February 19, 2013
Protecting Sea Turtles From Climate Change Should Include Nesting Site Protection
Brett Smith for redOrbit.com - Your Universe Online
As various species around the world experience increasingly negative impacts from climate change, scientists are constantly looking for ways to inform the conversation around conservation.
A joint team of Australian and American researchers recently published a study in the journal Global Change Biology that shows how the official protection of key breeding grounds is vital to maintaining the resilience of many sea turtle species.
“To give marine turtles a better chance of coping with climate change, we have to protect their nesting sites and to address threats such as bycatch and coastal development,” said study co-author Mariana Fuentes from the ARC Centres of Excellence for Coral Reef Studies (CoECRS) and James Cook University.
“We have seen sea turtle populations decline dramatically in recent decades, and it is likely to get worse due to climate change, as they´re particularly vulnerable to it,” she added. “Climate change can affect their nesting beaches through sea level rise, stronger cyclones and storms; high temperatures can cause their eggs to die before they hatch, or produce an unnatural sex ratio and adversely affect their food sources.”
In the study, Fuentes and her colleagues surveyed 33 experts from the IUCN-SSC Marine Turtle Specialist Group about relative population size, rookery vulnerability and genetic diversity of sea turtle populations around the world. They also asked these experts to assess threats to the turtles, such as fishing activity, coastal development, and pollution.
The expert panel emphasized the vulnerability of breeding grounds and human activities are having the greatest effect on the turtles´ resilience to the forces of climate change.
Through their work, the researchers pinpointed the world´s 13 turtle conservation areas that are the least resilient to climate change. These fragile rookeries are distributed across three major oceans and are important breeding grounds for flatbacks, loggerheads, green turtles, leatherbacks, hawksbills, olive ridleys and Kemp´s ridleys.
“Eleven of the least resilient conservation areas that we identified are the ones most likely to lose their turtle rookeries,” Fuentes said. “This highlights the particular importance of protecting key regional nesting beaches and to legally protect areas that may be suitable for turtle nesting in the future.”
Fuentes noted policymakers and officials have several avenues for pursuing the resilience of different turtle species, including the protection of breeding grounds and the reduction of threats from climate change.
“At present there are three ways we can tackle climate-related threats,” Fuentes said. “We can reduce global greenhouse emissions, actively manage for direct impacts from climate change by manipulating the nesting thermal environment with shade, for example, and build the turtles´ resilience, that is, their ability to recover from the negative impacts.
“Reducing emissions is perhaps the biggest challenge, but even if we were able to cut greenhouse emissions immediately, it will not stop the already apparent and unavoidable impacts of climate change on turtles,” she continued.
“Also, we don´t know the risks of implementing actions, such as relocating, manipulating or managing turtle populations, or how effective these strategies are,” Fuentes said. “So until we understand more about the risks and effects of active strategies, we should focus on increasing the turtles´ resilience.
“Turtles have existed for millions of years and were here long before humans. It would be a complete tragedy if they were to become extinct as a result of our actions and our lack of care.”