Massive Sturgeon, A Real-Life 'River Monster,' Caught In Michigan

ALPENA, MI — While the popular Animal Planet show "River Monsters" typically traverses remote waterways in search of the most fearsome freshwater and saltwater killers, a real-life "river monster" was discovered this week right in Detroit's back yard.

The Alpena Fish and Wildlife Conservation Office posted a photo of its historic catch to its Facebook page on Friday. Caught in the Detroit River by the office's native species team, the massive sturgeon weighed in at 240 pounds and measured nearly 7 feet long with a girth of 4 feet.

Alpena is located about four hours north of Detroit.

Based on its size, the female sturgeon is likely more than 100 years old, conservation officials said.

"So, she likely hatched in the Detroit River around 1920 when Detroit became the fourth-largest city in America," the post read.

Officials said they released the sturgeon back into the Detroit River shortly after she was processed.

In other words, if you happen to see a whale-size silhouette while strolling near the river's banks, you'll know why.

Is the sturgeon the largest ever caught in the United States? Not quite.

In 1961, a 680-pound Goliath grouper was caught on the Amelia River in Florida, according to Field & Stream magazine. While it's unclear if the grouper holds the record of the largest caught in the states, it does eclipse the sturgeon's size by nearly three times.

Another sturgeon caught in 1983 in California also tops the largest fish caught in the United States. The 9-foot-6-inch fish was also estimated to be 100 years old.