First prehistoric spawning in 50 years in Georgia

Scientists and students conducting a census of Georgia lake sturgeon discovered three females with developed eggs, indicating that the armored “living fossils” may be reproducing in Georgia for the first fish in fifty years.

Martin J. Hamel, an associate professor at the University of Georgia Warnell School of Forestry and Natural Resources, said in a recent press release, “It’s great because it confirms that they are getting mature and attempting to reproduce.”

According to experts, fossils reveal that the spade-nosed fish with a vacuum hose instead of jaws has lived for more than 136 million years.

According to the U.S. Fish and Wildlife Service, lake sturgeon inhabit 18 states and five Canadian provinces in the St. Lawrence, Hudson Bay, Great Lakes, and Mississippi River basins. They are one of nine sturgeon species and subspecies found in the United States.

Pollution, habitat damage, and harvesting for meat and caviar have drastically reduced their population, prompting the U.S. Fish and Wildlife Service to propose federal protection for the species.

According to the Minnesota Department of Natural Resources’ website, the bone-plated bodies of sturgeons caused so much damage to fishing nets in the 19th century that commercial fishermen discarded a huge number of them on river and lake banks.

Dams, which prevent large fish from traveling from lakes to rivers where they breed, have led to a decrease in their population. The current population of lake sturgeon is less than 1% of historical levels.

Sturgeon has benefited from state regulations like as fishing limitations and stocking programs, some of which are administered by Native American tribes.

In the 1970s, lake sturgeon disappeared from the Coosa River basin in northwest Georgia, the only site in Georgia where they had been found.

Hamel said that the state Department of Natural Resources reintroduced lake sturgeon 20 years ago, when the Clean Water Act purified the river.

Lake Sturgeon Georgia
Matt Phillips, a graduate research assistant at the University of Georgia, supplied this image of a young lake sturgeon on the Coosa River in Rome, Georgia, on June 16, 2022.

According to Michigan Sea Grant, it takes females 20 to 25 years to develop and produce the black, iridescent eggs that humans like eating. Nobody knew whether Georgia’s sturgeon were living long enough to spawn until this year, when such eggs were discovered in females implanted with radio telemetry tags to follow their movements.

“Because lake sturgeon take a long time to grow and then spawn sporadically – every two to three years – we want a healthy population of various sizes and age groups,” Hamel said.

The current population estimate is the greatest since 2002, when Georgia first gathered fish eggs from Wisconsin, hatched them, and released them into the Coosa. Since then, state natural resources personnel have collaborated with Wisconsin colleagues practically every year.

Hamel said, “It’s a significant commitment since you don’t even know whether the stocked fish will survive, much less thrive and breed.”

Since 2002, over 330,000 fish, the majority being approximately 6 inches in length, have been released, according to an email sent by Hamel to The Associated Press.

“While this may seem like a large number of sturgeon, the survival rate of fish discharged at this size is probably between 1 and 10 percent,” he said.

Students are capturing as many lake sturgeon as possible in order to determine population size, survival, and growth rates. The undertaking began in the spring. Hamel said that it would continue through this summer and next spring and summer, concluding in winter 2023.

Radio telemetry tags will provide a clearer picture of where sturgeon inhabit the river basin.

Hamel wrote: “We have implanted telemetry tags in 28 fish thus far and expect to implant 12 more in the next months.”

Hundreds of fish have been implanted with small PIT tags, similar to those used to identify pets, by scientists during the last two decades. The tags allow researchers to determine when and where fish were previously captured.

Hamel said that 15% to 20% of the fish being captured had PIT tags, and each untagged fish receives one.

Five adults and five kids will be tagged with a device that detects depth and temperature every ten seconds, he added.

According to data from the first three years of restocking, youngsters were surviving.

“There have been many uncertainties about long-term survival, growth rates, and when these fish would become sexually mature – and we’re on the cusp of establishing whether or not these fish will successfully breed,” Hamel said.

The oldest lake sturgeon recorded by the Fish and Wildlife Service was 152 years old. The government reports that the fish may reach 9 feet in length and 310 pounds in weight.

The group from Georgia’s greatest catch to date measured 52 inches in length and weighted 24 pounds.

Hamel noted, “This is the biggest fish ever reported in the Coosa River.”

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