California Code, Fish and Game Code - FGC § 8210.2

Except as modified by the director pursuant to Section 7652, salmon may be taken under authority of a commercial fishing license and a commercial fishing salmon stamp only in Districts 6, 7, 10, 11, 16, 17, 18, and 19.  All species of salmon, except silver salmon, may be taken only between April 15 and September 30.  Silver salmon may be taken only between May 15 and September 30.  No king salmon may be possessed that is less than 26 inches in length and no silver salmon may be possessed that is less than 22 inches.  The length of salmon is to be measured from the tip of the snout to the extreme tip of the tail without resorting to any force other than swinging or fanning the tail.  Salmon may be taken for commercial purposes only by hook and line and there is no bag limit.