A record number of cargo ships off the California coast shows a crack in the supply chain.

Container ships were lined up this week off the coast of Southern California, waiting to deliver cargo at the Port of Los Angeles and the Port of Long Beach. The backup offered another sign of the supply chain woes bedeviling businesses across the globe.

Sixty-one vessels were anchored offshore on Thursday waiting to unload cargo, down from a record 73 on Sunday, said Capt. J. Kipling Louttit, the executive director of the Marine Exchange of Southern California, a nonprofit that works in partnership with the Coast Guard to provide data on maritime commerce.

In addition to the anchored ships, 29 were adrift up to 20 miles offshore, meaning they were so far from the coast that their anchors could not reach the ocean floor. That’s down from a record of 37 set on Monday, Captain Louttit said, but the traffic is not abating.

“We are in our 11th month of managing this record-breaking traffic,” he said. “We’ve never had a problem like this before.”

The delay in getting the container ships to port comes as the easing of pandemic restrictions and an increase in consumer spending have ramped up demand. As a result, manufacturers are struggling to keep pace, and shortages of some products, like semiconductors, have caused slowdowns in production. The problem has been exacerbated by the rise of the Delta variant of the coronavirus, which is causing labor shortages as workers are quarantined.