You are currently browsing the category archive for the ‘amphibians’ category.

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.

.
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.
.
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.
.
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.
.
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.
.
Common true katydids (Pterophylla camellifolia) shift the accent…
.
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]

.
Before long, the dog-day cicadas (Tibicen canicularis) are stealing the show.
dog-day cicada by Roger Engberg, CCL
.
.
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!
.
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.
.
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.
.
The American toad (Anaxyrus americanus) is a minimalist; not much complexity but the sustain on that single trilling note is impressive.
.
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.
.
Tiny boreal chorus frogs (Pseudacris maculata) play plastic comb call-and-response…
.
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!
.
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.
.
.
© 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). 

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

.

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.

For that, I am thankful.

.

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 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).
red-bellied newt (Photo: janetcetera, Creative Commons license)

Red means STOP… at an intersection or on an amphibian. The red-bellied newt secretes a deadly neurotoxin (Photo: Janetcetera, Creative Commons license).

.

Double, double, toil and trouble; 
Fire burn, and cauldron bubble. 
Fillet of a fenny snake, 
In the caldron boil and bake,
Eye of newt, and toe of frog,
Wool of bat, and tongue of dog,
Adder’s fork, and blind-worm’s sting,
Lizard’s leg, and owlet’s wing…
 

During late October, Shakespeare’s recipe for chaos and conflict comes to mind with the sudden appearance on our very doorsteps of all manner of terrifying witches, ghosts and goblins… and political advertising.

The former can be bought off easily enough with bite-sized Butterfingers (a sticky booby trap that guarantees revenge for the extortion in the form of future dental bills).  The latter are a bigger headache, far more demanding, and incredibly persistent. It takes more than a simple head of garlic and the promise of your vote to repel the legions of wannabe legislators. What American needs now, more than ever before, is a magical charm … a powerful protective talisman to ward off bleary-eyed baby-kissing, hand-shaking, promise-making shape-shifters.

rough-skinned newt (Photo-:Judy-and-Ed, Creative Commons license)We need newts.

The amphibian kind; NOT the mammal and former Senator from Georgia.

“Powerful” is probably not the first word that comes to mind when you spy a newt in any of its four developmental stages. Each egg, attached to an aquatic plant during the main breeding season of June and July, is actually quite vulnerable, even when the female makes an effort to fold it inside a leaf. Nor is the larval tadpole menacing when it emerges about three weeks later. That is, unless you are algae, a small invertebrate, or a sibling (fratricide is an all too common practice in this sweet old eat-and-be-eaten world of ours).

newt tadpole (Photo: Mark Kilner, Creative Commons license)Over the next several months, however, a metamorphosis as extreme as any werewolf’s takes place. Where once only a big-eyed head and tail existed, legs buds sprout and lengthen. Feathery external gills are absorbed, replaced by internal lungs. Fully formed efts, as they are now called, will then drag themselves on stubby legs out of the natal pool and venture onto dry land … but the scene doesn’t evoke Creature from the Black Lagoon panic.  At two to six inches in length, adult newts are easy to overlook, generally more slender than their salamander cousins, and not physically threatening in the least.

It’s during the larval transformation that some species also develop a bright, cautionary coloration that hints at their ingenious and formidable defense strategy:  toxic slime.

california newt (Photo: Ben Amstutz, Creative Commons license)All amphibians carry potentially harmful bacteria, such as salmonella. The California (Taricha torosa), rough-skinned (T. granulosa), and the red-bellied (T. rivularis)—known collectively as the Pacific newts*—aren’t satisfied settling a score by giving their adversaries some stomach cramps and the runs, though. They practice biological warfare, secreting tetrodotoxin (TTX), one of the most potent neurotoxins known to science.  TTX, which gets it’s name from the pufferfish (Tetraodontidae) that also carries this poison, is deadly when ingested or when it comes into contact with mucous membranes or breaks in the skin. Within as little as 20 minutes after consuming the toxin the victim will experience respiratory paralysis, and there is no antidote.

Perilous times call for strong medicine but just to be clear, I’m NOT suggesting that poisonous amphibians should be used to rid the world of legislators. Only that in our effort to demand more from elected officials than the ability to raise money and speak in soundbites, we might gain inspiration from a small, seemingly insignificant creature with hidden powers disproportionate to its size.

A newt, perhaps.

Or a voter (not to belabor the point).

But maybe we should heed the lesson of Macbeth’s witches, who certainly knew a thing or two about politics and ambition, and take precautions to insure that newt-power is used exclusively for good and never for evil. After all, Order Caudata, with their ability to regenerate limbs and tail, as well as eyes, hearts, intestines, jaws, and spinal cord, are the envy of many a zombie… and any politician who wants to transform (temporarily) into a more centrist candidate following a contentious primary season.

.

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; 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]: Janetcetera (red-bellied newt); Judy-and-Ed (rough-skinned newt); Mark Kilner (newt tadpole); and Ben Amstutz (California newt).

next-door nature, urban wildlife, fence lizard

Everyone, even fence lizards and other ectothermic creatures, are feeling the heat these days (Photo: Bandelier National Monument, Creative Commons license)

.

Temperatures across the southern half of the U.S. are soaring into triple digits, so I was trying to think of creative solutions to beat the heat when it hit me—why not become cold-blooded!

next-door nature, urban wildlife, fox squirrelAlas, my brain must have overheated. Once air conditioning allowed a cooler head to prevail I realized that what seemed like a brilliant idea while baking beneath a blazing sun is absolutely, completely, utterly impossible… and not simply because mammals cannot will themselves to undergo metamorphosis.

You see, technically there’s no such thing as a cold-blooded animal (unless you’re speaking metaphorically about someone who lacks emotion or empathy).  Or a warm-blooded animal, for that matter. Both terms are shorthand for the ways in which body temperature (aka thermophysiology) is controlled in different types of organisms.

Most mammals and birds are classified as endotherms (Greek: endon = within; thermē = heat). For these critters thermoregulation is an inside job, primarily by way of metabolic processes. Under extreme environmental next-door nature, urban wildlife, sunbathersconditions some physical mechanisms come into play, but not solar energy (at least, not directly). If the mercury plummets and the body’s core temperature begins to drop, muscles shiver to create warmth; if the core temperature starts to rise the body perspires to cool via evaporation. No sweat glands? Pant like a dog… or birds. All evidence to the contrary, since humans are mammals, swimsuit-clad sunbathers dozing in rows on a beach or poolside with icy drinks standing at the ready are, in fact, capable of maintaining a relatively constant body temperature.

next-door nature, urban wildlife, gray treefrogWhen an animal’s body temperature is strongly influenced by ambient conditions it’s an ectotherm (Greek: ektós = outside). Fish, amphibians, reptiles, and invertebrates rely on external heat sources to get their juices flowing, especially during the chillier seasons or cooler times of day. That’s why these animals can be seen basking on rocks, roads, and any other warmth-radiating surface. Then, when they can’t stand the heat they get out of the kitchen, retreating into shade, water, or underground to cool off (Sound familiar? We really are more alike than different).

Take-home message: mammals and birds are endotherms; invertebrates, fish, amphibians, and reptiles are ectotherms.

Except when they aren’t.

It’s the exceptions that make the rule, right? Let’s begin with the usual ectotherm suspects. According to one source, 2% of invertebrates are endothermic. Regrettably, the informant failed to name names but, in spite of the fact that spineless animals are not my strong suit, I did managed to chased one down—snails and slugs (Oops, that’s two… and “chased” may be overstating things).  Fish, being vertebrate species, are my regular beat so I can state with certainty that billfish (e.g., sailfish, marlins), tuna (Scombridae), one family of sharks (Lamnidae, including makos and whites), and one species of mackerel (Gasterochisma melampus) are endothermic… at least to some degree. I’ve yet to find a reliable report of an endothermic amphibian, but among the reptiles sea turtles exhibit both ecto- and endothermic traits.

next-door nature, urban wildlife, echidnaMoving along to the endothermic exceptions… Hummingbirds (Trochilidae), swifts (Apodidae), and common poorwills (Phalaenoptilus nuttallii) all experience periods of lower body temperature and metabolic rate; therefore, some biologists argue they have ectothermic traits. Additionally, there are mammals—certain rodents, a couple of lemurs, and many bats—that enter hibernation or estivation in response to low temperatures or drought, respectively. Then there’s the echnidna (Tachyglossidae), a “primitive” mammal from Australia that’s an ectotherm eleven months of the year and an endotherm during the month when it lays its eggs (Yes, eggs. If you like rule-breakers Australia is your Mecca. In the interest of time and space, though, we’ll have to save monotremes for another day).

What I’ve presented above is a fairly simplistic description of thermophysiology.  Why stop there? Because a more thorough treatment would require a good deal of nuance and a complicated discussion of sub-categories, not to mention a stiff drink (the current temperature is 99°F and rising—make mine a frozen margarita).  But since it’s so hot I’ll go ahead and venture past a toe in the water… up to my knees, but no further.

next-door nature, urban wildlife, elephant shrewOne subset of the endotherms are tachymetabolic (Greek: tachy = quick), organisms with a consistent and extremely high metabolic rate. Shrews (Soricidae) are a perfect example—diminutive beings with massive appetites, their metabolic rate is at least five times that of similarly sized ectotherms. Being able to snack non-stop and still rock a bikini probably sounds too good to be true. It is. Finding a constant supply of calories without access to fast food and grocery stores is no picnic. Bradymetabolic (Greek: brady = slow), which could easily be mistaken for bipolar disorder, is no bed of roses either. These organisms swing wildly between a high (when active) and low (when resting) metabolism, usually based on either external temperatures or food availability. (If you think someone else has got it better, rest assured you probably don’t know the whole story.)

As biologists refine our understanding of how bodies work, language evolves and once popular terms like cold-blooded fall from favor. Popular stereotypes suggest otherwise, but scientists are not completely immune to trends. When I was an undergrad, for example, the preferred word for organisms influenced by changes in ambient temperature was poikilotherm (Greek: poikilo = varied, irregular). Although still useful for making distinctions between types of ecotherms, the term is used less frequently now and may be on it the way out.

next-door nature, urban wildlife, crocodilesC’est la vie. Styles change, in both the lab and on the beach (Thankfully. I’m old enough to remember when Speedos were all the rage in men’s swimwear). I’d be willing to bet, though, that most Earthlings won’t give up sun worship any time soon. Chillin’ in a sunbeam feels too good, whether you need it or not (at least as long as there’s a pool nearby).

.

Start your day with a little Next-Door Nature—click the “subscribe”  link in the upper right-hand corner of this page and receive notifications of new posts!
© 2012 Next-Door Nature—no reprints without written permission from the author (I’d love for you to share my work. Just ask first.). Thanks to these photographers for making their work available through a Creative Commons license: Bandelier National Monument (sunning fence lizard); Michael V. Flores (fox squirrel cooling down); Nick Papakyriazis (sunbathers); geopungo (gray treefrog); BohemianDolls (elephant shrew); and Jess Loughborough (basking crocodiles).
wildlife and roads, wildlife watching, wildlife habitat

Roads are both a blessing and a curse for wildlife (Photo: Colleen Greene, Creative Commons license)

.

Ever dreamed of going on a safari? Then fasten your seat belt, start the engine, and hit the road. Any road. I’ll bet you dollars to donuts—take the time to look and you’ll spy enough wildlife to satisfy, Bwana.

Sure, some of the creatures will be easier to spot than others… for the simple reason they’re no longer moving.  But I’m not proposing a road-kill road-trip. Trust me, the city streets, shady neighborhood boulevards, highways and byways offer plenty of opportunities for wildlife watching. Naturally, the species on display depend on the size of the road, its location, the season, time of day, and the speed limit.

wildlife and roads, vultures, wildlife watchingLet’s say your motoring down a divided highway, a conduit to and through the all-American suburbs. The big stuff (aka megafauna), such as deer, elk, moose, bears, and even coyotes, can be seen at 65+ mph (although not always in time to either admire or avoid them). Certain birds of prey, red-tailed hawks in particular, can be seen at both speed and distance due to their habit of hanging out high on handy utility poles to scout for snacks. Anything more petite will be visible only if it’s on the shoulder or trying to cross the road. Scavengers looking for a free lunch can be seen out on the open road day (crows, ravens, vultures) and night (opossums, coyotes). That meal ticket can quickly turn the diner into dinner for someone else… and so on.

wildlife and roads, wildlife watching, groundhogBeyond mowed blacktop borders, in the woods and taller grasses, you’ll find rabbits, foxes, raccoons, skunks, and groundhogs. Based on my own non-scientific observation, to improve your chances of seeing these meso– (medium-sized) species as well as small but brightly colored male songbirds in situ you’ll have to ease up on the gas pedal and let the speedometer drop to 35-45 mph, tops.

A bicycle (or even a horse if you have access to one) would probably set the right pace for a rider to notice mice and voles, lizards, turtles, frogs and toads, as well as female songbirds (who tend to have less flashy wardrobes than their ready-for-the-disco menfolk). The truly diminutive critters—insects, spiders, snails and slugs—are hard to spot at more than arm’s length so it’s best to set off on foot and plan for a leisurely pace if spineless quarry is your goal.  A general rule: the slower you go, the more you’ll see—that’s what makes the backroads more appealing for this kind of trip than a superhighway.

In poetry, novels, song, and cinema people often speak of the allure and romance of roads—the ones that calls us, the ones less traveled, the ones that go on forever, choosing between high ones and low ones. Wild animals rarely have access to books and mp3 players and RedBox kiosks, though, and I’ve never found them to be all that interested in popular culture… so what’s the attraction?

To build a road through a previously undeveloped area, the first thing that happens is clearing a swath of the existing plant community, be that trees and shrubs or grasses or cacti. Once the project is completed (or even while it’s still in progress) new plants begin to colonize the bare soil, creating a plant community that’s different from the surrounding landscape along with an edge where new and old meet.  Disturbing the soil stimulates the germination of seeds that may have sat dormant for a long time waiting for the right conditions. Soil may be brought in from somewhere else as part of the construction process along with seeds from plants that are completely novel in this setting.

wildlife and roads, wildlife watching, wildlife habitatSince the plants predict what kind of animals will be found in any ecosystem, the new habitat creates opportunities certain wildlife species will exploit… but in most cases it won’t be the species that were living happily in the pre-construction habitat. Edge species will colonize the area, often using the right-of-way as a travel corridor before and after the road is completed. Some organisms will hitchhike to their new home on and in the bodies of larger animals or even motor vehicles. Birds, bats, and flying insects will drop in from above. Wild things are always jockeying for space and there’s no such thing as a vacant lot in nature—at least, not for long.

wildlife and roads, wildlife watching, pronghornMake no mistake—roads are a significant cause of habitat loss and their presence is detrimental to many types of wildlife. For others, though, the resulting edge provides exactly what they need to thrive. This includes our most familiar next-door nature species. In fact, the reason blue jays, robins, white-tailed deer and other edge-loving species are so common in human communities is because Homo sapiens is also an edge-loving species. Our roads are simply one very conspicuous example of that fact.

The natural world is never static; it’s always in flux and each day there are new winners and losers.  Are roads good or bad for wildlife? It depends on the species. But there’s no doubt they are a boon for wildlife watchers.

.

Life is better with Next-Door Nature—click the “subscribe”  link in the upper right-hand corner of this page and receive notifications of new posts!

© 2012 Next-Door Nature—no reprints without written permission from the author (I’d love for you to share my work. Just ask first.). Thanks to these photographers for making their work available through a Creative Commons license: Colleen Greene (black bear); e_monk (black vulture); Matt Reinbold (groundhog); MoDOT Photos (edge habitat); Allan Harris (pronghorn).

pacific tree frog (photo: jacki dougan, creative commons license)

Frogs, including this Pacific tree frog, could use a little help as they try to survive in the 21st Century (Photo: Jacki Dougan, Creative Commons license)

.

Fifty years ago, Rachel Carson asked the world to consider a simple question: imagine springtime without birdsong.

Silent Spring addressed an unlikely subject for what was to become a best-selling book—the effect of DDT and other pesticides that persist in body tissue, becoming more and more concentrated as they move up the food chain (a process known as biomagnification). Yet nearly everyone could easily understand that their own quality of life would be diminished should they step outside one sunny May morning to find the dawn chorus had been replaced with a deafening stillness.

green treefrog (Photo: sarowen, Creative Commons license)Thanks to Carson’s courageous stand—and the subsequent public outcry—songbirds and other avian species dodged a bullet.* Now there’s another set of wild voices in the spring choir who could use a hand—the amphibians.

More specifically, frogs.

There are now over 1,800 threatened amphibian species. At least 168 species have gone extinct in the last two decades due to factors such as habitat loss, water pollution, disease, climate change, and invasive species. Additionally, many areas in the U.S. have recently experienced severe drought, and England is currently experiencing its worst drought in decades.

Many frog species depend on ephemeral (temporary) water sources for breeding since they don’t support fish that would eat the eggs and tadpoles. If the ephemeral pools dry up before the young amphibians have time to metamorphose, or if there isn’t enough rain to create pools in the first place, it can result in a missed generation… and a fragile future for frogs.

Poison Dart Frog Sitting on a Leaf (Photo: MoleSon2, Creative Commons license)Kermit the Frog spoke from experience—it isn’t easy being green… or yellow, or red, or black, or blue.

Frogs are essential to the health of wetland, riparian, and coastal ecosystems. Tadpoles feed on algae, preventing blooms that can reduce oxygen levels. Frogs consume millions of insects each year, including mosquitoes and ticks carrying diseases that threaten the health of humans, their companion animals, and livestock. A wide variety of wild mammals (raccoons, opossums), birds (herons, hawks, geese), and reptiles (snakes) rely on frogs as part of their diet.

April 28th was the 4th Annual Save the Frogs Day, established to raise awareness and funds for amphibian conservation. Since many frog species are comfortable living in cities and suburbs, I thought I would pass along suggestions for homeowners who would like to offer some hoppin’ hospitality, courtesy of yesterday’s event organizers:

1.    A Wet Welcome Mat

Fall and spring are the best times to create a permanent oasis for frogs. Kits are available at many garden and home improvement stores, or simply use a container or dig a hole that is deep enough (at least 1 foot at one end) and line it with sand or a flexible plastic liner before adding water.  Keep in mind, you must provide a sloped ramp so the frogs can get out easily.  Slope the liner or build one out of rocks to gradually allow the frogs to get to ground level or out of the pond. (Some nurseries also have floating devices for swimming pools that can allow amphibians who might jump in a way out.)

Don’t clean the water. In fact, add floating plants such as lily pads or leaves to provide cover. Refill slowly and carefully if water levels get low.

Don’t put fish in your pond, as they will munch on your tadpoles and frogs.

2.    Shade & Shelter

Place your pond in a shady spot, preferably surrounded with native plants to attract a tasty bug feast of ladybugs, bumblebees, and other pollinators to also help beautify your yard. You can stack some rocks or turn over a half of a flowerpot beside the rim of the pond to give your frogs a place to sit and eat their lunch as it flies or crawls by.

glass frog (Photo: Josiah Townsend, Creative Commons license)3.    Go Organic

Don’t use pesticides or weed killers. Amphibians absorb water—and any chemicals in it—through their skin. Pesticides and weed killers can run off from land into water and can be lethal to amphibians. Certain weed killers also can alter hormones, changing male frogs into females and reducing the potential of frogs to perpetuate thriving populations.

4.    Patience, Grasshopper

Don’t be tempted to relocate frogs from other areas or stock your pond from pet stores. You may introduce diseases or invasive species and domestically raised frogs will not necessarily adapt to wild habitats. If you build it, frogs will come.

5.    Look & Listen

Become a frog watcher. You will appreciate these wonderful animals more if you can see them in action, and you can help their conservation in the process. The National Wildlife Federation’s Wildlife Watcher program allows citizen scientists to contribute to a growing database of North American wildlife, learn about the animals living in their region, and build a printable checklist of sightings.

.

* Although the focus of this post is frogs, wild birds still face many challenges and threats to their long-term survival. You can check out one such hazard here. Others will be addressed in upcoming NDN posts.

.

Life is better when you have Next-Door Nature—click the “subscribe”  link in the upper right-hand corner of this page and receive notifications of new posts!
© 2012 Next-Door Nature—no reprints without written permission from the author (I’d love for you to share my work; all you have to do is ask). Thanks to these photographers for making their work available through a Creative Commons license: [from top to bottom] Jackie Dougan (Pacific tree frog in rose); sarowen (green treefrog); Sascha Gebhardt (poison dart frog); ucumari (bullfrog); Josiah Townsend (glass frog).
arctic fox by emma j bishop cc

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

.

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 much debate. The question is 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.

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 are too exhausted to fly. Can’t fly? Can’t feed. It’s 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

.

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

.

.

There’s nothing quite as invigorating as 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!
© 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).
wood frog

The wood frog has a large North American range (Photo: Garrett and Kitty Wilkin, Creative Commons license)

.

My mole Tboy (that’s spy, not insectivore) tells me Valentine’s Day has had its intended effect on the wood frog population in southwestern Virginia. On February 18th the first early-bird male appeared at a nearby pond, floating patiently and quietly. Four days later, 50 guys had found their way to the gene pool and were warming up for karaoke and the start of happy hour. Any time now, the ladies will arrive and that joint be jumpin’!

The watering hole has been silent for the last few months. Winter is a time for amphibians to lie low. Really low. Aquatic frogs hibernate on or partially buried in the mud at the bottom of ponds and lakes. Terrestrial frogs, including the wood frog, hibernate on land. Some burrow down below the frost line, but wood frogs are not adept diggers so they seek out crevices in rocks, crawl beneath a log, or just huddle in the leaf litter.  These hibernacula don’t always make for a cozy inglenook. When the temperatures drop below freezing, so do the wood frogs. But not to worry—wood frogs have what it takes to best Old Man Winter.

Antifreeze.

No, I’m not talking about well drinks. A high concentration of glucose keeps the frog’s vital organs from freezing, so even though the animal stops breathing and doesn’t have a heartbeat, it’s not dead. As soon as things heat up again, the frog thaws and life goes on.

wood frogs in amplexis

Wood frogs in amplexis—male is on top (Photo: Richard Bonnett, Creative Commons license)

The wood frog club scene is cool. That’s because it usually begins in January or February, sometimes before the ice has disappeared from vernal reproduction pools. The whole rave lasts for about two weeks. A female steps onto the dance floor—I mean into the water—and a male grabs her and holds on tight. The process is called amplexis. That’s Latin for embrace. Yeah. Kind of like the way sumo wrestlers embrace.  Because once the male has her in his arms, he’s not letting go without a lot of… persuasion. Sometimes not even then.

wood frog egg massesThe process is highly competitive and not without hazards. “Satellite” males hang out beyond the water’s edge so they can grab a gal while she’s in transit. In this way, he avoids jostling with the boys at the pool while also scoring a ride to the party. Also, male wood frogs are stimulated by movement so they’re not always discriminating about who they grab. Sometimes they grab the wrong species of frog, and sometimes several males will grab the same female. This can cause her to be squeezed to death or drown.

But, assuming there aren’t any bar brawls, the female will lay large masses of 1500+ eggs, choosing a site where they receive sunlight and protection from predators. When she releases her eggs, the male—who has been waiting for this opportunity and is now in the perfect position—fertilizes them with a sperm-containing fluid and soon the eggs begin to develop.

wood frog metamorphosing

Eventually, the tadpoles hatch and begin their metamorphosis, absorbing the nutrient reserves in their tails to fuel their makeover.

wood frog metamorphosingTime to head for the forest and get on with the serious business of making a living. Last call! (Until next year, that is).

.
.
Start your day with a little Next-Door Nature—jump to the “subscribe”  link 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. Egg mass photos by Richard Bonnett; metamorphose photos by Brian Gatwicke. Thanks to all the photographers featured in this post for making their photos available for use under a Creative Commons license.

NDN Archive

Enter your email address to follow this blog and receive notifications of new posts by email.

Join 329 other followers

%d bloggers like this: