Surrounding Net Fishing
Purse seine is one of the most important types of fishing gear in the marine fishing sector of Vietnam . It is the fishing gear having the potential for operation in offshore areas. The marine product from the purse seine is about 20.6% of the total catch.
With the appearance of new techniques and Fish Aggregating Devices including: Using lights and fish shelters for luring fish; using nylon netting material, purse seine fishery developed very quickly. Most purse-seiners in the Northern and Central Provinces are of small size ranging 13-16 m in length with engines of less than 90 Hp. In the Southern provinces, the sizes of purse seiners are bigger and there is many of 16-23 m in length with engines of 90-450 Hp.
The purse seines are large-scale fishing gear and are used on fishing boats of 33-450 Hp, they are concentrated mainly in the Central and Southern provinces. There are few purse seines in the northern provinces . Every year about 600 purse seiners of 33-74 Hp move from the Central region to the Gulf of Tonkin to operate.
Purse seine fishery in Vietnam uses two fishing methods. These are the luring method and searching method.
The luring method: This is very popular throughout the whole country. The length of the purse seine in the luring method is usually about 250-500 m and the depth of the net is about 45-70 m. The reason for this is that the fish schools often concentrate around fish shelters and under light sources. Therefore, it doesn't need a large size of net but big enough to surrounding fish school only.
The searching method: Pelagic fish often move at high speed, so the purse seiners must also have high speed of movement and of setting the net. The purse seines must be both long and deep. Commonly the nets are 500-1200 m long and 70-120 m deep.
At present, the surrounding nets are second in marine catches of Vietnamese fisheries. Annual production of the surrounding net is about 30% of the total catch of the country. The main species of the local and commercial types of surrounding net are small pelagic fish and include: Sardine, mackerel, round scad, skipjack tuna, anchovy etc.
Fishing Gear and Methods
Based on the structure of nets and their operating methods, it is possible to divide the surrounding nets in Vietnam into the following types:
- Anchovy Purse Seine
- Luring Purse Seine
- Searching Purse Seine