There exists a presence in the ocean, seldom glimpsed in waking hours, best envisioned in your dreams. While you drift in sleep, turtles ride the curve of the deep, seeking their inspiration from the sky. From tranquil tropic bays or nightmare maelstroms hissing foam, they come unseen to share our air. Each sharp exhalation affirms, "Life yet endures." Each inhaled gasp vows, "Life will continue." With each breath they declare to the stars and wild silence. By night and by light, sea turtles glide always, their parallel universe strangely alien, yet intertwining with ours.
Riding the churning ocean's turning tides and resisting no urge, they move, motivated neither by longing nor love nor reason, but tuned by a wisdom more ancient--so perhaps more trustworthy--than thought. Through jewel-hued sultry blue lagoons, through waters wild and green and cold, stroke these angels of the deep--ancient, ageless, great-grandparents of the world.
Earth's last warm-blooded monster reptile, the skin-covered Leatherback Turtle, whose ancestors saw dinosaurs rule and fall, is itself the closest thing we have to a living dinosaur. Imagine an eight-hundred-pound turtle and you've just envisioned merely an average female Leatherback. It's a turtle that can weigh over a ton.
Pursuing such a creature requires traveling through time as well as across space. To fully understand the Leatherback and what it means to people, I traveled with those who still worship it, those tracking it with satellites, and those whose valuation of sea turtles merely reflects their own lust and cravings. Such travels bring you face-to-face with animals, villagers, fishermen, and scientists who've staked their whole lives to the species' tumultuous fortunes.
Of course, one must also travel with the creature itself, one-on-one. To follow the Leatherback is to experience the vast and magnificent oceanic realm that is the sea turtles' theater on Earth, encountering whales, sharks, tunas, and the gladiator billfishes that share the stage and play their roles. It is to hear the ancient whispering wisdom of these creatures' long histories of survival.
My main motivation, as always, was to explore how the oceans are changing and what that means for wildlife and people. To travel with the Leatherback is also to explore a critical dichotomy of the changing oceans: the Leatherback--that gravity-generating centerpiece of our narrative--has declined 95 percent in the Pacific during just the last two decades. Yet the good news is that in the Atlantic, sea turtle recovery is the mode, with some populations growing exponentially. Many people are now working to carry this success into the Pacific.
Nowadays seven sea turtle species stroke the ocean. In descending size they are: Leatherback, Green, Loggerhead, Flatback, Hawksbill, Olive Ridley, and Kemp's Ridley. (No one seems to recollect what riddle "ridley" refers to.) They swim warm and temperate seas worldwide, but Kemp's is restricted to the North Atlantic, and the Flatback dwells only in Australian waters. Sea turtles are big animals. Even the smallest adult ridleys pull the scale to eighty pounds, and adult Greens and Loggerheads sometimes reach over four hundred pounds (close to two hundred kilos). But the heavyweight among heavyweights, sumo champion among turtles, is the Leatherback, whose average weight is more than twice the Green and Loggerhead's maximum--and its record weight, five times as heavy.
Leviathan the Leatherback made science's acquaintance in 1554 when Guillaume Rondelet, a French physician, introduced it in his Books on Marine Fish, in which True Figures of the Fish are Presented. The Leatherback's Latin name, Dermochelys coriacea, means "leathery skin-turtle." That skin is a dark blue-black with whitish pointillist spots, like an Australian aboriginal painting. Its back, that thick, resilient shield, bears seven longitudinal ridges, in form very much like the streamlined, friction-shedding denticles covering the skin of sharks.
Though the shell is turtles' signature design feature--and all sea turtles except the Leatherback live within rigid shells--Leatherbacks have, in a sense, no shell. Their ribs do not meet or fuse but remain an open latticework. Rather than a hard-bone carapace shingled with scaly scutes, the back forms over a jigsaw mosaic of thousands of small, thin--only a few millimeters--bones, overlaid by a thick matrix of oily fat and fibrous tissue. The belly consists only of a fragile, narrow oval of bone that's filled in with an expanse of heavy fibrous tissue several centimeters (more than an inch) thick. Rather than a domed back meeting a flat belly, the whole animal is rounder, more barrel-shaped. In different languages the Leatherback's names refer to its shape. In the Caribbean, for instance, it's sometimes called Trunk or Trunk-back.
Of the Leatherback, superlatives abound, inter alia: Leatherbacks are the fastest-growing and heaviest reptile in nature, the fastest-swimming turtle, the most widely distributed and highly migratory reptile, and the only one that can be called "warm-blooded." In this and other respects, they seem halfway to mammals.
As a species, the Leatherback ranges more widely than any animal except a few of the great whales. As individuals, probably no whales range farther. How could they? Leatherbacks cross entire ocean basins, and then crawl ashore to nest. No whale can do that. And Leatherbacks dive deeper than whales. Certainly no land animal, including humans, can call so much of the world their native habitat and home. Leatherbacks range through tropical and temperate seas to the boundary realms of Arctic and Antarctic regions. That wide range, and their multiplicity of nesting sites, should make them extinction-proof. But they have their vulnerabilities.
I traveled with Leatherbacks and other sea turtles along the Atlantic seaboard of the Americas, from South America to the Canadian Maritimes, then in the Pacific from Central America north to central California and west to New Guinea. Leatherbacks everywhere are telling us that since the time hungry dinosaurs were a sea turtle's worst problem, it's been a shrinking world. Their mute plea, as they attempt to carry on as always, is that we will understand, while there's time, the connections within this water-bound planet. This ancient mariner who has seen both the fall of dinosaurs and the dawn of humankind, this master navigator now, ironically, needs us--the only creature who ever posed its species a mortal threat--to chart a path to its future.
Poet laureate Billy Collins says poetry should displace silence, so that before the poem there is silence, and afterward, silence again. A sea turtle, suddenly appearing at the surface for a sip of air, displaces water. And afterward, water still. This is the turtle's poetry, a wordless eloquence stated in silence and, in a moment, gone.
Copyright © 2006 by Carl Safina