Tens of thousands of baby salmon made a new home in the Oak Harbor marina last Thursday.

The fish were born in Marblemount Fish Hatchery in Skagit County and were delivered to the marina by the Washington State Department of Fish and Wildlife.

With the help of volunteers, marina staff built two wooden pens that are 15-by-30 feet in diameter. The fish are kept in the pens with a nylon knotless net.

The fish were transported from Marblemount in a large tank on the back of a truck and traveled down several feet of tubing to splash into their new home. Each pen received 15,000 juvenile coho salmon for a grand total of 30,000.

The salmon are about a year old. Their arrival in the marina is their first time in saltwater.

The fish-rearing program originally started in Oak Harbor in 1982 and continued until 2011. In that time, about a million fish were raised and released into the bay, according to Harbormaster Chris Sublet. The program returned last year.

The three goals of the program are to revive fishing in the Oak Harbor area, create outdoor classrooms and learning opportunities for local school children and to support Gov. Jay Inslee’s orca task force mandate. Southern resident killer whales feed primarily on salmon which, along with the orcas, are in decline.

When they first arrive at the marina, the salmon are only a couple of inches long. They will live in the pens at the marina and be fed fish food by staff for a few months until they are released sometime in May. By the time they are released, they can be around a foot in length.

The fish are fed three days a week. Marina Maintenance Attendant Alyce Henry said she does a “slow feed” which means she takes a break when handing out food. This allows both the aggressive eaters and the more passive eaters a chance to chow down.

Henry monitors the fish and has a system for tracking their growth. She checks the salmon every day for any abnormalities or any deceased fish and records any factors that may have contributed to a loss.

“They have a lot of requirements that they’re meeting,” said Sabrina Combs, communications manager for the city of Oak Harbor.

In three years after their release, the salmon that survive will return to the shores of Oak Harbor. They only have about a 10% rate of return. Life can be challenging in the Pacific Ocean, where they will live most of their lives. Predators are immediate concerns for the fish after leaving the marina. When they are first released, marina staff use air horns to ward off seals.

The salmon have been moved to D dock at the marina and the public can assist with the feedings. Visit facebook.com/oakharbormarina for updates and information.

The release of the fish in May will be an event open to the public.

“There is really no way to tell how many survive the release,” Sublet wrote in an email. “However, we do expect approximately 10% (3,000 salmon) to return to the Oak Harbor Bay in about three years.”

A total of 30,000 juvenile salmon were transported to the Oak Harbor marina Thursday.

Harbor Master Chris Sublet sets up tubing.

Jessie Howard (left) was one of several volunteers who helped set up tubing to transport the salmon from the truck to the pens.