Assessment of the current status of exploitation and preservation of diamondback squid (Thysanoteuthis rhombus) in Vietnam
Abstract
The research results determined that the total number of vessels unintentionally capture diamondback squid in the three fisheries: stick held falling net, purpleback squid hand line and ocean tuna hand line is 3,697; Basic parameters of fishing gear are as follows: main line length from 120 - 160m, branch line length from 5 - 6m, number of hooks from 1 - 2 hooks/branch, each branch line is equipped with 01 blue or seven-color wireless LED light; fishing grounds often encounter diamondback squid from 10 - 18 degrees North latitude and from 110 - 118 degrees East longitude, especially the area around Hoang Sa and Truong Sa archipelagos; diamondback squid fishing season achieves high productivity from February to July of the solar calendar, in which the time with the highest productivity is from March to May; fishing productivity of stick held falling net, ocean tuna hand line and purpleback squid hand line is 2.5 kg/day/vessel, 2.3 kg/day/vessel and 1.9 kg/day/vessel respectively; revenue from diamondback squid of purpleback squid hand line is about 30.24 million VND/ship/year, ocean tuna hand line is about 15.15 million VND/ship/year and stick held falling net is 12.61 million VND/ship/year; diamondback squid after being brought onto the ship is usually processed by removing the internal organs (for squid >1 kg/ squid) or leaving the squid whole (for squid <1 kg/ squid) then put in a sealed plastic bag or dried and preserved with ice; diamondback squid is consumed domestically and initially exported to China (through unofficial channels) and Korea.
