LOS ANGELES » Seaports in major West Coast cities that normally are abuzz with the sound of commerce have fallen unusually quiet.

Companies that operate marine terminals didn’t call workers Thursday to unload ships that carry car parts, furniture, clothing, electronics — just about anything made in Asia and destined for U.S. consumers. Containers of U.S. exports won’t get loaded, either.

The partial lockout is the result of an increasingly damaging labor dispute between dockworkers and their employers.

The two sides have been negotiating a new contract, and stalled talks have all but paralyzed 29 ports that handle about one-quarter of U.S. international trade — around $1 trillion worth of cargo annually.

The 15 ships scheduled to arrive Thursday at the ports of Los Angeles and Long Beach, by far the nation’s largest complex, will join a line of about 20 others anchored off the coast, waiting for berths at the docks to clear. There are clusters of ships outside the ports of Oakland, Calif., and Seattle and Tacoma in Washington.

The Southern Cali­for­nia slots weren’t opening Thursday — a holiday for Lincoln’s birthday. The ships occupying them were idle because companies that operate marine terminals did not call dockworkers to operate the towering cranes that hoist containers of cargo on and off ships.

The berths won’t clear Saturday, Sunday or Monday, either. On each of the days, dockworkers would get bonus pay for the weekend or Presidents Day holiday.

Employers refuse to pay extra to longshoremen who have slowed their work rate as a pressure tactic, said Steve Getzug, a spokes­man for the Pacific Maritime Association, which is bargaining on behalf of terminal operators and shipping companies.

Friday is a normal workday and would see normal operations.

Dockworkers deny slowing down and say cargo is moving slowly for reasons they do not control.

Employers could still hire smaller crews that would focus on moving containers already clogging dockside yards onto trucks or trains in an effort to free space amid historically bad levels of congestion. Full crews would still service military and cruise ships, and any cargo ships bound for Hawaii.

Cargo has been moving slowly for months across the troubled West Coast waterfront. Containers that used to take two or three days to hit the highway have been taking a week or more, causing disruptions.

Negotiations resumed Thursday in San Francisco — the first day the two sides have met since Feb. 6. Talks have stalled over how to arbitrate future workplace disputes. Some of the biggest issues, including health care, have been resolved with tentative agreements.

In response to employers’ decision to limit work crews, the union noted that longshoremen also were not hired to load or unload vessels last weekend.

"The union is standing by ready to negotiate, as we have been for the past several days," union President Robert McEllrath said. He suggested the maritime association is "trying to sabotage negotiations."