This is a summary of a comprehensive review of 950 articles which report on, or mention, problems caused by artificial fish propagation and stocking. The literature review included nearly every key North American article covering fish stocking problems which appeared in professional and popular publications since 1900. The authors' goal was to examine the underlying problems that others have revealed concerning hatchery and stocking programs, and to recommend reform. The authors are: Ray J. White, a fishery consultant from Edmonds, WA; James R. Karr, professor of Fisheries, Public Affairs, and Environmental Health at the University of Washington, Seattle; and Willa Nehlsen, a biological consultant from Portland, OR. The report was prepared for Oregon Trout and financed by the Northwest Area Foundation.

• Since before the turn of the century, fishery scientists and others have reported on the harm caused by hatchery and stocking programs. These warnings have, for the most part, fallen on deaf ears. Fishery managers, politicians, and the general public have assumed that artificial propagation was a good thing without evaluating the long-term effects of these programs.
• Stocking-which is done at great expense while we damage the natural systems that provide fish for free— masks the decline of natural fish stocks, contributing to a false sense of security and complacency about habitat destruction and overfishing. While stocking fish can create temporary local abundance, it often fails and in the long run it becomes a cause for fishery decline rather than a solution.
• Hatchery fish suffer from a variety of genetic and behavioral problems that contribute to their low survival rates in the wild. But more importantly, after they are released into a natural environment, they harm wild fish populations by transmitting diseases, competing for the same resources (food and habitat), feeding on wild fish, attracting other predators, and transmitting genetic defects through interbreeding.
• Instead of trying to mitigate the decline of wild fish stocks through expanded hatchery programs and improved hatchery technology, our resources should be directed toward fixing the problems that caused the population declines in the first place.

The literature review revealed 30 common problems with hatchery fish—both physical and behavioral—which lead to poor growth, survival, and reproduction in the wild. Hatchery managers tend to focus on curing obvious physical problems, such as deformed fins and tails, unnatural coloring, obesity, poor stamina, unsuccessful breeding and disease. But hatchery fish suffer from many, more subtle problems which come from being raised in an artificial environment. These abnormal behaviors can be lethal in the wild. "The behavioral problems may be the most important and most neglected," according to the report.

Vulnerability to predators is the most critical behavior problem. Hatchery-raised fish have not learned to hide from or recognize predators, they tend to hover near the water's surface expecting to be fed (without fear of humans), and they are conspicuously hyperactive. Other behavior problems include inappropriate timing and duration of migration and spawning, and poor homing instincts.

The report also lists 11 ways in which wild stocks and their natural habitat are harmed by hatchery facilities and operations (such as stream contamination from hatchery outflow), and nine ways in which hatchery stocks harm wild fish through intermingling. All told, the literature review revealed more than 50 specific problems with North American hatchery programs documented over the past century. Some of the more egregious and obvious problems—such as low yield and low survival rates—have received repeated attention in articles since about 1920. In recent years, as more data have become available, the volume of articles critical of stocking programs has increased, as has public awareness of the situation.

The most serious problem uncovered in the literature, according to the authors, is that hatchery programs breed a sense of well-being and complacency among the public and public institutions that our fishery problems are being taken care of. Stocking has been used to allow continued overfishing and mitigate for habitat destruction. And hatchery programs deplete funding that could otherwise go for programs (such as habitat protection or restoration, and harvest control) which address the underlying problems and hold more promise for long-term success.

"Despite many studies since the 1930s that revealed shortcomings of stocking programs, and despite the many advances in ecology and genetics since then that also hold clear implications for the field, some fishery agencies and most of the public never did get the message about adverse effects, or they engaged in denial," the report states. The authors note that some hatchery operations have been abandoned based on clear evidence of failure. Unfortunately, some of these operations were restored years later when the lessons of the past were forgotten.

The authors point to recent changes in some fish management programs, such as those in British Columbia and Oregon, which emphasize improving natural production over artificial methods. In 1992, the Oregon Department of Fish and Wildlife adopted a Wild Fish Management Policy to "prevent the serious depletion of any indigenous fish species." This is being done by 1) advocating for habitat protection and restoration, 2) opposing stocking that causes competition, predation, or disease problems for wild fish, and 3) opposing harvest strategies that would endanger the long-term viability of populations.

Recognizing the numerous and well-documented problems with fish hatcheries, the authors believe that artificial propagation and stocking can be beneficial in certain situations. Based on their literature review, the authors recommend that stocking be used sparingly and only in the following circumstances:

Temporary Uses:

• To recolonize native species that were driven from their native habitat by human activity, only after the habitat has been restored and the destructive activity has ceased.
• To colonize newly-formed waters, such as artificial lakes, ponds or the tailwater outflow of dams.
• To help sustain an overharvested or declining fishery economy while fishermen make the transition to other employment.

Long-Term Uses:

• "Put-and-grow" stocking, to maintain a fish population in waters that have little or no reproductive habitat but substantial productive capacity—particularly artificial water bodies, such as reservoirs and reservoir tailwaters—where stocking will not harm the native biota.
• "Put-and-take" stocking, to support an intense recreational fishing in waters that cannot produce enough of a desired fish. This is often done to accommodate seasonal fishing in waters which cannot sustain a year-round fishery (for example, the water is lethally warm in the summer). The authors point to many long-standing aesthetic, ethical and economic objections to creating an artificial fishery in this manner.

1. Stock as few fish as possible, in as few waters as possible, for as few years as possible
2. Integrate stocking programs with ecologically-sound fishery and other aquatic resource management programs, and make stocking programs subordinate to these programs.
3. Design hatchery programs to make them less domesticated.
4. Diagnose the causes of dwindling fish populations before stocking.
5. Stock fish only of those kinds, and in those methods, that have proven effective for the local situation.
6. Stock fish only if it will not harm native fish and other organisms.
7. Keep stocked fish separate from wild populations.
8. Rigorously monitor and evaluate stocking programs, and act on the results.
9. Conduct an environmental impact statement for every proposed fish stocking program, including plans to continue existing fish stocking.