The US Border Patrol seized the shipment shortly thereafter.
The mayor of the Florida city of Tampa came across a big catch during a recent fishing expedition: about 70 pounds (31.7 kilograms) of cocaine, valued at around $1.1 million, US media reported.
Jane Castor was enjoying a vacation day off Marathon, in the Florida Keys, on July 23 when a family member spotted something in the warm Atlantic waters.
At first she thought it was "shade as opposed to something shady" -- perhaps small fish clustered under some debris in the ocean, she told Fox 13 news.
But the "closer we got, I was like, 'oh, that would be a bale of cocaine'," she said.
Ms Castor said she had no doubt what she was seeing: her more than three decades on the Tampa police force, including six years as its chief, allowed her to recognize the drug stash with absolute certainty.
The family loaded the microwave-sized package onto their boat. Tightly packed bundles were visible under layers of plastic film.
Ms Castor saved the location of the find in her watch and called the Monroe County Sheriff's Office.
The US Border Patrol seized the shipment shortly thereafter.
On July 24, officials announced the find on social media, attributing it to "a recreational boater" and including a photograph of the stash: 25 bricks of cocaine, each stamped with a purple butterfly.
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