Wednesday, February 22, 2012

Free-wheelin' Barnacles

There's a great lesson to be learned at Crystal River--turn off the tunnel vision. Unlike most rivers we paddle on our tours, Crystal River has a single, all-star attraction that is responsible for most of the winter visitation. There's no getting around it, people love manatees; rightfully so. However, by keeping their hot focus on this one species, many visitors leave without ever realizing they’ve just spent the day in a wonderland of amazing history, geology and archaeology. Nor have they learned about the menagerie of fascinating species that flew and swam past and, in the case of manatee barnacles, stood on their heads and waved.

If it’s ever discovered that barnacles have language, I suspect the first words we’ll hear will be, “woo hoo!!” and they will be squealed by a “manatee barnacle,” one of that special brotherhood of barnacles that arrive in Crystal River every autumn clinging to the backs of returning manatees. These are not a unique species, just ordinary barnacles in extraordinary circumstances. They are the lucky few whom fate delivered onto the back of a resting manatee at the most critical moment of their life.

Barnacles enter the world as one-eyed, six-legged, spiny-tailed, larvae called nauplius. Life for nauplius is that of care-free and unattached plankton, a not-so-exclusive category of aquatic organisms whose only defining trait is that they have little control of their own movements. Their lives are led at the pleasure of the ocean’s currents; they go with the flow, sipping fine brine and feasting on the endless supply of even smaller plankton. Theirs is the implied promise of all plankton—a life of freedom. It’s right there in the name, plankton, which comes from a Greek word for “wanderer.”

But, even the best laid plans of barnacles go often askew. A half year into its life’s journey, things begin to change for the carefree nauplii. Joints stiffen and it begins to morph into a creature that looks surprisingly like a tiny mollusk (surprising, because barnacles are not mollusks, they are crustaceans). In this new “cyprid” stage of life, the would-be barnacle foregoes feeding as it noses around looking for a suitable place to call home. It’s not choosey; oyster shells, clams, driftwood, human garbage, any solid object with enough space to do a head-stand will do. Once a place is found, the cyprid rolls over and cements its head to the surface with a dollop of brown goo exuded from its neck. This glue is powerful stuff. Dentists study it with a mind toward attaching dentures to the more storied regions of their patient’s smiles. In a strange twist, this glue which nature concocted to bind barnacles permanently in place is used by humans for added freedom—freedom to gnaw an ear of corn, freedom to smirk at less clever creatures. Having secured a home site, the barnacle encases itself in hard, calcareous shell plates. The “wanderer” has become the ultimate home-body. The only thing missing is a family.

Success, as barnacles calculate it, consists of just two things; finding a good home-site where the plankton flows like wine, and at least one barnacle neighbor with whom it can occasionally have sex. But, there’s a problem—they’re barnacles. As you can imagine, being glued to the floor by their head and being encased in a hard shell presents a challenge to the horn-fraught barnacle. But, as their half-billion year ancestry would imply, they have worked this problem out admirably.

As with many immobile sea creatures, barnacles are hermaphrodites. Each individual has both ovaries and a penis (the latter deserving honorable mention as being proportionally largest in the animal kingdom—nearly 10 times the animal’s body length). Generally speaking, barnacles spend most of their time in male mode, eating, resting and occasionally probing around with their penis for a receptive neighbor. But, once in a while, they are surprised to find themselves on the receiving end of a neighbor’s penis. Voila, they are a female—and pregnant. (this is where we might hear the second utterance—shriek?—heard from a barnacle).

For most barnacles, life is fairly predictable. But for some, opportunity knocks when they are in the critical final moments of their cyprid stage. For them, good timing, favorable currents and dumb luck come together perfectly to deliver them onto the back of a mobile sea creature such as a sea turtle, a whale or a resting manatee. It’s a life-defining moment. For the first time in its life, and probably the last, it owns its fate. In this singular instant, the soon-to-be barnacle will make the only consequential decision of its life. It has two simple choices, hesitate or roll over and attach that head…and be quick about it! One gust of water current; one shutter of the whale’s skin; one sudden notion in the mind of a manatee to move to a nearby clump of eelgrass, and all hope for becoming a true “wanderer” is gone. For the lucky few that hit their mark, it’s off to the adventurous life of a manatee barnacle.

Manatee barnacles must surely be the outlaw bikers of barnacle society when they glide into Crystal River in the autumn, riding their “hogs” with their long cirri blowing in the currents. And, while they aren’t so much riding as clinging for dear life, they do go fast. When their hog is sufficiently motivated, a manatee barnacle might top 20 mph—an unimaginable speed for the posers attached to the bridge pilings that pretend they are going fast in the rushing tidal currents. Manatee barnacles are the real deal; the 1%ers.

But the free-wheeling lifestyle comes with a price. Persistent gnawing of buck-toothed sheepshead fish and the constant sloughing of dead skin from the manatee’s thick hide take a toll on manatee barnacles. Their motto should be live fast and die young. For the next few weeks—months if they’re lucky—they’ll cruise the coves and eelgrass meadows of King’s Bay, flaunting the rules of civilized barnacle society. But by the spring warm-up, most will be dead.

Crystal River, 11/22/11: A marine biologist leans toward the reciever, closes his eyes tight and listens. He has been using this equipment for several years studying manatee vocalizations and knows most of the aquatic sounds that hum King’s Bay; but not this one. His brow furrows as he strains to hear the faint, unidentified squealing. He’s only heard it a few times before, and always when the manatees are arriving from their summer feeding grounds. He makes a puzzled notation in his field journal, “sound appears to be coming from the vicinity of some barnacles on the manatees back and sounds like....woo hoo ???”

Friday, February 10, 2012

Florida's Pompeii - Thoughts on Rodman Reservoir

Breaking news - there’s too much life in Ocklawaha River. So says the St. Johns River Water Management District (SJRWMD) and other State agencies tasked with "protecting" our waterways. It’s a recurring theme. In the 1960’s, the problematic life-form was a beautiful swamp forest growing on ground slated for a barge canal. So, after flattening a sixteen mile, 400 foot-wide path through the forest, they flooded the river valley to a depth sufficient to float the anticipated barges. Outside the cleared canal path, the remainder of the forest was left standing, to be killed by the flood waters. Soon, the reservoir was a forest of dead snags.

In the years following the valley's flooding, the dead trees decayed and toppled over, but only the parts standing above the water. Below the surface, the submerged stumps were preserved by the acidic, tannic water. The result is a submerged forest of trunks that appear to have been topped by a giant mower. In the deeper, downstream end of the reservoir these stumps stand 8 – 10 feet high from the reservoir bottom. For motor boat operators, these submerged trunks form a virtual mine-field where many propellers have met their end.

Decades have passed since construction on barge canal was halted in 1974 (it was officially de-authorized in 1990's). But, the reservoir remains. It turns out that the large, artificially maintained lake with its submerged forest of stumps is ideally suited to large-mouth bass. Enter the well-funded fishing and motor-boat lobbies and a handful of local legislators who have fought hard to keep this artificial fishing hole in place. As politicians and big business duke it out with environmentalists, Florida's tax payers continue to shell out nearly a million dollars per year for operations and maintenance and sixteen miles of the Ocklawaha Valley (including over 20 springs) remain submerged.

These days, all funding for Rodman Reservoir is used to artificially maintain the good fishing. High on the list of SJRWMD's management concerns is the overabundance of aquatic vegetation in the reservoir. The unnatural conditions created by this man-made pool have caused aquatic vegetation—mostly hydrilla—to grow out of control. Fish and fishing boats alike have trouble maneuvering.

To remedy this, SJRWMD is conducting a “draw-down” (partial draining of the water) to kill the vegetation. It’s a stressful time for the fish and other wildlife in the reservoir. But, for paddlers, these draw-downs (conducted every 3 - 4 years) offer a unique opportunity to explore the lost segment of this amazing river.

People who love the Ocklawaha visit the drawn-down reservoir the way relatives visit a family graveyard. They drift solemnly along the flowing brown path, pausing occasionally to contemplate the gnarled tombstones. Some appear sad. Others are introspective as they try to recall happy memories. Sometimes they look around, conjuring vague images in their minds, trying to juxtapose faded memories with this wasteland. Some are inspired to poetry. I did not know this part of the Ocklawaha before it was flooded. Still, the loss feels very personal.

In the past, I’ve called Rodman Reservoir “Florida’s Pompeii.” It seems like a fitting comparison when I see the field of ashen grotesques, frozen in their tragic, final moments. It’s also powerful image to use when I’m trying to describe the magnitude of what was lost when this reservoir was filled and what continues to be lost every year that it remains. But, frankly, some aspects of the comparison don’t fit. Pompeii speaks of screaming agony and the loss of all hope. The Rodman stump forest is simply a beautiful forest frozen in time. It's a quieter, gentler tragedy.

These days, I’m more inclined to compare the Rodman stumps to sculptures. Some days, paddling down the old river channel feels like a stroll through a museum gallery, moving from one gnarled grey masterpiece to the next. They are at once lifeless and full of emotion, like the “Hands” of sculptor Auguste Rodin. As the name implies, this series of clay sculptures are of hands and nothing more. Without the benefit of a body or a face to give expression, Rodin’s Hands convey the full spectrum of human emotions and experience—longing, playfulness, excitement, agony, sadness, love.

Likewise, the sinewy detail of many of the reservoirs stumps allows us to imagine the Ocklawaha forest the day it died. Elegantly curved stems of climbing aster and buttonbush rest among the folds of a bald cypress's flared buttress. We recognize the twisted, muscular trunk of a blue beech curving around the smooth bole of a red maple. Seven feet above ground the small tree leans against the finely checked bark of a green ash. We smell bay blossoms and dodder. We welcome the shade of a towering cathedral of cypress and ash and tupelo and revel in a thousand greens of summer (or was it the fiery hues of autumn? or maybe cool, airy winter?). We hear the hammering of a pileated woodpecker and a trio of squirrels chasing though the canopy. We hear the laughter of children splashing in Blue Spring. Let's ignore that ominous, sickening rumble in the distance.

It’s not all death in the drawn-down Rodman Reservoir. Reptiles are occasionally seen along the banks of the relict channel, though not as many as in the living river upstream and downstream from the reservoir. Wading birds, and wintering crowds of white ibis and American coots work the flats. Ospreys and bald eagles love this area as well. Of course, the only living trees we see are on the far bank. One, in particular, always draws my attention. It is a huge, solitary live oak growing on a spit of high ground near Blue Spring. Its massive size and long, gravity-defying limbs are powerful reminders of nature’s ability to endure and to heal--a fine contrast to the reservoir's constant reminder of our own capacity for bad ideas. It reminds me of another famous Rodin sculpture, “The Thinker.”