Purse seiners
Characteristics
| Deck TypeDecked vesselsOverviewThese vessels comprise a large group appearing in all sizes ranging from small boat to open ocean going vessels. Purse seiners are the most important and most effective vessels to catch aggregating species near the surface. The vessel surrounds the shoal with a deep curtain of netting and then the bottom of the net is pursed (closed) underneath the shoal by hauling a wire which runs from the vessel through rings on the bottom of the net and back to the vessel. Searching for shoals and assessing the size and direction of movement of it are the most important part of the fishing operation. To assist in fish detection, sometimes crows nests are arranged on masts and on large vessels observation towers and helicopter landing decks are provided.Vessel ClassLengthnormally > 15 meters (LOA)Powernormally > 90 HpTonnagenormally > 30 GT (GRT in register tons)Deck ArrangementFrom the point of view of deck arrangement three main types of one boat purse seiners can be distinguished: the American seiners (Fig. 1), the European seiners (Fig. 2) and the Drum seiners (Fig. 3).Catch Handling and Processing EquipmentAll.EquipmentDeck EquipmentTypical equipment of purse seiners consists usually of a power block or triple roller (triplex) and storage equipment for hauling and stowing the net aboard. On larger vessels the fish is pumped on board while on smaller vessels the use of brailers is more common. On boats using small seine nets all operations are generally performed by hand.Fish Detection EquipmentOn the more advanced purse seiners electronic equipment such as different types of echosounders and sonar, and track plotters are used to: support the search for schools; assess the size and movement of the school; and to keep in touch with the school whilst surrounding it with the seine.Fishing Gear Purse seines. Source: http://www.fao.org/ |
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