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Salmon Fishing
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Other Interesting Salmon
Facts: |
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Did You Know? |
A 2
lb. salmon and a 40 lb. salmon have exactly the same number of scales!
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What makes a Pacific salmon a Pacific Salmon? |
Most Pacific salmon are anadromous: they are born in fresh water, spend
their adult lives in the saltwater oceans and return to their natal rivers,
or lakes, to spawn. They are also semelparous, dying after they spawn.
Atlantic salmon, Salmo salar, are anadromous but may spawn more than
once.
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What is the record for oldest age of salmon and steelhead? |
- Chinook: 7 yrs.
- Sockeye 7 yrs.
- Coho 4 yrs.
- Chum 6 yrs.
- Pink 2 yrs.
- Steelhead 8 yrs.
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Is a steelhead a trout or a salmon? |
A steelhead is a rainbow trout that migrates to sea
as a juvenile and returns to fresh water as an adult to spawn. The
steelhead does not always die following spawning and may spawn more than
once and return to the sea after each spawning.
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| What makes a Pacific
salmon a Pacific Salmon? |
Most Pacific salmon are anadromous: they
are born in fresh water, spend their adult lives in the saltwater oceans and
return to their natal rivers, or lakes, to spawn. They are also semelparous,
dying after they spawn. Atlantic salmon, Salmo salar, are anadromous but may
spawn more than once.
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| Why do Pacific salmon die after they
spawn? |
Dying salmon increase the survival rate
of their offspring by sacrificing themselves as food for bears, eagles,
gulls. Their carcasses sink, wash up on shore, and provide an important
protein source for other animals in the food chain. As they decompose they
also fertilize lakes and vegetation along shore. Meanwhile the predators
are busy with bigger fish allowing the salmon eggs to develop and
return to the sea.
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| How many species
of Pacific salmon are there? |
There are seven species of Pacific
salmon, plus two freshwater species.
Five species are found in Alaskan waters:
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- Sockeye (oncorhynchus nerka)
- Pink (oncorhynchus gorbuscha)
- Chum (oncorhynchus keta)
- Coho (oncorhynchus kisutch)
- Chinook (oncorhynchus tshawytscha)
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Two species of Pacific salmon, masu, Omasou,
and amago, O. rhodurus, are only found in Asian waters.
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What are the stages of a salmon's life
cycle? |
There are six stages of a
salmon's life cycle: eggs, alevin, fry, smolt, adult, and spawners.
The salmon life cycle begins, and ends, as the spawning process in fresh
water. The female chooses a site and builds a redd, or nest, by digging in
the gravel with her tail. She then deposits her eggs, one, or more males
then fertilize the eggs. She then covers the eggs and repeats the process.
Adult salmon guard the site until their death.
In late winter, eggs hatch from the redds. Young alevin in the gravel live
off the nutritious yolk sac that hangs off their undersides for up to four
months. Then they swim up from the gravel to start feeding on live prey.
Some species head straight to the ocean as fry, while others remain in the
stream for another year.
Next, the smolt stage occurs. The juvenile salmon swim downstream and
undergo major physiological changes (smolting) while adapting to salt water
in estuaries, where freshwater rivers meet the saltwater seas.
Once in the ocean, they travel in schools. After one
to seven years, depending on the type of salmon, they return to their home
rivers to spawn in the same stream they were born in.
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| How many salmon
survive to spawn? |
Less than 2% of salmon hatched in streams will return
to spawn. For example, of 2500 hatched eggs, less than 375 live to be fry.
Of those, less than 30 survive to be smolts. An average of 5 reach adult
stage and 2 return to spawn.
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