The Elk River is about twenty nine miles long and is located in southwestern Oregon. The river empties into the Pacific at Port Orford.
In 1971, final construction on the Elk River Hatchery was complete. The purpose of the hatchery was to supplement fall Chinook salmon on the Elk and Chetco Rivers, and winter Steelhead on the Chetco River, with both natural and hatchery fish.
When salmon enter the traps, they are collected in holding pens. Younger salmon four to five years old, sometimes referred to as Jacks or Jenny’s, are released. Older mature fish are kept. The precious eggs are collected from the spawning fall Chinook on the Elk river. The eggs are then fertilized, after which they are loaded into trays inside a sheltered building and carefully incubated.
Once hatched, the young fry are deposited into holding tanks where they will live out the next couple of years until they mature into smolt. Depending on the hatchery, they are then released back into the rivers, or they are transferred to aquaculture facilities or fish farms until they reach harvest size.
Pros and Cons of Fish Hatcheries
People have differing opinions on the benefits and disadvantages of fish hatcheries. The most obvious benefit of a fish hatchery is, of course, increasing the numbers of the fish. Fish hatcheries are instrumental in restoring endangered fishing populations, which can mean the difference in the survival of a specific species.
Fish hatcheries also collect critical data involving population numbers, parasites, disease, threats, water quality and genetic diversity, which is vital for future conservation efforts. Fish hatcheries keep a finger on the pulse of the environment, and can help to determine when sections of a river, or in some cases, an entire river as a whole, needs to be shut down for fishing, in an order to replenish decreasing populations of wild fish, or otherwise contribute to the health of the river system.
However, some people are concerned in regards to the genetic diversity of hatchery fish. Wild salmon have stronger genetic diversity, whereas hatchery fish have been concentrated into an increasingly interbreeding population.
To understand this more clearly, in the wild, if one female Chinook salmon lays on average 5,000 eggs, the law of averages states that approximately only one to ten of those will survive to adulthood. Since most females breed with only one male, and the returning Chinook die after spawning, the chances of that one pair having two related individuals spawn together are pretty much slim to none. This ensures genetic diversity, which in turn promotes health, biological fitness, healthy genes to pass on, and a higher chance of survival of the entire species long term.
To contrast this, in a hatchery, one tray of 5,000 eggs may be fertilized by one male, and because of the sheltered incubation and controlled environment, if even 40% of the eggs survive until they are released back into the rivers, that’s 2,000 fish with the same gene pool.
Some hatcheries have addressed this concern by fertilizing the eggs with several males’ sperm to ensure higher genetic diversity. Other hatcheries have implemented selective breeding programs that combat disease resistance, color, growth rate and other factors. However,the hybridization and genetic manipulation used in some of these programs may end up creating more problems than they solve.
Another concern of aquaculture, fish farms and hatcheries is that in some instances these facilities are using synthetic chemicals to induce early spawning. At other facilities, chemicals are pumped into the holding tanks where the fish are held to combat infection and disease.
At some locations, chemicals have been accidentally released into the rivers, which may have the potential for devastating consequences and long-term impact on wild populations of fish and other aquatic life, along with the health of the river ecosystem in general.
The Good News
The good news is that fish hatcheries exist because of positive local, federal and state legislation that has been designed to protect the natural ecosystems and fisheries, with conservation and preservation in mind. Their goal is to mediate a balance between conserving natural resources for the present and future, protecting the environment, and preserving adequate local populations of fish and healthy rivers. This will support both public and commercial fishing industries, which, in turn, sustains local and state-wide economies within individual regions.
The even better news is that most of the hatcheries in place are staffed by people who truly care about the environment and the world we live in. Most of them are biologists, naturalists and conservationists who love their job and connect with the local communities. They strive to work within county, state and federal regulations and guidelines, ensuring that the same beautiful world they grew up in will reside indefinitely for future generations.
At times, they may have a thankless and frustrating job, as many do not see all the behind-the-scenes bureaucracy that they fight along the way. We should appreciate all the hard work that they do in an effort to keep our rivers healthy, our ecosystems intact and our plant and animal life abundant.
For More Information…
If you would like to read further about the conflicting arguments on both sides of the table regarding fish hatcheries, DISCOVER magazine has an interesting article by Matthew Berger you can check out here.
Another interesting article on the debate of the pros and cons of fish farming is located here.
To see the life cycle of the salmon described in detail, please click here.
For parents, home school staff, and teachers: For an interactive educational website that explains the life cycle of a salmon and has a detailed lesson plan complete with printouts, please visit the University of Oregon’s The Salmon Game here.