A federal agency says it made a mistake with a key piece of data it gave to New Jersey U.S. Sen. Cory Booker as he was building a case to shut down America's shark fin trade.

The Democrat has cited more than 500 incidents involving complaints of shark finning in the U.S. as cause to support shutting the trade down. But the number is actually 85.

Booker reached out to the National Oceanic and Atmospheric Administration months ago to find out how often it investigates allegations of shark finning, an illegal practice in which a shark's fins are removed and the shark is discarded into the water.

The NOAA said Thursday a worker's error involving a new case management system caused the mistake.

Booker's office hasn't returned a call seeking comment.