(a) Trawl vessel gear restrictions—(1) Minimum mesh size. No owner or operator of an otter trawl vessel that is issued a scup moratorium permit may possess more than 1,000 lb (454 kg) of scup from October 1 through April 14, more than 2,000 lb (907 kg) from April 15 through June 15, or more than 200 lb (91 kg) of scup from June 16 through September 30, unless fishing with nets that have a minimum mesh size of 5.0-inch (12.7-cm) diamond mesh, applied throughout the codend for at least 75 continuous meshes forward of the terminus of the net, and all other nets are stowed and not available for immediate use as defined in § 648.2.

(2) Mesh-size measurement. Mesh sizes will be measured according to the procedure specified in § 648.108(a)(2).

(3) Net modification. The owner or operator of a fishing vessel subject to the minimum mesh requirements in § 648.124 and paragraph (a)(1) of this section shall not use any device, gear, or material, including, but not limited to, nets, net strengtheners, ropes, lines, or chafing gear, on the top of the regulated portion of a trawl net. However, one splitting strap and one bull rope (if present), consisting of line or rope no more than 3 inches (7.2 cm) in diameter, may be used if such splitting strap and/or bull rope does not constrict in any manner the top of the regulated portion of the net, and one rope no greater that 0.75 inches (1.9 cm) in diameter extending the length of the net from the belly to the terminus of the codend along the top, bottom, and each side of the net. “Top of the regulated portion of the net” means the 50 percent of the entire regulated portion of the net that (in a hypothetical situation) will not be in contact with the ocean bottom during a tow if the regulated portion of the net were laid flat on the ocean floor. For the purpose of this paragraph (a)(3), head ropes are not considered part of the top of the regulated portion of a trawl net.

(4) Mesh obstruction or constriction. (i) The owner or operator of a fishing vessel subject to the minimum mesh restrictions in § 648.124 and in paragraph (a)(1) of this section shall not use any mesh construction, mesh configuration, or other means on, in, or attached to the top of the regulated portion of the net, as defined in paragraph (a)(3) of this section, if it obstructs or constricts the meshes of the net in any manner.

(ii) The owner or operator of a fishing vessel subject to the minimum mesh requirements in § 648.124 and in paragraph (a)(1) of this section may not use a net capable of catching scup if the bars entering or exiting the knots twist around each other.

(5) Stowage of nets. The owner or operator of an otter trawl vessel retaining 1,000 lb (454 kg) or more of scup from October 1 through April 14, 2,000 lb (907 kg) or more of scup from April 15 through June 15, or 200 lb (90.7 kg) or more of scup from June 16 through September 30, and subject to the minimum mesh requirements in paragraph (a)(1) of this section, and the owner or operator of a midwater trawl or other trawl vessel subject to the minimum size requirement in § 648.126, may not have available for immediate use any net, or any piece of net, not meeting the minimum mesh size requirement, or mesh that is rigged in a manner that is inconsistent with the minimum mesh size. A net that is stowed and not available for immediate use as defined in § 648.2, and that can be shown not to have been in recent use, is considered to be not available for immediate use.

(6) Roller gear. The owner or operator of an otter trawl vessel issued a moratorium permit pursuant to § 648.4(a)(6) shall not use roller rig trawl gear equipped with rollers greater than 18 inches (45.7 cm) in diameter.

(7) Procedures for changes. The minimum net mesh and the threshold catch level at which it is required set forth in paragraph (a)(1) of this section, and the maximum roller diameter set forth in paragraph (a)(6) of this section, may be changed following the procedures in § 648.122.

(b) Pot and trap gear restrictions. Owners or operators of vessels subject to this part must fish with scup pots or traps that comply with the following:

(1) Degradable hinges. A scup pot or trap must have degradable hinges and fasteners made of one of the following degradable materials:

(i) Untreated hemp, jute, or cotton string of 3/16 inches (4.8 mm) diameter or smaller;

(ii) Magnesium alloy, timed float releases (pop-up devices) or similar magnesium alloy fasteners; or

(iii) Ungalvanized or uncoated iron wire of 0.094 inches (2.4 mm) diameter or smaller.

(iv) The use of a single non-degradable retention device designed to prevent loss of the ghost panel after the degradable materials have failed is permitted provided the device does not impair the egress design function of the ghost panel by obstructing the opening or by preventing the panel from opening at such time that the degradable fasteners have completely deteriorated.

(2) Escape vents. (i) All scup pots or traps that have a circular escape vent with a minimum of 3.1 inches (7.9 cm) in diameter, or a square escape vent with a minimum of 2.25 inches (5.7 cm) for each side, or an equivalent rectangular escape vent.

(ii) The minimum escape vent size set forth in paragraph (b)(2)(i) of this section may be revised following the procedures in § 648.122.

(3) Pot and trap identification. Pots or traps used in fishing for scup must be marked with a code of identification that may be the number assigned by the Regional Administrator and/or the identification marking as required by the vessel's home port state.