Wild Fish In Gene Banks, Hatchery Fish In Elwha — Why The Two-Headed Strategy?
Washington state has banned hatchery-raised steelhead from three tributaries of the Upper Columbia River basin. The aim of these so-called "gene banks" is to maintain strongholds for wild fish, and the state plans to designate additional gene banks in the future.
So why were the state and federal governments back in court this week, defending the decision to place a new hatchery on the Elwha River as part of the dam removal process?
NOAA Official: Hatchery Fish Not Always Bad
Officials say more than 20 years of research has proven that hatchery fish have lower survival rates than wild ones. And when they cross-breed, wild fish stocks are diminished. This is true for salmon and steelhead, and management plans call for an expanded network of gene banks all over the state over the next several years.
So why did the feds insist on keeping hatchery fish in the Elwha River system as part of the dam removal deal?
“They are a tool, and they have both benefits and risks,” said Rob Jones with the National Oceanic and Atmospheric Administration Fisheries Services.
Jones says hatcheries aren’t always good or always bad; it’s a matter of finding appropriate use.
“The trick is finding where that tool works the best, and making sure that the benefits outweigh the risks,” he said.
Why Hatchery Fish Were Added To The Elwha River
In the case of the Elwha River, Jones says the use of the hatchery was meant to preserve severely endangered fish stocks that serve an important function, even if their offspring don’t live as long.
The 100-year-old dams on the Elwha restricted habitat from an entire river basin to just a few miles. And very recently, the salmon runs there had diminished to less than a thousand fish returning in some years.
All things considered, the risk was too great not to have hatchery fish as a backup plan, wildlife officials say, because 100 years’ worth of accumulated sediment, which is the raw material salmon need to lay their eggs, has been unleashed and is now flowing down the river.
“Which is a good thing for fish in the long run, and that’s the biggest reason why we’re pursuing this. But in the short term, it’s really difficult,” Jones said.
The sediment is moving faster than initially predicted and can easily knock out the nests (called “redds”) where spawning fish take harbor and plant their roe.
Enviro Groups' Suit: Purist Approach Is Best
But the decision to plant non-native, hatchery-raised fish in the Elwha River has landed the feds, the state’s Department of Fish and Wildlife and the Lower Elwha-Klallam Tribe in court.
The plaintiffs, four environmental groups led by the Wild Fish Conservancy, say the ecosystem would be better off without hatchery fish. Their attorney, Brian Knutsen, says the huge flows of sediments coming downriver do not threaten the wild fish.
“Our salmonid experts believe that there’s almost no risk of losing the local Elwha genetic stocks from the sediment increase associated with dam removal," he said, "and that the fish would be better adapted if we were not introducing hatchery fish in a manner that allows the hatchery fish to interact with the wild populations."
On Wednesday, U.S. District Judge Benjamin Settle heard oral arguments in the case, and asked the defendants to file a brief on genetic safety. The plaintiffs will have a chance to respond to the brief before the judge makes a ruling.
State Of The Elwha
The dams on the Elwha River were not producing enough electricity to justify their relicensing, so they are being taken out. The removal process will be completed by this fall.
So far, not only the sediments, but also the size of the returning fish runs are bigger than expected.