Milestone in sturgeon science: 2,000th fish tagged
Dr. Matt Balazik, who researches Atlantic sturgeon at Virginia Commonwealth University’s Rice Rivers Center, caught, tagged and released his 2,000and sturgeon last week. This landmark fish, tagged near Westover Plantation a few miles downriver from the Rice Rivers Center, was a 24-inch juvenile that represents years of research. Genetic testing indicated he was born as part of the 2018 James River fall sturgeon cohort. Each of these 2,000 fish carry a unique Passive Integrated Transponder (PIT) tag that registers on a receiver if captured.
In addition to PIT beacons, 200 of the sturgeons also carry radio tracking beacons with unique frequencies. Thanks to the Atlantic Coastal Telemetry (ACT) network of receivers, Balazik knows at all times where most of these radiotagged sturgeons are and how far they have travelled.
Balazik recently looked at last year’s data to make a discovery that surprised even him. A sturgeon tagged in the 2021 spawning run traveled a breathtaking 525 miles.
“I knew they had traveled at least 100 kilometers to get to the spawning habitat, but I hadn’t realized how far some of them had traveled back and forth,” he said. declared. Of the 25 fish he checked, the average was 570 kilometers (354 miles).
The patterns were interesting. Some fall season male fish swam to their main spawning grounds early in the season between Osborne Landing and Curles Neck, mated with mature females, then moved downstream back to Burwell’s Bay, but smelled another mature female swimming upstream late in the season and followed her, doubling their travel distance. Radio beacons and the ACT network offer an extraordinary look into the lives of these mysterious ancient fish.
He has just finished tagging spring mature fish, as they will complete their activities around May 22. Balazik will work on his data and then over the summer will start looking for fish that are coming in for James’ biggest fall run, which will last from late August through early/mid-October. In the fall, lower seasonal rainfall means salt water reaches higher up the James than in the spring, so big fish have to swim further upstream to find the fresh water they need to spawn with. hit.
Balazik’s discovery of the 525-mile endurance athlete sturgeon inspired a fun fitness challenge for the Rice Rivers Center. When Balazik was biking along the Virginia Capital Trail near Jamestown in March, he had the idea of trying to cycle the distances covered by sturgeons during their spawning grounds.
In addition to covering the distance himself, Balazik and the Rice Rivers Center challenge endurance athletes to bike, run, walk, swim, paddle or row these distances. The inaugural James River Spring Sturgeon Challenge encourages participants to set a goal similar to the voyages of the James River Sturgeon, with a May 22 race end date deadline. The minimum would be a day trip the shortest distance of a spring sturgeon. moved during the season: 212 kilometers (about 132 miles). The maximum corresponds to the longest, 841 kilometers.
“Let your imagination run wild,” Balazik said. “Feel free to run, walk or cycle anywhere in the world and share your goals and experiences.”
If you like the idea, but the May 22 deadline comes too early for planning, don’t be disappointed. “We’ll take on the challenge again in the fall,” Balazik said. “I already have the numbers and it’s going to be even further than the spring challenge.” Stay tuned bay bulletin for more information on Atlantic Sturgeon in the Chesapeake and the VCU Rice Rivers Center Fall James River Sturgeon Challenge.
-John Page Williams