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.]

Spotted!

A spotted towhee caught on a fast-food run, and not particularly happy about it.

Supermarket tabloids love just-like-us features so they pay paparazzi top dollar to catch somebodies acting like nobodies. Today I’m focused on the Towhees. They like to keep a low profile but I’m a pro and I know how to find them.

First Rule of Papping: Ya can’t tell the players without a scorecard! It also helps to know the aliases they use to create confusion and avoid detection. See, for a long time all the Towhee’s identified as Team Pipilo. Several years ago, however, about half of them left (were removed, actually) to form Team Melozone. Maybe the rift was media-created (fake news, so sad), or maybe the less flamboyant Towhees felt overshadowed by their more colorful and fashion-forward cousins… who knows? Towheestas, as their fandom are known, love to argue over the distinctions between and relative merits of the two tribes, as well as who should be a P and who definitely qualifies as an M.

Currently,  Team P include the Collareds (P. ocai),  the Green-taileds (P. chlorurus), the Easterns (P. erythrophthalmus), and the Spotteds (P. maculatus), but not so long ago both the Easterns and Spotteds were using the tag Rufous-sided (the Easterns got full custody of P. erythrophthalmus). Spotteds are also referred to in some circles as The Avians Formerly Known as Oregon or Socorro.

Similarly, and to keep things even-steven, Team M also has four members: the Aberts’ (M. aberti), the White-throateds (M. leucotis), the Canyons (M. fusca), and the Californias (M. Crissalis). Oh, but the Canyons and the Californias used to be one big happy tribe, the Browns, even though the Aberts’ and the Californias are probably closer relatives.

Got it all straight? Yeah, it’s a complicated family tree — that’s show biz. Try keeping track of the rest of the Sparrows, not to mention the Barrymores, the Fondas, and the Coppolas.

Second Rule of Papping:  Zoom in on the habitat. Finding out where your luminary lives is a crucial datapoint.  Some Towhees prefer to be on the right side of the continent (Easterns), some are Westerners (Californias, Green-taileds, and Spotteds), and there’s some who meet in the middle. Others Towhees prefer the Southwest (Canyons and Aberts’), or even south of the border in Mexico (Collareds & White-throateds).

Towhees do household chores, just like us!

When it comes to choosing a home base, the Easterns and Spotteds will always opt for a ground-floor unit, if available, ideally tucked in next to a log or of clump of grass to provide some privacy, but they’ll tolerate the higher perches (shrubs) preferred by the Californias, Canyons, and Green-taileds. The Aberts’ are the only Towhees who like to live in a tree-top high-rise. Not much is know about where the Collareds and White-throateds homestead because they’re a secretive bunch who’ve put down roots far from the limelight’s glare, in the more rural setting of Mexico’s mid-to-high altitude subtropical and tropical pine-oak forests. They’re a rare and lucrative shot but too remote for run-and-gun photography.

A Spotted spotted at the spa.

Improve your chances by becoming a regular at all of the places your subjects like to eat, including the local hipster farmers markets and upscale grocers, where they shop for household supplies, as well as favorite watering holes and spas. If you can get a neighborhood exposure you’re golden because that’s where life gets real. As the playground K-I-S-S-I-N-G song tells it, first comes love, then comes marriage, then comes baby in a $700 Bugaboo carriage. Actually, these days marriage is an option, not a certainty. Regardless of the parents’ living arrangements and legal status, or lack thereof, nest/crib beta is pivotal for a paparazzo because editors drool when there are kids in the picture — Mommy & Me outings are always Money Shots.

A California towhee takes her mini-me out for lunch.

Third Rule of Papping:  Know your subject inside as well as out. In other words, not just their look but the idiosyncratic behaviors that will tip you off to their presence, even when they’re not wearing breeding plumage. For example, you’ll want to know that all the Towhees like to forage for food using a unique two-footed backward hop, followed by a pert bend-and-snap. Well, I assume this includes those camera-shy Collared and White-throateds but who the hell knows. If the pickin’ are slim, or maybe too predictable, Spotteds will scan the shrubbery for snacks, and the Aberts’ have been known to poke around under the bark near the bottom of tree trunks for some grub.

Family comes first for the Canyons and Green-taileds, who have a reputation for forming long-term, monogamous pair-bonds. If a Green-tailed mom senses danger, she’ll bravely flee from home on foot with a conspicuously raised tail to attract and distract the predator’s attention from her children.

A California fascinated with its reflection in a window.

It will probably come as no surprise, that the Cali Crew has an ongoing love/hate relationship with their image — you’ll see them in front of a freshly washed window, handy car mirror, or any other reflective surface checking out their visuals or talking to themselves in a very critical, territorial tone. They’re not crazy, just a little left of center. They like to chill in stands of poison oak, feeling all cutting edge because this hangout hasn’t been “discovered” yet, gobbling up the pale berries as if they were caviar.

Last, but not least… shut up and get the shot. Sure, the relationship between some celebrities and the paparazzi is symbiotic— they get publicity, you get residuals. Towhees don’t play that. If you want to be successful with this dynasty you’ll stay quiet, blend into the scenery, keep your eyes open, and your finger on the trigger. Be the early bird that catches the worm. Not that Towhees are worms. Far from it. Truth is, they’ll eat that worm for breakfast… and you could get it all on film (or a memory card).

[Thanks to the following photographers for making their work available through the Creative Commons license: Dawn BeattieCalypso Orchid, TJ GehlingDoug Greenberg, Scott Heron, Lucina M, Mike’s Birds, Jorge Montejo, JN Stuart, Ingrid TaylarUSDA, Francesco Veronesi, and Yutaka Seki.  © 2017 Next-Door Nature. Reprints welcomed with written permission from the author.]

Summer Soundtrack

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). 

Damsels and dragons… but no prince

damsel fly at rest, Next-Door Nature, urban wildlife

This lanky damsel isn’t waiting for a charming champion to rescue her (or him?). It’s just resting up for another mosquito-shopping trip (Photo: Tomquah, Creative Commons license).

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Once upon a time there was a damsel(fly).

[Imagine, if you will, a bucolic Disneyesque soundtrack of flutes and piccolos in the background.]

She (Or maybe he. This is a modern fairly tale.) explored the lovely little pond from which s/he had recently emerged after having spent most of life underwater as a nymph.

Who would have guessed during that awkward adolescence, when growth spurts had him/her literally jumping out of her skin a dozen times or so, that she would transform from an ugly duckling into a swan? (Speaking of awkward… let’s just stick with “her” from here on out for the sake of simplicity, shall we?)

So… today was her debut. A coming out, of sorts, and the damsel(fly) flitted here and there, enjoying the warm sun shimmering and gleaming on her iridescent wings as she dipped down to the water now and again to daintily snack on mosquito larvae.

Not a care in the world.  Completely oblivious to…  [Cue the ominous bassoon music] …the looming presence of a dragon(fly) on the other shore.

Not that it mattered, really. [Can I have the flutes and piccolos back, please?]  Sure, the dragon(fly) was part of the Epiprocta clan, the damsel(fly) a Zygoptera, but they were both members of the Order Odonata. No family feuds that she knew of, and so closely related were they that many folks had trouble telling one from the other without assistance in the form of a handy reference table.

They were cousins, but not kissing cousins. No interspecies hanky-panky here, even though their kind were known as having an unusual approach to romance. You see, instead of offering a wake-up kiss, the male clasps the female behind her head with a special appendage on the tip of his abdomen. IF she welcomes the embrace, instead of sliding her foot into a size 6 glass Louboutin slipper eventually she loops her abdomen forward to pick up the spermatophore from a structure on his abdomen and deliver it to her spermatheca [Latin is a romance language, remember].

I know, I know… it sounds kind of weird and kinky but trust me, it’s just hard to describe. When it’s right it’s a beautiful thing, especially when the couple forms a kind of heart with their entwined bodies [Everyone say “awwwww”].

Sometimes they even become members of the Mile-High Club, flying united for a little while. But damsel(flies) and dragon(flies) aren’t the marrying kind. They’re independent and self-sufficient—a characteristic that begins in infancy. Good thing, too, because, to be perfectly honest, the adults are neglectful parents. Dad is no prince, zooming off with hardly a backward glance at the new Mom-to-be, who’s no queen of the nursery herself. She deposits her eggs in floating plants or directly into the water and then washes her (metaphorical) hands of the responsibilities of child-rearing.

The nymphs (aka naiads) hatch and, being carnivorous little monsters, begin feeding on mosquito larvae, daphnia, tadpoles, small fish, and sometimes each other.

That happens among adults as well, although the jury’s still out on the subject of postcoital cannibalism, a not-uncommon behavior in the insect world. It’s enough to give a girl pause (although, for most insect species it’s the guy who needs to worry about fatal attractions).

Whatever. This is the 21st century and females of every stripe and species are all about DIY.  Gals today don’t need a prince to save them. Locked up in a tower? Any modern, self-respecting damsel knows you simply pull out your smartphone, Google instructions for making a rope out of sheets, and then shimmy down to freedom.

Evil stepmother? Please. Dial the Child Abuse Hotline and tell that witch you’ll see her in court!

Face to face with a dragon? Reach for your trusty catch-pole or tranquilizer dart gun apps.

And live happily ever after.

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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!

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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: [starting from the top]: Tomquah (cover damselfly); Photo munki (nymph… not the same species); Clifton Beard (mating damselflies); Ben McLeod (dragonfly eyes); and Charles Lam (damselfly eyes).

Social network

next-door nature, urban wildlife, wasps, yellowjackets

Love Facebook? You might want to thank a paper wasp (Photo: roadsidepictures, Creative Commons license)

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Mark Zuckerberg would not be one of 100 wealthiest and most influential people in the world without the help of wasps. I mean the six-legged kind (whether or not two-legged WASPs should get any of the credit is something for attorneys to discuss and will not be addressed here).

It’s a lengthy timeline but easy enough to follow*:

wasps to Facebook timeline

There you have it—no social insects, no social primates and, therefore, no need for a social network. When you think about it, Facebook isn’t just an online community. It’s a kind of virtual hive. You and Mark owe more to wasps that you may have ever realized.

next-door nature, wasps, mud dauberNot all wasps are gregarious, mind you. The majority of species, including mud daubers (Sphecidae), pollen wasps (Masarinae) and potter wasps (Eumeninae) are solitary. You know the type… quiet, poorly developed interpersonal skills, keep to themselves, rarely cause much trouble. A lot of them don’t even have stingers and they take the term “wasp-waisted” to extremes. We’ll respect their privacy, at least for now, and come back for a visit some other day.

Meanwhile, here in the U.S. we have two basic types of social wasps: paper wasps (Polistes spp.) and yellowjackets (Vespula spp. and Dolichovespula spp.). The two groups are often lumped together under the “hornet” tag, but the introduced European hornet (Vespa crabro) is the only true member of that Family found in North America.

With a few exceptions, wasps have two pairs of wings and can be distinguished from bees by that narrow waist (aka petiole) between the thorax and abdomen. The ovipositor (an organ used to prepare and position eggs) of a fertile queen becomes the stinger of an infertile worker females; males are not capable of stinging. Unlike honey bees (Apis spp.), wasps do not leave their stinger behind and are able to deliver multiple injections of venom.

Adult wasps feed on nectar and, as a result, can be classified as pollinators. Some social wasps are omnivorous, feeding on fallen fruit as well as carrion; yellowjackets are especially attracted to open garbage cans and dumpsters, drawn perhaps to the sweet, sticky spillage from nearly empty soda cans and bottles as well as other types of decaying leftovers.

next-door nature, wasp, yellowjacket

yellowjacket (Vespula germanica)

Wasps come in a rainbow of colors, including vivid yellows, metallic blues, and bright reds (keep this helpful rule of thumb in mind when interacting with insects—flamboyant wardrobes usually serve as a “don’t touch!” warning, backed up with some kind of poison or venom). Because they often share a brown or black and yellow color scheme, paper wasps are often misidentified as yellowjackets. I don’t want to encourage you to get up close and personal to make the identification and, luckily, there’s no need. The easiest way to tell them apart is by their nests.

Paper wasps and yellowjackets will nest in trees, under building eaves, in walls, and just about any other place that offers some protection from the elements. Both types of wasp use chewed wood fibers as the main construction material, even when building underground, as yellowjackets often do.

next-door nature, wasp, paper wasp, wasp nestPaper wasp combs attach with a single filament and consist of one tier of adjacent papery hexagonal brood cells for developing larvae. Each cell is open on one end  so you can actually see the contents, if you choose (but please keep a safe distance. Better yet, just look closely at the opening photo above). Typically, a mature nest contains 20-30 adults and rarely grows to more than 200 cells. Paper wasps usually attack only when they or the nest is threatened, but they are territorial. As an interesting aside, the northern paper wasp (Polistes fuscatus) has extremely variable facial patterns and recent research suggests their facial recognition abilities are similar to those of humans and chimpanzees (Pan spp.). Obviously, individuality affords some benefit, even among drones—so much for faceless anonymity.

Yellowjackets prefer to raise their young in a kind of fortress that looks more like what we would think of as a hive, with layers and layers of brood cell combs. The whole structure is completely enclosed with the exception of a single entrance hole. Queens establish new colonies each spring, often returning to the site of a previous nest (the location is identified by a chemical scent marker recognizable even to a first-year queen). However, if the structure is particularly well-protected from the weather—in the wall of a house, say—it may become a perennial nest, populated year-round. Yellowjacket hives may range in size from several inches (at the beginning of the colony’s history) to enormous structures measuring six feet or more and housing as many as 20,000 adult workers.

Wasp control is dangerous, especially for people who have heart conditions or known allergies to the venom, so it’s important to know what you’re dealing with before you take action. There’s a huge difference between avoiding 20 winged assailants and outrunning 20,000.  Moreover, yellowjackets tend to be more aggressive—they don’t give up the pursuit as quickly. [For more information on how to safely manage wasps, download a fact sheet courtesy Drs. Mike Merchant and Glen Moore of my alma mater, Texas A&M. Whoop!]

Don’t be too quick to declare war on wasps, though. In addition to their important role in plant pollination, nearly every pest insect species has at least one wasp species that preys or parasitizes it, making wasps a critically important natural biocontrol that benefit agricultural and even home gardeners. If that’s not enough to convince you to live and let live with wasps, when possible, image your life without social media!

I’m serious—next time you see some wasps congregating around your front porch, take a moment to say thanks… just before you blast the nest with with the hose, knock it down with a broom handle, and then grind it into the sidewalk with your shoe to be sure there are no survivors (don’t act all innocent with me—I can see that can of Hot Shot® behind your back).

When you’re finished, don’t forget to post about it on Facebook!

 

*NOTE:  As new discoveries are made, scientists continually discuss, argue, and refine our understanding of the evolutionary history of life on Earth.  I realize this timeline is simplistic but it is based on currently available research. My intention was to create a captivating introduction to a post on wasps by illustrating a connection between Zuckerberg, social networks, and the Vespidae Family. If you have a nit to pick about my portrayal of the fossil record and its accuracy—cut me a little slack, okay? I’m a writer and an urban wildlife biologist, not a taxonomist. Plus my beloved MacBook Pro died last week so I’m way behind schedule, stressed out, and in mourning (I did pull myself together long enough to purchased a new MacBook Pro and, I must say, it has been incredibly supportive as I struggle overcome my grief.)

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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] roadsidepictures (paper wasp on nest); Malcolm Tattersall (mud dauber); Richard Bartz (yellowjacket on leaf); Bob Peterson (paper wasp nest in situ); and Jason Hollinger (yellowjacket nest).

Village voice

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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© 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).

Sparks

firefly in someone's palm

Fireflies, also known as lightning bugs, are as much a part of summer in some American suburbs as the smell of newly mown grass (Photo: Jessica Lucia, Creative Commons license)

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Walking through a nearby park at dusk the other night, I saw a single spark. Then another. Soon there were too many to count, hovering in the airspace between my chin and my ankles, lighting my way past the pond, the gazebo, and the tennis courts.

Who needs a time machine when you have memory to transport you to another place, another you? Those sparks must have kindled a few synapses, because suddenly I’m six-years-old again, running with my best friend Cindi through freshly mown grass that envelopes us in the signature scent of a suburban summer while staining the soles of our feet DayGlo green. Wild with excitement at being allowed to stay outside after dark, we’re relentless, ruthless, giggling predators intent on imprisoning lightning bugs in an empty Miracle Whip® jar.

If you live in the eastern half of the U.S., tell your neighbor or coworker you watched fireflies last night and see happens. I’ll bet you, dollars to donuts, their faces will soften and glow as if bathed in the bioluminescence of an impromptu nightlight. It’s Proust’s Remembrance of Things Past all over again, but with Coleoptera instead of cookies.

Firefly by Art Farmer, Creative Commons licenseThat’s right, they’re not flies and not technically bugs either. They’re beetles, a group that doesn’t usually garner much affection from the human race. Let’s face it—we like our non-human animals to have fur or feathers and large liquid simple eyes. If you can make your butt blink on warm summer evenings, however, folks are willing to see you in a new light.

Special organs in the abdomen convert oxygen and a compound called luciferin into a yellow or chartreuse glow. They’re quite good at this, by the way. Common incandescent light bulbs convert only 10% of an energy supply into light; the other 90% is emitted as heat. Fluorescent bulbs transform 90% of the energy into light but fall short of the nearly 100% efficiency of a firefly’s “cold” light.

As kids, we learn that fireflies flash to find a mate. What you may not know is that each species—and there are many different species in North America alone—has it’s own unique light show. This helps everyone pair up correctly. Males fly around broadcasting a kind of visual Morse code to the females hanging out in or near the grass. When a female spots a familiar pattern she flashes a response, then they signal back and forth until the male finds her.

Some flash patterns warn away predators who’ve come to associate an unpleasant meal with a specific blink beat. This doesn’t work with every predator, juvenile Homo sapiens being one obvious example.  Often, though, the biggest threat comes from a relative—some species are able to mimic the unique display pattern of their kin to trick the males and… well, use your imagination. Or, better yet, let Isabella Rossellini explain it to you.

Returning from a reverie of 1965 to present day, I had a vague sense of something missing. Then it hit me—I didn’t see a single child with a jar in pursuit of bobbing, weaving cold-light moonbeams!  I found this disturbing. Disheartening.

My own lifelong fascination with the natural world wasn’t sparked by National Geographic Specials about exotic creatures living halfway around the world (although, in time, those programs came to have an impact as well). There’s no doubt in my mind that my love of all things wild started as a toddler, sitting in my mom’s lap in the backyard watching cardinals grow bold with curiosity as she whistled their calls—Birdy-birdy-birdy! Cheer-cheer-cheer!—back to them. It blossomed because, as a grade-schooler, I was allowed to raise tadpoles in galvanized buckets, catch crawdads in plastic cups, tie thread-leashes to the legs of June bugs, and run after lightning bugs with mayonnaise jars.

Maybe, if I’d been walking through a subdivision, I’d have seen evidence that the spark that caught fire in me all those years ago still has a chance to ignite wonder in the up-and-coming generation. Maybe there are thousands of children darting across thousands of lawns after millions of flashing yellow lights all across the U.S.  I hope so.

But can we really afford to leave it to chance? I don’t think so. So do me a favor, would you? Find a kid you know. Pull an empty jar down from a cabinet shelf and poke some holes in the lid. Then go outside after dinner tonight, catch some fireflies, and light a spark.

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© 2011 Next-Door Nature— no reprints without written permission from the author. Thanks to Art Farmer for making his photo of a firefly in flight available through a Creative Commons license.

Long time no see

male green anole

The male green anole flashes his brightly colored throat to claim territory and attrack females (Photo: Ken Slade, Creative Commons license)

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When I was in Austin about a month ago, I ran into an old acquaintance… kinda-sorta. I was having a glass of wine at the Hyatt Regency’s outdoor bar when, out of the corner of my eye, I recognized someone I haven’t seen since I left Texas over a decade ago. Actually, I found it hard not to notice, since he was doing push-ups against the patio railing, but the other hotel guests seemed oblivious. As he moved closer to my table I turned to face him, thinking, “Typical attention-seeking anole.”

A green anole (Anolis carolinensis), to be exact, although he has a number of aliases including Carolina anole, American anole, and red-throated anole, not to mention tree lion. I’ve also heard people say he’s a green anole changing colorchameleon. Trust me, he’s not. Oh, he can change color alright, within a limited green-to-brown range… mostly when he wants to fade into the background or broadcast to everyone that he’s stressed, cold, or generally displeased. But while he does have roving eyes, they don’t move independently of one another.

When I say “he” I don’t mean it in the gender-neutral pronoun way—I’m certain this particular reptile was a male. Why? Because he would periodically take a break from pumping up to flair the strawberry-hued flap of skin on his neck called a dewlap. It’s the anole equivalent of “hey, baby… can I buy you a drink?” Or throwing up gang signs to claim a corner. A dewlap is dual-purpose.

Or maybe it’s really all one and the same. In the anole world, you’ve got to be a property owner to be a playah. A male’s territory overlaps those of multiple females. Green anoles are polygynous, meaning a guy will wander through his ‘hood flashing throat bling and making social calls. The little women, on the other hand, stay pretty close to the homestead, waiting for their man to come around. It’s basically polygamy, but for any number of irrational reasons, people prefer to use different terminology for analogous human and non-human behavior.

female green anoleWarming temperatures raise lizard libidos, so depending on the local climate, the party starts sometime in April and doesn’t wind down until late August/early September. Courtship is simple and not all that subtle. Once a male’s bobbing head and dewlap have caught a female’s attention, she lets him know she’s in the mood by arching her neck… which he subsequently bites from behind. Understandably, this can cause her to reconsider her level of receptivity, so he has to hold on tight. I guess all that upper-body work has a purpose beyond posing after all.

The encounter lasts a minute or two and then they go their separate ways, at least for a couple of weeks. She lays a clutch of 6–9 eggs that take 5–7 weeks to hatch. Neither parent gets involved in child-rearing. What can you expect? Young anoles grow up fast and are having babies of their own at 8–9 months of age.

Back on the patio. I said hello, asked how he’s been, the usual slightly awkward pleasantries that pass between acquaintances who’ve not seen each other in a long while. As I remember he never was much of a talker, but he seemed particularly distracted that afternoon. A quick glance around and I understood why. I cut my conversation with this lounge lizard short once I realized he looking past me at a couple of slender green ladies who were checking him out.

Typical.

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© 2011 Next-Door Nature— no reprints without written permission from the author. Thanks to Alex Calderon (color change) and e_monk  (brown female) for making their photos available through a Creative Commons license.