Turtle hatchling highways

12april2012
Source: scientias. nl
Ocean currents serve as 'highways' for young turtles: this was discovered in recent research. These highways bring the newly hatched turtles more quickly into deeper, safer water.
Scientists investigated the leatherback turtles of Costa Rica, about which quite a bit was already known – except regarding the turtles’ lives in the period between the hatchling phase and adulthood. Female leatherbacks lay their eggs on the beach. When the eggs hatch, the young turtles make their way to the water. During this trek, and after they have entered shallow waters, the animals are very vulnerable and are easy prey. It is important that they get into deep, safe water quickly. The researchers suspected that the current played a role in this fast-track to safety.

In an experiment, objects were put into the water, both in places where many turtles hatch and in places where few or no eggs are found. The objects launched where many hatchlings begin their lives were carried away quickly by a current. After about a month and a half, the objects had already been swept 1500 kilometres away. The objects launched where no or few turtles hatch, however, remained near the coast. Young turtles that hatch at these locations have a smaller chance of survival.

Evolution, according to the researchers, is the reason that most leatherback eggs are laid on the ‘favourable’ beach: the animals hatched there were more likely to survive.

The leatherback turtle is seriously endangered. The scientists involved in this study emphasize that knowledge about all life phases of this animal is essential to the protection of these turtles.