California Code, Fish and Game Code - FGC § 9015

(a) Subject to Article 18 (commencing with Section 8590) of Chapter 2, prawns or shrimp, as defined in Section 8590, may be taken with prawn traps or shrimp traps under a general trap permit issued pursuant to Section 9001.

(b) A prawn trap or a shrimp trap shall be six feet or less in its greatest dimension.  Every opening from the exterior to the interior of a prawn trap or a shrimp trap shall be five inches or less in any dimension.