10 Recent Breakthroughs in Marine Biology

Small Sea Turtles Do More Than Catch the Drift
These loggerhead sea turtle hatchlings show off their strokes. © Lynda Richardson/Corbis

Parents shudder to think of their children as aimless drifters, yet until recently that's what marine biologists thought was literally true of some sea turtle hatchlings. But when researchers from the National Marine Fisheries Service in Miami used tiny satellite trackers to follow the movements of small green (Chelonia mydas) and Kemp's ridley (Lepidochelys kempii) wild-caught turtles, they were in for a surprise. Compared to a control group of free-floating inanimate objects, the young turtles moved faster and along different paths [sources: Putman and Mansfield; Zielinski].

This finding, along with an earlier study of loggerhead (Caretta caretta) hatchlings, is changing how we view the life cycles of young sea turtles. After hatching, many sea turtles, including the species studied, spend several years unobserved on the open ocean, a mysterious interim that marine biologists call the "lost years" [sources: Mansfield et al.; Putman and Mansfield; Skwarecki]. Based on certain evidence, such as small turtles occasionally turning up where ocean currents would naturally carry them, scientist believed that juvenile sea turtles engaged in "passive migration" at the whim of the sea. These two studies show that at least three species influence their fates by swimming.