Blinded by the light

black-and-white warbler (Photo: Friends of Mount Auburn, Creative Commons license)

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

.[This post from March 2012 bears repeating as we enter the Spring migration season.]

I’ve never been much for following trends. I’m more of a swim-against -the-current kind of gal. For example, I wrote this post while flying north-to-south across North America on a Delta jet, while at the same time millions of migratory birds were flying south-to-north along ancient sky routes.warbling vireo (Photo: Eric Bégin, Creative Commons license)By the time I get back home to southwestern Virginia there’s a good chance that wood-warblers will already be there, including one of the more easy-to-identify species, the black-and-white warbler (Mniotilta varia). And it shouldn’t be too long before blue-gray gnatcatchers (Polioptila caerulea) come back to my neighborhood. How do I know this? I’ve been using a great resource to help me figure out what to watch for—The Cornell Lab of Ornithology provides a wealth of information, including real-time bird migration reports and forecasts.

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

At night, migrating birds seem to be strongly attracted to artificial light and once inside the neon and fluorescent glow they’re reluctant to return to the darkness. High-rise glass and light are a deadly combination for these travelers—those that don’t collide with the buildings fly around and around as if caught in a sci-fi tractor beam until they drop from fatigue.blue-gray gnatcatcher (Photo: Jerry Oldenettel, Creative Commons license)In some cities, bird-loving volunteers organize rescue teams who arrive before sunrise to beat gulls, free-roaming cats, raccoons, coyotes, and others to the survivors. The injured are transported to wildlife rehabilitators for care, the dead are collected and counted.  The Chicago Bird Collision Monitors have reported finding an average of 5,000 birds on the streets and sidewalks during the annual spring and fall migrations. In Toronto alone the Fatal Light Awareness Program (FLAP) has documented bird-building collisions for over 140 species.

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

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

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

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

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© 2012 Next-Door Nature—no reprints without written permission from the author (I’d love for you to share my work. Just ask.). Thanks to these photographers for making their work available through a Creative Commons license: Sandy Selesky, Friends of Mount Auburn (black-and-white warbler); Eric Bégin (warbling vireo);   Jerry Oldenettel (blue-gray gnatcatcher); and Joe Penniston (downtown Chicago at night).

No particular place to go

snail

Snails are gastropods–a word that translates as “stomach-foot” (Photo: Sally Crossthwaite, Creative Commons license)

.[reprint from March 2011]

Back when I lived in a large apartment community in this southwestern Virginia college town, I stepped onto the sidewalk one morning for a pre-breakfast stroll with my terrier-boy Dash, and saw a shimmering calligraphy on the concrete up ahead. Living in close proximity to undergrads had taught me to watch my step on Monday mornings… but this didn’t look like party residue.

Since it resembled writing, I thought for a moment it might be chalk—a message decipherable only by Greeks (the collegiate variety, not the folks in Athens)— but that didn’t explain the silvery quality of the text.

Finally, I drew close enough to solve the mystery. It wasn’t writing at all. The weather had finally turned warm enough, temporarily, for the local gastropod to take a stroll along a slime trail.

Wait… can you stroll when you have no legs and only one foot?

Stroll, stride, saunter… call it what you will. Snails get from point A to point B by gliding along a secreted track of mucus that hardens into a kind of Slip ‘n Slide® when exposed to air. The animals ride waves created by a band of muscles that travel along a foot that spans from the tail to the head. Surfing the slime they wander over roadways, through the woods, and up the walls of grandmother’s house or any other structure in their path.

snail trail

Snails secrete a mucus trail that serves as a kind of slo-mo Slip ‘n Slide® (Photo: Krstnn Hrmnsn, Creative Commons license)

Progress appears painfully slow to bipeds and quadrupeds, but the meandering trails suggest snail excursions are all about the journey, not the destination. You have to admit, they never rush—unlike many of their harried human neighbors.

Of course, it’s a smaller world for some. An average speed of 0.03 mph must be fast enough for a garden snail to get where s/he needs to go (snails are hermaphroditic, meaning they have both male and female sex organs, so s/he is particularly apt here).

Before you dismiss the lowly snail as too pedestrian to warrant admiration, you should know that the National Science Foundation supported a research collaboration between the University of California at San Diego (USA) and Stanford University (USA) to better understand the locomotion of snails and slugs, their shell-less cousins. The goal was to create robots that mimic snails, propelling themselves up and down walls, along ceilings, and across other challenging surfaces.

An examination of the mucus trail has proven fascinating as well. When common periwinkle snails are traveling along a vertical surface, the secretions have more adhesive qualities than when the animal is moving along a horizontal surface; the chemical structure of the mucus changes depending on the demands of the route.

But wait—there’s more!

A study by researchers at the University of Sunderland (UK) found that snails conserve energy by reusing slime trails. They will retrace their step to return to a previous resting site—a much safer strategy than hoping to stumble on an appropriate new location in time to avoid the dehydrating rays of the sun. Snails will also follow the trails of their cohorts to find dinner and a date. Essentially, they’re playing follow-the-leader.

So maybe a snail’s life is filled with fun and games. And wouldn’t you just love to see a group of gastropods do the Hokey-Pokey?

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© 2011 Next-Door Nature— no reprints without written permission from the author.

Like cats… and dogs

red fox

The red fox is a canine with many cat-like characteristics and behaviors (Photo: Matt Knoth, Creative Commons license)

.[Reprint from March 2011]

Gazing blearily through coffee steam, a ghostly figure wafting through the early morning haze caught Lisa’s eye. “At first, it was just a ginger-orange and white shadow, and I thought, “Oh, no… another stray cat.”

The specter became more substantial as it moved closer.

“I saw that it wasn’t a cat after all. It stopped at the edge of my patio and began to watch me. There we sat, two redheads—one natural, one augmented—staring straight into each other’s eyes.”

An understandable case of mistaken identity. The red fox (Vulpes vulpes) has some strikingly feline features: a sleek, slender-boned physique; long, sensitive whiskers; flexible feet with partially retractable claws on the front paws; thin, dagger-like canine teeth; and a tail that accounts for 1/3 of the animal’s total length… it all contributes to the illusion.Add to that eyes with vertically slit pupils and you start to understand why the red fox is known as the “cat-like canid.”

Their hunting strategy is more felid, too. Canines tend to rely less on stealth, often hunting in packs using a tag-team approach to run down prey.  Cats, with the exception of African lions (Panthera leo), are solitary hunters who stalk and ambush prey with an explosion of speed. Canids are relay runners; felids—and foxes—are sprinters who dispatch dinner with a quick, sustained bite, in contrast to the multi-wound or bite-and-shake method employed by most canines.Biologists suggest that the behavioral similarities between foxes and cats could be the result of convergent evolution: the development of an identical trait in unrelated lineages. Comparable adaptations, they explain, arise when species occupy similar niches—insect, bird, and bat flight are commonly sited examples. Foxes and small felines target similar prey, so one should not be surprised that analogous hunting strategies evolved in these species.

Seems reasonable enough… but it’s harder to explain some of the V. vulpes‘ other felid behaviors. Their young hiss and spit like kittens, while adult vocalizations include cat-like shrieks and mewing cries. And then there’s the “lateral threat display.” You know it as the classic Halloween scaredy-cat pose—back arched, fur erect. See it and you immediately think, “cat,” not “dog.”

We humans like categories. You’re hip-hop or honky-tonk, freak or geek, fact or fiction, apple or orange. Pick your pigeonhole, please, and kindly stay in it.

So what are we to do about a creature who refuses to comply with our “either/or” worldview?

If you’re an urban wildlife enthusiast, you smile and shake your head in wonder at the boundless diversity of this bright blue gem of a planet, and your luck at having landed on it.

If you’re a taxonomist, you lay awake at night, grinding your teeth.

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© 2011 Next-Door Nature—no reprints without written permission from the author (I’d love for you to share my work. Just ask first.). Thanks to these photographers for making their work available through a Creative Commons license: Matt Knoth (cover); Dave C (eyes); Bernard Stam (hunting); and Dave C (napping).

© 2011 Next-Door Nature— no reprints without written permission from the author.

Prodigal sons (and daughters)

next-door nature, mountain lion, cougar, dispersal, Midwest

Cougars are one of several predator species returning to historic ranges, even when they include highly developed areas (Photo: Wayne Dumbleton, Creative Commons license)

[Reprint from 2012]

Midwesterners are welcoming the return of some long-absent natives.

On second thought, “welcoming” is probably an overstatement… because just as in the famous biblical parable, not everyone is thrilled about this reunion.

A rigorous statistical study to be published in a 2012 issue of the Journal of Wildlife Management confirmed the presence of 178 cougars (Puma concolor) in the Midwestern U.S. states of Missouri (10), Nebraska (67), North Dakota (31), Oklahoma (12), South Dakota (11), and Texas (12). Single incident reports were documented in Arkansas, Illinois, Iowa, Kansas, Louisiana, Michigan, Minnesota, and Wisconsin.next-door nature, cougar, mountain lion, historic photo, market huntingOnce found throughout North America, from the Canadian Yukon south to the Chilean Patagonia and all 48 contiguous United States, cougar populations dropped precipitously over most of their historic range following European colonization of the continent. The 19th and early 20th centuries, in particular, were hard times for all wild predators. Eradication programs aimed at protecting livestock interests were common. Bounties for cougar pelts, combined with sport hunting and a reduced prey base, lead to extirpation of the species east of the Rockies, with the exception of a small subspecies population in Florida (the Florida panther, Puma concolor corryi).

You’ve heard of a coat of many colors? How about a cat of many names? Cougars are almost interchangeably known as mountain lions and pumas, but regional variants include catamount, panther, painter, ghost cat, screamer… and that’s just the English nomenclature.The cougar has had more than it’s share of scientific names, too. Originally considered the largest member of the Felis clan, a genus that includes both the domestic cat (F. catus) and the somewhat larger jungle cat (F. chaus), in 1993 taxonomists created a new Puma group based on similar genetic structure and composed of two members—P. concolor and P. yagouaroundi, the much smaller jaguarondi, found in Central and South America. Another homecoming of sorts, I guess you could say, although whether the members are happy about their new blended family is anyone’s guess.

As the forth largest of all the world’s cats, adult cougars reach shoulder heights of between 24-35 inches (60-90 cm), nose-to-tail lengths of between 6.5-8 ft (2-2.4 m, females and males, respectively), and average weights of 100-150 lbs (42-62 kg; females and males, respectively).  It’s interesting to note that the closer a cougar lives to the equator the smaller it will likely be; the largest cougars are those found closest to the poles.

The species gets its name from the Latin word for “plain” or “one color” and that’s generally true for individual animals (as long as you ignore the lighter belly, throat and chin). At the population level there’s significant color variation, from golden to silvery-grey or even coppery-red. Cougar kittens don’t start out concolor—they are spotted with ringed tails but these markings fade as the youngsters mature.next-door nature, cougar, mountain lion, dispersal, historic range, midwestAdult cougars have a sleek but muscular physique and are able climbers and strong swimmers, with exceptional leaping and powerful sprinting skills. Despite their speed, these cats are typically ambush predators that quietly stalk and then, if possible, drop silently down onto prey from above, breaking the neck or delivering a suffocating bite.

Cougars are obligate carnivores, which means to survive most of their calories must come from meat. What’s less important is whether the main course is mouse, squirrel, rabbit or raccoon, mutton, venison or veal. This failure to discriminate between wild game and domestic livestock has resulted in a long and bitter feud with ranchers that continues to this day.

The 1960s, however, were witness to a sea change in American attitudes toward the environment in general and predators specifically—at least in the urban and suburban areas that were rapidly becoming home to a majority of citizens. Public pressure to change management policies created greater legal protection for cougars and their numbers began to increase. Over subsequent decades, pressure to disperse has obviously increased as well, as western cougar habitat reaches carrying capacity.

Which brings us right back to where we started, with cougars recolonizing the center of the continent. They use what researchers call a “stepping stone” pattern. Young animals say goodbye to Mom (male cougars are absentee dads) and go looking for adventure. Travel the highways and byways, stop at an interesting locale, scout out dating and dining options then move along. Sometimes quite far along… as was the case with a male cougar who made it to Connecticut before being hit and killed by a vehicle.  Leaving home is what most young mammals, including humans, are programmed to do. I’m as good an example as any, having dispersed from Missouri at 21 to explore all three North American coasts and beyond.
next-door nature, cougar, mountain lion, dispersal, midwest
Cougars may have returned to their old stomping grounds but don’t expect fireworks or any other hoopla. As a native who left the area and has returned many times (although never to stay) I can assure you this homecoming will be a low-key affair.

We Midwesterners don’t like to call attention to ourselves, you know.

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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:  Wayne Dumbleton (cover); USFWS/Public Domain (historic photo of a market cougar hunter); Anthonut (profile); Susan Shepard (climbing down); NaturesFan1226 (sharpening claws).

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).

Nutcracker suite

cardinal-grosbeak-crossbill

No, not Tchaikovsky. These are avian nutcrackers (left to right): northern cardinal, rose-breasted grosbeak, and red crossbill. (Photos: ehpien, Conrad Kulper, and Eugene Beckes, Creative Commons licenses)

[A seasonally appropriate reprint from December 2011. New posts are coming for the new year, I promise.]

Ever wonder why hens’ teeth (and any other kind of avian teeth for that matter) are rare? It’s because teeth are heavy. That’s a problem if you live life on the wing but can’t use a knife and fork to cut your meals up into easy-to-swallow morsels.  A bird’s beak (aka bill) is an adaptation to flight that serves most of the same functions choppers handle in Earth-bound creatures… but without the high metabolic cost of carrying around a set of pearly whites.

Bird Beaks by Shyamal and Jeff Dahl, CC

Figure A. Beak shape and size offers a clue as to what the owner likes to eat.

The beak is a sheath of tough skin on the upper and lower mandibles. Wild birds exploit a wide array of feeding resources and niches, and they are aided in this task by a startling diversity of beak morphology (see Figure A). For example, nectarivores (nectar-eaters), including hummingbirds, usually have long, straw-like beaks that reach deep into flowers. Insectivores (insect-eaters) tend to have narrow, slightly curved beaks that can reach into the small crevices where their prey try to stay out of sight. Piscivores (fish-eaters) have a sharp hook, serrated edges, or both, that help them hold on to their slippery supper. Some of the most distinctive beaks, though, belong to nutcrackers.

The northern cardinal (Cardinalis cardinalis) is a familiar and popular resident of cities and suburbs, possibly because it’s so easy to spot and identify. It’s so popular, in fact, that seven U.S. state legislatures have chosen this species to be their avian poster child.  At  8½—9” (21—23 cm) from jaunty crest to tail tip, it’s a medium-sized songbird with ahim and her cardinals by Steve Wall cc stereotypic nut- and seed-busting beak—short, stout, and cone-shaped. I like cardinals as much as the next person—I’m from St. Louis, after all, where you can walk down any street in the whole town and know you’ll see someone wearing a shirt adorned with a bright crimson bird perched on a baseball bat. But my affection is somewhat tempered by the fact that their beaks work equally well at crushing seeds and human skin, as I can personally attest. Who would guess you could have empathy for a sunflower seed?

The rose-breasted grosbeak (RBG, Pheucticus ludovicianus) is slightly smaller than a cardinal (7—7½” or 18—21 cm) with a pale, conical but more zaftig bill… a chestnut to the redbird’s hazelnut. Of course, it’s natural for kin to resemble one another, and the RBG is, in fact, one of 17 species known as the “cardinal-grosbeaks.”* Grosbeak—from the French grosbec (gros thick + bec beak) is a bit of a misnomer for this striking black and white bird with a cherry cravat (the females prefer a more sedate, sparrow-like wardrobe). Compared to the schnozzes sported by some members of the Cardinalidae clan, the RBG has a proud but modest snoot.

Although not as common as its stop-light colored cousin, human development—and the fire suppression policies that accompany it—have caused forests to sprout where once only grasses grew, allowing the RBG to expand its breeding and migration range westward (although the Rocky Mountains have proven to be a tough habitat nut to crack).  They’ve become a more frequent visitor to backyard bird bistros, where they like to snack on safflower, cracked corn, and black-striped sunflower seed. Insects and fruit are part of their diet as well, but seeds account for the majority of their calorie intake, especially during winter months.

As the name suggests, red crossbills (Loxia curvirostra) are true specialists. At first glance you might think this is a bird in dire need of an orthodontist, but that oddly shaped bill allows them to force open conifer cones and extract the tasty nutmeat inside. The muscles that allow birds to bite down are stronger than the ones used to open their beaks. But unlike cardinals and grosbeaks, who can clamp down with great force on tough-hulled sunflower seeds (and tender, well-meaning human hands), the crossbill can wedge the slightly opened tips of its bill between the scales of a tightly closed pinecone and then bite down, pushing the scale up to expose the kernel.

The red crossbill is extremely dependent on conifer seeds—wildlife biologists refer to animals whose very existence depends on a narrowly-defined habitat or food sources as obligate species. Most granivores (seed-eaters) start their lives eating protein-rich insects, making a dietary change once they reach adulthood, but crossbills feed on seeds from nest-cradle to grave. Of course, there are risks associated with being a specialist… we’ve all been warned against “putting all your eggs in one basket.” But as long as long red crossbill by eugene beckes ccas you follow the advice of Mark Twain and “watch that basket!” there are benefits as well. For example, red crossbills can raise young any time of the year—even during winter—as long as the cone crop is abundant. I guess some nutty looking adaptations are really quite useful.

The Clark’s nutcracker (Nucifraga columbiana) has also used the reliable conifer nut to expand its breeding season. But this member of the Corvidae family (jays and crows) takes the idea even further. It is a hoarder, storing surplus pine, spruce, and hazelnuts. They actually have a special pouch under their tongues which they use to clark's nutcracker by Jamie Chavez cccarry seeds over long distances. A single Clark’s can hide as many as 300,000 pine nuts over the course of a year, and they use this cache crop to feed themselves and their nestlings. Research has shown they have a phenomenal memory and can find most of the seeds they’ve stashed, even months later.

Most… but not all; some of the hidden seeds germinate, re-establishing the bird’s favorite trees in areas cleared by fires or logging operations. It’s a sustainable harvest practice, however accidental, and a form of basket-watching that would make Samuel Clemens proud.

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* The grosbeak taxa is a conglomerate of distantly related songbirds known as a polyphyletic (“of many races”) group that we’ll explore in greater detail in future NDN posts.

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© 2011 Next-Door Nature—no reprints without written permission from the author. Thanks to the following photographers for making their work available for use through a Creative Commons license: ehpien (northern cardinal); Conrad Kulper (rose-breasted grosbeak); Eugene Beckes (red crossbill); Steve Wall (male and female cardinals); Trisha Shears (2nd red-breasted grosbeak); Eugene Beckes (2nd red crossbill);and Jamie Chavez (Clark’s nutcracker).  Figure A was made available through WikiMedia by Shyamal and Jeff Dahl.  Bird song mp3s files are in the public domain.

Stick in the mud

red-eared slider by Charles Lam cc

[This reprint was originally published on January 14, 2012.] 

Shorter days and Jack Frost nipping at your nose means it’s the start of the serious season, filled with snowplows, tire chains, and 10-pound sacks of clay litter that will never feel a kitty’s caress.  In many parts of the northern hemisphere, it’s a long slog through snow, sleet, and freezing rain to get from December to daffodils.

Understandably, we look to Nature for role models. Native people aren’t unique in their ability to draw a connection between human and non-human animals—Madison Avenue is especially canny at choosing charismatic creatures to impersonate our enviable and endearing (or at least humorous) characteristics.  Particularly at this time of year, when mercury can’t seem to bootstrap its way past 32°F, you’ll find a lot of furry sales reps pitching warm and cozy wares in magazines and newspapers, on television and online. I assume the general idea behind this trend is that raw, gray days bring out the hibernator in all of us mammals.

Not to split hairs, but that’s not technically correct. Humans don’t hibernate, but we do go through some behavioral changes at this time of year, at least so far as jobs, school, and the other routines and rituals of modern life allow. times square blizzard by Asterio Tecson ccFunny, how those cold weather coping strategies make humans look strangely reptilian. Just watch—next time the Weather Channel predicts a cold front, with or without a “wintery mix,” check out all the necks and heads tucked back into Gortex shells, peeking out from fleece hoodies, swaths of scarves, and turned up coat collars as they hunch toward the warmth of home. Do you think they look more like bears, or turtles?

Now, there’s a bit of Class warfare at play here because homeothermic (body temperature largely uninfluenced by the surrounding environmental) hominid mammals aren’t often flattered by comparisons to scaly, poikilothermic (body temperature influence by the surrounding environment) cold-bloods. Knowing this, and well aware that you, dear reader, will read my claim with considerable skepticism, I’ve got an example ready to back me up: a familiar and easily identifiable semi-aquatic turtle called the red-eared slider (Trachemys scripta elegans).Even nature neophytes will immediately recognize this species, a common resident of lakes and ponds in urban and suburban parks, as well as pet stores. Shell, legs, head and tail are inscribed with stripes and nested ovals of green and yellow, the “elegant script” referenced in its Latin name (although the vibrant colors do tend to fade somewhat with age and a thick coat of algae).

The red “ear” on either side of the head distinguishes the slider from all other North American turtle species and allows for a quick and definitive ID as they sunbathe on stones and logs. “Quick” being the operative word here; sliders don’t hear well, but they are very sensitive to vibrations that alert them to the presence of potential predators, and they can slip back into the safety of the water with surprising speed.

In the wild, the slider’s life cycle begins with courtship and mating as early as March or as late as July, depending on the region and the weather. Subsequently, the female heads for dry land to deposit a clutch of eggs, excavating with her hind legs to create a nest in the soil. Then she turns for home with nary a backward glance, and the turtles-to-be she leaves behind are on their own from that point forward. Two or three months later, depending on the average ambient temperature, hatchlings emerge from the nest and set out to conquer the world.

Most of them don’t make it past the first year—such is Testudine life… and death. Those who live to see their 2nd birthday, however, can reasonably expect a couple decades of celebrations, getting bigger with each passing year (females reach 10-13 in (25-33 cm), while males max out at 8-10 in (20-25 cm)).

In addition to predation, freezing temperatures are one of the biggest barriers to longevity that young turtles must navigate in the wild (HA! I’ll bet you thought I’d lost my original train of thought on winter and hibernation, didn’t you?).  No one expects to see a slider in a snowstorm, so it’s natural to assume they use sleep as a survival strategy.  Hey, it works for two of the most diverse Orders on Earth—Chiroptera (bats) and Rodentia (rodents)—so why not?sunning r-eared sliders by Alan Vernon ccBut reptiles take a different road.

Brumation is a period of decreased activity, but it doesn’t involve the extreme metabolic changes that occur during hibernation. ‘Round about October, as temperatures dip below 50°F, sliders begin to settle in at the bottom of their preferred body of water, or in some cases under stream banks and tree stumps, and just… hang out. They’re less social, they move a little more slowly, sleep a little later, watch more television (I’m sure there must be a turtle equivalent), and generally feel lethargic and unmotivated. On warmer days, they’ll drag themselves up from the depths to stretch their limbs, have some lunch, and catch some rays with a few friends… but as soon as old Sol goes into hiding they follow suit, retreating into their shells to become stick-in-the-muds until spring.

Social commentators have come up with any number of marketable catch phrases to describe the human desire to turn our backs on a less than hospitable world—cocooning, burrowing, vegging out, even hibernating. The admen (and women) may argue that it doesn’t have the same sizzle, but what we’re really talking about here is brumating.

Sound like anyone you know?

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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: Charles Lam, Asterio Tecson, Jim, the PhotographerAlan Vernon, and Jack Wolf.

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).