Hatcheries & Mitigation
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etween 1932 and 1973, the Columbia River was totally reshaped with the construction of dams for hydropower, flood control, recreation, and (theoretically) conservation. Today, more than 400 dams exist in the Columbia River Basin from British Columbia to the mainstem, which itself holds 11 major dams.1 They are managed by federal agencies including U.S. Army Corps of Engineers and Bureau of Land Management, and by state agencies and tribal entities including the Yakama and Nez Perce.
The White Sands Creek satellite facility, managed by Idaho Department of Fish and Game. Here, in the high tributaries of the Lochsa River, some adult salmon that have successfuly returned to their home water to spawn are captured, processed, and then taken to the Clearwater Hatchery near Orofino for spawning. They are later released back into White Sands Creek.
From a river flowing freely for about 1,200 miles from Columbia Lake in British Columbia to the Pacific Ocean, the Columbia was converted into a series of lakes stretching between dams that constantly control water flow from one lake to the next. The same happened on tributaries including the Clearwater River in Idaho and Washington and the Snake River in Idaho.
Some dams have fish ladders that allow spawning fish to swim up and through, but on others only the smolts heading downstream to the ocean can pass through the dams. Hatcheries were created above blocking dams to replace local populations--salmon and steelhead--that never could return to spawn naturally in their native waters. Thus some hatcheries were assigned to replace fish rather than increase the harvest.
Wild Salmon vs. Hatchery-Bred
In the wild, female salmon lay their eggs and males fertilize them in sand or gravel beds under unimpeded, flowing freshwater. Pacific salmon adults then soon die. From the eggs come "alevin" (uh-LEV-un), immature fish with egg sacs attached to their bellies until the enclosed nutriment is consumed. Now looking like fish, the surviving "fry" hide from predators by taking on camouflage markings that match their surroundings; they hide under surface detritus, and feed below surface. They grow to "parrs" or "fingerlings" (so named because of their pinkish bar-shaped markings).
After maturing further, to the "smolt"--young adult--stage, salmon and steelhead are ready to leave freshwater. They begin the long and dangerous downstream journey toward the ocean. The smolts' age varies by species, being as low as one week in chum and pink salmon, to as great as 36 months in sockeye ("red salmon"). Pausing in the Columbia estuary where fresh- and saltwater mix, the creatures acclimate until moving out into the Pacific Ocean for their adult lives. They travel hundreds of miles from the mouth of the Columbia, so that maybe even some "wild salmon" netted at sea began life in a hatchery. In the late 1990s, Columbia River Basin hatchery fish accounted for about 50% of fall chinook, 70% to 80% of spring/summer chinook, 70% of steelhead, and 95% of coho.2
In traditional hatcheries, salmon and steelhead on their spawning run are captured and monitored. When the females are ready to lay their eggs, people harvest eggs and sperm and artificially inseminate the eggs. Fertilized eggs are counted and placed in trays in carefully monitored indoors facilities. The hatched alevins are moved outdoors into concrete rectangles open to the sky, with no camouflage pattern or sheltering detritus. Nutritionally balanced feed is thrown onto the water. With open space instead of riverine trees species surrounding the ponds, fewer predators can threaten--or educate--salmon and steelhead about natural dangers. Humans again handle the fish at smolt stage, planting them in designated streams for harvest, sportfishing, and/or species survival.
Fish bred in traditional hatcheries, according to Silas Wittman, a former Nez Perce Fisheries manager, look
like shiny nickels when they're released into the river. They've never seen a predator in their life, they have no camouflage, and they've been trained to only eat from the water's surface.3
Do Hatcheries Mitigate Changes?
Yoosa Creek fish hatchery on the Lewis and Clark Expedition's path in Idaho.
Fish hatcheries were intended to "mitigate," or make less severe, human changes that altered fish life cycles--changes from dams, riverside development including roading, and environmental changes caused by human activities from manufacturing to waterskiing. Goals of an individual hatchery could include any combination of: preserving the species, augmenting the harvest, maintaining a species in a location where an altered environment no longer supported it, increase the population where it has decline, restoring a salmon population to an area where it had died out, and researching for future hatchery and river improvements.
By the 1990s, scientists had begun to divide into those who believed that hatcheries succeeded and those who saw them as failures. Arguments against hatcheries include that they:
• lessen genetic diversity within a population through inbreeding;But some authorities argue that so many other changes have been made to the environment that hatcheries are now the only way to keep anadromous fish species alive in the Columbia River and its tributaries. While scientists continue to wage this debate, little of it has leaked to the popular press.
• lessen genetic diversity among different populations by mingling them in hatcheries and when planting them;
• semi-domesticate the fish;
• easily spread diseases among fish populations;
• become self-perpetuating rather than achieving the goal for a certain fish population and then closing down.4
A New Look in Hatcheries
In recent years, new-style hatcheries have begun to appear in the Northwest. One in the Columbia River Basin is sponsored by the Yakama Nation (at Cle Elum, Washington, dedicated 1997) under the Northwest Power and Conservation Council.5 The Cle Elum Supplementation and Research Facility uses "semi-natural treatment" methods, beginning by randomly catching spawning salmon from the Yakima River. A control group is raised in a traditional hatchery, with a second group given ponds with underwater camouflage paint, underwater feeders, and natural surface and streamside cover. The hatchery's first adult salmon returned in 2001, and studying them continues.
In 2005, the Nez Perce Tribe opened a salmon hatchery at Cherrylane, Idaho, one that even more closely mimics the natural setting. Fish swim in S-shaped concrete ponds painted underwater with camouflage, through which flows diverted creek water over rocks, sunken logs, and a natural insect population. "Streamside" riverine trees and shrubs are planned. Water-flow speed, volume, and temperature are altered to imitate seasonal changes of wild streams.
At the Nez Perce hatchery, the young salmon are not protected from predators like kingfishers and mergansers. Satellite facilities allow the smolts to acclimate to the specific streams they are meant for, before being released. The goal--not measurable until 2010 and after--is that the mature salmon will return to their release locations to spawn, becoming a naturally sustaining population.
While scientists continue to argue over the value of hatcheries in general, Nez Perce Tribe Fisheries Department manager Dave Johnson places the Cherrylane hatchery in his people's cultural context:
We will treat these fish with the respect they deserve. They are not ours to do with what we will. Rather, they are a part of us; they share our world.6
1. William Lang, Professor of History at Portland State University and former Director of the Center for Columbia River History. Posted at http://www.ccrh.org/river/history.htm and accessed 03/29/05.
2. Statistics from National Marine Fisheries Service, quoted in Artificial Production Review, p. 1.
3. Quoted in Jeremy FiveCrows, "The Nez Perce Tribe Has Combined Traditional Knowledge with State-of-the-Art Science To Create an Innovative Hatchery in the Heart of Their Reservation," Wana Chinook Tymoo: The Magazine of the Columbia River Inter Tribal Fish Commission, posted on http://www.critfc.org/wana/hatchery.html/ and accessed 04/01/05.
4. Artificial Production Review, pp. 108-121.
5. Northwest Power and Conservation Council at http://www.nwcouncil.org/library/2003/2003-14/cleelum.htm/
With thanks to Don Skaar, Pollution Control Biologist, Montana Department of Fish, Wildlife and Parks; and Mike Demick, Regional Conservation Educator, Idaho Department of Fish and Game.
Funded in part by a grant from the Idaho Governor's Lewis and Clark Trail Committee.