Every summer, Great Duck Island is invaded by thousands of Leach's storm petrels, ready to breed and nest. But even a skilled field biologist like John Anderson has rarely glimpsed the small seabirds, which hunker down in burrows on the island 12 miles off the coast of Maine and emerge only at night. To answer basic questions like how many chicks the birds typically rear or what they need in the way of nesting habitat, Anderson, of the College of the Atlantic in Bar Harbor, has had to get down on his stomach and stick an arm into the burrows, which scares the petrels and threatens the survival of their young.
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Then two years ago, Anderson and his team went high tech. Throughout the island, they set up a network of small, wireless sensors called "motes" that detect the birds as well as measure temperature, humidity, and barometric pressure. The battery-powered devices transmit their data by radio link to a solar-powered base station on the island and then to the Internet. "You can literally be anywhere in the world," Anderson marvels, "and know what's going on in burrow No. 43."
Matchboxes. Thanks to this new technology, many scientists are getting the chance to observe what was previously unobservable. Just as MRI technology revolutionized our ability to peer inside the body, the new networks are expected to shed much-needed light on planetary problems like climate change and how pollutants move through the environment, says Deborah Estrin, director of the Center for Embedded Networked Sensing at the University of California-Los Angeles. Other researchers are testing the devices for modeling earthquake damage and monitoring everything from vehicle movements in war zones to water use in agricultural fields.
But while "smart dust" is generating excitement, some people already are concerned about the dark side of what will undoubtedly be its expanded presence on the landscape. "It's a very intrusive technology and could be abused," says John Cozzens, the National Science Foundation's technical coordinator for CENS.
Sensors and computer chips have long been embedded in consumer products, whether cars or refrigerators. What's new is that because motes are wireless and battery-powered, they can be used in previously hard-to-access places and moved around at will. Before the technology takes off, motes may have to get smaller--currently, prototypes are the size of matchboxes. The devices also will have to become cheaper, more reliable, and more energy efficient. But there's little doubt that they could serve as ubiquitous information collectors. These networks of tiny communicating computers could even function as a new kind of Internet that, by merging with the physical world, would allow us to query almost anything--buildings, roads, rivers--for information.
The technology was jump-started back in 1998, when Kris Pister, then an engineer at the University of California-Berkeley and now CEO of Dust Inc., got funding from the Defense Department's Defense Advanced Research Projects Agency to develop tiny, intelligent sensing devices. "We had no idea what the applications would be and never in our wildest dreams expected it would lead where it has," he says. The initial challenge was to miniaturize the components, including the sensors, radio transmitters, batteries, and computer hardware. Programming the devices also was tricky because they needed to be both smart and energy efficient. UC-Berkeley computer scientist David Culler solved this problem by designing software that enabled the motes to "sleep" most of the time yet "wake up" regularly to take readings and communicate. "We didn't want lots of people to have to baby-sit the motes," says Culler.
