Friday, August 28, 2009

Things That Go "Blink" in the Night

As a kid growing up in Southern California, I was captivated by the idea of "lightning bugs". They seemed about as real to me as

dragons or unicorns. Whenever these fanciful fireflies ever came up during class in grade school, there was always some lucky kid who'd actually seen them, like on a family vacation or something. I was so envious! I even recall a teacher who'd grown up among them, regaling us with tales of their niftyness. And those children's stories of collecting fireflies in a jar and using them to light the way home―like how cool is that!


Imagine my delight at witnessing a winged flash in the flesh for the very first time. By then I was university educated and wise to the ways of bioluminescence. Yet I experienced the moment with my giddy inner child―a unicorn come to life! On passing more and more time in humid tropical climes, I've come to appreciate the diversity and ubiquity of "lighting bugs"―yet they never cease to thrill me!


There's one here on the Osa that glimmers with a faint luminous green gleam, then suddenly fires up to a glowing hot orange as it takes to wing, as though igniting a second stage booster rocket. Then there are those big ones with the pair of headlamp beacons that actually illuminate leaves, branches, walls, and ceilings as they fly by, like the landing lights on a 747. I still vividly recall walking down a dirt road one night on Nicaragua's Pacific coast.

There had been a hatch of fireflies; thousands of twinkling pinpricks of light. With the incessant blinking and constantly shifting visual frame of my walking pace, it was like watching a collage of images from the Hubble Telescope deep space view―far better than any laser light show from my rock 'n roll youth.


Last night I got up to pee and saw a lightning bug on the wing, its green navigation lamp bright enough to illuminate the floor of my open-air bedroom. It flew along, a slow pulsing glow, gradually homing in on the steady green blink - blink - blink of the solar charge controller at the opposite end of the room. My firefly

converged on the rhythmic LED, seemingly intent on fulfilling a timeless ritual, and then went dark, as if embarrassed to have been tricked by a winking mechanical counterfeit.


As I awakened early the next morning, my mind replayed the blinking ballet between my mythical firefly and the cold white metal circuit board box. I recall thinking at the time that I must get my flashlight and check this out, then remembered that my light was downstairs, so I just laid back to resume my slumbers. But as I roused myself in the dim light of dawn, I started to wonder; had I really witnessed a false mating play between insect and LED? Or had I imagined it all in a sleepy waking dream state?

Night Blooming Jasmine Just Floors Me!

Night blooming jasmine (Cestrum nocturnum) just floors me. I caught a whiff of its intense perfume and immediately rose to my feet, sniffing and orienting myself to the heady scent. It seemed a dense cloud, wafting around the deck and into the kitchen, not diffusing as you might expect, but hanging tight as though somehow the fragrance compounds cohered to one another.


My response was involuntary and deeply stirring. Made me sympathetic to the moths who pollinate these intensely fragrant flowers. Sweet obsession. Yum! (Native to Asia, with unfortunate invasive tendencies in some areas, though seems well-behaved around here.)

Thursday, August 27, 2009

Cidada!

The other morning as I sat down to my desk, I noticed a cicada dead on its back. I picked it up to flick it out, when I felt his legs stir and cling feebly to my thumb, steadying himself like some beer-soaked frat boy slowly rousing himself and wondering whether he'd had a good time last night. I retrieved my camera with my free hand and clicked (below). Then, without warning, he just went off: "whhhrrrRRRLLLclclclCLCLCL!"
Listening to a chorus of cicadas, you'd assume you're hearing a host of hundreds or thousands. But holding this little dynamo in my fingers, I sensed the power of one. A mere quartet of these little virtuosos could produce a mighty sound. And when their numbers really swell, the racket can be deafening! A locally seasonal species known as the Dawn and Dusk Cicada, whose sentinel call bookends the day, has a much deeper more resonant twang; as though channeling an "Ommmm" from a faraway Tibetan monastery through a Jimi Hendrix fuzzbox.

Remember those little metal cricket clicker toys, with the strip of spring steel that you pushed "click" and released "clack"? Clickclackclickclackclickclack... Drove my mother crazy! Cicadas are about the same size. If those cheap little made-in-Japan noise toys of my childhood had evolved along with Japan's consumer products technology revolution, they would probably resemble the metal-flake sea-green gossamer-winged fellow I held in my fingertips (the modern version being fully automated, lithium ion-powered, and GPS-equipped; with downloadable "whhhrrrrRRRclclCLCL" tones on the website).

Like so many other insects, cicadas are drawn to light at night. They're big enough to make quite an impression when they come hurtling in, as you sit quietly dining by candlelight. They may be reckless but they're hardly malicious; just clumsy and easily disoriented. Landing on the table and sitting perfectly still, they'll hesitatingly start to crawl toward the object of their obsessioncandle glowand suddenly launch themselves full force into the candle vase (Slam!) then lay languishing on their backs, stunned unconscious, before stirring and having another go (Slam!).

I was cleaning up after dinner when something big landed on my nose
I was helpless, both hands in dishwater. With a cross-eyed downward glance, I detected out-of-focus metallic blue-green, dislodged the little bugger with a shake of my head and upward puff. What is it with these guys, anyway?!

Monday, August 17, 2009

Year of the Locust

For some reason, there have been a lot of grasshoppers around this year. Big ones. From a distance they look like birds or bats in flight, only giving themselves away by the clumsy way they land. At peak density a couple months ago, it seemed there was always one or two in flight wherever you looked. And when a troop of monkeys passed through the canopy, a dozen or more grasshoppers would take to wing at once (being a tasty treat among Spider Monkeys and White Face Capuchins). On one occasion, I watched as spider monkeys moving through the mango tree let loose a volley of grasshoppers, one of which was picked off on the wing by an enterprising Roadside Hawk who'd been lurking in the shadows.

Ever wonder at the difference between locusts and grasshoppers? I did, so I asked (Ask.com). Turns out, not much. Physically, you can't tell them apart. Locusts are known for having a swarming phase, usually distinct morphologically. Many locusts are now known to be just the swarming phase of a previously presumed different species. And some grasshopper species sometime engage in gregarious (swarming) behavior.


So far, no swarming. Lucky me.

The Eyes Have It

While a single candle provides only a feeble flame, an array of a half dozen provides plenty of light for dining. Plus, candles conserve battery power and aren't nearly as attractive to annoying insects as electric lights. We were about to sit down to a candlelight dinner when I saw that one of the candles had gone out. Going to re-light it, I noticed a large leaf sitting on the sand bottom of my improvised candle holder, so I reached in to pluck it out.


It turned out to be a large moth that had flown in (now my prime suspect as flame snuffer) and had probably exhausted itself trying to escape. This enabled me to handle it easily while Diane snapped a couple photos. The large false eyespots are normally hidden under the upper wings, and in it's resting pose the moth is well camouflaged (leading me to think it a leaf). But if disturbed by a predator, it need only spread its wings to reveal a pair of large menacing eyes, startling any would-be predator into believing that it may be about to become prey to a much larger beast, causing it to flee.


According to my trusty Mariposas de Costa Rica, my startling specimen was probably Automeris metzli, in the Saturniidae family. False eyespots are not all that uncommon in moths, especially among the Saturnids; although eyespots as large and distinctive as these are truly extraordinary. Interestingly, no sign of the deep dark spot is visible on the underside of the wing. And the upper wing, camouflaged to appear like a leaf when folded, has an eyespot on its underside (though not nearly as spectacular as the lower wing eyespot depicted in the photo).


And now, back to dining by candlelight...

Saturday, August 1, 2009

Arachnid Peek-a-boo

Charismatic megafauna get all the attention. You know, panda bears and their ilk; cuddly with big brown eyes and human-like traits. They're the poster children of wildlife conservation. Here on the Osa, monkeys and such fill the bill. Or macaws; big and colorful, squabbling raucously like a quarrelsome old couple, they even form life-long pair bonds. Biologists have a word for critters that embody a collection of human-endearing characteristics: fubsy.


Spiders are not fubsy. But they are no less interesting for the lack. They inspire phobic fits in many, which is understandable since most are venomous, some spectacularly so. But they are best known for their unique method of hunting: the web with which they ensnare their prey (later to deliver the coup de grace--a toxic bite).


The Golden Orb Weaver (so called because of the color of its spider silk) is big, up to 3 inches across or more, and beautiful, with jewel-like dots and patterns. They're also prodigious web builders, capable of throwing up an astonishing amount of spider silk, literally overnight. Which is why you want to keep a weather eye out for webs on morning jungle jaunts.


When hiking the trail early one morning, I immediately knew I'd walked into a web. Stop, back up, and kind of corkscrew yourself away from anchoring vegetation, raising your arms and shaking your hands to lift the threads and shake them off. Clear of the hazard, I continued on my way, quickly forgetting the incident.


Imagine my astonishment when, 15 minutes later, the owner of the forgotten web decided to rappel off the bill of my cap and position himself an inch in front of my right eye. Yikes!