University of Georgia
April 2015
SREL sustainability study monitors Rainbow Bay

UGA’s Savannah River Ecology Laboratory has monitored the wetland life at Rainbow Bay since 1978. Fish-free isolated wetlands, above left, that hold water in winter through summer but tend to dry annually are extremely important breeding habitats for amphibians such as the larval spotted salamander, top right, and a female marbled salamander on nest, bottom right.

SREL sustainability study monitors Rainbow Bay

Record-holding study at Rainbow Bay documents amphibian, reptile population shifts, climate change impacts and environmental factors.

Did you know that the University of Georgia is a Guinness World Records holder? In 2000, UGA’s Savannah River Ecology Laboratory was awarded the record for having the longest daily monitored amphibian and reptile study in the world.

This study began 36 years ago on September 21, 1978, at Rainbow Bay, a 2.4-acre seasonal wetland on the U.S. Department of Energy’s Savannah River Site.

At that time, the word sustainability was not in the American dictionary or the American vocabulary. What you would have found in the dictionary in 1978 (Webster’s New World, Second College Edition) were the words sustain and sustainable, defined as to keep in existence; keep up, maintain or prolong.

David Scott, a research professional at SREL, is modest about his role as the human capital forging the study ahead in recent years.

“I’ve been involved, along with many others, in monitoring Rainbow Bay for the last 32 years,” said Scott. “The monitoring technique—a drift fence with pitfall traps around a wetland—is quite simple. What’s noteworthy are the tens of thousands of person-hours required to collect the data on a daily basis.”

The pitfall traps Scott describes are plastic buckets lodged into the ground with their rims open at the surface. They sit at the drift fence, a long continuous metal barrier that surrounds the wetland.

Curious intruders—amphibians and reptiles—fall into the buckets at night. The next morning, Scott rescues them from the traps, measures and marks them and gives them access to the wetland.

Post-breeding adults and their offspring are captured in these traps as they exit the wetland. To date, more than 25 species of amphibians and 40 species of reptiles have been captured at Rainbow Bay.

By now, you might be asking, “OK, interesting, but why study amphibians and reptiles every day?” The study was initiated at the request of the DOE because of its concern that the construction of a waste removal facility near the wetland might have negative ecological impacts on the environment.

Over time, a novel idea developed—a sustainability study that does not change. Instead, it evaluates shifts in population dynamics, the impact of climate change and environmental factors and, in the process, achieves record results from long-term data sets that could not be obtained otherwise.

“Once you see the population trends and patterns, you start to ask the question ‘what causes these things to occur?’” Scott said. “This relatively simple drift fence study spawned a whole suite of experimental studies and comparative studies at other wetlands. It has been the source of a lot of amphibian ecology.”

Through the years, the study has been a collective effort, with faculty, researchers and graduate students taking a significant role from checking traps to collecting data. The Rainbow Bay Project has been the source of more than 60 published scientific articles. They can be found at

—Vicky Sutton-Jackson, Savannah River Ecology Laboratory