Chinook salmon orient into the water current of the swim flume during a performance trial.
How do salmon know where their home is when they return from the ocean?
Salmon come back to the stream where they were 'born' because they 'know' it is a good place to spawn; they won't waste time looking for a stream with good habitat and other salmon.
Scientists believe that salmon navigate by using the earth’s magnetic field like a compass. When they find the river they came from, they start using smell to find their way back to their home stream. They build their 'smell memory-bank' when they start migrating to the ocean as young fish.
If a salmon can’t find its stream, some continue to search for the right stream until they use up all their energy and die, but most simply try to find other salmon with which to spawn.
Learn more: Western Fisheries Research Center - Questions and Answers about Salmon
Related Content
Are salmon endangered worldwide?
No, salmon are not endangered worldwide. For example, most populations in Alaska are healthy. Some populations in the Pacific Northwest are much healthier than others. These healthy populations usually occupy protected habitats such as the Hanford Reach on the Columbia River and streams of Olympic National Park. Learn more: Western Fisheries Research Center - Questions and Answers about Salmon
How far do salmon travel?
Salmon first travel from their home stream to the ocean, which can be a distance of hundreds of miles. Once they reach the ocean, they might travel an additional 1,000 miles to reach their feeding grounds. Learn more: Western Fisheries Research Center - Questions and Answers about Salmon
How long do salmon usually live?
Most salmon species live 2 to 7 years (4 to 5 average). Steelhead trout can live up to about 11 years. Learn more: Western Fisheries Research Center - Questions and Answers about Salmon
How many species of salmon are there and how large can they get?
There are seven species of Pacific salmon. Five of them occur in North American waters: chinook, coho, chum, sockeye, and pink. Masu and amago salmon occur only in Asia. There is one species of Atlantic salmon. Chinook/King salmon are the largest salmon and get up to 58 inches (1.5 meters) long and 126 pounds (57.2 kg). Pink salmon are the smallest at up to 30 inches (0.8 meters) long and 12...
When can salmon be seen migrating to their spawning area?
Most Pacific salmon can be seen migrating from spring though fall, depending on the species. Most adult Atlantic salmon migrate up the rivers of New England beginning in spring and continuing through the fall as well, with the migration peaking in June. Learn more: Western Fisheries Research Center - Questions and Answers about Salmon
Where are salmon most endangered?
Certain populations of sockeye salmon, coho salmon, chinook salmon, and Atlantic salmon are listed as endangered. Sockeye salmon from the Snake River system are probably the most endangered salmon. Coho salmon in the lower Columbia River may already be extinct. Salmon are not endangered worldwide. For example, most populations in Alaska are healthy. Some populations in the Pacific Northwest are...
Why are there so few salmon left?
There are many reasons for the decline in salmon populations. Logging an area around a stream reduces the shade and nutrients available to the stream and increases the amount of silt or dirt in the water, which can choke out developing eggs. Dams cause fish to die from the shock of going through the turbines and from predators that eat the disoriented fish as they emerge from the dam. Overfishing...
Why do salmon change color and die after they spawn?
Salmon change color to attract a spawning mate. Pacific salmon use all their energy for returning to their home stream, for making eggs, and digging the nest. Most of them stop eating when they return to freshwater and have no energy left for a return trip to the ocean after spawning. After they die, other animals eat them (but people don't) or they decompose, adding nutrients to the stream...
Why do salmon eggs come in different colors?
Salmon eggs (roe) range in color from pale yellowish-orange to dark reddish-orange. The color varies both by species and within species and is determined by water temperature, sediment composition, age, and other factors. The eggs vary in size from the tiny sockeye roe (average ¼ inch or 5.6 mm) to the large chum roe (average almost ½ inch or 8.3 mm). Also, if a salmon egg does not get fertilized...
Chinook salmon orient into the water current of the swim flume during a performance trial.
Sockeye salmon preparing to spawn upstream of Cle Elum Dam, Washington.
Sockeye salmon preparing to spawn upstream of Cle Elum Dam, Washington.
Adult Sockeye Salmon in Drano Lake, WA on July 15th and 16th 2015.
Adult Sockeye Salmon in Drano Lake, WA on July 15th and 16th 2015.
by Amy East USGS Research Geologist
- Hear about river response to the largest dam removal in history.
- Causing disturbance as a means of restoration: how well does it work?
- Will legendary salmon runs return?
by Amy East USGS Research Geologist
- Hear about river response to the largest dam removal in history.
- Causing disturbance as a means of restoration: how well does it work?
- Will legendary salmon runs return?
A mature salmon returns to a shallow stream reach to spawn.
A mature salmon returns to a shallow stream reach to spawn.
Salmon and steelhead migrating through Bonnerville Dam.
Salmon and steelhead migrating through Bonnerville Dam.
Spawning sockeye salmon in the Grand Central River, near Nome, Alaska
Spawning sockeye salmon in the Grand Central River, near Nome, Alaska
Assisted migration of coho salmon: Influences of passage and habitat availability on population dynamics
Seventy-five years of science—The U.S. Geological Survey’s Western Fisheries Research Center
Related Content
Are salmon endangered worldwide?
No, salmon are not endangered worldwide. For example, most populations in Alaska are healthy. Some populations in the Pacific Northwest are much healthier than others. These healthy populations usually occupy protected habitats such as the Hanford Reach on the Columbia River and streams of Olympic National Park. Learn more: Western Fisheries Research Center - Questions and Answers about Salmon
How far do salmon travel?
Salmon first travel from their home stream to the ocean, which can be a distance of hundreds of miles. Once they reach the ocean, they might travel an additional 1,000 miles to reach their feeding grounds. Learn more: Western Fisheries Research Center - Questions and Answers about Salmon
How long do salmon usually live?
Most salmon species live 2 to 7 years (4 to 5 average). Steelhead trout can live up to about 11 years. Learn more: Western Fisheries Research Center - Questions and Answers about Salmon
How many species of salmon are there and how large can they get?
There are seven species of Pacific salmon. Five of them occur in North American waters: chinook, coho, chum, sockeye, and pink. Masu and amago salmon occur only in Asia. There is one species of Atlantic salmon. Chinook/King salmon are the largest salmon and get up to 58 inches (1.5 meters) long and 126 pounds (57.2 kg). Pink salmon are the smallest at up to 30 inches (0.8 meters) long and 12...
When can salmon be seen migrating to their spawning area?
Most Pacific salmon can be seen migrating from spring though fall, depending on the species. Most adult Atlantic salmon migrate up the rivers of New England beginning in spring and continuing through the fall as well, with the migration peaking in June. Learn more: Western Fisheries Research Center - Questions and Answers about Salmon
Where are salmon most endangered?
Certain populations of sockeye salmon, coho salmon, chinook salmon, and Atlantic salmon are listed as endangered. Sockeye salmon from the Snake River system are probably the most endangered salmon. Coho salmon in the lower Columbia River may already be extinct. Salmon are not endangered worldwide. For example, most populations in Alaska are healthy. Some populations in the Pacific Northwest are...
Why are there so few salmon left?
There are many reasons for the decline in salmon populations. Logging an area around a stream reduces the shade and nutrients available to the stream and increases the amount of silt or dirt in the water, which can choke out developing eggs. Dams cause fish to die from the shock of going through the turbines and from predators that eat the disoriented fish as they emerge from the dam. Overfishing...
Why do salmon change color and die after they spawn?
Salmon change color to attract a spawning mate. Pacific salmon use all their energy for returning to their home stream, for making eggs, and digging the nest. Most of them stop eating when they return to freshwater and have no energy left for a return trip to the ocean after spawning. After they die, other animals eat them (but people don't) or they decompose, adding nutrients to the stream...
Why do salmon eggs come in different colors?
Salmon eggs (roe) range in color from pale yellowish-orange to dark reddish-orange. The color varies both by species and within species and is determined by water temperature, sediment composition, age, and other factors. The eggs vary in size from the tiny sockeye roe (average ¼ inch or 5.6 mm) to the large chum roe (average almost ½ inch or 8.3 mm). Also, if a salmon egg does not get fertilized...
Chinook salmon orient into the water current of the swim flume during a performance trial.
Chinook salmon orient into the water current of the swim flume during a performance trial.
Sockeye salmon preparing to spawn upstream of Cle Elum Dam, Washington.
Sockeye salmon preparing to spawn upstream of Cle Elum Dam, Washington.
Adult Sockeye Salmon in Drano Lake, WA on July 15th and 16th 2015.
Adult Sockeye Salmon in Drano Lake, WA on July 15th and 16th 2015.
by Amy East USGS Research Geologist
- Hear about river response to the largest dam removal in history.
- Causing disturbance as a means of restoration: how well does it work?
- Will legendary salmon runs return?
by Amy East USGS Research Geologist
- Hear about river response to the largest dam removal in history.
- Causing disturbance as a means of restoration: how well does it work?
- Will legendary salmon runs return?
A mature salmon returns to a shallow stream reach to spawn.
A mature salmon returns to a shallow stream reach to spawn.
Salmon and steelhead migrating through Bonnerville Dam.
Salmon and steelhead migrating through Bonnerville Dam.
Spawning sockeye salmon in the Grand Central River, near Nome, Alaska
Spawning sockeye salmon in the Grand Central River, near Nome, Alaska