Sea turtle hatchlings emerge from underground nests on sandy oceanic beaches, scramble to the sea, and swim toward the open ocean in a migration lasting several days. During the migration, hatchlings quickly establish a seaward course, then hold this heading even after they swim beyond sight of land. Little is known about how hatchling sea turtles can maintain a straight course through a vast ocean that contains no obvious landmarks. Recent experiments have revealed that hatchling loggerhead sea turtles from the Atlantic coast of Florida can detect the magnetic field of the earth and use it as a cue to guide their migration. Dr. Lohmann's experiments are designed to study the newly discovered magnetic compass sense of sea turtle hatchlings and to provide insight into how sea turtles use magnetic cues in navigation. All species of sea turtles are now either endangered or threatened. Dr. Lohmann's research is expected to provide information useful to conservation workers trying to save sea turtles from extinction. In addition, it is expected to help scientists understand how other migratory animals (such as birds, fish, and whales) use information from the earth's magnetic field to navigate.
