Turtle, Dugongs ‘at risk due to climate change’

WASHINGTON - Scientists have revealed that the northern Great Barrier Reef (GBR) and Torres Strait region, is under immense pressure due to climate change from human actions such as fishing, hunting, onshore development and pollution.

“Depletion of turtle and dugong numbers increases their vulnerability to other threats and lowers their ability to cope with climate change,” said Mariana Fuentes of the James Cook University.

Fuentes said that turtles in particular are vulnerable to the effects of climate change, which include decreases in hatching success, loss of nesting areas and overheated beaches, which will decrease the turtles’ reproductive output and may significantly alter the sex ratio of their offspring.

Fuentes’ research into the green, hawksbill and flatback turtles and well as dugongs in the northern GBR and Torres Strait is seeking to establish priorities for the management of marine megafauna to increase their resilience to climate change.

“Managers face the challenge of addressing the direct effects of climate change, as well as ongoing threats that dugongs and sea turtles face throughout their geographic range.

Of particular concern is the effect of climate change on the gender balance of turtle population.

Fuentes said: “The temperature of the beach sand determines the gender of the hatchlings - warmer sand produces more females while cooler sand produces more males.”

“Under current conditions the nesting grounds are already producing more females. With an increasing temperature, these turtles are at risk of stretching out the ratio, though we can’t yet predict exactly when it will cause an unbalanced population.

“Turtles and dugongs have numerous roles - apart from their cultural and spiritual significance to the indigenous community, they are important for the tourism industry. Being at the top of the food chain also means that they have high ecological significance,” she said.

The loss of these species would have a huge impact on the northern Australian marine environment and on indigenous communities, she warned.

The results of the research were presented at the Academy of Science’s Shine Dome. (ANI)