Stand in the water near the fish symbol and if you have the inspect mode, they will highlight greenish color. Use the crouch to get near them and not scare them away.

Originally posted by Mari:

After running up and down the river that goes through Piastovia and going to the places where the map said there was fish I haven't seen a single one. Do I just wait in the spot for them to spawn? I have fishing spears ready and everything but I just can't find the damn fish

Dear Mari ! Tipp: Press the "Alt" -Button while running and searching ( You can see where the Fish are in the Lake ! ) ! Built a Net or take your Fish spear ! Also, you can see the fishes ( ...also pigs and so on .. ) by pressing the "i" -Button ( map ) ! I hope It will help you ! Greetings from Austria !

Do you have the fish-spear in your hand ? Or did U make a Net near the fishies ? If you have YOUR village, you can build a fisherman's hut, to LET fish somebody, too !

You don't even need a fish spear, just run up to the school of fish in the water with a regular spear and left click them one by one until they're all dead, then pick them all up. They just sit in little schools of 3-8 (depending on type of fish) directly where the spawn markers are on the map.

I'm not sure what the guy mentioning a need to crouch and "sneak up" on the fish was smoking, sounds like realistic gameplay but it isn't accurate at all. Once you spear the first fish in the school, the rest will move at a comically slow pace away from you, with no chance of escape.

I find that the fish are sometimes easier to spot in 3rd person mode. Keep in mind that they will be somewhere around the point indicated on the map, but they do swim around so they might not be on that exact spot.

And yes, like some already indicated, if you have taken the skill to see animals with inspector mode (default left alt), they are a lot easier to find.