Crossword clue: a small red worm or larva, used as bait for small fresh-water fish; -- so called from its red color.
1 answer found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).
Possible answers
A young salmon or parr, in the stage in which it has transverse black bands, as if burned by a gridiron.