Net - Ami

A net made of woven threads or other fibers for the purpose of capturing or collecting birds, animals, aquatic plants, and animals. Coarse nets made from coarse stem bark fibers have been used to make bag-shaped containers such as female divers' skari (game containers), lunch boxes, and whetstone containers. However, nets were most developed as tools for catching fish and birds. Nets used for bird catching include mist nets, which are placed over ridges where birds pass in order to catch small birds on their way to migrate, and sometimes pheasants and ducks, harikiri nets, which sag and envelop birds when they are caught, musou nets, which are quickly raised and covered when a bird approaches, sade nets, which are used to catch birds as they fly, throw nets, and thrust nets, which are used to cover birds that are hiding. Currently, mist nets and other nets are prohibited by law to protect wild birds, but their unique mechanism and the taste of wild birds have made them popular, and there is no end to the number of businesses using them.

Net fishing, along with lining, is a central fishing method. From the Middle Ages, especially towards the end of the Muromachi period, fishing methods using various nets appeared. In the Edo period, the demand for fish for fertilizer increased due to the development of cities and advances in agricultural technology, and fishing developed rapidly. Net fishing in particular developed remarkably, occupying a central position among fishing methods, and it is thought that the prototype of today's basic net fishing was almost complete. Furthermore, net fishing progressed significantly with the development of the cotton spinning industry after the Meiji period, and the appearance of lighter and stronger synthetic fibers led to the further expansion of the scale of fishing methods such as agrinets.

There are many types of fishing nets, but they can be classified as follows based on how they are used:

(1) Scooping nets: A net that is supported around the periphery by a frame and used to scoop up fish.

(2) Cover nets: These are nets that are placed over fish from above the water. A cast net is a typical example of this.

(3) Swirl nets: These are used to encircle schools of fish in the surface layer of the ocean and reel them in to the side of the boat to catch them. Purse seine and hauling net are advanced versions of this type.

(4) Seine fishing: A method of capturing a school of fish by surrounding it and pulling it to the shore or a boat. There are beach seine and boat seine, and boat seine is divided into float seine and bottom seine. The boat seine used for sardine fishing in the Uwa region of Ehime Prefecture is a type of float seine, and trawl fishing is an advanced version of bottom seine.

(5) Shiki-net fishing: A net is laid underwater and used to scoop up the schools of fish that gather on top of it.

(6) Gill nets: These are used to catch fish and other marine animals by catching them in meshes. There are floating gill nets and bottom gill nets. Drift nets, which are stretched on the ocean surface and allowed to drift with the tidal currents, also belong to this type.

(7) Fixed nets: These are used to capture schools of fish by setting nets in areas where schools of fish migrate. These are generally called fixed nets. Many of them have local names, such as Oshiki net in the Nagasaki region, Daibo net on the Pacific coast of the Tohoku region, and Yukinari net in the Hokkaido region.

[Takenori Noguchi]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

鳥獣や水産動植物などを捕獲、採集する目的で糸などの繊維を編んだもの。粗い茎皮繊維でつくった目の粗い網地は海女(あま)のスカリ（獲物入れ）や弁当入れ、砥石(といし)入れなどの袋状の容器類に用いられてきた。しかし網は魚や鳥をとる道具としてもっとも発達した。捕鳥法に用いられる網には、渡りの途中の小鳥や、ときにキジ、カモなどをとるため、鳥の通過する尾根などに渡すかすみ網、鳥がかかるとたるんで包んでしまう張切(はりきり)網、鳥が寄ってくると、速やかに引き起こしてかぶせとる無双(むそう)網、飛び立つ鳥をねらう叉手(さで)網、潜んでいる鳥にかぶせる投げ網、突き網などがある。現在、野鳥保護のためかすみ網などは法で禁じられているが、その珍しい仕掛けと野鳥の味が人気をよんで、使用する業者が跡を絶たない。

　網漁は、釣漁とともに漁法の中心をなしている。中世ことに室町末期ごろから、各種の網を使用した漁業が出現した。江戸期に入ると、都市の発達や農業技術の進展による肥料用の魚類の需要が高まり、漁業は急速に発達し、ことに網漁の発達は著しく、漁法のなかでも中心的な位置を占め、今日の基本的な網漁の祖型はほぼ出そろったと考えられる。また網漁は明治以後の綿糸紡績工業の発達によって著しく進歩し、さらに軽くて強靭(きょうじん)な化学繊維の出現は揚繰(あぐり)網などの規模をいっそう大きいものにした。

　漁網の種類は豊富であるが、使用形態から次のように分類できる。

(1)抄網(すくいあみ)類　枠で網の周囲を支え、魚類をすくい上げるもの。

(2)掩(かぶせ)網類　水上から魚類にかぶせるもの。投網はこの代表である。

(3)巻（旋）(まき)網類　おもに海の表層の魚群を囲み、船側に繰り寄せて捕獲するもの。巾着(きんちゃく)網や揚繰網はこの形の進歩したもの。

(4)引網(ひきあみ)類　魚群を包囲し、岸あるいは船に引き寄せて捕獲するもの。地引網と船引網とに分かれ、船引網には浮(うき)引網と底引網の別がある。愛媛県宇和地方で行われるイワシ船引網は浮引網の一種であり、トロール漁は底引網の進歩したもの。

(5)敷(しき)網類　水中に網を敷き、その上に集まる魚群をすくい上げるもの。

(6)刺(さし)網類　魚その他の海棲動物を網目にかけて捕獲するもの。浮刺網、底刺網の別がある。海の表層に張り、潮流に漂わせる流し網もこの類である。

(7)建(たて)網類　魚群の来遊する場所に網を定設して捕獲するもの。一般に定置(ていち)網とよばれる。長崎地方の大敷(おおしき)網、東北地方の太平洋岸の大謀(だいぼう)網、北海道地方の行成(ゆきなり)網など地方名が多い。

［野口武徳］

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