08/19/2024 | Press release | Distributed by Public on 08/19/2024 07:53
By Lynne McCarthy
VCU Life Sciences
The Atlantic sturgeon is making a comeback in the James River, with Virginia Commonwealth University researcher Matt Balazik at the forefront of those efforts. This summer, he took his expertise overseas, where the United Kingdom hopes to reintroduce the prehistoric fish that has played notable roles in the history of both countries.
Balazik, Ph.D., research faculty at VCU Rice Rivers Center, led a team from the Zoological Society of London as it conducted research on two rivers in June. Sturgeons are considered "royal fish" in the U.K. and legally are property of the Crown. Two centuries of overfishing - on the James here, where the fish sustained English settlers, and on rivers in Europe - depleted sturgeon populations and their habitats. Now they are declared an endangered species in the U.S. and critically endangered in Europe.
ZSL and other members of the U.K. Sturgeon Alliance have begun work to determine if any U.K. rivers will be suitable as sturgeon habitats. In enlisting Balazik's expertise, the ZSL was building on a collaboration that took root in 2018, when a delegation visited Rice Rivers Center to learn more about his sturgeon restoration research. The following year, he traveled to the U.K. for the James/Thames twin rivers exchange, and the conversations continued.
"I'm astounded how what seemed like a trivial chat at the Rice Rivers Center has grown into," Balazik said. "I never expected things to move in this direction. Seeing folks' faces light up just on the thought of sturgeon returning to local U.K. waters was motivation to help them achieve that goal - and also to appreciate what we have here in Virginia so much more."
Researchers collected environmental DNA samples from the rivers they visited. (Zoological Society of America)Balazik's recent trip came on the heels of a visit to Rice Rivers Center by Hannah McCormick, project officer at ZSL. In December 2023, she joined him on the James River in a search for juvenile sturgeon, and in Balazik's return visit, he helped the U.K. research team in three areas: assessing riverine habitats, determining steps for habitat improvements and evaluating fish migration and the barriers faced.
The River Severn was the primary focus, where the group spent three days covering more than 40 kilometers in a search for sturgeon and suitable habitats. Environmental DNA samples were collected and are being analyzed by research partners at the University of Hull.
"We can't prove sturgeon weren't there, but getting positive samples, called hits, can prove they were in the area the water sample was taken," Balazik said.
In addition to his expertise, he brought technology from Rice Rivers Center. The 4125i EdgeTech Side Scan Sonar System sends and receives pulses to make a substrate map of a river bed as seen from the top looking down, showing everything including intricate channel cuts, substrate type - and even large fish like sturgeon. The finished view is as if the water were removed from the river, akin to how a physician uses an MRI as a diagnostic tool.
The data will help determine if the Severn presents an environment for repopulation efforts and locate the most promising areas of the river for sturgeon to spawn. The group gained support from government agencies including the Environment Agency and Natural Resources Wales, the University of Hull and other members of the U.K. Sturgeon Alliance, including the Severn Rivers Trust, Institute of Fisheries Management and Blue Marine Foundation.
The research team spent an additional day on the River Wye, which flows throughout England and Wales and has an ecosystem that is very different from the Severn. There are no barriers or manmade weirs in the Wye - weirs aid navigation and offer flood protection to villages but can impede fish migration. This higher water quality could provide an ideal spot for reintroducing the fish.
"We were excited to get on the Wye, because it is nothing but rocks, ripples and fast water, a spawning sturgeon paradise," Balazik said. "Sturgeons need access to fresh water with clean, hard substrate, like rock, to spawn. The Wye isn't an industrial river, which means flow dynamics are more natural for the fish that evolved to live and spawn there."
While the river was perfect for sturgeon, the Wye proved to be less than ideal to navigate above the water. The shallowness of the rocky riverbed and narrow waterway forced the research team to tie two canoes together to steady themselves during data collection.
The rivers and weirs weren't the only obstacles the team faced. The technology brought from VCU was powered and configured on 120 volts, where the U.K. operates on 230 volts. The morning of the second day, Amazon delivered a number of converters to the team's location on the Severn.
In enlisting VCU researcher Matt Balazik's expertise, the ZSL was building on a collaboration that took root in 2018, when a delegation visited Rice Rivers Center to learn more about his sturgeon restoration research.(Zoological Society of America)"We learned a lot about what we needed to run the equipment and the nuances of working on different types of rivers," Balazik said. "We covered a lot of ground very quickly while we were there, and now we have the lessons learned that will increase our reach and streamline the way we do our research next time."
Some of the ground Balazik covered was off the rivers. Word of his visit reached the Environment Agency, the U.K. version of the Environmental Protection Agency, and he provided an impromptu demonstration on data collected from the side scanner from its use at Rice Rivers Center.
Talks are underway about Balazik possibly returning to help the EA and ZSL conduct further research. Now he is back at Rice Rivers Center for what he calls "scramble time" - the review of data he collected on his June trip. He hopes to share a rough version of his report in late August, with a finished product to come in the late fall or early winter.
"This is the amazing story of how an ancient and iconic fish was nearly lost on two continents and is now reconnecting Virginia and the U.K. biologists across more than 400 years of history and nearly 4,000 miles of ocean," said Greg Garman, Ph.D., director of the Rice Rivers Center. "The center is pleased to contribute to the eventual recovery of Atlantic Sturgeon wherever they once swam."
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