Jacana tuna fish landing. Tuna is graded A, B or C after it has been weighed and sold according to the quality of the fish. Most of the tuna handline boats operating out of Puerto Princesa are small vessels with 3 to 6 crew members. They stay out for 3 nights to their fishing grounds fishing for large tuna mainly at night. Larger vessels can stay out for up to a week. Fishing is conducted on tuna schools within one nautical mile of anchored fish attracting devices that is set in at least 1,000 m of water.