Independent truck drivers gather to delay the entry of trucks at a container terminal at the Port of Oakland, during a protest against California's law known as AB5, in Oakland, California, July 18, 2022.
Independent truck drivers gather to delay the entry of trucks at a container terminal at the Port of Oakland, during a protest against California's law known as AB5, in Oakland, California, July 18, 2022. Reuters / CARLOS BARRIA

Truckers protesting California's new "gig worker" law blockaded the state's third-busiest seaport for a second day on Thursday, stalling agricultural exports and threatening to worsen U.S. supply chain backups.

The largest marine terminal at the Port of Oakland was closed on Thursday, while the three other marine terminals on the property had some on-ship labor underway, port spokesman Robert Bernardo said.

Independent truck drivers are blocking terminal gates and preventing truckers from entering the port in protest of California's new labor law formally known as AB5. The law would make it more expensive for big rig drivers to remain independent contractors and is pushing the trucking industry to hire those workers as employees.

The Port of Oakland is a key hub for California's $20 billion-plus agriculture exports, which include almonds, rice and wine. The eighth-busiest U.S. container seaport was already working to clear a pandemic-fueled cargo backup before the trucker protests began.