Nav: Home

Climate change could bring short-term gain, long-term pain for loggerhead turtles

September 05, 2019

TALLAHASSEE, Fla. -- An overwhelming scientific consensus affirms that for thousands of species across the globe, climate change is an immediate and existential threat.

For the loggerhead turtle, whose vast range extends from the chilly shores of Newfoundland to the blistering beaches of Australia, the story isn't so cut and dried.

New research from conservation biologists at Florida State University and their collaborators suggests that while some loggerheads will suffer from the effects of a changing climate, populations in certain nesting areas could stand to reap important short-term benefits from the shifting environmental conditions.

In an investigation of 17 loggerhead turtle nesting beaches along the coast of Brazil, scientists found that hatchling production --the rate of successful hatching and emergence of hatchling turtles -- could receive a boost in temperate areas forecasted to warm under climate change. But those improvements could be relatively short lived.

"Even though hatchling success is projected to increase by the year 2100 in areas that currently have lower temperatures, it is likely that as climate change progresses and temperatures and precipitation levels approach negative thresholds, hatchling production at these locations will start to decrease," said study author Mariana Fuentes, an assistant professor in FSU's Department of Earth, Ocean and Atmospheric Science.

The study was published in the journal Scientific Reports.

During the incubation process, marine turtle eggs are heavily influenced by their environments. Air and sand temperatures can determine the sex of hatchlings, spikes in moisture content can drown developing embryos, and excessive solar radiation exposure can affect turtles' morphology and reduce their chances of survival.

In their study, the FSU researchers evaluated current and projected hatchling production under a variety of different environmental conditions throughout the expansive Brazilian coastline.

In the northern equatorial nesting beaches where temperatures already soar, the team found persistent and accelerating climate change will increase air temperatures and escalate precipitation beyond the thresholds for healthy incubation -- a major hit to hatchling production.

For the temperate beaches farther down the coast, climate change will bring similar increases in air temperature and precipitation. But, hundreds of miles from the equator, the effects of those changes look considerably different.

"These cooler beaches are also predicted to experience warming air temperatures; however, productivity is predicted to increase under both the extreme and conservative climate change scenarios," said former Florida State master's student Natalie Montero, who led the study.

Over the coming decades, as the climate shifts and temperatures climb, these conventionally cooler beaches will become more suitable for healthy loggerhead incubation. But if climate change continues unabated, "these beaches could also become too warm for successful production, much like the warmer beaches in our study," Montero said.

The researchers also stress that changes associated with a warming climate -- beach erosion, unchecked coastal development and environmental degradation, for example -- pose urgent threats to marine turtle nesting beaches at all latitudes, regardless of air temperature or precipitation.

And while contemporary and future shifts in climate conditions could benefit select loggerhead populations, well-documented warming trends suggest the long-term prospects of these and other ancient sea turtle species remain precarious.

"Sea turtles have been around for a long time and have survived many changes to the global climate," Montero said. "However, climate changes of the past took a long time, allowing sea turtles to adapt to the changing conditions. Today's climate change is happening very quickly, and therefore sea turtles must adapt quickly or perish."
This research was funded by the Florida State University Graduate School and the Winchester Fund at Florida State University. The work was a collaboration between Florida State, Projeto Tamar, the National Oceanic and Atmospheric Administration and The Leatherback Trust.

Florida State University

Related Climate Change Articles:

Fairy-wrens change breeding habits to cope with climate change
Warmer temperatures linked to climate change are having a big impact on the breeding habits of one of Australia's most recognisable bird species, according to researchers at The Australian National University (ANU).
Believing in climate change doesn't mean you are preparing for climate change, study finds
Notre Dame researchers found that although coastal homeowners may perceive a worsening of climate change-related hazards, these attitudes are largely unrelated to a homeowner's expectations of actual home damage.
Older forests resist change -- climate change, that is
Older forests in eastern North America are less vulnerable to climate change than younger forests, particularly for carbon storage, timber production, and biodiversity, new research finds.
Could climate change cause infertility?
A number of plant and animal species could find it increasingly difficult to reproduce if climate change worsens and global temperatures become more extreme -- a stark warning highlighted by new scientific research.
Predicting climate change
Thomas Crowther, ETH Zurich identifies long-disappeared forests available for restoration across the world.
More Climate Change News and Climate Change Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Erasing The Stigma
Many of us either cope with mental illness or know someone who does. But we still have a hard time talking about it. This hour, TED speakers explore ways to push past — and even erase — the stigma. Guests include musician and comedian Jordan Raskopoulos, neuroscientist and psychiatrist Thomas Insel, psychiatrist Dixon Chibanda, anxiety and depression researcher Olivia Remes, and entrepreneur Sangu Delle.
Now Playing: Science for the People

#537 Science Journalism, Hold the Hype
Everyone's seen a piece of science getting over-exaggerated in the media. Most people would be quick to blame journalists and big media for getting in wrong. In many cases, you'd be right. But there's other sources of hype in science journalism. and one of them can be found in the humble, and little-known press release. We're talking with Chris Chambers about doing science about science journalism, and where the hype creeps in. Related links: The association between exaggeration in health related science news and academic press releases: retrospective observational study Claims of causality in health news: a randomised trial This...