Menlo Park has more registered commercial drones than any other U.S. city, according to a database released by the Federal Aviation Administration (FAA) on May 18, and initially reported by MarketWatch.

At 176 registered commercial drones, Menlo Park's number is higher than the 138 registered at second-ranking Maxwell Air Force Base in Alabama, or in Los Angeles, where 83 commercial drone are registered.

The FAA database did not release the names of the drones' owners or name the business they are affiliated with. Menlo Park is home to drone delivery startup Matternet.

As for users who fly drones as a hobby, Menlo Park reported 168 registered drone owners. Houston, Texas, had the most registered hobby-related drones users at 3,061, according to MarketWatch.

Ian Gregor, a spokesperson for the FAA, said commercial drone owners must register each aircraft individually, but hobbyists can register multiple aircraft with just one registration number. In Menlo Park, that means there could be more than 168 drones being flown for hobby-related use, as each owner could possess multiple drones. Also, some owners may not register them.

The database is the result of an unmanned aircraft registration program, begun in December 2015, that requires anyone who owns a drone weighing between 0.55 and 55 pounds to register it before flying it outdoors.

So far, Mr. Gregor said, there have been about 450,000 hobbyists who have registered their drones.

"Nobody has an exact count of all the drones that have been purchased," he wrote in an email to the Almanac.

Go to the FAA website to register a drone.