GOLD HILL — Ninety spring chinook salmon slid down a metal tube Wednesday at the Gold Hill boat ramp and dropped into the Rogue River.
Two hours later, another 90 springers did the same at Dodge Bridge about 24 miles upstream.
Together they make up the latest experiment to get more of these Rogue gems into barbecues and smokers instead of hatchery ponds and spawning gravels.
Oregon Department of Fish and Wildlife biologists are tinkering with the state's popular spring chinook recycling program by splitting the releases between Gold Hill and Eagle Point in an attempt to spread the wealth of excess chinook instead of dumping them all at TouVelle as they have in years past.
Along with about 100 spring chinook released at each of those locations Thursday, anglers along 36 miles of the Rogue will have extra chinook to cast for through the popular Fourth of July fishing weekend.
"We want to make sure we have fish in a couple of reaches of the river for anglers, especially the Shady Cove/Trail anglers," says Dan VanDyke, the ODFW's Rogue District fish biologist.
The scheme takes on a new wrinkle in early July when another batch of excess spring chinook will be trucked down to Dodge Bridge near Eagle Point and released to give anglers one last shot at catching and keeping one of the upper Rogue's signature salmon before the season ends there July 31.
"In the ideal world, any hatchery fish would be caught and utilized by anglers," VanDyke says.
Seeing many more spring chinook in the hatchery than on the ends of their lines has been a sore point for upper Rogue anglers often frustrated at how finicky a biter a spring chinook can be.
All Rogue spring chinook are bound for the upper Rogue, and the run remains dominated by hatchery fish returning to Cole Rivers. The hatchery uses about 1,600 returning fish for brood stock, with the rest either killed for American Indians as part of treaty rights, sold to a fish processor, used for stream-enrichment programs or recycled for anglers.
As far back as the mid-1980s, early-run extras have been released at TouVelle, but poor early returns have seen that option disappear through much of the middle part of this decade until last year, when 2,163 springers were recycled, says David Pease, the hatchery's assistant manager.
The recycled fish have a hole punched in their gill plate to denote their status, and they can be kept by anglers as hatchery chinook.
Under the original program devised by ODFW biologists, up to 4,000 spring chinook could be recycled before July 1, Pease says.
Those released after July 1 were thought to pose a greater risk of straying onto native spring chinook spawning grounds.
Last year, VanDyke tweaked the policy by having hatchery technicians release 195 spring chinook July 11 at Dodge Bridge.
Chinook spawning-ground surveys last fall showed these fish didn't stray onto wild fish spawning grounds, prompting another planned release within two weeks.
"We'll try it for a couple years and see what the results are," VanDyke says.
The trick is to keep as many hatchery fish in the upper Rogue as possible for anglers, and recycled chinook could be just the ticket.
An ODFW study in the 1980s showed that recycled fish actually move upstream slower than when they ran the angling gauntlet the first time.
Recycled chinook affixed with radio transmitters migrated an average of .85 kilometers a day. That means fish released at Dodge Bridge on Thursday should remain in the upper Rogue and available to anglers through the season's end July 31.
"We want to make sure anglers, especially those in the Shady Cove and Trail areas, get a crack at these fish," VanDyke says.
Reach reporter Mark Freeman at 541-776-4470, or email firstname.lastname@example.org.