I’m kneeling on a sandy beach in Costa Rica on a balmy January night helping biologists administer an ultrasound to a leatherback sea turtle. They are hoping to learn more about her reproductive cycle, to better protect populations of this endangered reptile at its nesting beaches around the world. The turtle has come ashore to lay her eggs, as her kind have done since dinosaurs roamed the earth. I watched as she hauled her enormous bulk up the beach, pivoted slowly around to face the ocean, and began scooping out an oval pit in the sand with her hind flippers. She soon entered her egg-laying trance, a quiescent state in which she remains for an hour until she covers over her nest and heads back to the surf.
In her reverie, she takes no notice of us as we get to work. We unpack the equipment, which looks like a desktop computer, and set it down in the sand just behind her. A switch is thrown, and flickering light from the screen lights up the turtle’s hind end. Two of us, one on each side, hold down her huge front flippers to ensure that she doesn’t start flinging sand in our faces when she begins concealing her nest. Those oarlike flippers can toss any one of us aside like so much flotsam, but they lie idle at her sides. I feel for her in her labor. Her weight makes it difficult for her to breath, and she sucks in air in great gasps. Tears designed to carry away excess salt dribble like saliva from her eyes, making her look as if she is crying from the strain.
We wait while she drops about 100 moist, white eggs into the nest. When she is finished, David Rostal, a biologist at Georgia Southern University, carefully moves the ultrasound probe across her skin over her uterus. Though I am familiar with ultrasounds, having watched the development of my own two babies, I cannot decipher the picture that forms on the screen. To Rostal, however, it reveals whether she has mature ovaries bearing preovulatory vitellogenic follicles-that is, whether she will return later in the season to lay another batch of eggs.
Notwithstanding my familiarity with ultrasounds, I find it truly incongruous to witness one of the most modern of medical tests being used on one of the most ancient of animals. Yet such scenes are becoming increasingly common. Today, on lonely mountaintops, in remote stretches of rainforest, and far out in the oceans, scientists are turning to all manner of high-tech tools to help them study threatened wildlife. Techniques range from tracing family trees of endangered species by analyzing their DNA to using video cameras strapped to sperm whales to film giant squid in their natural environment. In many cases, these advanced technologies are allowing scientists to investigate aspects of ecology, physiology, and behavior that they were never able to investigate before. And by enabling researchers and wildlife managers to identify crucial missing links in animal life cycles, the techniques are bettering endangered species’ chances for survival.
The work taking place with leatherbacks on this beach-Playa Grande on Costa Rica’s Pacific coast-is a case in point. For on that half-mile-long stretch of sand, biologists are making use of perhaps more high-tech gadgets than any other biologists working on any other animal. And with these tools they are answering a sea of previously unanswerable questions about the turtles-and so learning how remarkable they are and what kinds of conservation measures may help them.