follow Dictionary.com
They are anadromous fishes of which little more can be said than that a specimen might take a bottom bait once in a way.
The migratory fishes fall into two groups, the anadromous and the catadtomous.
of fish, "ascending a river to spawn" (as salmon do), 1753, from Latinized form of Greek anadromos "running upward," from ana "up, back" (see ana-) + dramein "to run" (see dromedary).