Thanks to Mlive for this:
A photo of a monster-sized prehistoric fish laid out on a boat deck next to a much smaller person is evidence of one of the largest lake sturgeon ever recorded in the United States.
The fish was caught last week by the Detroit River native species crew of the Alpena Fish and Wildlife Conservation Office, according to a news release via Facebook.
The female weighed in at 240 pounds and measured 6 feet and 10 inches long. She was quickly processed and returned to the river – but not before snapping the eye-catching photo.
The conservation office describes the sturgeon as a “real-life river monster” and a “once in a lifetime catch.”
Officials believe the fish has been roaming the Detroit River and surrounding waters for more than 100 years, hatching in the Detroit River around 1920.
A once in a lifetime catch for our Detroit River native species crew last week! This real life river monster was tipping the scales at 240 lbs, measuring 6’10” long, and a girth of nearly 4′. Caught in the Detroit River, this fish is one of the largest lake sturgeon ever recorded in the U.S.
Based on its girth and size, it is assumed to be a female and that she has been roaming our waters over 100 years. So, she likely hatched in the Detroit River around 1920 when Detroit became the 4th largest city in America 
She was quickly released back into the river after being processed!
Wow!