Ocean News

How hard can it be to study turtles?

17th December 2009

More so than you might think.

Amongst marine researchers, the critically endangered hawksbill turtle is notoriously difficult to study in its natural habitat. Like tortoises, turtles are often viewed as slow, lumbering reptiles, but any scuba diver fortunate enough to see one in the wild will appreciate that encounters tend to be fleeting. These skittish creatures are usually seen darting into the blue, wary of any unfamiliar presence. Hawksbill turtles are typically cautious of anything larger than themselves due to the associated risk of predation, hence their tendency to avoid people and the subsequent problems faced when trying to study them.

Although their reproductive cycle is reasonably well understood from being so accessible when tirelessly digging their nesting pits on the beach, the difficulty of locating hawksbill turtles underwater, and crucially being able to observe them for any length of time, has meant that their feeding methods, prey preferences, social interactions and impact on their environment all largely remain a mystery.

However, Rainer von Brandis, an SOSF funded marine biologist, has managed to overcome this natural trepidation of human presence in a remote population of hawksbill turtles in the Seychelles, affording him the opportunity to gain unique insights to their behaviour and ecology. On an insular coral reef amongst the Amirante Islands Rainer found that he repeatedly encountered the same individuals over the course of several days’ diving.

These turtles were initially cautious of his presence and so Rainer was mindful to keep his distance, but they gradually seemed to habituate and eventually acted as though he weren’t even there, allowing him to approach within arm’s length and spend entire dives with them. In this way, Rainer has managed to familiarise himself with at least fifteen different individuals and collect otherwise unobtainable data. Eighty percent of over three hundred observation hours has been spent with three particularly accommodating turtles, which occasionally check whether Rainer’s scuba equipment is edible or use him as leverage whilst digging for food.

With these turtles effectively ignoring Rainer he has been able to gain unprecedented access to all their daily activities, revealing new aspects of their behaviour and just how important they truly are for maintaining coral reef biodiversity. Check back soon to learn more of what Rainer has discovered about the private life of the elusive hawksbill turtle and why it is so important they are protected.