Scientists have found a new way of determining the lifespan of turtles that could help biologists understand how fast turtle populations are growing or shrinking.

The study, carried out by The University of Western Australia, CSIRO and the Department of Biodiversity, Conservation and Attractions was published in the PLOS ONE Journal and will help support long-term turtle conservation as human activities increase.

Turtles live for a long time compared to most wild animals but putting specific numbers on their life span has been difficult. 

Some obstacles preventing an accurate analysis include only a limited number of turtles surviving their early years or making it to an old age, and the ones that do can be difficult to track.

UWA Professor Simon Jarman said the new method worked by analysing specific parts of about 40 genes in turtles that correlate with the lifespan of animals with bones, like turtles, mammals, birds, reptiles and amphibians.

“These genes have special short sequences called “CG” that can be used to determine the lifespan of five turtle species, ranging from 50 years in the flatback turtle, to 90 years in the leatherback turtle,” Professor Jarman said.

"The lifespan of turtles is important information because it defines how long they can breed for. If we know how many turtles reach adulthood and how long they live, we can estimate how many in a population can breed each year."

Professor Simon Jarman

Professor Jarman said many marine turtle species had been declining in numbers because they nest on beaches and beach habitat is being taken over by human activities all over the world. 

“The populations of most turtle species are shrinking, so knowing how fast this is happening and working out how we might stop it is important. Turtle lifespan is part of the information that we need to be smart about trying to live alongside them,” he said.

Professor Jarman said the new lifespan estimation method could be applied to a number of other species too.

“We hope to use it on fish and other marine creatures to help manage fisheries so that they last into the future.”