Well, not exactly. What actually happens is that radio signals identifying the turtles' locations are transmitted from small devices attached to the animals' shells. National Oceanic and Atmospheric Administration (NOAA) satellites relay the signals to a ground station, and updates on the turtles' migrations are e-mailed to researchers.

Satellite tracking allows the turtles' positions to be calculated to within 150 meters (500 feet), even as the animals cross hundreds of miles of ocean. "It provides you with information that's impossible to get in any other manner," says Schroeder, who is national sea turtle coordinator for NOAA Fisheries and member of a team that has been tagging loggerhead turtles on the coast of Florida in recent weeks.

The team placed transmitters on five loggerhead turtles last year, and is now expanding the total number of tagged turtles to 19. The project is a joint effort of NOAA, the U.S, Fish and Wildlife Service, the Florida Fish and Wildlife Conservation Commission, and the nonprofit Caribbean Conservation Corporation.

Loggerhead turtles live mostly in the water, but migrate to beaches in the summer to build nests and lay eggs. The current research aims to find the location of the "resident feeding habitats" where the turtles spend most of their lives, and the routes they take between these habitats and the nesting beaches.

Such information may help conservation agencies protect loggerhead populations, which have been declining due to accidental capture by shrimp trawlers, among other causes. "When we understand more about the routes they travel, we can better assess what threats they might face along those routes," says Schroeder.