Hi there,

I'm doing research on eccentrics and have heard that all fish swim upsteam, and not with the natural flow. Is this correct?

Taniarts

I know salmon swim up stream to spawn. It's a rough trip for them. I have not heard of any other fish that does this but I am sure they are not the only ones that do this

I don't know but considering the salmons, the small fishes have to go to the sea, right? Then, the have to swim downstream!

Living in Alaska myself, I can tell you that Salmon are NOT small fish, one has been recorded as high as 100 pounds and I have personally caught one that weighed 65 pounds.

Now, I do not know about other fish, but yes, Salmon swim upstream from the ocean to where they were born to spawn and eventually die.

No, no no, I was meaning the fishes that hatched, baby fishes in other words, they need to first go to the sea, then return to the river? Or, they grow there, big enough for a long trip and comes back?

All fish do not have to swim upstream all the time, if that's what you mean. If they did that, they would all end up in tiny streams at the headwaters of major rivers. Fish can swim both upstream and downstream.

As for fish like salmon that leave the ocean to spawn in rivers, of course they have to swim upstream from the ocean. And of course the hatchlings swim the other way down to the ocean.

Fish can swim in either direction depending on what they need or want to do, just as we can walk up hill and down hill.