Scientists in Panama have fitted capuchin monkeys with radio collars. / ASSOCIATED PRESS

By NATALIE ANGIER

BARRO COLORADO ISLAND, Panama - A group was tramping through the forest in pursuit of white-faced capuchins, those familiar organ-grinder monkeys with the wild hair, piercing eyes and impatient scowls. Capuchins are said to be exceptionally quick-witted .

“Nothing seems to slow them down,”said Margaret Crofoot, 29, a primatologist who is studying the monkeys.“They never stop moving.”

Dr.Crofoot and other scientists who work here at the Smithsonian Tropical Research Institute are thrilled with a new system for tracking their subjects that could help revolutionize the laborintensive business of field biology.

Called the Automated Radio Telemetry System, the method relies on seven 40-meter-high radio towers scattered across the island that can monitor data from many individuals simultaneously, 24 hours a day, all year long. Once an animal has been outfitted with a transmitting device, the towers can track its unique radio signature and, by a process of triangulation, indicate where it is on the island, whether it’s moving or at rest, what other radioendowed individuals it encounters.

The constant data streams feed into computers at a central lab building on the island, allowing researchers to stay abreast of far more animal activities than they could possibly follow through direct observation .

Scientists can tag and track katydids, orchid bees, monarch butterflies, even plant seeds.

“Automated systems like this are ushering in a new era of animal tracking,”said Roland Kays, another institute research associate. The application of radio telemetry towers, global positioning satellites and other cyberscapes to the mapping and deciphering of the natural world has spawned a new subdiscipline.“Movement ecology is the term being thrown around now,”said Dr.Kays, who is also curator of mammals at the New York State Museum in Albany.

Dr.Kays is applying the tracking system to explore the dynamic relationship between the island’s population of ocelots; the ruddy, snouty rodents called agoutis; and the island’s towering and thickly buttressed Dipteryx trees. The agoutis love Dipteryx seeds, and the ones they don’t eat immediately they bury for later consumption. The Dipteryx needs the agoutis to bury its seeds before ground beetles or other animals destroy them, but then the tree wants the rodent to conveniently disappear. Ocelots love agoutis; the rodents are their most important food source. The question Dr.Kays is asking: How many members of each sector are needed to sustain the correct balance.

Researchers admitted that the upkeep of a complex computerized network in the humid and decaying conditions of a tropical rain forest is always tricky. Moreover, tagging animals remains difficult, particularly when the subjects are smart and easily spooked, as capuchins are.

At the moment, only five of the island’s estimated 250 to 300 capuchins are fitted with radio collars, a figure that Dr.Crofoot hopes to double or treble. Once she is able to eavesdrop simultaneously on a representative sampling of the 15 to 20 capuchin social groups that roam the island, she can better address her abiding interest in intertribal politics.

“There have been decades of work looking at social relations within primate groups,”she said.“But primates have neighbors, and they’re with those neighbors over decades, so the question is, what are those relationships like?”

Early evidence suggests that capuchins are xenophobic but not imperialistic.“The tracking data indicate there’s lots of longdistance avoidance,”Dr.Crofoot said. The monkeys stay away from their versions of demilitarized zones, where one group’s territory overlaps with another’s.

The best way to win a war is not to start one in the first place: pure genius.