Young fish are a term used to describe immature fish that are still growing. FRY are the smallest young fish, usually measuring less than two inches in length. PARR are slightly larger than FRY and have distinctive vertical stripes. Fingerling are larger than PARR and measure between two and six inches in length. Grilse are larger than fingerlings and measure between six and twelve inches in length. Finally, SCROD are the largest young fish, measuring more than twelve inches in length.