Salmon Habitat Resources
Salmon Cycle
The Salmon Life Cycle
A female salmon may lay 3000-5000 bright pink eggs in the nest called a redd that she digs in the gravelly streambed. After the male fertilizes the eggs they absorb water and become sticky. The female moves upstream to lay more eggs. Gravel from the next nest is pushed downstream and covers the first nest. The eggs grow and develop for a few months before hatching.
Only about 20% of the eggs in a stream will hatch. Many of the eggs succumb to predators, oxygen deprivation or physical damage. A newly hatched salmon or alevin emerges with a yolk sac attached to its abdomen. Alevins live in the gravel and survive by absorbing the protein, sugars and vitamins from their yolk sac. After a few weeks the yolk is gone and the small fish called parr move into deeper water and begin to find food on their own. Vertical stripes on its sides help to hide the parr from predators.
Salmon parr remain in freshwater feeding and growing for many months or even years before migrating downstream to saltwater. When they are about as big as a human finger they are called fingerlings. They hide and feed among the plants and wood debris in the river.
Feeding in the estuary where fresh and saltwater intermingle doubles or triples the size of the smolt. After a few weeks of growing and adjusting to saltwater, young salmon swim into the ocean. The ocean provides salmon with abundant food including shrimp and other crustaceans which help to color their flesh pink. Adult salmon also eat anchovies, herring and other fish. In the ocean, salmon are a bright silver color. They spend one to five years at sea depending on their species.
Salmon migration is an astounding feat still not fully understood. Juvenile salmon imprint or memorize the unique organic odors of their home streams. As returning adults they can detect and recognize these odors and follow them upstream sometimes to the exact areas where they hatched. Before making this upstream migration, however, the salmon must find its way to within smelling distance of the river. Salmon from throughout the Pacific Northwest intermingle in the oceans where they travel in broad circular patterns. It is thought that they use currents, salinity and temperature patterns, the sun, stars, and the earth's magnetic field to aid them in traveling from sea to river mouth, where their sense of smell guides them to the river or stream where they first hatched.
Not all salmon return to their home stream at the same time of year. There are different runs of salmon that return from the sea at various times and seasons. Each run is genetically unique and specifically adapted to their stream. Some salmon migrate over 1000 miles up river to spawn. On their way, each species develops unique coloration and patterns. Male salmon spawners also develop long, hooked snouts and sharp, canine-like teeth. Changes in the female are similar but less pronounced. They gather at the river's mouth to await heavy rains before moving upstream. During upstream migration salmon do not feed.
When salmon reach their spawning grounds males and females pair off. Females look for rippling waters and clean streambed gravel that can be swept aside with broad tail strokes. The scooped-out gravel forms a depression about the shape of the female's body but twice as long. Males compete to spawn with the female. Sometimes smaller males called jacks are also present. Jack salmon are small because they migrate after only a year in the ocean but can spawn nevertheless. The female deposits some of her eggs in the redd and the male fertilizes them with a milky cloud of sperm called milt. Eggs are laid in batches deposited within the redd. Spawners guard the nest to protect it from intruders. Most Pacific salmon die within one to two weeks after spawning.
The Nutrient Cycle
Although Pacific salmon do not survive to care for their young, their deaths are an important factor in the survival of young salmon and the health of the ecosystem. The decaying bodies of salmon that have spawned release nutrients that support plant and insect life that in turn nourish salmon parr or fry. Some 22 species of mammals or birds directly feed on living or dead salmon, including: raccoons, otters, humans, bears, flying squirrels, jays, moles and shrews. Altogether, 98 species have a direct or indirect link to salmon through the food web. Salmon are a valuable source of nutrients. Adult salmonids gain more than 95% of their final weight while they are in the ocean. When they return to spawn and die, they transfer those nutrients including nitrogen, phosphorous and carbon to freshwater systems. The nutrients from salmon are a key link in the overall productivity of our aquatic and terrestrial ecosystems.
Hazards for Salmon
Salmon face many hazards both natural and man-made at each stage of their life cycle. Natural hazards include drought, floods, predators and inadequate food supplies. Salmon have evolved with these natural hazards and have developed adaptations to cope with them. They are unable to cope successfully with most human-created hazards. There are four primary factors that have led to the decline of Pacific Northwest salmon.
Habitat destruction - Throughout their lives salmon depend on cold, clean, well-oxygenated water. Their freshwater habitat must include plants to shade streams, deep pools of water to rest in and clean gravel for spawning. Poor logging practices, grazing, mining, road-building and urban development often destroy streamside vegetation, erode the land and fill streams with silt that smothers gravel beds.
Harvest - during the heyday of Northwest commercial fishing salmon stocks seemed limitless. We know now that overfishing, combined with habitat destruction, was one of the first causes of salmon decline. Harvest today is highly regulated but can still be a problem when endangered stocks are caught unintentionally with non-endangered ones. Technology has made it possible to harvest many or even all the fish. Fishing must be carefully managed so that salmon continue to be a harvestable resource.
Hydropower - Hydroelectric dams block migration to and from the ocean. Many dams lack fish ladders. The downstream migration of young salmon is hampered by the huge reservoirs of water that form behind dams where juvenile fish are exposed to unhealthy conditions, high temperatures and predators. Fish that pass through the turbine blades of dams are often injured or killed.
Hatcheries - Hatcheries developed as a way to compensate for the loss of salmon habitat to dams, agriculture and urbanization. They effectively protect salmon eggs and rear young fish to the time of freshwater release. At that point, salmon must cope with whatever conditions exist for the downstream migration, in the ocean, and later, as they return to spawning grounds. Hatchery-reared fish may transmit diseases to wild fish and they compete with wild fish for food and habitat. Interbreeding with hatchery fish dilutes the genetic diversity and vigor of wild stocks. Modified hatchery practices can help to enhance salmon stocks but will never be a substitute for habitat protection and restoration. Despite large numbers of hatcheries in Washington State, salmon runs in the Northwest have steadily declined. Fewer fishing days are available to fishermen than ever before. Less fish are caught and the size of those fish tends to be smaller than salmon of the past.
Two Native American Perspectives from First Fish - First People Salmon Tales of the North Pacific Rim
"For thousands of years the original peoples of the West Coast of North America practiced sustainable conservation harvesting through complex patterns of strictly observed trade laws and internal practice. In salmon harvesting, everyone observed ceremonially protected customs which embedded respect for their source of life. Such customs, exampled by first salmon rites, are common throughout the Pacific Northwest Coast peoples. Salmon harvesting was strictly regulated in various ways by knowledge-keeper chiefs in their various jurisdictions, no matter where on the river system, to allow for upstream takes with the goal of preserving future full spawning cycles. These conservation methods are the source of an original and inherent right of those peoples to continue to harvest and enjoy their ancestors' magnificent legacy Today all five salmon species are battling for their survival under the onslaught of the most severe pressures in their long history. In little over a century, the colonization of the Americas has laid to waste the results of thousands of years of good conservation practiced by the original peoples... Where salmon is the most important source of life and the outward expression of God, the spirit of a whole people becomes wounded beyond expression when that source is annihilated. I have seen that deep despair in the many river peoples who can no longer harvest salmon. There are many such peoples in the U S. and Canada who cannot practice their legal right to harvest for food or trade, though such rights were bitterly fought for and won in hostile courts. The salmon runs are gone, nearly extinct or so heavily polluted that eating them poses serious health risk.
Jeanette C. Armstrong (Okanagan)"There is a striking parallel between the salmon as they struggle upstream to spawn and the tribes of the Northwest as they struggle to retain their treaty right to fish. Both continue to meet and overcome great obstacles and the most common threat to them both has been politics. When conflicts have arisen over this past century, it is usually the salmon and the tribes that have lost out to the more powerful political interests of big business, timber, railroad, mining, farming and hydroelectric power.
One arena where both the tribes and the salmon began winning, however, is in the courts, particularly the United States Supreme Court. It will surprise many to know that court battles over fishing began very early and have continued to the present day. Tribes have persistently fought for the continued right to fish for over 150 years and what becomes clear is that a way of life was at stake, a tradition and a culture. Even though much of our way of life has been lost, this right to fish has never been surrendered.
Sandra Osawa (Makah)
Orcas need bountiful salmon runs
Overall salmon runs are in deep and historic decline due to a variety of historic, complex, and interconnected causes. The four H’s: Habitat destruction; Hydropower blockages; Harvest impacts; and Hatchery impacts, all reduce salmon populations. Salmon are the lifeblood of Pacific NW ecosystems, providing nourishment for a wide array of wildlife, including transport of vital marine nutrients to forested watersheds.
For thousands of years Southern Resident Orcas have specialized on Chinook salmon, the largest, fattiest of salmon species. Spawning in every river system from the Aleutians to the California Valley, one of the thousands of runs of Chinook have been abundant year around, especially along the Washington coast and within the Salish Sea. The ancient ancestors of Southern Resident orcas made these waters the core of their foraging habitat, finding Chinook salmon of various origins throughout their range. But increasingly over the past 150 years, as settlers built their farms, towns and industries, those salmon have largely disappeared all along the coastline and inland waters.
Persistent toxic contamination, especially polychlorinated biphenyls (PCBs) and other organic chemicals, like DDT and persistent aromatic hydrocarbons (PAHs), continue to leach into the marine ecosystem and move inexorably through the food web. Over decades these contaminants have gradually become lodged in the whales' blubber layers in massive quantities, sometimes with lethal results.
Levels of PCBs and PBDEs (flame-retardants added to manufactured products) attach to fat cells and accumulate over the life of marine mammals, severely impairing development and immunity in orcas, but fortunately are gradually decreasing throughout the marine food web, including in orcas and humans.
To understand the deep interconnections between salmon and orcas, and insects and crab larvae and eagles and rockfish and all the other inhabitants of the Salish Sea, go to:
Pacific Salmon and Wildlife: The Cedarholm Report
Ecological Contexts, Relationships, and Implications for Management
Jeff Cederholm shows a salmon to students
Photo by Mike Salsbury/The Olympian
"Salmon act as an ecological process vector, important in the transport of energy and nutrients between the ocean, estuaries, and freshwater environments. The flow of nutrients back upstream via spawning salmon and the ability of watersheds to retain them plays a vital role in determining the overall productivity of salmon runs. As a seasonal resource, salmon directly affect the ecology of many aquatic and terrestrial consumers, and indirectly affect the entire food web. The challenge for salmon, wildlife, and land managers is to recognize and account for the importance of salmon not only as a commodity resource to be harvested for human consumption, but also for their crucial role in supporting overall ecosystem health. It is also important that the naive view of wildlife as only consumers of salmon be abandoned. Many species of wildlife for which hard earned environmental laws and significant conservation efforts have been established (e.g., grizzly bears, bald eagles, river otters, killer whales, beaver), play key roles in providing for the health and sustainability of the ecosystems upon which salmon depend. As the health of salmon populations improves, increases in the populations of many of the associated wildlife species would be expected. Salmon and wildlife are important co-dependent components of regional biodiversity, and deserve far greater joint consideration in land-management planning, fishery management strategies, and ecological studies than they have received in the past."
Our own population continues to grow, while our biological support system shrinks.
If the orcas could say only one thing to us, it would probably be:
"Bring back the fish."
Here are some references for guiding salmon recovery:
Whidbey Watershed Stewards, A community group working to restore, preserve, and protect watersheds and water quality on Whidbey Island in Washington.
Save Our Wild Salmon's Columbia & Snake Rivers Campaign
When Lewis and Clark encountered the Snake River (and the Indian people who helped to save their lives) in 1805, five to eight million wild adult salmon returned from the Pacific Ocean to the Snake each year. Today, after the 200th anniversary of Lewis and Clark's expedition, a mere five thousand wild salmon, of all species, return to the Snake. All five species of Snake River salmon and steelhead are listed under the Endangered Species Act, headed toward extinction. The primary reason is that eight federal dams and reservoirs now lie between the inland streams where salmon are born and the ocean where they spend most of their lives.
The Save Our Wild Salmon Coalition was created in 1991 to unite conservationists, sport and commercial fishers, and salmon-based businesses in support of five principles:
return salmon to their rivers: protect and restore spawning, rearing, and migratory habitat;
conserve the genetic heritage and biological diversity of wild salmon populations;
restore productive Tribal and non-Tribal fisheries that allow the rebuilding of wild salmon stocks;
restore wild salmon at least cost to other river users and society as a whole;
foster cooperation among all citizens committed to wild salmon recovery.
Salmon Restoration Activities
Salmon life cycles for teachers
Salmon Restoration Books
Governmental, Tribal and Non-Governmental organizations
working to restore salmon:
Nooksack Salmon Enhancement Association Works to Improve Salmon Habitat in Nooksack County.
Washington Dept. of Fish and Wildlife. As one of the state's overriding environmental challenges, the job of restoring troubled wild salmon stocks involves every Washington citizen. This web site is intended to provide natural resource managers, local governments, volunteers, educators and other citizens with the information and resources they need to become effective participants in salmon recovery. See What Can You Do for guidance in how you can personally act to restore salmon and orcas.
Northwest Indian Fisheries Commission is dedicated to assisting treaty tribes in conducting biologically sound fisheries.
Columbia River Inter-tribal Fish Commission, made up of four Columbia Basin tribes. These tribes are the Confederated Tribes and Bands of the Yakama Nation, the Confederated Tribes of the Warm Springs Reservation of Oregon, the Confederated Tribes of the Umatilla Indian Reservation, and the Nez Perce Tribe.
Salmon Restoration Home Page is a product of Washington State University. Faculty and staff have been invited to share their areas of interest, expertise, and capabilities. Use this link to access information about the people, activities, resources, publications and other educational materials.
Columbia Basin Research Data Access in Real Time (DART) provides forecasts, analysis tools, etc. from the School of Aquatic and Fishery Sciences of the Univ. of Washington.
Organizations, Groups and Alliances dedicated to salmon restoration:
Save Our Wild Salmon is a nationwide coalition of conservation organizations, commercial and sportsfishing associations, businesses, river groups, and taxpayer advocates working collectively to restore self-sustaining, healthy, and abundant wild salmon to rivers, streams and oceans of the Pacific Salmon states.
Long Live the Kings Mission is to restore wild salmon and steelhead and support sustainable fishing in the Pacific Northwest.
Wild Fish Conservancy is a leading advocate for the conservation and recovery of Washington’s wild-fish ecosystems.
Georgia Strait Alliance, based in British Columbia, is involved in a wide variety of initiatives to improve the health of our coastal waters.
Northwest Straits Marine Conservation Initiative "The Northwest Straits is a complex and diverse waterway, rich in beauty and economic benefits. But this ecosystem and some of its marine resources are in serious decline. Bottomfish, sea birds, invertebrates, salmon, and even some populations of marine mammals have declined precipitously since 1980."
American Rivers Rivers are the salves we have relied on over the past year to calm our spirits and give us peace. Maybe rivers have given you the same sort of solace and hope.
Books for Teachers and Students
Field Identification of Coastal Juvenile Salmonids, W.R. Pollard, B.F. Hartman, C. Groot; Harbour Publishing, 1997, 32 pp. - printed on waterproof paper.
"We Are the Same as the Salmon": A Story of Suffering and Perseverance. Thirty years ago, the Shoshone-Bannock Tribes led the effort to save Snake River sockeye salmon from extinction. Today, they’re still fighting for the fish’s survival—along with their own.
First Fish First People - Salmon Tales of the North Pacific Rim, Judith Roche and Meg McHutchison, editors; Seattle: University of Washington Press, 1998, 199 pp. - thirteen writers from two continents and four countries tell the stories of how their cultures are connected to salmon.
Mountain in the Clouds: A Search for the Wild Salmon, Bruce Brown; New York: Simon and Schuster, 1982. - an in-depth look at rivers, salmon, and people on the Olympic Peninsula.
Reaching Home: Pacific Salmon, Pacific People, Natalie Fobes; Seattle: Alaska Northwest Books, 1994, 143 pp. - beautiful photographs and text about the cultural ties to salmon.
Curriculum Resources
Aquatic Project Wild 707 Conservation Lane, Suite 305, Gaithersburg, MD 20878, 301-527-8900.
Wild Salmon and Steelhead Idaho Dept. of Fish and Game, Box 25, Boise, ID 83707-0025, 1-800-422-WILD.
