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Name:    jeffrey
Status:    other
Age:    20s
Location: N/A
Country: N/A
Date: 2000-2001

I know that the salmon undergo a dramatic physical change when they come from the salt water into freshwater streams. My question is when this happens, do they just stop eating and are they dying once they hit the fresh water? Thanks.

Salmon participate in what has been described as "Big Bang" reproduction. Prior to returning to their spawning grounds from the ocean, they convert much of their body mass to eggs and sperm production. This effort to migrate up the river does not allow for adequate feeding periods for they only have a limited time before their death. They are using their body mass as their source of nutrients and energy. This focused effort depletes their body resources and after laying eggs and sperm milting, they die.

Steve Sample

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