Editor’s Note: The following article was published last month by WDFW.
The spring Chinook salmon hatchery program on the Cowlitz River does double duty: not only does it provide angling opportunity by mitigating the loss of natural salmon production caused by dams in the watershed, but it also helps establish the reintroduction of naturally produced populations above those dams.
To accomplish these goals, the program aims to collect 1,310 adult hatchery fish every year, which in turn can produce just over 1.7 million spring Chinook smolts. Typically, all of these hatchery-raised smolts have their adipose fins clipped at the hatchery before release, to identify them as hatchery fish and allow them to be harvested by anglers when the fish return to the river as adults.
But anglers have been catching more unclipped smolts in spring of 2022 than in past years. And there’s a very good reason for it.
Unfortunately, in 2020, very low marine survival resulted in adult returns well below the 1,310-fish target. By June 7 of that year, only 186 adults had been collected at the hatchery, and only 83 were hatchery-origin fish that could be used in the hatchery program. Historical run timing indicated the run should have been almost 50 percent complete by that date. Due to concerns over the low returns forecasted preseason, fishery managers closed the recreational fishery and considered additional steps to maximize broodstock collection.
As a result of the dire situation, the Washington Department of Fish and Wildlife (WDFW) convened emergency meetings with partners in the basin, including Tacoma Power, NOAA Fisheries and other members of the Cowlitz Fishery Technical Committee (FTC) to establish a plan to address the extreme broodstock shortfall.
The group determined that it was highly unlikely the broodstock collection target would be met, jeopardizing future angling opportunities and reintroduction efforts. The group decided to take action to address these threats, including:
• Ensuring future angling: To ensure fishing could continue in 2023–2025, when the offspring of the 2020 brood will return as adults, Kalama-origin spring Chinook juveniles were transferred to the Cowlitz for rearing and release on a one-time basis. 301,800 of these Kalama-origin smolts were released in March of 2022. Fishery managers viewed Kalama as an acceptable surrogate stock because it is adjacent to the Cowlitz, and spring Chinook from the two basins would be genetically similar and have naturally intermingled in the wild.
• Distinguishing the populations: To ensure that Kalama-origin smolts could be differentiated from Cowlitz-origin smolts when they returned, the Kalama-origin smolts were marked by clipping both their adipose and ventral fins, which will also allow them to be harvested as adults.
• Rebuilding the Cowlitz population: To allow the Cowlitz-origin run to rebuild and ensure the sustainability of future fishing opportunity and reintroduction efforts, the Cowlitz-origin smolts — for the 2020 brood year only — did not have their adipose fins clipped. Instead, 100 percent of the Cowlitz-origin smolts were implanted with a Coded Wire Tag in their snout. A coded wire tag contains a unique code that can identify a group of fish that were released at the same place and time.
In early April 2022, the Cowlitz Salmon Hatchery released 610,000 of these unclipped smolts.
By not adipose-clipping these smolts, they will not be available for harvest as adults, maximizing the chance that the Cowlitz spring Chinook program could meet its broodstock collection target in the future.
As a result, anglers may encounter — and may have already encountered — unclipped hatchery-origin spring Chinook smolts in the Cowlitz in 2022, as well as jacks in 2023 and adults in 2024 and 2025. These fish are externally indistinguishable from natural-origin spring Chinook, which are also present in the Cowlitz.
Fishery managers will still be able to tell the hatchery-origin fish from the natural-origin fish by scanning fish for coded wire tags at the hatchery. All returning adults exceeding what’s needed for hatchery goals will be transported to the upper basin for reintroduction purposes.
Fish with an intact adipose fin are not open to retention, and if caught, should be released unharmed immediately. Your help in releasing these fish will contribute to ensuring sustainable harvest opportunities and reintroduction efforts in the future. Clipped Kalama-origin fish will still be available for harvest in coming years when the fishery is open for Chinook retention. There will also be clipped Cowlitz fish returning from other brood years available for harvest in 2023–25, since spring Chinook can return as 3-year-old jacks, or as 4- and 5-year-old adults.
Like in years prior to the 2020 brood year and 2022 smolt release year, 100 percent of future hatchery spring Chinook releases in the Cowlitz are expected to have their adipose fins clipped to allow retention of returning adults.