California Code, Fish and Game Code - FGC § 9011

(a)(1) Subject to Article 6 (commencing with Section 8275) of Chapter 2, Dungeness crab, as defined in Section 8275, may be taken with Dungeness crab traps.

(2) A Dungeness crab trap may have any number of openings of any size. However, every Dungeness crab trap shall have at least two rigid circular openings of not less than 4 1/4 inches, inside diameter, on the top or side of the trap. If both of the openings are located on the side of the trap, at least one of the openings shall be located so that at least one-half of the opening is in the upper half of the trap.

(3) Subject to Article 6 (commencing with Section 8275) of Chapter 2, rock crab may be taken incidentally with a Dungeness crab trap used pursuant to this subdivision to take Dungeness crab, provided that the incidental taking occurs only during the season when it is lawful to take both species. A rock crab, taken incidentally with a Dungeness crab trap, that does not comply with Article 6 (commencing with Section 8275) of Chapter 2, shall be immediately returned to the waters from which it was taken.

(b)(1) Subject to Article 6 (commencing with Section 8275) of Chapter 2, rock crab, as defined in Section 8275, may be taken with rock crab traps.

(2) A rock crab trap may have any number of openings of any size. However, a rock crab trap constructed of wire mesh with an inside mesh measurement of not less than 1 7/8 inches by 3 7/8 inches, with the 3 7/8 inch measurement parallel to the floor, shall have at least one rigid circular opening of not less than 3 1/4 inches, inside diameter, located on any outside wall of the rearmost chamber of the crab trap and shall be located so that at least one-half of the opening is in the upper half of the trap. Rock crab traps constructed of other material shall have at least two rigid circular openings of not less than 3 1/4 inches, inside diameter, on the top or side of the rearmost chamber of the trap. If both of the openings are located on the side of the trap, at least one of the openings shall be located so that at least one-half of the opening is in the upper half of the trap. No rigid circular opening, as required, shall extend more than 1/2 inch beyond the plane of the wall side or top of the trap in which it is located, and it shall be clearly accessible to any crab which may be in the trap.

(3) Subject to Article 6 (commencing with Section 8275) of Chapter 2, Dungeness crab may be taken incidentally with a rock crab trap used pursuant to this subdivision to take rock crab, provided that the incidental taking occurs only during the season when it is lawful to take both species. A Dungeness crab, taken incidentally with a rock crab trap, that does not comply with Article 6 (commencing with Section 8275) of Chapter 2, shall be immediately returned to the waters from which it was taken.

(4) A person shall not possess any lobster aboard a vessel while the vessel is being used pursuant to this subdivision to take rock crab.