Over 100-year-old fish weighing more than 108 kg caught in Detroit River, later released

“Based on its girth and size, it is assumed to be a female and that she has been roaming our waters over 100 years. She was quickly released back into the river” after being weighed and measured, the Fish and Wildlife Service said.

Now that's a whopper — a very old whopper!

The image shows the huge fish caught in Detroit River and later released. (Facebook/@AlpenaFWCO )

A 240-pound (108.8 kilograms) sturgeon that could be more than 100 years old was caught last week in the Detroit River by the U.S. Fish and Wildlife Service.

The "real life river monster" was nearly 7 feet (2.1 meters) long, the agency said Friday on Facebook, where the photo was shared more than 20,000 times.

“Based on its girth and size, it is assumed to be a female and that she has been roaming our waters over 100 years. She was quickly released back into the river” after being weighed and measured, the Fish and Wildlife Service said.

The typical lifespan is 55 years for a male sturgeon and 70 to 100 years for females, according to the Michigan Department of Natural Resources.

This fish was caught on April 22 near Grosse Ile, south of Detroit, while a three-person crew was conducting an annual sturgeon study. Frozen round goby — “like a stick of butter to sturgeon” — was used as bait, said James Boase, a Field and Wildlife Service biologist.

Lake sturgeon are listed as a threatened species in Michigan. Anglers can keep one a year, but only if the fish is a certain size and is caught in a few state waters. All sturgeon caught in the Detroit River must be released.