How to begin understanding the way a trout sees the world

By Scott KimJul 1, 1999 5:00 AM


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LEFT: Hands off! Unlike the river cooter above it, this alligator snapping turtle could easily take off a finger.RIGHT: A West Coast sea nettle propels itself with pulsing contractions.Photographs by Kim Hubbard

Standing hip-deep in a mountain stream or lying back in a rowboat, a rod tucked under your arm, have you ever wondered what's going on beneath your knees? If so, a visit to the Tennessee Aquarium in Chattanooga may be in order. "Lots of fishermen come here," says Jackson Andrews, the aquarium's director of operations and husbandry. The world's largest freshwater aquarium traces the path of a drop of water as it journeys from the headwaters of the Tennessee River to the Gulf of Mexico.

Visitors begin their journey above water, in the Appalachian Cove Forest exhibit. At the top of the building, under a tall, pyramidal skylight, bobwhites and bluebirds call to each other above the crash of a waterfall. Cardinals nest among leafy branches. It's hot and humid here in July, but come December, ice will form on the falls. Strolling through the forest, visitors pass a knot of heavily draped snakes--northern copperheads, timber rattlesnakes, and black rat snakes. (They're behind glass.) Two river otters tussle as if it's morning or doze as if it's afternoon. But few fish are in evidence until visitors pass through a revolving door to the aquarium's spiraling central ramp, flanked by tanks.

The first, the Mountain Sink exhibit, shows the waterfall from beneath. Bubbles from the falls stab downward into deep, cold water, where rainbow and brook trout circle and feed. Like others, this tank reaches through several turns of the ramp, allowing visitors to see how the fish sort themselves by depth. Farther along, an underwater view shows otters thrashing up bubbles with their thick tails.

Exhibits continue along the Tennessee River as it joins the Ohio and Mississippi Rivers on its way to the sea. One gallery explores human influences, with a 145,000-gallon tank devoted to man-made Nickajack Lake. Monstrous catfish graze at the bottom among flooded forests and roads. Under another skylight, the Mississippi Delta gallery re-creates a Louisiana bayou, complete with ducks, snakes, alligators, and alligator snapping turtles--including a 150-pound male with a fierce pout. The drop of water reaches its final destination in the Gulf of Mexico tank. Here, 40 marine species, including barracuda, stingrays, bonnethead sharks, lookdowns, and a green sea turtle, circle through mangrove roots and coral.

With their extravagant shapes and colors, the saltwater fish in the Gulf of Mexico exhibit are a relief after tanks of cookie-cutter trout and bass. A travelling exhibit of delicate, glowing jellyfish, on view through early January, adds variety. In a circular tank, young moon jellies revolve like tiny, pulsating umbrellas, while West Coast sea nettles trail their ruffled streamers.

But freshwater fish come in plenty of forms, as the Rivers of the World gallery proves. There are red-bellied piranha, spangled cannibals of the Amazon; puffers from the Congo; prize koi (goldfish to you) in dozens of colors and patterns, bred from carp that swam long ago in Japanese rivers; and a vast beluga sturgeon from the Russian Volga whose protective bony skin plates evolved before fish had scales.

For those who would hook fish, the best part of the visit may be watching divers in the tanks at feeding time. Volunteers in wet suits tuck food into the eager mouths of trout, turtles, an 80-pound catfish, and a 25-inch bass--the ones that didn't get away.Tennessee Aquarium

Island of the Sharks A production of NOVA/WGBH Boston and Howard Hall Productions. Running Time: 40 Minutes.

Three hundred miles off the coast of Costa Rica, a lone uninhabited island shaggy with rain forest lifts its shoulders from the ocean. An underwater volcano formed the dramatic crags above and below the water's surface, locking into the rocks a distinctive magnetic signature that calls to migratory sea creatures. From hundreds of miles away they flock to the island: manta rays with their needlelike tails, schools of hammerhead sharks 400 strong, and a team of filmmakers armed with IMAX cameras and an endless store of patience.

(c) 1999 NOVA/WGBH Boston/HHP; photograph by Howard and Michelle Hall

The result, a meditative portrait of the Cocos Island marine ecosystem, will open at specially equipped theaters and science centers across the country. The film keeps to the tradition of nature documentaries, observing animals as they hunt, eat, court, spawn, or flee. But its size makes a qualitative difference: a screen several stories high drenches the audience with images. It's so big that viewers have to turn their heads to take in all the action, as if they were in the water among the fish. The effect is even more dramatic in theaters with dome-shaped screens, where sharks, rays, and the paddling feet of seabirds pass by overhead.

Despite the title, there are no gaping jaws in Island of the Sharks. The sharks shown here mostly pick on fish small enough to swallow in a bite or two. And they share the screen equally with their cuddlier neighbors: turtles, eels, starfish, coral. Nevertheless, the hunting scenes are among the movie's most dramatic. In one, sea lions and marlins herd sardines and other small fish into a bait ball, a glittering cyclone that gets tighter and tighter as outliers dive to the center for safety. Dramatic music increases the tension while the hunters snap up the silver fish one by one, until nothing is left but floating scales.

Cocos predators make their living at the top of a food chain that's supported by nutrients carried up from the deep in rising currents of cold water. Large predators hunt fish, which graze on microscopic plankton fertilized by the nutrients. Climatic disturbances such as El Ni–o can disrupt the chain by keeping the rich water from rising. The film's story, such as it is, revolves around one such lean period, when Cocos dwellers scrounge for food. But on the whole, Island of the Sharks is rather aimless, prowling round and round the same rocks like a shark looking for dinner.

What the film lacks in plot, however, it makes up in action. A house-hunting hermit crab finds a new shell, knocking first to make sure it's empty before moving in. A well-camouflaged flounder pretends to be part of the seafloor as it grabs rainbow wrasses, then gets attacked by a whitetipped shark. A predatory mantis shrimp spoils a budding romance between a pair of blue-spotted jawfish by swallowing the female. Cushion stars slide and tumble across the seafloor in a time-lapse sequence, accompanied by vaguely Latin music and what sound like castanets. But the most poignant scene is the simplest: hundreds of hammerheads undulating gracefully overhead as they return to their island haven.

--Polly Shulman

Against the Tide: The Battle for America's BeachesCornelia Dean. Columbia University Press, 1999, $26.95.

The Seacoast Reader Edited by John A. Murray. The Lyons Press, 1999, $30; $17.95 paper.

The strip of sand where land meets sea exerts an extraordinary hold on ordinary humans. By the year 2000, demographers estimate, 80 percent of Americans will live within an hour's drive of a coastline. Most people love the shore without having any idea how beaches are formed, and few may fully appreciate how building near the shore alters beach ecology. But Cornelia Dean, a science journalist, does know. Her new book, Against the Tide, explains what happens when we love beaches too much.

Over the past century, coastal geologists have come to understand that beaches come and go with a logic of their own. Human practices profoundly disrupt this process. When rivers are dammed, forcing runoff into concrete washes, we lose the sediments that replenish coastlines. When we build close to the shore, we not only risk ruin by storms but also disturb the forces that permit sand to accumulate and redistribute naturally. The long-settled coast of New Jersey, for example, has been struggling to maintain its beaches for nearly a century. Building seawalls in the hope of saving homes from encroaching tides and storms ultimately doesn't work because the beach is starved of natural sand. And while structures called groins--designed to alter currents and trap sand--may save one stretch of beach, they so disrupt sand flow to neighboring beaches that somebody else ends up with a sand strip. Naturally, this massive redistribution of sand, often running into hundreds of thousands of cubic tons, is not easy to study, let alone to alter or even reasonably predict. One researcher says that it's probably easier to go to the moon than to understand the physics of the near seashore.

Dean's story is grim and often repetitive. It can be tedious, but she clearly loves her subject. On that score, her sentiments are much in tune with another, far more accessible beach book--The Seacoast Reader, a wide-ranging collection of essays. The powerhouse of the bunch is Barry Lopez's description of the stranding of 41 sperm whales on an Oregon beach in 1979. He reconstructs the scene--the onlookers who marvel and grieve, the scientists who study and dissect, the park personnel who must police the site and dispose of the corpses. And his images of the dying whales are unforgettable: the moist breath from the blowhole, the large purple eyes, the extraction of a fetus 15 feet long.

A piece by Nancy Lord describes a day spent fishing for a living in Alaska. Like Lopez's, the article tackles real-life problems far from the shopworn rapture that nature essays catalog. She and her partner haul fish from the nets, often vying with seals for their catch. The work is hard and the yield is not plentiful. At day's end, she scrubs dried fish scales from her arms. "Better than gold stars," she writes, "they're the medals that remind us how we live with fish."

The book contains other surprises, like Mark Twain writing about a trip to Hawaii, or Daniel Duane on surfers trying to catch--and survive--monster waves. On the whole, these are private, life-affirming epiphanies, while Against the Tide describes a far more conflicted relationship to the coast, comprising as much fear, pride, and frustration as wonder. (Dean's opening chapter on the hurricane that flattened Galveston in 1900--this country's deadliest coast disaster--and the Herculean effort to rebuild the town, is worth the price of the book.) Despite their differences, these two volumes share a long-standing human tradition of nature worship and an awareness that what we most relish, more than the sting of salt air or the caress of sand, is the play of forces far beyond our control.

Order Against the Tide from Amazon.com.

Order The Seacoast Reader from Amazon.com.

--Sarah Richardson

Primo Levi: Tragedy of an OptimistMyriam Anissimov, translated by Steve Cox. The Overlook Press, 1999, $37.95.

Few people have had as intimate a relationship with chemistry as Primo Levi, whose gift of writing brought the subject to life. Chemistry, in turn, saved his. Imprisoned in Auschwitz, the young Italian chemist was granted a tenuous reprieve as a technician in the laboratory of an I. G. Farben rubber factory built by slave laborers on the camp's grounds. After the war, Levi turned his analytic eye to the horrors he had survived: examining, weighing, and questioning how that world came to be.

Myriam Anissimov reveals her own analytic abilities and meticulous research in the first comprehensive biography of the gentle humanist to be published since his death in 1987, including illuminating accounts of the Jewish community in Turin, Levi's hometown.

Born in 1919, Levi grew up in a secular Jewish family and rarely turned his attention to his heritage until forced by a rising tide of anti-Semitism. Although he graduated summa cum laude from Turin's Chemical Institute, Mussolini's anti-Jewish laws prevented him from making his living as a chemist. After brief service with a band of poorly armed partisans, he was captured and deported to Auschwitz. From his earliest days in the camp, the half-starved and often beaten Levi was determined to mentally record his irrational world "with the curiosity of the naturalist." Following the liberation he returned to Turin, determined to testify against his tormentors and bring them to judgment.

"It seemed to me that I would be purified if I told [the] story [of Auschwitz]," Levi later wrote. "And I felt like Coleridge's Ancient Mariner, who waylays on the street the wedding guests going to the feast, inflicting on them the story of his misfortune." Levi's early concentration camp account, Survival in Auschwitz, is written in clear tones with a scientist's careful regard for the truth. "I am alive," he wrote in a later preface to the book addressed to German readers. "And I would like to understand you in order to judge you."

Yet Levi did not confine his writing to Holocaust experiences. In intervals snatched from daily work as a chemist and in retirement, Levi turned his attention to topics as diverse as literature, astronomy, philosophy, the dignity of manual labor, and the wonder of butterflies, beetles, and fleas. His most celebrated and popular work, The Periodic Table, is an imaginative meditation on the chemical elements. It begins with argon and ends with the fantastic adventures of a carbon atom as it dances through the environment, landing at last in the author's brain as he writes the book's final sentence. Levi also wrote essays and short stories, translated Kafka into Italian, and, with wry humor, dabbled in science fiction, once predicting the perils of virtual reality. He also contributed to the newspaper La Stampa. His last article, published two weeks after his death, was a whimsical interview with a pair of spiders eager to eat him.

Threatening images of spiders, Anissimov notes, recur intermittently in Levi's work. That one surfaced so close to his death was probably not coincidental; tormented by survivors' guilt, Levi had committed suicide. Yet the man who gazes out from this moving, inspiring book is not grim; he is hopeful, and fascinated by the world, even at its darkest hours.Order from Amazon.com.

--Josie Glausiusz

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