All hatchery spring chinook salmon have fin-clips

There have been rumors surfacing again as to whether the folks at Cole Rivers Hatchery actually fin-clip all the hatchery fish they release into the Rogue River. Specifically, it is rumored that a large number of hatchery fish are not clipped and thus treated as wild fish that fishermen must release. Can you get a straight answer on whether this is true?

— Matt, Eagle Point

Well, Matt, rumors of alleged malfeasance at Cole Rivers Hatchery have been circulating along the upper Rogue pretty much ever since the hatchery went online 43 years ago. We at Since You Asked have even checked on several of them, and have yet to find one penciling out.

The rumor that not all of the spring chinook have a clipped adipose fin falls into that category.

The Oregon Department of Fish and Wildlife began clipping the little fleshy adipose fin on the backs of hatchery spring chinook smolts in 1998 to make them identifiable from wild spring chinook, says Dan VanDyke, ODFW's Rogue District fish biologist.

At the time, a small number of research fish that had coded-wire tags embedded in their snouts were not fin-clipped, VanDyke says.

And that likely is the kernel of truth that led to the rumor, Matt.

That research program ended in 2005, and since then, all of the roughly 1.6 million to 1.7 million spring chinook reared at Cole Rivers for release into the Rogue have had clipped adipose fins, VanDyke says.

The Rogue hatchery chinook set for release this year are currently getting their fins clipped at Cole Rivers.

Hatchery Manager David Pease says ODFW's two fin-clipping trailers arrived there last week and expect to be done clipping by the end of this week.

The clipping system is plenty interesting on its own. The small fish are held individually and clipped while an image of the clipped fish is taken, Pease say. If the clip is right, the fish is released, he says. If not, it rejects it and one of two trained employees hand-clip the fish, Pease says.

"It's pretty cool," Pease says. "You can see it all happening.

The Rogue's adult spring chinook run is just starting in the upper Rogue, and anglers riverwide must release all wild springers they catch, but they can keep up to two fin-clipped hatchery fish a day.

— Send questions to “Since You Asked,” Mail Tribune Newsroom, P.O. Box 1108, Medford, OR 97501; by fax to 541-776-4376; or by email to We’re sorry, but the volume of questions received prevents us from answering all of them.

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