Fishing vessels shall be marked with vessel markings in accordance with Appendix 2. Any fishing vessel of 20 GT or above shall also be marked with the International Radio Call Sign (IRCS)
The IRCS of a fishing vessel is its radio call sign.
The IRCS shall be placed above the waterline on both sides of any fishing vessels and on a deck where the IRCS is not obscured by fishing gear(s), and shall be clear of the bow, stern, discharge or areas which might be prone to damage or discoloration. In case that the lowest edge of characters is under the waterline when the fish holds are full, the IRCS shall be placed on the fishing vessel’s superstructure.
Vessel markings shall be painted with marine coating. Characters and the edges thereof for the vessel name and the CT number shall maintain clear and identifiable at all times.

• Appendix 2 Specification of Width, Height and Color of Characters for Vessel Markings.pdf

Fishing gears of any tuna longline fishing vessel shall be equipped with floats, signal flags, radar reflector buoys or other similar devices so as to identify the position(s) and fishing area(s).

Before port departure, fishery operators or captains of tuna longline fishing vessels shall turn on the ALC of AIS, and shall check with the Fisheries Monitoring Center (FMC) of the Fisheries Agency, Council of Agriculture, Executive Yuan to confirm the vessel position has been transmitted. After port departure, the ALC or AIS shall be maintained functional.
The ALC shall transmit at least one vessel position every hour.
In the event that the FMC confirms that it does not receive any vessel position, the FMC shall notify the central competent authority. The central competent authority shall order the concerned vessel to return to a port within the required timeframe for repairing. Before returning to a port, the fishery operator or captain shall transmit the vessel positions to a fishery radio station once every hour through the communication equipment. After returning to a port, the concerned vessel shall not leave until the ALC or AIS has been repaired.
Fees for the services and communications of the ALC shall be borne by fishery operators. The competent authority may subsidize depending on the financial situation of the government.

In case that the identification numbers of the ALC have changed, the fishery operator shall notify the professional institution in writing.
In case that the numbers of MMSI have changed, the fishery operator shall notify the central competent authority in writing.