Tennessee Aquarium leads effort to develop interactive map of world's turtle communities - via Herp Digest

by WTVC- Tuesday, November 19th 2019

CHATTANOOGA, Tenn. — (Editor's note: This story was submitted to WTVC by Casey Phillips of the Tennessee Aquarium):

In the midst of what has been called the planet’s sixth mass extinction, many scientists describe the rate of species loss on earth as having reached crisis levels.

Faced with the epic challenge to halt, or at least slow, the disappearance of species, conservationists must make the best use of every dollar and minute of time. To do this, conservation efforts are often focused on biodiversity “hotspots,” a method that has proven effective in targeting species-rich, at-risk regions.

Yet, for all their benefit in guiding conservation projects to areas of need, hotspots leave something to be desired when used to direct safeguarding efforts for groups of animals or plants other than those upon which the hotspot is based.

“Hotspots have been proven very effective at directing conservation efforts,” says Dr. Josh Ennen, a biologist with the Tennessee Aquarium Conservation Institute. “But for groups of animals or plants with a different evolutionary history, such as turtles, hotspots might not accurately reflect the species richness patterns of the species you’re trying to save.”

To more accurately locate — and thus conserve — at-risk species, conservationists need a more data-driven approach that is specific to the plants or animals they’re seeking to help.

Freshwater turtles are one of the world’s most-imperiled groups of animals, with about 60 percent of the world’s 360-odd species either threatened or extinct. General imperilment and relatively low species count make turtles ideal candidates for testing a more-accurate, statistics-based method of mapping their distributions across the planet. 

A potential solution to this conundrum appears in an article published in the latest issue of the academic journal Biological Conservation. An international group of scientists led by Ennen and including Conservation Institute Geographic Information Systems Analyst Sarah Sweat processed data on the distribution of turtles around the world to generate an interactive map that defines the boundaries for “communities” of related turtle species.

The map identifies 63 global turtle regions, highlighting several as high-priority targets for ecologists based on conservation value and several metrics of biodiversity.

In addition to re-confirming the importance of previously identified turtle hotspots such as the American Southeast and Southeast Asia, the map finds that some turtle-rich areas actually consist of multiple, unique communities. Rather than a uniform swath of color, for instance, the map depicts the southeastern corner of Asia as six distinct communities rendered in various shades of green.

“It’s important to know that it’s multiple unique assemblages and not one giant collection of turtles,” Ennen says. “Another unique thing our map shows is the importance of turtles in Southeast Asia extends farther north into China than what others thought. We identify the Yangtze River and several coastal rivers in China that are very important for turtle conservation.”

Collaborators in the study included researchers from:

• University of California, Davis (Davis, California)
• Chiapas University of the Sciences and Arts (Chiapas, Mexico)
• U.S. Geological Survey
• Chelonian Research Foundation (Lunenburg, Massachusetts)
• Earlham College (Richmond, Indiana)
• Weber State University (Ogden, Utah)

Digging deeper into known hotspots to identify groupings of related turtle species will be crucial to future conservation efforts. This will be especially true in the future as new species are identified in lesser-studied regions such as Central Africa. Because the map can be updated to reflect new data sets, the boundaries of the communities defined on the map could be reshaped and entirely new ones could be established to ensure the highest degree of accuracy for future conservationists.

With updated, species-specific knowledge in hand, conservationists will be able to evaluate and tailor plans of action for each unique community rather than acting less efficiently by painting with too broad a brush, Ennen says.

“Money to do boots-on-the-ground research work to conserve turtles is very limited,” he says. “When you look at large-scale analyses like with this paper, what we’re trying to do is figure out how to divvy up the pie and help people figure out where to spend their money to get the most conservation effort out of their conservation dollar.”