A recent study on baby turtles challenges previous assumptions that they drift with ocean currents during their ten-year journey toward maturity. Instead, solar-powered tracking devices revealed that baby turtles are actually active swimmers that choose their swimming directions.
Biologists knew that baby turtles use to vanish in their first ten years, which were called their “lost years,” but they thought that they were spending all this time drifting. Satellite-connected tags attached on the backs of 44 baby turtles found in the Gulf of Mexico showed another thing.
Scientists learned that turtles and the buoys they tracked as a reference point have very different swimming patterns and diverge quickly. The study was conducted to help environmentalists better protect the endangered creatures.
Currently all seven species of marine turtles are on the verge of extinction or threatened.
But attaching a tracking device to the elusive baby turtles was easier said than done. Researchers sometimes went on a 62-mile voyage to catch none. But other times they were lucky.
“Some trips there’d be a patch of them – 10 little turtles all together. But it took a while to get the sample size that was needed,”
said Dr Nathan Putman, from the NOAA’s Southeast Fisheries Science Center.
However, even when they did came across some turtles, many times those weren’t the right turtles. The team was mainly looking for Kemp’s ridley turtles, which are a very endangered species.
Instead, there were plenty of green sea turtles which do not nest on the Gulf of Mexico’s shores like the Kemp turtles do, but about 1,000 miles away, on the beaches of Costa Rica.
Dr Putman acknowledged that in the first year of research, his team didn’t tag green turtles because they thought that they would not be able to find enough to build a relevant sample. Yet, after learning that these turtles were very abundant they switched their investigation toward them.
Overall, researchers managed to tag 24 green turtles and 20 Kemp’s ridley turtles with ages ranging between six months to two years. Every time they tagged a baby turtle, researchers released it near a couple of buoys that were also carrying GPS trackers.
As a result, the research team could catch a clearer view on the turtles’ swimming patterns and learn whether they were drifting, like the buoys did, or actively swimming. They were surprised to learn that the tracks showed that drifters and turtles quickly diverged and went to completely different directions.
However, the team didn’t bust the myth that turtles are slow swimmers. By taking into account current ocean models, scientists found that baby turtles didn’t swim faster than a few centimeters per second. Nevertheless, they did compensate with their persistence, which amazed biologists.
Unlike satellite-tracked buoys, baby turtles had a clear direction in their minds when they swam around the Gulf of Mexico. That’s how researchers drew the conclusion that turtles do not just go with the flow and let ocean currents set their swimming routes. Instead turtles are very determinate and persistent swimmers even from their early years.
Image Source: Virginia Key Beach Park