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So far Randy Fry has created 49 blog entries.

Farewell to the Gray Coast

I love these woods when they’re wet.  A thunderstorm crashed through last night, and the pine duff is soaked, drenched through, a glistening, springy, cinnamon-colored cushion as big as the whole forest.  My awareness reaches, unsatisfied, beyond my body as I run the trails, and I am imagining the give of the wet carpet under my bare palm.  My mental hand reaches out and touches the rough water-darkened bark of oak trees as I pass by, shakes a silver spray of droplets from a spun festoon of lace lichen, reaches into a puddle and feels fine clay mud under half an inch of icy water, while my legs go on pounding, my lungs go on breathing.  The air is cold and clean, and it’s starting to rain again, pelting against my chest and soaking the tops of my aching thighs, but I’m not cold, I’m high.  My burning muscles vault me over a new windfall, and a chaos of fallen foliage showers me with water.  At the top of a rise I throw my tired head erect and look out, far out, over the misty ridges, under the rainclouds, and there it is, the Monterey Bay, gray within gray within gray.  Five thousand feet deep where I’m looking. 

 

I wrote those words in 1992 and my love for this peninsula is undiminished.  Susan and I have hiked its trails, kayaked its waters and run its marathons.  We have walked the fields of lupines in sunny springtime meadows, and hammered out training runs through icy rain and hail on Big Sur ridge tops.  We have powered our kayaks through the angry waters off the Point Lobos headlands where Robinson Jeffers wrote brooding pieces about the gray coast.  We have crossed the Monterey Bay, we have hung out on the tops of the canopies of the great kelp forests, and we have poked around in networks of sea caves where the water beneath us is under-lit by green light from mysterious submerged portals, and the only sound is the slow suck-and-draw of the breathing of the great ocean.  We have explored this place completely and intimately, as lovers should.

On Thursday we leave it.

The place we are going would be called, by most reasonable definitions, paradise.  We will be on a Caribbean coastline in Mexico.  We will be walking among Mayan ruins, and kayaking turquoise waters without wetsuits.  The birds will be wild, loud and colorful, with long tails or absurd beaks, and there will be monkeys in the jungle canopy and tropical fish in the estuaries.  We will have a whole new ecosystem to learn.  But one never really leaves the Monterey Peninsula.  I know this.  I have been haunted by it before.

Susan and I have sold everything we own that will not fit in a pickup truck.  A lifetime of acquisitions are gone and we have not suffered a moment of remorse.  We will have each other, our dog Rita, two ocean kayaks, and a few boxes.  On Thursday we step on the gas.  Really it is a crossing—there are no beaches, there is no bail-out.  And that’s just the way we like it.

We are the luckiest people in the world, to have each other, and to have this life, and I’m certainly not complaining….

…but God dammit, I’m going to miss this place.

 
 

 

 
Copyright © 2014 Randy Fry
By |2015-08-31T11:15:41-05:00May 1st, 2014|Nature Essays|1 Comment
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Falcons With Mean Streaks

So picture this:  You’re a pigeon.

You’re a pigeon and you’re whizzing along a hundred feet above an open area.  You’re whizzing along and you notice a speck in the sky two thousand feet above you.  You notice a speck and then you notice that it’s dropping toward you.  It’s dropping toward you and when it turns out to be a peregrine falcon, you are so screwed…

If there were some trees or brush to drop into you might be okay, but that’s not where peregrines hunt.  There is nowhere to fly to and nowhere to hide, and it seems so unfair, because you’re a pigeon, for God’s sake, you’re one of the strongest fliers on the planet.  You can sustain forty miles per hour in level flight, which that peregrine up there couldn’t dream of doing, but even as that thought crosses your mind, the peregrine crosses the hundred mile per hour mark because she’s tucked, she’s in a vertical dive, plummeting at you like a bullet and still accelerating.  You pour it on, but as you’re approaching your top sprint speed of sixty miles per hour the peregrine breaks a hundred and fifty.  Nictitating membranes shutter across her eyes to shield from the screaming wind.  You see a distant grove of trees but you know you won’t make it.  The peregrine breaks two hundred miles per hour.  At two-forty she opens her wings ever so slightly and starts to pull out of her dive behind you, making a sound like canvas ripping, pulling twenty-seven G’s and briefly weighing fifty-nine pounds, and then she flashes into you still doing almost two hundred miles per hour, but she doesn’t grab you. 

She hits you.

*          *          *          *

The pigeon is killed instantly and painlessly, though that’s not always the case with a peregrine kill.  The impact is like being hit by a high-speed projectile and it shatters the spine at the base of the skull.  As the pigeon tumbles lifeless through the air, the falcon slows to a sane speed, circles around with a couple of flaps, and snags him in mid-air, then flies off to find somewhere safe to eat.

Susan and I chat about cheery things like this all the time, and as we were remarking over cocktails last night about how amazing peregrine falcons are and how much it must suck to be a pigeon, I brought up that remarkable technique they have of hitting their prey instead of grabbing it, and Susan asked a great question.  The question went like this:

Hit it with what??

With their head, for God’s sake?  With their breastbone?  What could they possibly hit it with?  They don’t carry a club or a mace.  How the heck do you hit something—at two hundred miles per hour—without both of you becoming lifeless puffs of feathers?

I had no clue, and Susan doesn’t let me make stuff up, so I had to dig into this a little.  I managed to find it, and of course along the way I learned some amazing stuff I hadn’t known about peregrine falcons, so a Ranger Randy article was warranted.  Here you go:

First of all, to answer Susan’s question, they hit them with—if you’re ready for this—a clenched foot.  I kid you not.  They hit them with their fist.  At least that seems to be the prevailing opinion, though there’s still argument.  One fairly auspicious scientist (and falconer) named Tom Cade absolutely insists that they strike with an open foot, even claiming that they rake the rear talons across the back of the bird, but most of the world including me finds that hard to picture.  I just can’t imagine a falcon retaining  possession of all his toes for very long if he went around doing that.  (It’s delightful that we still don’t know this conclusively—falconry has been a sport for four thousand years.)

But what absolutely flabbergasted me was that number up there—that three-digit one.  That’s a confirmed number.   There’s a guy named Ken Franklin in the San Juan Islands in Washington state who is a falconer and a pilot and a skydiver and the husband of an ornithologist, making him probably the only person on the planet who could have concocted a way to clock a peregrine in a dive.  He affixed a tiny altimeter to a feather shaft on the rump of his female peregrine falcon and took her up in a light aircraft to 15,000 feet, then falcon and falconer both jumped out of the plane.   He then dropped what falconers call a lure, which is a leather-covered weight with some feathers involved so it looks a little like a bird.  The falcon went into her dive, which is called a stoop, and she achieved two hundred and forty-two miles per hour pursuing that thing through the vaults of sky.  (You can watch the Youtube here.)  Now, let me just hazard a few comparisons regarding that number:  That wind speed will peel the skin off an airplane if it has some missing rivets.  The most intense hurricane on record, Wilma, in 2005, only had winds of 185 mph.  My brother Gary is going to take me up flying in a few weeks, and the top speed of the Cessna aircraft we’ll be in is only 188. The closest I’ve come to feeling those kinds of winds was 110 miles per hour.  That was a skydive, and it was a fight to keep my cheeks on my face.

The posture of a peregrine falcon during a stoop has been called hyper-streamlined.  They are a heavy, compact, small-winged bird in the first place, and when they go into their stoop, they assume a perfect teardrop shape, like a tiny torpedo.  I’m not built as well for that kind of thing, so wind resistance held me to a pokey 110 mph, but some physicists did a study testing the flight physics of an “ideal falcon” and calculated that terminal velocity for them is 250 mph at sea level (confirmed by Ken Franklin’s experiment).  At high altitude, they figure maybe 390.

That’s half the speed of sound.

When they kill smaller birds like songbirds they can just overtake them and grab them like any other hawk, but the larger ones they will hit.  They often hit something too large to carry, and in that case they will follow it to the ground and chow down there. If they were only able to stun or disable the bird, they dispatch it with a special adaptation to their beak shape called a tomial tooth, designed to quickly sever the spine.  They have been observed killing birds as large as a sandhill crane, which is a wading bird that stands as tall as your chest.

They prefer not to eat on the ground, though, because they do have their own predators.  Raptors like the golden eagle or some of the larger hawks will drop on the peregrine in their own stoop if they catch her on the ground, and the peregrine is not the fastest bird in level flight.  With the tables turned, she will not be able to escape.  This might explain the mean streak they have where large hawks are concerned.  A peregrine will kill a red-tailed hawk given the opportunity.   The red-tailed is too big for her to kill outright, but the falcon will come streaking through from out of nowhere and break one wing.  The hawk will spin to the ground, crippled, where he will probably die a very slow and painful death by starvation, without even the hope of a merciful killing by another predator.  As Robinson Jeffers says in his wonderful poem, Hurt Hawks, “There is prey without talons.”  This is probably what befell the hawk he writes about.

Peregrines like to hang out on extremely high perches above open areas with little cover, so they’re fond of bluffs above bodies of water.  We have a pair here in Monterey, California who hang out on the “E” of the lighted sign on the top of the Embassy Suites high-rise, above a nice lake with lots of waterfowl.  If there’s not a high perch around they will circle as high as three thousand feet above the hunting ground, so high they’re not even visible to creatures like us.  They have incredible eyesight.  Their eyeballs are huge, they just don’t look like it, because unlike us, only the iris and pupil are exposed.  Their eyeballs actually take up most of their skull, leaving little room for other sundries like a brain.  (That’s also why owls don’t owe their survival to their intellects—a barred owl has a skull the size of a golf ball and two human-sized eyeballs in it.)

Peregrines were once a very successful bird with a world-wide range, but we almost managed to kill them off completely by dumping the “harmless” pesticide DDT into our environment for three decades.  The poison magnified up the food chain and the falcons took a bad hit.  It robbed them of their calcium and the eggshells would all break before the chicks could hatch.  In a rare example of doing something right, we outlawed the stuff in the nineteen-seventies, and peregrine falcons rebounded, and are back off the endangered species list, a conservation success story.  It can be done, when we have the will.

So that’s the news on the peregrine falcon.  Fastest creature on the planet, proud and noble, but also with a mean streak.  Oh, and they’re fastidious:  Before they eat their prey, they pluck it.

Now you know.

 
 

 

 
Copyright © 2014 Randy Fry
By |2017-12-09T07:28:47-06:00February 15th, 2014|Nature Essays|Comments Off on Falcons With Mean Streaks
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Ravens in the Service of the Crown

There are ravens in the Tower of London.

Which may not sound that remarkable, but the reason it’s sort of weird is that ravens (Corvus corax) almost do not exist anywhere else in the British Isles.  They were largely exterminated over a century and a half ago when it was thought that they killed baby livestock.  Ravens cannot do that.  They cannot kill a healthy newborn calf, but they are carrion eaters, and when a farmer would walk out and find a dead baby calf with ravens pecking out its eyes, he would come to the wrong conclusion.  Unjustly accused, the ravens, after co-habiting with the English for many centuries, suddenly, due to some inexplicable turn in public opinion, became pariahs, victims of prejudice, and a great cleansing ensued.  A raven genocide swept across the English landscape, and as firearms became more widespread, their fate seemed sealed.  What saved them is that ravens are corvids, and can learn and teach, and they quickly started avoiding humans, and teaching their young to do the same.  Nowdays, they only exist in the highlands and the outlands, nowhere near human habitations.

Corvus_corax_London
Common Raven (Corvus corax) at the Tower of London
By Philippe Kurlapski,
[CC BY 1.0], via Wikimedia Commons

But a small colony nests in the Tower of London, right in the center of the city, and there is great speculation about how in the heck they ended up there.  The answer is lost to us, but the ravens have become a storied part of English society, because there is a superstition in England which goes something like this:  If the ravens ever leave the Tower of London, the British government will crumble, and a horrible fate will befall all her people.

Taking no chances, the British government clipped their wings.  They can fly a little way, but not far.  There is a full-time ravenmaster at the Tower of London, and a staff to care for them, and the birds are carefully nurtured and luxuriously fed, and are very close to the hearts of the royalty-loving British public.
Administratively, the ravens are enlisted as soldiers in the British army, and each has a leg band with identification, and an attestation card like anyone else in the service of the Crown.  And they can be dismissed for unsatisfactory performance, too.  One was let go for attacking television antennas.  Another was able to fly a short distance away and took up residence in a local pub, and was discharged for conduct unbecoming.

Several decades ago one of them was kidnapped.  He was never found and the crime was never solved, and in the substantial body of English folklore that surrounds unsolved crimes, this one rates right up there with Jack the Ripper.

I saw the ravenmaster interviewed on TV once.  The interviewer politely asked him whether he actually believed this superstition, and whether he was able to take his job seriously.  A philosophical look crossed the fellow’s face.

“Well,” he said, in his charming Londoner accent, “I look a’ it this way:  if the ravens were to leave the Tower of London…and if the British government did crumble…and a ‘orrible fate did befall all her people…I’d have a lot to answer for, now wouldn’t I?”

Now you know.

 
 

 

 
Copyright © 2014 Randy Fry

By |2017-05-24T00:03:07-05:00January 26th, 2014|Nature Essays|Comments Off on Ravens in the Service of the Crown
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The Mind of the Crow

Well, happy holidays, friends, family and fellow naturephreaks!  I hope that you had a good one, and got out on a hike or two in this beautiful, bright winter weather we’ve been having.

Good friend and gifted birder David send us a link to the video below, and you might want to take two minutes and watch it, because it’s pretty astonishing.  It’s a Russian carrion crow (Corvus corone) tobogganing down a snowy rooftop on a plastic lid he has found.  I’m not making this up.  He does it repeatedly, carrying it up the slope each time for the next run.  I have known for a long time that crows are pretty clever, but this one absolutely blew me away, and I decided it was finally time to write an article about corvids.

Corvids (family corvidae) are, roughly speaking, the crows, ravens, magpies and jays, and they are an amazing family of birds.  As I’ve mentioned in a couple of other articles, the owls, our favorite symbol of wisdom, are actually one of the stupider birds.  The corvids are the brilliant ones.  They are the innovators, the problem solvers, the ones who can adapt to anything and handle change at a pace few other creatures besides us can.  And the cool thing is that they’re all around us.  You don’t need to go anywhere at all to see a corvid, and if you pay attention, you’ll see that intelligence shining through.

The stories abound, and I’m going to entertain you with a few of them, but then I’ll look a little deeper, into the reasons that corvids are the amazing birds they are.

Scrub_Jay
Western Scrub Jay (Alphelocoma californica)
By Ingrid Taylar,
[CC BY 2.0]

I’m a cubicle inmate now but I used to have an actual office with an actual window, and one day on a whim I brought in a bag of peanuts and set a few out on the windowsill.  Within two days I had scrub jays (Aphelocoma californica) taking peanuts out of my hand.  Within a week I had trained them to tap on the glass with their beaks to get my attention, because back then I was young and ambitious and there would be the odd moment when I was absorbed in my work.

Our friend Marty was driving behind another car once on a stretch of country road where ground squirrels were working the dirt shoulder, and he saw a crow positioned on a fence post ahead, right above a foraging ground squirrel.  The crow waited until the car in front of Marty was upon them, then he dive-bombed the ground squirrel, startling him out into the path of the car.  Thump-thump.  Dinnertime.  It could have been coincidence, but I have no problem believing it was intentional.  After all, crows have been documented herding sparrows into glass walls to stun them.

If you hang a piece of meat from a perch on a string, a common raven (Corvus corax) will figure out how to pull it up bit by bit, stepping on the string in between so it doesn’t drop back down.  They steal the fish off the lines of ice fishermen the same way if they’re left unattended.

In the city of Sendai in Japan, carrion crows (Corvus corax ) fly into intersections when the light is red and put walnuts in the paths of car tires, to get them crushed.  They started doing this in the 1990’s, and the behavior is expanding into other regions, because crows share information socially, so what they learn moves outward through the populations and also downward through the generations,  and that, it can be argued, could be called culture.  Culture among animals is controversial.  It’s one of those things like tool use, which we would really like to believe is ours exclusively.  But this writer believes that the news is bad, and we’re not as special as we think.

Crows are widely reported to hold funerals.  They stand around a dead flock mate—in silence.

Crows and ravens play.  Play can be defined as structured behavior that brings no material benefit to the animal, and people as auspicious as Sigmund Freud and Carl Jung spent a lot of research time trying to prove that it is exclusively human.  They failed.  Obviously they’d never seen a tobogganing crow (or raised a kitten).  Crows will break off a twig to just the right size and play with it socially in groups (by the way, that also constitutes tool-making), and ravens will even play across species—the ones up north enjoy playing catch-me-if-you-can with wolves, diving at them and veering away just as the jaws snap, for no practical reason anyone has been able to figure out.  The ravens up there will also lead wolves to a dead animal whose hide is too tough for them to break, so that the wolves will open up the carcass for them, which is a behavior that wildlife scientists call manipulation.

Ravens display an ability in communication called displacement, which is the ability to communicate about something which is displaced in space or time—that is, something which is not here, or which is not here now.  This seems commonplace to us but there are only four groups of animals who can do it:  Us, ants, bees, and the common raven.  It was a foundational development in the evolution of human language.  Here’s one way the ravens use it:  ravens mate for life and the pairs are pretty solitary and defend a territory, but the unmarried ones flock, and when one of them finds a nice carrion kill in an area defended by a mated pair, he’ll go back to the roost and muster enough buddies to return, often the next day, and drive the pair away so they can eat.  It’s a behavior called recruitment, and ants do it too, when a dead bug is too big to drag.

Ravens cache their food items one at a time all over the landscape (it’s called scatter hoarding) and can remember dozens of locations, and they rob each other blind, shamelessly pilfering one another’s goodies.  A raven will fly a long way to cache something somewhere safe.  Others will inconspicuously watch, remember, and return later when the owner is not around.  Sometimes a raven will pretend to cache something, then fly off and cache it somewhere else, which proves that they are capable of deception.

RavenMaskl
Ravens are huge in Native American folklore and creation mythology
By Daderot (Daderot) [CC0 or CC0], via Wikimedia Commons

Ravens have been famous for this kind of stuff for thousands of years.  They have a huge presence in folklore and creation mythology, going back at least to the Paleolithic (fifteen to thirty thousand years ago), and are always showing up in Native American stories as clowns, tricksters and mischief makers.  The Bella Bella people of coastal British Columbia believe that Raven created the world for his own amusement, and considered human beings to be the most amusing animals of them all.  Then, for his own amusement, he made all the rivers run only one way, to make it more difficult for us to get around, which I personally think was just plain unkind, but at any rate, now I know who to thank for all those car shuttles I have to set up any time I run a river.

Crow_1024px-Steller's_Jay_Sandia_Peak
Steller’s jay (Cyanocitta stelleri)
By John Fowler, [CC BY 2.0], via Wikimedia Commons

Some corvids are gifted mimics, and use the talent in very clever ways.  A Steller’s jay (Cyanocitta stelleri—another corvid you don’t have to go far to see) can mimic perfectly the beautiful, haunting cry of a red-tailed hawk.  I swear they even throw a little reverb on it so that it sounds like it’s ringing down from on high.  A naturalist friend of ours knows of a stand of trees in Point Reyes in central California where robins stop off on their migration.  At some times of the year there will be ten thousand robins in this grove, and it just ticks off the local Steller’s jays.  So now and then one of them will do a fly-over and let loose a red-tailed hawk cry, and ten thousand robins will rise into the air in a panic.

I was backpacking with my nephews once in Yosemite when I heard the sound.  “Hear that, boys?” said Wise Ranger Randy.  “That’s a red-tailed hawk!”

“Um, Randy…” my brother Byron said out of the side of his mouth, and pointed discretely to a Steller’s jay in a bush twenty feet away.  Damn.  Nailed by the oldest one in the book.

 

*          *          *          *

 

At the University of Washington some years ago, Dr. John Marzluff was trying to convince his friends and colleagues that he wasn’t crazy.  He was being attacked and harassed by crows far more than anyone else on campus.  Even when he was walking in a group, they would attack him and not the people next to him.  The reason this interested him was that he was an ornithologist, and in fact he studied crows, which meant that he spent a lot of time trapping and banding the crows on campus, and climbing up to their nests to band the chicks.  Dr. Marzluff was absolutely convinced that they were recognizing him as an individual, though birds are not supposed to be able to do that.  What he didn’t know was how they were doing it.  Was it his face?  His gait?  His hair color?  His fashion sense?  He did what any scientist would do, and conducted a study.

He went to a dime store and bought two masks, one of a caveman, and one of Dick Cheney.  He started wearing the caveman mask whenever he was doing his crow work.  After a while, he started getting attacked any time he wore his caveman mask around campus.  When he wore his Dick Cheney mask he would not (though it turned a few students’ heads).  When he put the caveman mask on a student and made him walk across campus, the student got attacked (research assistants live tough lives).  He tried wearing the caveman mask upside-down.  An approaching crow would roll over slightly in flight and cock his head, checking out the upside-down visage.  Then he would attack him.

 

*          *          *          *

 

It was amazing news to the scientific community that crows can recognize faces, but they can probably do it because they live with humans, and when you live with humans, quite literally one will feed you and the next will kill you.  And that takes us to the most fascinating part of this yarn, which is the shared history of crows and human beings.  Crows, and probably other corvids as well, have been co-habiting with humans since before we were humans, probably for over eight million years.  And since our intellects didn’t begin their spectacular ascent until about two million years ago, for several million years while crows shared our hunting grounds and encampments with us, our wits were about evenly matched.  Really we co-evolved with crows.  And when our intellects did begin their climb toward humanness, and we began to evolve culturally at a rate far outstripping the glacial pace of genetic evolution, crows had to keep up, and they began to evolve culturally as well, by sharing and handing down information.  When we started building cities, they came with us.  When we invented guns, they moved into the cities in bigger numbers, because guns are not allowed in cities.  As our inventions changed the landscapes and the ways we lived, the crows adapted, and handed down the tricks to their children.  As author John Marzluff says in his wonderful book, In the Company of Crows and Ravens, the more unpredictable we became, the smarter crows had to become.

So that’s the thing:  Our journeys are intertwined.  When you look at a crow, you are looking at a creature who goes way back with you.  You are looking at a creature whose ancestor shared a campsite with your ancestor—and had him outwitted a lot of the time.  You are looking at a creature who, just like us, survived the most harrowing passages of his evolutionary journey by using his wits—by innovating, and learning, and cooperating, and then teaching it all to his children.

Now you know.

 

 

 
Copyright © 2013 Randy Fry

By |2017-05-24T00:03:07-05:00December 28th, 2013|Nature Essays|Comments Off on The Mind of the Crow
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Yellow Jackets According to Yellow Jackets

 

In a mixed conifer forest in the mid-elevations of the Sierra Nevada Mountains in California, a yellow jacket wasp hovers an inch above the forest floor, fanning the pine needles with her downwash, shifting rhythmically back and forth a few times and then skimming to a new spot, checking things out.  She is a queen.  It is spring and she has just emerged from hibernation.  She is stiff from her long, cold sleep, but her flight muscles are starting to warm up.  She circles the trunk of a large ponderosa pine and returns to checking out the pine duff, using all her senses to detect what’s beneath.  She has a job to do:  she needs to find a nest site.

She’s fond of abandoned rodent burrows, but a number of things will work.  She settles on an old ground squirrel burrow, its entrance obscured by fragrant pine needles.

All alone, she goes to work.  She does the small amount of excavating that needs to be done to reopen the entrance, and then builds a small paper comb hanging from the ceiling, just a few dozen cells, and she lays eggs in them.  As she waits for them to hatch, she goes out on forays into the woods, learning the area, and fortifying herself with nectar from some wildflowers.

When the larvae hatch, she feeds and nurtures them, going out on hunting trips and feeding them noshed-up insects she has killed.  They mature quickly into adult wasps.  They are sterile females—workers—but she can create fertile males also, any time she wants, egg by egg.  The new worker wasps hang the next rack of cells beneath the first, and it is bigger, and she lays more eggs.  She has a crew now, and the crew is helping her create more crew.  The hive is bootstrapping itself, from almost nothing.  As the combs grow and the workforce strengthens, she begins staying inside, focusing on reproduction, and staying safe.  The workers around her are capable and armed, and they will stop at nothing to defend her.

The workers range out across the landscape to find food for the growing hive.  They are energetic, inquisitive and aggressive.  They have a lot of mouths to feed, and they don’t go in for subtlety.  They are predators, and they launch a brutal and resolute assault on the local insect population, quickly asserting balance into the explosive springtime hatches of flying and crawling creatures.

But they do not eat the meat themselves.  In fact, they don’t eat meat at all.  They only eat liquidy sweet stuff, like nectar, and now and then some fruit.  What they do with the insects they’ve killed is to feed them to the larvae, who need the protein.  The larvae, in turn, secrete a sweet liquid that keeps the workers fed.  There is no selfishness in this hive—you get fed by giving.  It’s a behavior called trophallaxis, and it’s pretty common in social insects.

As the colony grows, the workers start to fly farther, trying to find enough meat to feed the booming larvae.  When the catch of insects starts to get thin, their scavenging behavior kicks in, and they scour the picnic areas, getting waved and slapped at by slow and lumbering hands.

It’s late summer by now, and the colony is approaching 2,000 wasps.  It is bustling and humming, and their numbers in the woods and the picnic grounds are getting intense.  As the queen starts to wind down her egg-laying, and the larvae numbers begin to taper, an interesting mathematical problem emerges.  There are no longer enough larvae to feed all the workers.  The workers go out and scour the landscape anew, but now they’re not trying to feed the larvae, they’re trying to feed themselves.  Again the picnic area works for them, but this time they’re not looking for meat for the larvae, they’re looking for sweet stuff for themselves.  They’re not after the hot dogs, they’re after the soda pop.

 

*          *          *          *

 

Early fall.  There is a chill in the air, and these creatures do not handle cold well.  Already, some of the workers are dropping, or not returning from their foraging runs.  When the first serious cold hits, the entire colony will perish.  The workers, the handful of fertile males, even the queen who founded the hive, everybody dies—but there is a new queen.  Maybe more than one.  She has been carefully nurtured and generously fed.  She is young, strong and she has reserves.  She has spiraled up on the mating flights with the males, and had her moments of rapture in the sky.  And now, she flies off, all alone, leaving behind her the collapsing colony.  A few weeks from now it will be a scatter of dead bodies and some crumbling paper combs.  It will not be re-used.

She looks for a place to hibernate.  She crawls into a deep crevice in a western black oak tree.  She nestles carefully into her space, and there, with the existence of an entire colony resting on her survival, she shuts herself down and waits for spring.

 

 

 
Copyright © 2013 Randy Fry
By |2015-09-03T09:03:16-05:00October 20th, 2013|Nature Essays|Comments Off on Yellow Jackets According to Yellow Jackets
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Yellow Jackets According to Us

When I headed out with the usual suspects that day for our usual lunchtime run, I didn’t expect to end up looking at a coworker’s naked buns, but that’s the way things worked out in the end.  She was trotting down the Frog Pond trail twenty feet ahead of me when, all at once, she reached back and pulled down her running tights.  As I was trying to figure out what to make of that move, she suddenly accelerated away from me, flying down the trail at an inspiring pace, and reaching back with her hand and slapping at one startlingly-white cheek.  “Ow! Ow! Ow! Ow! Ow! Ow! Ow!” she said—though she repeated it more times than that.  Finally she came to a stop and turned to face me, indignantly pulling her tights back up.  “I got stung by a bee!” she said.

“It wasn’t a bee,” I said.  “It was a yellow jacket.”

Sometimes being Ranger Randy can almost get you smacked.

 

*          *          *          *

 

Well, the correction needed to be made, okay?  Too many people in this world don’t know the difference between a honey bee and a yellow jacket and it’s my job to enlighten them at all the wrong moments.   They are very different creatures.  They are both yellow and black and they both sting, but there the similarity ends.  A yellow jacket is not a bee, it’s a wasp, and by the way, you’re much more likely to get stung by one, and not just because their personality makes honey bees seem downright cuddly by comparison, but also because they don’t nest where bees do, way up in some tree cavity, conveniently out of the way.  Nope, they nest in shallow burrows right underfoot, just beneath the forest duff.  Walk too close to a nest, and one or two of them can get irate.   Step on it, and they attack in force.

BeeAndYellowJacket2
European Honey Bee (Apis mellifera)                                                 Yellow Jacket Wasp (Vespula vulgaris)
By Bob Peterson
[CC BY-SA 2.0]                                                                                  By Audrey [CC BY 2.0]

I have a relationship with yellow jackets (vespula vulgaris) that is just way more intimate than a cross-species relationship should be.  I’d estimate that I’ve been stung by those things over two hundred times, though I don’t think I have ever been stung on the butt, and the principle reason for that is that I was always wearing heavy work pants, and the principle reason for that is that, well…um…I used to be a logger.

People are surprised when I tell them that, because I’m now such an unabashed tree-hugger and militant environmentalist, but I sort of got here the long way around, and when I yell and wave my arms at the public hearings in defense of our forests, I actually know whereof I speak—the truth is that I have slain a lot of trees, and I have seen the timber industry propaganda from its back side.  I have a two-year degree in forestry, which is another word for logging, and I worked for two seasons in the woods before several things including the intellectual vacuum of small logging towns drove me on to other things.  For one summer while I was in college, I worked on a crew doing something the Forest Service calls tree thinning.  When you thin a stand of trees, you cut every small tree in about a twelve foot radius around the biggest and best looking one, to open up light and nutrients for the Chosen Ones so that they’ll shoot up and become lumber more quickly.  It’s a god-like job, deciding who lives and who dies.  You do this to an entire forest, finally leaving a bunch of perfectly-spaced trees sticking out of a five foot layer of slashed-up trunks and branches where the forest floor used to be.  And of course, you’re only supposed to spare the commercially valuable timber species.  So if, say, a tall, beautiful western black oak (Quercus kellogii) is within twelve feet of a pine seedling, you’re supposed to fell the oak.  (Black oaks are beautiful trees, and I didn’t follow directions well at times.)

In the course of all this, you step on pretty much every square foot of every acre of that forest, or if you don’t you drop a tree on it, so if there’s a yellow jacket nest anywhere, you will get mixed up with it.  And toward the fall, there are a lot of them.  Several per acre.  There are plenty of ways to get injured or killed when you spend your days surrounded by roaring chainsaws and falling trees, but this was by far the one that bedeviled us the most.

And I’ll tell you another difference between the two insects:  When a honey bee stings you, she leaves her stinger and a handful of abdominal organs imbedded in your flesh, and then quickly dies.  Yellow jackets don’t have barbed stingers, which means they can sting you repeatedly and fly away smiling and attack again tomorrow.  One time one of them danced down the side of my face, stinging me five or six times in a crescent running from my right ear all the way across my upper lip.  The little sucker got away clean, too, even though I risked life and limb by removing one hand from my chainsaw to slap at her.  Another time I walked up to a crew mate, and he was standing thirty feet away from his chainsaw just looking at it, where it was sitting there on the forest floor.  Puzzled, I looked at it with him, wondering what was up.  Then I noticed that the saw seemed to be oddly in motion.  Then I realized it was covered with yellow jackets.  He’d set it down on a nest.  He’d only gotten a couple of stings.  They were attacking the saw.  But that was going to have to change.  We contemplated the thing.

“Well…you can’t just leave it there,” I said.

“I know…” he said.  We looked at it some more.

“You gonna go get it?” I said.

“I thought you might.”

We looked at it some more.  “I already have a saw,” I said.

“Mm-hmm,” he said.

Finally he let out a rebel yell and charged in at full flight speed, snagged the saw with one gloved hand without even slowing down and disappeared whooping and hollering into the woods.  I stood looking after him.  He didn’t quiet down for some time.

They have marauding personalities.  They are inquisitive, opportunistic, tenacious and ravenous.  When they check you out they have a sinister way of feinting back and forth just above your skin, like a boxer about to throw a punch.  Even people who study wasps for a living call them “extraordinarily aggressive.”  Almost every other wasp in the world is strictly predatory and hardly ever comes into contact with us, but yellow jackets are very unusual in that they have a scavenging behavior on board, and the sense of curiosity that always accompanies that, so they mix it up with human beings all the time.  They get thick around picnic tables.  Wave one away and she’ll immediately return.  Swat her and she’ll get mad.  They’re well-respected in the woods, both by us and other insects.  Flys, moths, beetles and even other, non-stinging wasps mimic their markings protectively (it’s called Batesian mimicry), but the yellow jackets do have their own predators, including other wasps.  We once hooted and cheered like kids as we watched a yellow jacket and a bald-faced hornet (Dolichovespula maculata), which is a larger, black and white wasp, roll around on the stump that was our lunch table, locked in a predatory battle to the death.  The yellow jacket finally succumbed, and the bald-faced hornet flew away with her prize—right into a large, orb-shaped spider web twenty feet above us.  Nature in action.  A bad day for both of them.

2919baldf.w
Bald Faced Hornet (Dolichovespula maculata)
By Beatriz Moisset [GFDL]

Like bees, they have a potent venom but in a tiny quantity, and most people suffer no serious effects from a sting or three.  But if you’re allergic or  you get swarmed, you can quickly end up in anaphylaxic shock, which is a deadly condition in which your throat swells shut, among other things.  Everyone who works in the woods is asked whether they have an allergy, but of course not everyone knows whether they do or not, and besides, allergies can come and go.  There was a folk legend going around the Forest Service office I worked out of, about a foreman who was supervising a crew in the woods when a worker stepped where he shouldn’t have and picked up several stings.  The foreman asked if he was okay.  Yeah, the guy said.  The foreman asked if he was sure.  Yeah, no problem! he said.  The foreman looked at him.

Later the foreman couldn’t explain why he did this, but he grabbed the guy, heaved him into the pickup and peeled out for town.  By the time they got to the hospital he was comatose.  He’d had his life saved by a man willing to trust his instincts.

Well, that’s the story on yellow jacket wasps, but it’s not the whole story.  I wrote this article entirely from our perspective.  In the next post, I’ll tell the tale through their eyes, and I’ll take you inside a nest, and introduce you to the queen.

Stay tuned.

 

 

 
Copyright © 2013 Randy Fry

By |2017-05-24T00:03:07-05:00October 12th, 2013|Nature Essays|1 Comment
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Black Wingtips and Electric Breasts

I told Byron’s fiancé Roni, on a nice hike we went on the day after Thanksgiving, that large birds have black wingtips because black feathers are stronger.  I was pretty proud of myself—I thought this was a pretty cool factoid—but she came back with that feared and revered question, that eternal one-word query that so haunts parents and scientists alike:  Why, she said.  Why are black feathers stronger?

I considered making something up, but she’s getting where she knows me too well, so I took another dive into this subject.  Here’s what I found, and I promise not to go off on any tangents this time.

So if you were a bird of paradise and you wanted to show off for a pretty girl, how would you make your chest blink back and forth between two colors?

Okay, call it a tangent, but it’s where you’re about to end up.

First, just to demonstrate that I do have some focus, I’ll answer Roni’s question:  Black feathers are stronger because they contain the pigment melanin.  Melanin occurs in granules, and any structure containing granules is, not stronger really, but more resistant to abrasion.  It doesn’t dent or scratch as easily.  And scientists have been able to prove that for cracks to propagate in the keratin of a bird feather, there first has to be damage to its hard surface.  Without the initial surface damage, you don’t get cracks developing into what the FAA calls “catastrophic structural failure.”  You find it in high-performing flyers like hawks and gulls, out toward the wingtips where the stresses of flight are the worst, but you also find it on small birds in desert areas, because they contend with a lot of abrasion from blowing sand.  Unkind scientists spent some time denting the beaks of starlings (yeah, I know…), which are also made of keratin (so are fingernails, hooves and the baleen of whales), and they found that beaks with lots of melanin resist damage 39% better than those without, which means that you can be a large bird without black wingtips (the great egret comes to mind), but your flight feathers will have to be about 39% beefier to put up with the abuse.

GreatEgret
Great Egret (Ardea alba)
By Ardea_alba_-San_Francisco_Bay,_California,_USA_-flying-8.jpg: Don DeBold derivative work: Snowmanradio
[CC BY 2.0], via Wikimedia Commons

Feathers are the most complex external structure found on any vertebrate.  They are amazing pieces of evolutionary engineering, but what blew me away about them on this read is what goes on microscopically on their surfaces, creating their structural colors.  As I talked about in the last article, birds have two ways of achieving color:  pigment, and iridescence, but actually it’s not always iridescence, which is rainbowing, so scientists just call it structural color.  The easiest kind of structural color to describe is an oil slick on water.  You end up with two reflective surfaces separated by a teensy distance.  Half the light reflects off  the first surface, and the other half reflects off the second.  The two waveforms return to your eye together but they’ve traveled different distances and they’re out of sync, and they interact, interfere, reinforce, and generally have a good time all over the spectrum, creating new colors depending on the viewer’s angle.  That’s iridescence.  Scientists know how to overfly an oil spill and measure the film’s thickness by studying its color.

Thin_film_interference
Thin-film Iridescence
By Chanli44 at English Wikipedia [Public domain], via Wikimedia Commons

Birds, though, have taken all this to a whole new level.  They have total control over what colors get created when, and from what angle, and I mean, it’s sophisticated.  They use, just to toss out a few terms that ornithologists think in, reflective films, diffraction gratings, selective mirrors, photonic crystals, crystal fibers and deformed matrices.  They are highly precision structures, and when I call them microscopic, I mean really small, like, as small or smaller than the wavelength of light they work with (which renders ordinary light microscopes useless for studying them).  And the color doesn’t always look reflective.  The deep, rich green of many parrots is created by selective mirrors, which are micron-sized bowls which, because of their size and shape, are able to reflect exactly two wavelengths of light—yellow is able to reflect straight off the bottom of the tiny bowl, and blue is able to do a two-step and ricochet from one wall to the other and then back out.  Nothing else reflects.  The result is a perfect green, but it gets better:  The angles of the bowls are carefully randomized so that you see the color from any angle, and you’d swear you’re looking at a pigment.  But you’re not.  Grind the feather up in a mortar and pestle and you’ll have a gray powder.  Many species do use the rainbowing of iridescence but, again, angle the mechanisms carefully in all directions so that it works from any angle and there is a single vibrant iridescent color that hardly varies with viewpoint.  Beetles do this.  The colors of the blue and yellow macaw (Ara ararauna) are structural, and though very striking, they do not come and go, because the structures (deformed matrices, in their case) are oriented in all directions.

BlueAndYellowMacaw
Blue and Yellow Macaw (Ara ararauna) — No pigment in those colors!
By Luc Viatour [GFDL] [CC BY 2.0] [CC BY-SA 3.0], via Wikimedia Commons

Birds mix and match the tricks of color.  They arrange these structures in concert to create combinations of effects, and they mix pigment color with structural color.  The green parakeets in pet shops are a combination of a yellow pigment and a structural blue.  An albino parakeet is blue and white.  In olive-colored songbirds like vireos you’re seeing a structural yellow, plus melanin.

When they do decide to use the angle of view to get an effect, it can be pretty stunning.  It’s why the throats of the hummingbirds in your yard flash as they slalom through the air.  Western bluebirds look drab from most perspectives but now and then they’ll catch the sunlight right and break your heart.  But my favorite is the bird of paradise called Lawes’s parotia (Parotia lawesii), whose breast plate has structural thin-film iridescence, but arranged into V-shaped ridges, so that it reflects only two colors from only two directions, electric blue-green from one direction, and electric yellow-orange from the other.  When he dances for his girl, he shifts his breast back and forth and it blinks from one color to the other.

Pretty amazing stuff, but then birds have had forty million years to work this out, which is about 39.8 million years longer than we’ve existed as a species.

AlbinoParakeet3
Albino parakeet (left)
By Iaminfo [CC BY-SA 3.0] [GFDL], via Wikimedia Commons

And to add one more wrinkle to this, birds can see in the ultra-violet spectrum.  They have a fourth cone in their retinas that we don’t have.  A scarlet ibis isn’t scarlet if you’re an ibis.  He’s deep purple, reflecting a strong structural ultra-violet that we can’t see.  Many species of birds appear to us as if the males and females have identical plumage, but they don’t.  Not to each other.  The western bluebirds I mentioned would be much more stunning birds if we could see in UV.  Scientists actually figured this out years ago because the hawks weren’t stopping in a forest in Bavaria.  Bear with me.  They would always stop over on their migration to hunt voles, and people noticed that when the voles were having a bad year, the hawks wouldn’t even stop.  Wouldn’t even drop down and give it a try.  They’d just pass on over.  How did they know?  It turns out that vole pee reflects ultra-violet light.  To the eyes of a hawk, those little vole trails light up the forest floor like strings of fairy lights.

Now you know.

 

 

 
Copyright © 2012 Randy Fry

By |2017-05-24T00:03:07-05:00December 1st, 2012|Nature Essays|1 Comment
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Pink Flamingos and Snowball Earth

Happy Thanksgiving, everyone, and to all my Indian friends, happy Diwali!  This year’s Ranger Randy research assignment from the Thanksgiving gathering of family and friends involved flamingos, and the Zen question of why pink flamingos are pink. A scientist at the Monterey Bay Aquarium once told me that if you grind up a blue jay feather in a mortar and pestle, you get a neutral gray powder, and I’ve always promised myself that someday I’d do that and see if it’s true, just to keep the scientific community honest.  There’s no pigment behind many of the colors you see in bird feathers.  The colors, especially the vibrant colors in something like the red throat of a hummingbird, are accomplished through refraction, like the rainbowing on an oil slick.  This is an extremely clever evolutionary trick, because refraction only works in direct sunlight, which means that if you’re a bird who needs to both show off and worry about predators, you can fly up into the sunlight and make a great, showy spectacle of yourself, but as soon as you drop into the shade of a bush you blink out like a light.

What’s unusual about pink flamingos is that they do have pigment in their feathers.  It comes from the brine shrimp they eat.  Actually, it comes from the blue-green algae that the brine shrimp eat, which contain carotenoids, an organic pigment which gives carrots and apricots their color, and also underlies a ton of biological processes including photosynthesis.  The flamingos who eat more blue-green algae directly are a deeper pink than those who get the carotenoids only through the shrimp.  The babies are born gray, and even an adult flamingo who does not eat the shrimp or algae will gradually turn almost completely white with only a faint pinkish blush.  In zoos, they have to put pigments in their food, to keep the visitors from being extremely disappointed.

Carotenoids are also the reason that fall leaves turn the wonderful red and orange colors they do.  The other pigments like chlorophyll fade first as winter approaches, leaving the carotenoids.

But here’s what really took me off on a tangent on this one.  And what the hey, tangents are what I do in these articles, and that’s as it should be when you’re writing about nature.  John Muir put it well: “Tug on any one thing in nature and you find it connected to everything else.” So here we go: If I understand this correctly, blue-green algae is not exactly an algae, it’s a photosynthesizing bacteria, and here’s the tangent:  it’s the reason we have our atmosphere.  I’m not making this up.  These ancient little one-celled creatures are the reason we can breathe, and the reason our skies are blue.  When their numbers in the oceans started to boom, it was 2.4 billion years ago, and there was no oxygen in our atmosphere at the time.   But photosynthesis generates oxygen (which is why we will all die when we finally manage to kill all our forests), and at first the oxygen molecules they generated just combined with iron molecules in the water and sank like little molecular pebbles to the ocean floor and were never heard from again, except that they created a layer of reddish strata on the ocean floors that is still there today and provides a chronological benchmark for every geologist in the world.  This went on for two hundred million years.

Then, finally, 2.4 billion years ago, the seas ran out of iron.  It had all been swept up and sent to the bottom, and there was no more, and oxygen started to rise into the atmosphere.

What happened next is sometimes called the Great Oxygenation Event—and  sometimes the Great Oxygen Catastrophe.  To all of us, it sounds like a wonderful and blessed event, but it sort of depends on your viewpoint.  Just about every anaerobic organism on Planet Earth perished as this cloud of toxic oxygen swept over the landscape killing everything in its path.  It was one of the biggest extinction events in the history of our world, and it dramatically changed the trajectory of the evolution of life on this rock of ours.  And the mayhem and tragedy that it caused did not end there!  It also oxidized the methane in our upper atmosphere, with the result that it was no longer a greenhouse gas, and the planet was plunged into one of the most dramatic ice ages in our history, sometimes called Snowball Earth, in which some think that even the equatorial waters froze over.  There’s still argument about Snowball Earth, though.  Some argue that such a condition would not have had an exit door—that is, it couldn’t have happened because it couldn’t have un-happened.  With that much reflectivity on the surface of the earth, our planet could never have warmed again.

But smile—we don’t have to worry about Snowball Earth.  Nope, the opposite fate is staring us in the face.

And on that cheery note, I’ll leave you to enjoy your leftover Thanksgiving turkey and Diwali sweets.

Now you know.

 

 

 
Copyright © 2012 Randy Fry
By |2017-11-12T11:31:17-06:00November 25th, 2012|Nature Essays|2 Comments
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Hurricanes and Flying Palapas

When Hurricane Wilma hit Dave and Nancy’s Yucatan house in 2005, it hit it so squarely that afterwards all the phone poles north of town were on the ground pointing west, and all the phone poles south of town were on the ground pointing east.  Dave picked us up at the airport and driving back you could look right through the jungle—not a leaf anywhere.  It had been completely defoliated.  One billboard after another was flat on the ground, and Dave had been wandering the neighborhood looking for the palapa that had been on his rooftop terrace.  Palapas are thatched structures used for shade in the Yucatan.  They’re made of logs.

palapa
Palapa
By Thelmadatter
[CC BY-SA 3.0], via Wikimedia Commons

We all know what a hurricane can do to a city, but a friend of ours who regularly visits Dave and Nancy with us asked me recently what hurricanes do to ecosystems.  It was an interesting question that I had never asked myself.  What is the natural effect, and the natural response, to an insanely violent event like a hurricane?  If we remove human beings from the picture for a moment—our cities, our hotels, all our other misdeeds and miscalculations—then what goes on in coastal ecosystems during a hurricane?  Chatting with Susan about the question that night over cocktails, I made a prediction:  I predicted that when I looked into this I would find that the organisms in tropical coastal ecosystems not only can handle hurricanes, but need them.  It wasn’t the most brilliant or daring prediction, but anyway it looks like I was right.

A hurricane is not only a violent event, it is a chaotic one, and when I say that, I’m not using hyperbole, I’m using mathematics.  Chaos mathematics was invented by a guy named Edward Lorenz, and he was a meteorologist—he was trying to write a computer program to model world weather patterns.  Hurricanes in particular and weather systems in general are so complex that predictability itself is defeated, and chaos theory is what Lorenz developed in order to analyze the stuff.  Inherent in chaos theory is what Lorenz called the “butterfly effect,” the idea that a tiny change in initial conditions, like the flap of a butterfly wing, can have a huge effect down the line—like a hurricane.

Which is one reason no two hurricanes are the same.  You might experience anything from lashing winds to rising sea levels to the breaching of barrier islands and sudden exposure to the open ocean, or it may just park above you and dump torrential rain for several days.   A large hurricane can have a storm surge at its center where the sea level is thirty or forty feet higher than normal, and that’s in deep water—before it hits the coast and the ocean floor runs up under it and everything stands up into breaking waves.  It can redraw coastlines by 100 meters or more.  Katrina and Rita alone sent over seventy square miles of our fair land into the deep blue sea, but hurricanes also deposit huge amounts of sediment and nutrients and raise the soil level in coastal marshes and keep them from subsiding and becoming open water.  Estuarine channels and waterways may protect the coast against the storm surge, and you may feel fortunate to live at the end of one, but they can also focus and funnel the surge, depending on their shape, with the result that, hours after the battering, when you’re looking at clear skies and  thinking you’ve survived it, a wall of water suddenly flattens you and everything around you.  The National Hurricane Center used to offer up storm surge measurements along with its one-through-five Saffir-Simpson category rating, but they finally threw up their hands and gave up on it.  The whole thing was just too localized, and their credibility was going to hell.  What happens to you in a hurricane depends on where you are, what you’re up to, and how the gods of chaos mathematics are feeling that day.  Only one thing’s for certain:  it will change your life.  Right underfoot, or paw, or flipper, things will change.  Your world will be different in the morning.

And nature just loves that.  It loves it to death.  I’ve said this in more than one article:  the balance of nature may be a balance, but it’s not a stasis.  Things out there are constantly in motion, and organisms have evolved accordingly.  The idea of a permanent community that never goes anywhere and would be devastating to lose, is a peculiarly human notion.  What the natural world is full of is opportunists, and change is their medium, chaos is their opportunity generator.  Mind you, they don’t have to like it, and any one organism in a hurricane may live or may die, but according to my reading, the communities tend to do just fine in the long term, and in fact need what the hurricanes bring them.

DSC00338
Mangrove forest in the Yucatan. The red water is from the tannin of the mangrove trees.
Photo by Susan Fry

Mangrove forests are a delightfully unlikely plant community.  They occur all over the tropics in shallow coastal waters and fine, depository soils, but the word “mangrove” actually doesn’t have a taxonomical meaning.  These trees and shrubs are all a case of convergent evolution—innovative desperados from a wide variety of family backgrounds who have all figured out a way to live with their roots submerged in saltwater,  which is really a pretty impressive trick when you think about it.  Heck, most trees will suffocate if you submerge their roots even in fresh water.  Roots simply have to have free oxygen, it’s that simple, and also, salt levels that high are in opposition to every osmotic process in their bodies.  Mangrove species each employ a different array of tricks, but they all pull it off—they send things called pneumatophores up into the air like little breathing straws, or they get oxygen through special organs in their bark called lenticels and send it down from there; they have subcellular mechanisms in their roots that admit water but exclude salt, or they dump the salt they ingest into their older leaves and then drop them in the drink like little garbage bags.  They stand absurdly on spindly, stilt-like roots, and the dense network of roots slows tidal actions and causes the deposition of the fine silt they need, creating their own soil exactly the way they like it.  Red mangroves (Rhizophora spp.) produce seedpods that look a lot like large string beans, but what’s different about them is that the seeds germinate right inside the pod before it drops into the salt water and floats away.  After it has drifted awhile, it redistributes its weight and goes from floating horizontally to vertically, so that its bottom end nudges up against the silt and it can establish itself.  And this is even cuter:  if it fails to establish itself, it will redistribute its weight again and float away horizontally to try somewhere else.  Mangrove ecosystems are just bizarre—if you were a working god in a design room somewhere with the other working gods and you proposed a mangrove forest, you would be laughed out of the place.  Yet they cover three quarters of tropical coastlines, and the habitat is rich, home to all manner of crustaceans and mollusks and sessile (attached) organisms, and a tremendously important nursery for small fishes.   And they do protect the coastline from the worst ravages of the hurricane, but not from all of it, and also, they themselves are changed by it, and they adapt.  After the storm there may be several inches added to the underwater soil among all those stilt roots, and they immediately start sending out rootlets horizontally in the new layer, stabilizing it and soaking up the windfall of new nutrients.

Forests may get completely defoliated by the wind, but the only knock-downs are usually at the edges.  (As human development fragments the forests, there is much more of this edge habitat, and much more damage.)  After the storm an entire forest’s worth of leaves starts decaying in the inland bodies of water, depleting oxygen and causing huge fish kills.  Arboreal lizards are suddenly completely exposed to airborne predators in the leafless forest, and may try to drop down to the lower branches for protection, but will be competing there with better-adapted creatures designed for the job.

Migratory birds cross the Gulf of Mexico toward the end of hurricane season, and if a hurricane is threatening, they’re smart enough to wait for better weather before taking off.  They have enough fat to power the 600-plus-mile crossing, but only in reasonable conditions, and in the end they’re as imperfect as we are at predicting the weather, and they can get caught out.  Bird migrations are not as hard-wired as people think, though, and if they land in their usual location and the place has been stripped of all fruit, leaves and insects, they’ll continue on, looking for better stuff.  If they get blown hundreds of miles off-course, they will look around for a stopover that works, and regroup.  (Human developments are making these stopover habitats harder to find for exhausted birds.)   Thousands of birds can perish in a hurricane, or starve in its aftermath if they don’t know how to deal with something like a leafless forest.  Cavity nesters get hit particularly hard following a hurricane, because trees with cavities are by nature weak or already dead, and go down in the wind a lot, often snapping right at the cavity.  When Hugo hit the Carolinas in 1989, one forest lost 87% of its nesting trees and 67% of its red-cockaded woodpeckers (Picoides borealis).  The bird populations can rebound in four or five years if they’re otherwise healthy, but of course it’s the species that are already in trouble that get hammered.  The Puerto Rican parrot (Amazona vittata ) got its numbers halved by Hurricane Hugo in 1989—from 47 birds down to 23.  But even as all these creatures are enduring huge death tolls, they are also taking advantage of the shifting patchwork of habitats.  Edge habitats and transitional habitats are rich places.  Opportunity abounds.

USGS_HurricaneCharleyBreachCaptivaIsland
North Captiva Island, before and after Hurricane Charley
By United States Geological Survey [Public domain], via Wikimedia Commons

Barrier islands are skinny spits of sand running parallel to coastlines, and they are created by—and reshaped by, and destroyed by—natural oceanographic forces, mostly wave dynamics.  Scientists have been proposing theories about their formation since 1845, but to this day you could walk into any oceanography symposium and assert any theory, and you’d more than likely end the evening with a black eye.  The islands  may have vegetation on them, even groves of trees, but make no mistake, at the end of the day they are sand spits, and they are quite fragile.  There’s a whole rank of them along the U.S. Gulf Coast, and in the shallow sounds between them and the mainland are great beds of sea grass, rich incubators and nurseries, full to bursting with shrimp and other crustaceans, young bony fishes and turtles.  Hurricanes overtop the islands and open up new channels through them, suddenly exposing the mainland to direct waves from the storm.  Whole sand dunes get washed into the sound and bury the sea grass beds, but the beds recover quickly, and even the channels blown through the islands heal themselves in following years.  Hurricane Charley, in 2004, opened a new channel fully a quarter mile wide through North Captiva Island, a barrier island off  Florida (fully developed and inhabited, of course).  By 2010 the gap had closed again through natural processes.

Coral reefs are notoriously fragile, but really only because they live in a human-infested world.  They don’t actually mind hurricanes that much, and branching coral like staghorn coral (Acropora cervicornis) even relies on strong storms to distribute itself.  It does reproduce sexually once a year through broadcast spawning (that’s the practice of throwing sperm and eggs into the water and hoping for the best), but its dominant mode of reproduction is through fragmenting.  Storms break off branches and sweep them away, and they are able to reattach to the substrate and start new colonies.  It’s classic opportunism:  after a hurricane staghorn coral leaps to life and recolonizes explosively, turning the most destructive storms on the planet to their advantage—but there’s a problem with it, too.  The problem is that it is asexual reproduction, and doesn’t generate a lot of genetic diversity, and staghorn coral consequently hasn’t handled a changing world very well.  Disease and changes in temperature or salinity give it real trouble, and staghorn coral is currently classified as critically endangered.

Well, to wrap up the story of the first organisms mentioned in this yarn, Dave and Nancy are both okay.  They’ve evolved their own survival mechanisms, and one of them is a sense of humor.  The two of them actually survive about one of these things per year on average, and they’ve gotten pretty good at it.  Once they had just received and installed thousands of dollars worth of new windows when they found themselves in the sights of a hurricane.  Dave raced through the house uninstalling them all again, so the storm could blow through the structure.  It worked.

It’s all about handling change.

Now you know.

 

 

 
Copyright © 2012 Randy Fry

By |2017-05-24T00:03:07-05:00September 17th, 2012|Nature Essays|2 Comments
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The Wisdom of the Hive

When a column of marching army ants in Africa attacks a termite mound, remarkable things happen.  The termite queen, who is a helpless, blob-like egg-laying machine, is rolled and pulled into a special chamber by her tenders and walled in.  Soldier termites swarm out of the nest to engage the enemy, and worker termites seal off the entrances behind them.  They will not be able to return.  Win or lose, every one of them will die.  They fight fearlessly, unquestioning, protecting a civilization they have built that might include wells that go down to the water table, ventilation shafts, galleries, fungus gardens and a royal chamber for the queen.  The termite soldiers are several times bigger than the ants, with huge mandibles, but the ants swarm, and attack the extremities, grabbing the hind legs and the antennae, and holding them down for the hoard to kill.

The march of the army ants is a scorched-earth rampage.  Scouts out ahead of the column paint any prey animal they find with a pheromone that triggers attack by the rest of the swarm.  They kill and eat mostly other small invertebrates but can bring down bigger animals including rodents and even human beings.  When they attack a termite colony their goal is to kill the queen so they can abscond with all the eggs.  They cross watercourses and gaps in the landscape by creating swinging bridges with their interlinked bodies, which Susan and I have witnessed in the Yucatan Peninsula in Mexico.  When the army rests, they create “bivouacs” with their bodies, sheltering the queen.

And what’s remarkable about all this?  It’s that any one of these creatures only has a neural junction box for a brain.  Each individual only follows a small set of rules and cues.  Where does the intelligence come from?  Is it even intelligence?  Do we need to redefine the term?

In the scientific community the phenomenon goes by several names:  collective intelligence, emergence, agent-based models, stigmergy.  Each “agent” leaves a trace of its action in the environment, and that triggers a further action by another agent, and what emerges is a whole that is greater—more complex and more intelligent—than the sum of its parts.

Ants
Leaf cutter ants in the Yucatan
Photo by Susan Fry

The leafcutter ants in Central America (Acromyrmex and Atta spp) are thought to be the most complex societies on earth next to humankind.  Susan and I shot this photo of them in the Yucatan.  The columns march for hundreds of yards, threading through all the trees in the forest.  Susan was asking a good question:  Look around you, she said—there are trees everywhere!  Why are they marching all over the place for their leaves?

What leafcutter ants do with those leaves is grow fungus gardens.  The fungus they grow is in the Lepiotaceae family, and it’s a complete, two-way symbiosis—neither ant nor fungus can survive without the other.  If there’s a leaf in the mix that messes up the fungus growth, they detect it and stop gathering it, and they range far afield to collect just the right mix of leaves.  The plants, in turn, detect the attack and start producing “volatile organic chemicals” which are among other things fungicidal, and the ants are selective as they forage and avoid these leaves.  Their fungus gardens include a “nursery” where they experiment with different mixes of leaves, and when they find a leaf that grows the fungus well, from a tree which has not yet mustered its chemical defenses, they remember exactly which tree those leaves came from, and columns of ants seize the moment and maraud that way, stripping it of all the leaves they can before it wises up.

But their astonishing “intelligence” does not stop there.  A mold called Escovopsis is constantly threatening their crop, and the ants have a bacteria growing on their exoskeletons called Actinobacteria which secretes an antibiotic which fights it.  I’m not making this up—these ants invented antibiotics twelve million years ago.  Not only that, but throughout that time, they have somehow prevented Escovopsis from becoming resistant to the antibiotic, a feat medical science has not been able to pull off yet.

Their nest mounds can be 100 feet across and extend 18 feet into the ground, and the colonies can contain eight million individuals, so as with any urbanized civilization, waste management is a problem.   They maintain a garbage heap, constantly working and shuffling it to keep it decomposing (this is done by the older, less useful worker ants—the young ones in their prime are indoors, at work in the fungus gardens).  They place the heap above ground at a location which is equidistant from all hive entrances, to prevent contamination, and that constitutes solving a geometric problem.  They can find the shortest route to a source of leaves, which constitutes solving a geographic problem.  And they routinely shore up walls and colony entrances so that they don’t collapse, which constitutes solving an engineering problem.

            It’s not just naturalists who study this stuff.  Computer scientists and industrial engineers look at it:  How can you create a complex system with a simple set of instructions?  Experts in crowd handling look at ant behavior, and so do traffic flow experts.  Two-way traffic lanes can be observed in ant trails, and people who have to devise the crowd handling at concerts so that stampedes are prevented, study the ants.  A systems analyst at Southwest Airlines named Douglas Lawson modeled ant behavior to figure out how most efficiently to get people onto an airplane.  He knew that ants are the experts at doing complex things by following simple instructions.  (The answer:  Open seating.  It’s why Southwest uses it.)  Research by humankind’s brightest minds is going on every day, but the ants, it seems, have it figured out.  And they have figured it out without anything you could call a brain.

What is intelligence, anyway?

Just looking at my own species—and my own life—I have to say that I feel a connection to these societies of insects.  The wisdom of the hive is, I think, very real for us as well.  I have spent a fair amount of my life looking for wise men and gurus, and I have decided that there are none.  The wisdom, I think, lives in the spaces between us.  It is not individual, it is synergistic.  It is the back side of our human tapestry, binding us together in ways that we do not see.

I am just dying to know:  What is the big problem we are solving, which our brains are not even capable of understanding?

By |2017-05-24T00:03:08-05:00June 30th, 2012|Nature Essays|5 Comments
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