Health of amphibians in oil sand fields area assessed - via Herp Digest

Press Release by By Will Ferguson, WSU College of Arts and Science 6/5/7

The impact of pollutants from the world’s largest oil sand field on the health of amphibians marks the focus of a team of research biologists from Washington State University and Canada. The results of their study could apply to mining and fracking projects across both countries.

The scientists are among the first to study the effects of industrial pollutants from the Athabasca Oil Sands Project in Northern Alberta on the habitat, physiology, behavior and long-term health of wood frogs.

Scientists consider wood frogs a sentinel species, which means the overall health and number of wood frogs in the area can determine how similar organisms will respond to environmental changes.

Wood frogs are one of only three species of amphibians adapted to the cold and marshy oil sands region, located about 1,000 miles due north of Pullman. Known as the “antifreeze frog,” the wood frog can literally freeze during the winter and revive in the spring.

The researchers’ work will play a major role in future restoration efforts, required by the Canadian government after oil extraction in the region is complete.

“By Canadian law, when oil mining leases expire, the land must be returned to a functioning ecosystem through a process called reclamation,” said Erica Crespi, assistant professor in the WSU School of Biological Sciences and one of the lead investigators for the study. “Our job is to determine what impact, if any, pollutants from the mining sites are having on wood frogs so that we can effectively restore their ecosystem in the future.”

Crespi and Danna Schock, a disease ecologist at Keyano College in Ft. McMuray, Canada, are working with Environment Canada to conduct population surveys and collect tissue samples and tadpoles from various ponds around the mines for analysis.

The researchers’ preliminary results show wood frog hatchlings located in ponds nearest to the mines have reduced survival rates and are more susceptible to disease.

Additionally, tadpoles in the pond closest to the oil mines have higher levels of the stress hormone corticosterone and tend to retain more water and have more fat in their bodies. Frogs leaving the pond also have a higher prevalence of a pathogen called ranavirus, which can infect and destroy tissue throughout the bodies of amphibians, fish and reptiles.

“Even though there are frogs breeding in this pond every year, it doesn’t mean they are healthy,” Crespi said. “We are currently investigating the long-term effects of 

concentrations of salt and chemicals found in the pond closest to the mines on the wood frogs’ survival and reproduction.”

Crespi received a 2017 WSU International Research Travel Award from the Office of International Programs and the Office of Research to travel to the Athabasca oil sands this summer to continue collecting data for the study and to investigate the impact of recent forest fires on wood frog habitat.

She originally went to the oil sands  region in the summer of 2015 with Travis Seaborn, a biology graduate student, and Krysta Dawson, a biology undergraduate at the time who is now studying veterinary medicine at WSU. Together, they collected samples and live specimens for analysis back in Pullman to determine how oil sand pollutants were affecting the frogs’ health, as well as various behaviors like their response to predators.

“It was probably the coolest experience I had as an undergraduate,” said Dawson, who received a 2015 College of Arts and Sciences summer minigrant to accompany Crespi on the research trip. “I had never worked with a professor in the field before, and I got a lot out of the experience. It helped me to start thinking about the practical applications of what I learned in the classroom.”

For the past two years, Seaborn has worked with a team of undergraduate biology students in Pullman to raise tadpoles taken from the oil sands ponds in order to determine how pollution may be affecting their growth, mortality rates and behaviors.

“I supervise and manage a group of biology students who take care of the frogs and help analyze various behaviors like activity, food intake and response to predators,” Seaborn said. “So far, we aren’t seeing any differences in terms of behaviors between the frogs taken from ponds near the mines and ones further away, but we are seeing differences in disease prevalence and stress levels.”

The collaborative research could not only help in the restoration of the Canadian oil sands region, but could also help inform conservation efforts in the United States, Crespi said.

“Fracking is a different kind of mining but similar in that a lot of waste water is produced that contains chemicals and pollutants that could be detrimental to amphibians and other animals,” Crespi said. “Our hope is our work will provide new insights into what types of chemicals and industrial practices cause the most harm, so that we can conserve these species in Canada, the United States and elsewhere.”

Media contact:

• Erica Crespi, School of Biological Sciences, 509-335-3833, erica.crespi@wsu.edu

• Will Ferguson, College of Arts and Sciences, 509-335-3927, will.ferguson@wsu.edu