Most Pacific Salmon die after depositing their eggs — these fish become an important source of food and nutrients for the local ecosystem. And research shows only 5 to 10% of Atlantic Salmon will return to the ocean and make the journey again next year.
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.
That’s super cool, because salmon are one of only a few fish in the whole world that can live in both fresh and saltwater ! But between September and November every year, a salmon’s instinct to spawn (that means lay eggs) kicks in.
Why do salmon die after spawning?
First off, not all salmon die after spawning, just six members of the genus Oncorhynchus. The reason for this life strategy is fairly simple, pacific salmon live in some of the least nutrient rich rivers in the world.
You could be asking “What happens to salmon after they die?”
After they die, other animals eat them (but people don’t) or they decompose, adding nutrients to the stream. Unlike Pacific salmon, Atlantic salmon do not die after spawning, so adults can repeat the spawning cycle for several years. Are salmon endangered worldwide?
It does not take very long for the salmon to die after spawning. This is caused by their lack of nutrition and decaying of their nutrients. It may take anywhere from a few days to a few weeks for salmon to die. Which salmon do not die after spawning? Unlike the Pacific Ocean salmon, the Atlantic Ocean salmon do not die after spawning.
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.
Why are salmon populations declining?
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.