To the southwest of Vallentine is a small pool of water that juts our from the river. It’s next to the large bridge with the roof and a small dry gulley underneath it.
If you pull out your fishing rod and unequip it a bunch of fish will spawn in the pool.
Using a varmin rifle you can shoot the fish and clear the pool in about 10 mins. 20 can spawn in there easily and they often beach themselves which means you can just pick them up on the shore.
The resulting two star fish sell for the same as a three star fish.
The real money maker is the Sockeye Samon which will make you $45 a stack.
If you get to 10 of any one fish start shooting them twice to make them 1 Star and a separate stackable.
You can sell at strawberry or valentine as they are equidistant from the spot.
To refresh the pool you have to travel a decent distance away and then come back. I usually clear the pool twice before selling my wares.
There are rabbits along the trails worth a lot if you use the varmit rifle as well.
I made $500 in one night doing this easily with no pressure or rushing.
Enjoy.