at will. 

Kermit has an unmistakable personal brand, but distinguishing H. versicolor from H. chrysocelis visually is just about impossible. Both Eastern and Cope’s are relatively small (1.5—2.0 in/3.5—5 cm), and the adults are often mistaken for younglings. Both wear a sweep of bright citrus-orange along the inseam of their hind legs (a signature shade is all the rage, you know).  Females of both species are usually (but not always) larger, with a ladylike white throat. During the breeding season, males have a macho (make that hipster, since it resembles a beard) black, gray, or brown throat. Guys sing. Gals swoon, but don’t sing along.

The ranges of these two species overlap, but Cope’s are more widely distributed. If you find a gray treefrog in North Carolina or Georgia, you can be reasonably certain it’s a Cope’s, but if you’re in Iowa or Pennsylvania, all bets are off. The only risk-free way to know for sure is to do a DNA test — Cope’s are a diploid species, meaning they have two sets of chromosomes, one from each parent (for a total of 24); Easterns are a tetraploid species, meaning they have four sets of chromosomes (for a total of 48).

Now, some frog call connoisseurs claim they can detect variations in breeding calls, and that Cope’s treefrogs have a faster and slightly higher-pitched trill than Easterns. But the call rates of both species change with ambient temperature… so color me skeptical.

[Postscript:  What kind of frog is Kermit? While I’ve never found a definitive answer to this question, I always assumed that because he was created/discovered by Jim Henson, he was probably Hyla muppetalis or Rana hensonii… something like that. However, in 2015 Brian Kubicki of the Costa Rican Amphibian Research Center discovered a frog who, if not the same species, must at least be a first cousin, or possibly Kermit’s doppleganger.]

Diane’s bare-hearted glass frog (Hyalinobatrachium dianae). Photo: © Brian Kubicki, Costa Rican Amphibian Research Center, Used with Permission

[Thanks to the photographers who granted permission to use their photos, and to those who made their work available through the Creative Commons license: Dave Huth(composite of color variations), , Chiswick Chap & CheChe, (melanophores schematic), Alan Wolf, Andrew Hoffman, and Douglas Mills© 2017 Next-Door Nature. Reprints welcomed with written permission from the author.]

Track & Field

cottontail leaping

Back to school, and to early morning practice before class – hop to it!

[Students are returning to my university town for the start of another academic year… so in honor of college athletics I’m offering a slightly-edited instant replay of this post about cottontail rabbits that originally ran back in April 2011.]

On your mark…. Get set… HOP!

An article I read while eating breakfast had me thinking about track meets as the terrier-boy and I set off for our morning walk.  That piece may be why I noticed, for the first time, how runners imitate the posture of a rabbit as they settle into their starting blocks. Human runners have to fold themselves up to gain the potential energy advantage of a crouching leg, but rabbits are always ready for the starting gun.

sprinters

In 2009, Usain Bolt set a record of just over 23 mph in both the 100- and 200-meter, but he’s an exception even among world-class athletes. It’s nothing out of the ordinary for Sylvilagus floridanus to reach speeds of 18 mph, and they can maintain that speed for close to 800 meters… while zig-zagging to change direction every few strides. Let’s see Bolt try that!

racing cottontailsMost sprinters are specialists, but cottontails and other Lagomorphs, with the exception of pikas (Ochotona princeps), also excel at hurdles, steeplechase, and in some field events. Okay, they can’t throw a javelin or a shot-put, but they leap to the top of the score board when it comes to jumping.

leaping cottontails

Longing to see a long jump? At first glance, a cottontail’s 4.8 m (15 ft) may not sound too impressive when compared to current world record holder Mike Powell’s 8.95 m (29.4 ft), set in 1991. But consider this: a 4.8 m leap is 10x the average length of an adult cottontail’s body; 9 m is barely 5x the average height of an adult American male.

How high can they flycottontail courtship? The men’s high jump record stands at 2.45 m (8 ft), set in 1993 by Javier Sotomayor of Cuba. That’s only 1.4x the average height of Olympic jumpers. While courting, both buck (male) and doe (female) cottontails will jump 0.6 m (2 ft), nearly twice their height, to demonstrate worthiness. By that standard, not even elite human athletes would be able to find a mate.

cottontail courtship 2Once the mating ritual (which also includes a little boxing, just to keep things interesting) is complete, 1-12 kits are born approximately 28 days later. A doe will often mate again within hours of giving birth—what a woman! Admittedly, she’ll only visit the nursery when it’s time to feed the kids so she’s not going to win any “most attentive mother” awards. But, to be fair, compared to her baby-daddy she’s a doting parent, and staying away keeps predators from getting wise to the location of the nest. It will take her 3 weeks to wean one set of youngsters, then she’s got about 1 week to recuperate before the stork arrives again.

Still not impressed? She may have up to 7 litters in a single year.  Now, I call that a marathon.

[Thanks to the following photographers for making their work available through the Creative Commons license: Porsupah ReeRob Helfman, and Michale Connell.  © 2011 Next-Door Nature. Reprints welcomed with written permission from the author.]

Oddly Normal

I don’t live far from the eclipse’s Path of Totality, but I decided to stay put just the same. I didn’t even order eclipse glasses. I know there will be plenty of great video to watch throughout the day, and since my sweetheart is a talented professional videographer, I feel like I’ve got that angle covered.  I want to focus on what’s going on down under, here on Earth.

In anticipation, I’ve been reading stories about how the event will impact wildlife. Every single one of these reports has focused on the “strange” animal behavior we can expect to witness as the day goes dark… and I find that very strange indeed.

What these experts are calling odd is considered completely normal activity when it happens each evening. And from the descriptions I’ve read about what to expect, assuming night is nigh would be a perfectly reasonable assumption for any creature—human or non-human—who doesn’t have a television or an Internet connection and, therefore, doesn’t know that the sun will be playing hide-and-seek with the moon for a little while today.

Humans tend to be less familiar with nocturnal species than the ones who are active during regular business hours. I think the eclipse is going to offer a chance to get to know our neighbors who work the night shift… kind of like a rerun of the National Night Out that took place earlier this month.

As the light begins to dim, creatures who are active during the day may start their usual bedtime routines.  Some diurnal birds will sing one last serenade to the daylight as faux-evening falls…

…some will hurry back to nests of eggs or chicks…

…others will congregate for mutual protection, as they do at the end of every day.

Birds who love the night life will wake, possibly feeling less than rested but still ready to boogie in search of an early breakfast (or late dinner, depending how you look at it).

Some wild mammals are active and visible during the day, including a fair number of rodents such as tree squirrels, groundhogs, prairie dogs, and chipmunks. I’m expecting the eclipse to be a great time to see mammals who are usually waking up just as I’m starting to wind down…

Insect musicians will surely want to set the mood with a tune or two.

Fireflies know a little night music calls for romantic lighting…

…and amphibians aren’t about to let the invertebrates steal the limelight!

As the skies brighten we’re also likely to have a second dawn chorus… but without needing to get up before sunrise! So don’t despair just because the eclipse will pass your part of North America by, or because you don’t know how to make and use a pin-hole camera (even after you Google’d instructions). There should be some amazing wildlife sights to see, right here on good ol’ terra firma.

 

[Thanks to the following photographers for making their work available through the Creative Commons license: Eric Kilby, Dan Dzurisin, Ingrid Taylar, Pat Gaines, Rachel Kramer, Will WilsonTony Oldroyd, Michael Eisen, Elizabeth Nicodemus, USFWStsaiian, David Huth, and Ingrid Taylar.  © 2017 Next-Door Nature. Reprints welcomed with written permission from the author.]