‘Strange-looking’ fish tagged in Alabama river weighs 150 pounds, researchers say

As if 119 pounds wasn’t big enough, when researchers found a fish that had been tagged over a decade ago in an Alabama river, they found it had gained 30 pounds.

During the 12 years since its first measurement, a female gulf sturgeon tagged by researchers in 2010 had grown to 150 pounds — and it’s still not the biggest of its species, Steve Rider, a biologist with the Alabama Wildlife and Freshwater Fisheries Division, told McClatchy News.

Biologists once caught one that was 8 feet long and weighed 200 pounds, he said. But they can reach lengths of up to 14 feet, according to the Alabama Department of Conservation and Natural Resources.

The fish species, which is considered threatened, has been around for 180 million to 220 million years, Rider said. This type of prehistoric existence is rare to find in animal species, especially in the U.S., he said.

The gulf sturgeon caught recently in the Choctawhatchee River, a 100-mile river that flows through southeastern Alabama and the Florida Panhandle, is special in part because she appears to be spawning, something researchers previously thought the sturgeon only did in the springtime.

To study the fish, researchers plant acoustic tags, which resemble “big chapstick tubes,” inside the fishes’ stomachs, Rider said. The tags then ping off receivers in the water and help scientists track the animals’ movements.

This prehistoric species, Rider said, is particularly important to study because they are sensitive to environmental changes and are good indicators of the health of the habitat around them. As the earth warms due to climate change, researchers will be keeping a close eye on these massive, “strange-looking” fish, he said.

“If you look at their skin, they have modified scales like armor over their entire body,” he said. “... very unique, different patterns (like) nothing I’ve seen in any other fish.”

This story was originally published August 31, 2022 at 6:03 PM.