What about the effects of the hatcheries?

Hatcheries are used to significantly improve the survival of eggs and juveniles by controlling conditions (and losses) associated with incubation and rearing. These increases can lead to much larger returns of adults.

Hatcheries can operate in many different ways that influence the kinds of effects and the level of associated risk. The Cedar River Hatchery Program is being developed to reduce the potential for adverse effects generally attributed to hatchery programs. While some differences are expected between hatchery and wild production, the measures described below and those incorporated in the operating protocols are intended to reduce the risk of significant adverse effects.

Learn more about the goals of the hatchery and who is involved.

Who is working on this project?

What are the Goals and Concepts?

What about the effects of the hatcheries?

What are the results of the present sockeye hatchery?

What is the adaptive management plan?

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This hatchery is an incubation facility so fry will be released soon after emergence. The fry will rear naturally in Lake Washington. Some studies have suggested that extended rearing in a hatchery may alter behavior of hatchery fish, making them less fit to survive. Longer holding periods increase the risk of disease problems as well.
A locally-adapted sockeye stock is being used. By using a locally-adapted stock, there is a better chance that the fish produced by the hatchery will have the timing and other genetically determined traits that are needed to be successful in Cedar River/ L. Washington system.

The hatchery will rely on a random mix of hatchery and naturally- produced sockeye for eggs each year. This allows certain natural selection pressures to help maintain a healthy and productive stock.

Long term monitoring to evaluate the hatchery's performance and effects. Approximately $4 million is committed to gather data on the key uncertainties about the program's performance and effects as identified in the adaptive management plan.

Commitment to analyze results using independent scientific review and to make changes when needed.

What do we know about the results of the present sockeye hatchery?
The operation of the interim sockeye hatchery at Landsburg since 1991 has provided opportunity to evaluate culture methods that are unique to sockeye culture and test their effectiveness. Methods that were developed in Alaska to control a viral disease (IHN virus) common to all sockeye populations have proven effective at the Landsburg site. In addition, useful information on incubator performance, water supply, incidence of virus, development rates, emergence timing and other parameters has been generated through the operation of the interim hatchery. This experience is valuable in guiding design and program decisions for the replacement hatchery.

All sockeye fry released from the Landsburg hatchery have been marked since the program began in 1991. These marked fish have provided the opportunity to identify hatchery-produced fish as they grow and ultimately return as adults. Recovery of the adult carcasses and removal of the marked bone (otolith) in the fish's head provides the basis for determining the origin of the fish through banding patterns that are established during incubation. Otolith marking and sampling have allowed the following analyses to be initiated:
Estimates of annual wild and hatchery sockeye fry production from the Cedar River. WDFW has completed estimates of outmigrants through 1999 and have preliminary estimates for 2000.

Surveys of Bear Creek, a northern tributary to Lake Washington, were done in three years (1998-2000) to determine to what extent hatchery-produced sockeye were straying into that system. The concern is that if the level of straying is too great, that the genetic composition of the Bear Creek sockeye population could be altered. WDFW issued a paper in January, 2001, entitled "Straying by Cedar River Hatchery-Produced Sockeye Salmon to Big Bear Creek, WA" by Kurt Fresh, Steve Schroder, Eric Volk and Jeff Grimm. No Cedar River hatchery marked fish were found among the 1,251 fish that were sampled during the three-year study period.

University of Washington investigators, using microsatellite loci, have examined the genetic relationships of sockeye and kokanee from the Lake Washington basin and from potential founder populations ("Investigations of Genetic Variability within and between Lake Washington Sockeye Salmon Populations using Microsatellite Markers", January 2000 by Paul Bentzen and Ingrid Spies). The paper describing results from the second year of work is in review.

Otoliths have been collected from carcasses in the Cedar River each year since 1995. Recent funding to the Washington Department of Fish and Wildlife permitted the otoliths to be read and analyzed. Results from the following analyses have not yet been finalized, but are expected soon.
· Effects on timing and release location of fry on spawning location of adult returns.
· Survival estimates of wild and hatchery fry
· Size of adults by sex and by origin
· Proportion of adult return to the Cedar River originating from hatchery releases
· Proportion of broodstock that was of hatchery origin.