At last, scientists have a way to follow sea turtles during their frantic first hours of life. Out of the seven known species of sea turtles, six are threatened or endangered, making it imperative to increase understanding of their life cycle and habitat needs. Improvements in satellite technology have shed light on the movements and behaviors of adult turtles, but as soon as baby sea turtles enter the water their next steps are unknown.
The question of where young sea turtles go after first entering the surf has dogged biologists for at least 80 years. Ross Witham, writing in American Zoologist in 1980, dubs it “The Lost Year Question.” Witham discusses many of the difficulties with juvenile turtle research, including their small size, agility, dark coloration that limits visibility, and technological limitations. Witham himself made an early attempt to answer the lost year question, tagging several lab-raised turtles, releasing them in Florida, and then waiting to see where they turned up. When returned tags came back from all over the Caribbean and Southeastern U.S., Witham hypothesized that the babies swam out far enough to be picked up by ocean currents, but was unable to prove it or fill in any details.
In the intervening years, scientists made great use of satellite technology to study adult turtles, filling in gaps in knowledge of the intervening years between hatching and returning to the nest. A 2005 study in Proceedings: Biological Sciences placed satellite tags on several adult leatherback turtles, watching them travel vast transects starting in Newfoundland and travelling as far south as Suriname. Besides their movements, the technology enabled the researchers to log all sorts of information about the turtles’ behavior.
Now, with any luck, the same level of detail can be applied to baby sea turtles as well, and the last secrets about their dispersal after hatching will be unlocked. Sea turtles live a very long time, and undertake incredible journeys across entire oceans before returning to their natal beach to lay their own eggs. Unfortunately, they face many threats along the way, from light pollution to overfishing. This new technology will hopefully one day help to mitigate those threats.
