Yes, I believe that it's in the very core of their being to head upstream even if they never have, even if the parent fish never have.
Já, ég trúi ūví ađ ūađ sé innprentađ í ūá ađ synda á mķti straumnum... ūķtt ūeir hafi aldrei gert ūađ og ekki heldur foreldrar ūeirra.