Scientists warn of climate change risk to marine turtles

February 20, 2007

North American marine turtles are at risk if global warming occurs at predicted levels, according to scientists from the University of Exeter. An increase in temperatures of just one degree Celsius could completely eliminate the birth of male turtles from some beaches. A rise of three degrees Celsius would lead to extreme levels of infant mortality and declines in nesting beaches across the USA.

Research published this week in the journal Global Change Biology analyses 26 years of loggerhead turtle nesting and climate data and compares the findings with models for future temperatures. The study shows just how vulnerable marine turtle populations are to changes in temperature. The sex of marine turtle hatchlings is determined by the temperature of eggs during incubation, with warmer temperatures producing females and cooler conditions producing males. Temperatures during nesting also need to be at the right level for eggs to develop healthily and hatch successfully.

'We are stunned by these results and what they could mean for the species in the future,' said Dr Brendan Godley of the University of Exeter's School of Biosciences. 'In particular, we're concerned that populations that are already predominantly female could become 100% female if temperatures increase by just one degree. This is a major issue for nesting populations further south, in Florida, for example, where males are already in short supply.'

The research team recommends that conservation efforts are focused on protecting northern breeding grounds. While in Florida, 90% of hatchlings are female, in North Caroline 42% are male and scientists believe some of these males currently travel south, bolstering southern populations. A decline in male turtles in northern populations, as a result of global warming, could potentially impact marine turtles across the continent. ‘We take this as an important step in identifying essential thermal habitat for marine turtles,’ said study co-author Dr. Matthew Godfrey, of the North Carolina Wildlife Resources Commission. ‘It highlights the need to establish measures to specifically protect male-producing beaches.’

Dr Brendan Godley continued: 'In the face of climate change, it's essential that we prioritise the protection of sites that produce males not only for local breeding success, but to help support potentially vulnerable populations further south.'

This work was carried by the University of Exeter in partnership with the Bald Head Island Conservancy and the North Carolina Wildlife Resources

Source: University of Exeter

Explore further: Climate is changing fast in West Antarctica

Related Stories

Climate is changing fast in West Antarctica

November 23, 2015

When the ship pulls up at Palmer Station each Antarctic spring, the arriving scientists glance up at the massive glacier that covers most of Anvers Island. It has been retreating about 7 meters per year, and this year is ...

California's fish populations are declining

November 3, 2015

The California Current is home to many marine animals, including marine fishes, which are the most diverse vertebrates on Earth and critical to marine ecology. Two fishery-independent data sets reveal strikingly similar trends ...

Antarctica's wildlife in a changing climate

October 27, 2015

Despite being one of the coldest, most inhospitable places on Earth, Antarctica hosts a wealth of biodiversity, and its remoteness and extreme climate have lent a certain amount of protection to the many species that call ...

Recommended for you

Amazon deforestation leaps 16 percent in 2015

November 28, 2015

Illegal logging and clearing of Brazil's Amazon rainforest increased 16 percent in the last year, the government said, in a setback to the aim of stopping destruction of the world's greatest forest by 2030.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.