The Coupeville-Port Townsend ferry route will remain on a one-boat schedule through June 6 because COVID-19 has resulted in staffing shortages, Washington State Ferries reported Tuesday.

Two-boat service was supposed to resume for the season on May 9.

All reservations made for the second boat through June 6 were canceled, and the ferry system said customers should double-check their itineraries to see if they are affected. They will need to make new reservations.

A combination of crew members who had contracted or been exposed to the virus, along with those who were off the clock to get the vaccine, resulted in a staffing shortage that will prevent the route from adding a second boat as it enters peak season.

“We’re just short-staffed at the moment unfortunately,” said Washington State Ferries spokesperson Ian Sterling.

Of 600 staff per day needed to operate the boats, the ferry system is averaging about 70 people per day that are out for any given reason, Sterling said.

Absences are concentrated in the engine rooms and fleet personnel.

“We might get away with fewer ticket takers, but when it comes to Coast Guard-mandated positions, we have to have full crews,” Sterling said.

Other routes have also faced cancellations for individual sailings, he added.

“It’s not just a Port Townsend issue, it’s system-wide,” Sterling said, “but the pain is going to be felt on this route a little longer.”

He said people may not realize the amount of training ferry workers need to be on board, which includes firefighting and first aid.

“They’re not just directing the cars around,” he said. “These are highly trained merchant marines that are regulated by the Coast Guard.”

More staff are in training right now to prepare for the summer season, but it has been slower than officials hoped due to social distancing guidelines.

The ferry system should have a better idea in the next few weeks if the second boat will be delayed beyond June 6, Sterling said.