|
A cast net, also called a throw net, is a net used for fishing. It is a circular net with small weights distributed around its edge. The net is cast or thrown by hand in such a manner that it spreads out on the water and sinks. This technique is called net casting or net throwing. Fish are caught as the net is hauled back in.〔Dunbar〕 This simple device is particularly effective for catching small bait or forage fish, and has been in use, with various modifications, for thousands of years. On the US Gulf Coast, it is used especially to catch mullet, which will not bite a baited hook. == Construction and technique == Contemporary cast nets have a radius which ranges from 4 to 12 feet (1.2 to 3.6 metres). Only strong people can lift the larger nets once they are filled with fish. Standard nets for recreational fishing have a four foot hoop. Weights are usually distributed around the edge at about one pound per foot (1.5 kilograms per metre). Attached to the net is a handline, one end of which is held in the hand as the net is thrown. When the net is full, a retrieval clamp, which works like a wringer on a mop, closes the net around the fish. The net is then retrieved by pulling on this handline. The net is lifted into a bucket and the clamp is released, dumping the caught fish into the bucket.〔Burnley, pp 63–64.〕 Cast nets work best in water no deeper than their radius. Casting is best done in waters free of obstructions. Reeds cause tangles and branches can rip nets. The net caster may choose to stand with one hand holding the handline, and with the net draped over the other arm so that the weights dangle, or, with most of the net being held in one hand and only a part of the lead line held in the other hand so the weights dangle in a staggered fashion (approximately half of the weights in the throwing hand being held higher than the rest of the weights). The line is then thrown out to the water, using both hands, in a circular motion rather as in hammer throwing. The net can be cast from a boat, or from the shore, or by wading.〔 There are also optional net throwers that can make casting easier. These look like a lid from a trash can, including the handle on top. The outside circumference has a deep gutter. The net is loaded along the gutter and the weights are placed inside the gutter. The net is then tossed into the water using the thrower. File:BarradaLagoa canal fishersman.png|Net casting in Fisher at Barra da Lagoa, Florianópolis, Brazil File:A fisherman casting a net.jpg|Fishing with a cast net. File:Lac S%C3%A9lingu%C3%A92.jpg|Fishermen casting nets on Lake Sélingué. File:Normal Atos-7-059.jpg|Fishing with cast net from a boat in Magra River, Italy File:Tank fishing near Unnichai, Batticaloa.JPG|Cast net uses in pond, Sri Lanka. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「cast net」の詳細全文を読む スポンサード リンク
|