The US Fish and Wildlife Service was taken aback last week when they discovered a massive sturgeon fish in the Detroit River that was thought to be over 100 years old.

Catching The Sturgeon

A three-person crew captured the 240-pound lake sturgeon on April 22 near Grosse Ile, just south of Detroit. The massive fish, which measured nearly 7 feet long, was characterized by the agency as a "true-life river giant."

On a long line extending deep into the Detroit River, the massive aquatic species was captured using frozen round goby, tiny, soft-bodied fish that act as tasty snacks for sturgeon, as bait. Using a net, the fishing biologists took about six minutes to get the big fish into their port.

"I could feel the fish thudding against the line. "It only got bigger and bigger as it got closer," Jason Fischer, who was with fellow biologists Paige Wigren and Jennifer Johnson, said.

After weighing and measuring the trout, the department said it was soon released back into the river.

Wigren remembered thinking at the time that catching the sturgeon would make for a "very interesting fish tale."

"She was exhausted and didn't put up much of a fight," Wigren said. "Imagine all the fish has seen and witnessed."

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Lake Sturgeon

Lake sturgeon, an endangered species in Michigan and 18 other states, are freshwater fish that live in the bottoms of streams, river basins, and drainages such as the Hudson Bay, the Great Lakes, and the Mississippi River according to the Fish and Wildlife Service. The extinction of the fish has been linked to overfishing and habitat destruction due to dam building.

Though lake sturgeons were once plentiful in the rivers of Michigan, the St. Clair-Detroit River system now has only about 28,000 specimens. To save sturgeons from becoming extinct, commercial fishing is banned, and amateur fishermen are permitted to keep only one specimen a year, provided it does not reach a certain size and is caught in one of the specified harvesting areas.

Sturgeon Status in Detroit

Anglers are allowed to hold one sturgeon a year, but only if it is above a certain size and captured in a limited number of state waters. In the Detroit River, all sturgeon trapped must be released.

Although a male sturgeon's average lifespan is 55 years and a female is 70 to 100 years, the massive Detroit River sturgeon, a female, is thought to have lived much longer Natural Resources.

100-Year-Old Sturgeon

The Fish and Wildlife Service said, "Based on its girth and age, it is believed to be a female and that she has been cruising our waters for over 100 years."

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