136-million-year-old ‘living fossil’ fish may spawn in Georgia for the first time in 50 years

By William On Aug 17, 2022

A prehistoric fish that’s been around for 136 million years may once again spawn in Georgia after being wiped out in the 1970s.

The researchers were in the process of tagging and tracking sturgeon in the river system, which is part of an effort to better understand the population since they were reintroduced by the Georgia Department of Natural Resources (DNR) in 2002.

Scientists and students who were taking a census of lake sturgeon in Georgia earlier this year discovered three females with mature eggs, which indicates that these unique ‘living fossils’ might be reproducing in the state for the first time in a half century. Research technician Hunter Rider of Opelika, Ala., holds a lake sturgeon (above) with its vacuum-hose-like mouth extended on the Coosa River

‘We found three females that had black eggs—mature eggs that are ready to be fertilized,’ said Hamel. ‘This was the first time anybody has found a sexually mature female since the reintroduction program began.’

It can take up to 25 years for female lake sturgeon to reach sexual maturity – something that can be observed when they develop black eggs that are also coveted as caviar.

Fossil records indicate that the spade-nosed fish with a bottom-mounted vacuum hose instead of jaws has existed for more than 136 million years, according to scientists.

‘Because lake sturgeon take a long time to mature and then reproduce intermittently — every two to three years — we really need a robust population of varying size and age classes,’ Hamel explained.

‘It’s exciting because it’s confirmation that they are becoming mature and trying to spawn,’ Martin J. Hamel, an associate professor at the University of Georgia Warnell School of Forestry and Natural Resources, said in a statement. Pictured above: A lake sturgeon with its vacuum-hose-like mouth extended on the Coosa River on July 14, 2022

Poor water quality and over-harvesting – of their prized eggs and the fish itself – led sturgeon to disappear from the region in the 1970s. Pictured above: Juvenile lake sturgeon on the Coosa River on June 16, 2022 in Rome, Georgia

Lake sturgeon are native to the Peach State’s Coosa River system and for many generations that area was the only place in the state where the prehistoric fish could be found.

However, pollution, habitat destruction and over-harvesting – of their prized eggs and the fish itself – led sturgeon to disappear from the region in the 1970s. In addition, dams that prevent the fish from migrating from the lakes and rivers where they spawn have also reduced their numbers.

About 30 years later, Georgia’s DNR began a project to reintroduce the fish into the Coosa River.

‘The Clean Water Act really did improve the overall habitat and river quality,’ said Hamel. ‘So, the habitat got better and with a ban on harvesting lake sturgeon, DNR considered trying to reintroduce the population.’

Beginning in 2002, DNR officials worked with wildlife authorities in Wisconsin, where there’s a lake sturgeon population similar to Georgia’s, to bring eggs back to Georgia – where they were incubated, hatched and released into the Coosa River. They’ve repeated this process nearly every year since.

‘It’s a big investment because you don’t even know if the stocked fish are going to survive, let alone grow up and reproduce,’ Hamel said.

About 330,000 fish, most about 6 inches long, have been released since 2002, Hamel said in an email to the Associated Press. ‘While that seems like a lot of sturgeon, the survival rate of fish that are released at that size is likely between 1-10%,’ he wrote.

The oldest lake sturgeon on record was 152 years old, according to the Fish and Wildlife Service. The agency says the fish can reach up to 9 feet long and 310 pounds.

The largest caught so far by the Georgia group was 52 inches long and weighed 24 pounds.

‘This is the largest fish that anyone has documented on the Coosa River,’ Hamel told the Associated Press via email.

One of nine sturgeon species and subspecies found in the U.S., lake sturgeon live in 18 states and five Canadian provinces in the St. Lawrence, Hudson Bay, Great Lakes and Mississippi River watersheds, according to the U.S. Fish and Wildlife Service.