King County scientists recently celebrated flying fish.

The celebration came March 2 as a plane carrying 12,000 Lake Sammamish kokanee salmon eggs landed at the King County International Airport in South Seattle, marking the end of a long collaborative effort to boost the population of the at-risk species.

Two years ago, county biologists flew thousands of live, juvenile kokanee from Lake Sammamish to an Orcas Island salmon hatchery, where the fish were raised until they spawned eggs.

Those eggs were returned to Seattle last Wednesday, and will be raised at the Issaquah Salmon Hatchery before being released into tributaries along Lake Sammamish around October to support wild populations.

This month’s effort was a collaboration between the county, Snoqualmie Tribe and Long Live the Kings, a nonprofit that operates a salmon hatchery on Orcas Island.

That hatchery not only had the cold water necessary to house the fish, but the facility protected the fish from potentially hazardous conditions in the Lake Sammamish — including high water temperatures, low oxygen levels, pathogens and nonnative predators.

“I was on Orcas Island to see the arrival of the fish and that was a pretty momentous occasion,” said Lucas Hall, an associate director of government relations with Long Live the Kings. “It’s quite the culmination of a lot of work.”

The plane ride is one of several emergency efforts from the Kokanee Work Group, a collaboration between governments, nonprofits and the Snoqualmie Tribe, which have been working to save the genetically unique freshwater sockeye that call Lake Sammamish and its adjacent creeks home.

Kokanee, once abundant in Lake Sammamish, have recently been trending toward mass extinction. About 18,000 Kokanee returned to spawn along streams in Lake Sammamish in 2012, but by 2017, fewer than 20 fish returned.

Based on recommendations from the work group, King County Executive Dow Constantine announced plans that the county would sponsor efforts to protect the fish in 2018. Constantine called the March 2 plane landing a cause for optimism during a time with a lot to worry about.

“Our job is to steward this land and this place,” Constantine said at the landing. “Our ability to help [kokanee] survive and bounce back is something we want to be doing a lot more with a changing global climate.”

Since 2017, the work group has diversified its recovery strategy, trying a host of efforts to better understand what works best, with the ultimate goal of having wild fish eventually outpace hatchery fish. This includes remote stream incubators, culvert replacements, a one-of-a-kind cryopreservation effort and others.

“It’s been a struggle,” said Bill Sweet, a Snoqualmie Tribal Councilmember. “We’re just trying to find out what works best. Once we find that, we can keep going.”

Although the “little red fish” aren’t out of the woods yet, there are some signs that efforts by the work group are paying off. Perry Falcone, a restoration recovery program manager with the work group, said 2,071 adult kokanee returned to spawn this past year. That’s more than the last five years combined, he said.

Although those returns are high, the work group is unsure how many of those returners are natural fish, and they won’t know if hatchery efforts are working until they recover fish carcasses and extract the ear bone, a marking used to identify hatchery fish.

Falcone said they’ll have a more clear understanding over the next few months, after more scientific data is gathered. This will give the work group a better idea of which strategies are most effective and how to proceed.

Sweet called this year’s return numbers a blessing. The kokanee are an important part of the Snoqualmie Tribe’s history, providing a critical year-round food source when other options were less abundant — and allowed them to stay on their ancestral lands.

“Our people have been fighting so long, just like the kokanee in the lake,” said Snoqualmie Deputy Secretary and Councilmember Christopher Castleberry. “[The returns] It’s giving me hope and I think that’s worth its weight in everything.”