Why do salmons die after spawning?

Question

Why do salmons die after spawning?

Answer 1

That happens only to the Pacific salmons and not all of them die. A few, called jack salmon, no matter which species they are, make more than one spawning run. After the long run from the ocean to the spawning grounds without eating, the salmon are not in the best of shape and spawning depletes the last of their reserves.

Actually, that's not too bad a way to go. My personal preference is to reach 100 and then be shot by a jealous husband.

Answer 2

Because they're exhausted.  They wear themselves out getting upstream.

Besides, the bears have to eat something.

Answer 3

That's a peculiarity of Pacific salmon.  Atlantic salmon return to the ocean after spawning.  But yes, it's because they wear themselves out in the journey upriver.