JPH01248497A - Fishes migration intercepting method - Google Patents
Fishes migration intercepting methodInfo
- Publication number
- JPH01248497A JPH01248497A JP63077632A JP7763288A JPH01248497A JP H01248497 A JPH01248497 A JP H01248497A JP 63077632 A JP63077632 A JP 63077632A JP 7763288 A JP7763288 A JP 7763288A JP H01248497 A JPH01248497 A JP H01248497A
- Authority
- JP
- Japan
- Prior art keywords
- fish
- electric
- areas
- electric screen
- fishes
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 241000251468 Actinopterygii Species 0.000 title claims abstract description 67
- 238000000034 method Methods 0.000 title claims description 10
- 238000013508 migration Methods 0.000 title 1
- 230000005012 migration Effects 0.000 title 1
- 230000009182 swimming Effects 0.000 claims description 17
- 239000013535 sea water Substances 0.000 claims description 10
- 230000015572 biosynthetic process Effects 0.000 claims description 8
- 230000000903 blocking effect Effects 0.000 claims description 6
- 230000005684 electric field Effects 0.000 claims description 4
- 238000013459 approach Methods 0.000 abstract description 5
- 238000009395 breeding Methods 0.000 abstract 2
- 230000001488 breeding effect Effects 0.000 abstract 2
- 238000001514 detection method Methods 0.000 description 25
- 230000000694 effects Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 238000009360 aquaculture Methods 0.000 description 2
- 244000144974 aquaculture Species 0.000 description 2
- 238000012423 maintenance Methods 0.000 description 2
- 230000004888 barrier function Effects 0.000 description 1
- 230000000638 stimulation Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Farming Of Fish And Shellfish (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、海洋牧場において養殖を行う場合に、遊泳遮
断部に形成した電気スクリーンにより魚類の遊泳を遮断
する魚類の遊泳遮断方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for blocking fish swimming by using an electric screen formed in a swimming blocking section when cultivating fish at a marine farm.
従来、海洋牧場において大規模養殖を行う場合、養殖魚
の海洋牧場からの脱出を防止するために、様々な手法が
採られており、最も一般的には、網を用いる手法がある
が、これは網目体が風浪によって損傷し易く、網の保守
、維持Ｇこ多大な労力と費用とを要するため、最近では
網を用いることなく、魚類に対する威嚇効果を利用する
手法が考えられている。Conventionally, when carrying out large-scale aquaculture at marine farms, various methods have been used to prevent farmed fish from escaping from the marine farm.The most common method is to use nets, but this method Since the mesh body is easily damaged by wind and waves, and the maintenance and maintenance of the net requires a great deal of labor and expense, recently, methods have been considered that utilize a threatening effect on fish without using a net.
その１例として、本件出願人が提案した電気スクリーン
（こよる手法があり、これは水中に複数の電極列を配列
し、これらの各電極列に電気スクリーン発生用の電源に
より電位を与え、各電極列間に所定電界強度の電気スク
リーンを形成し、該電気スクリーンに侵入した魚類に対
し、電気スクリーンによる電気的刺激を与えて魚類を威
嚇し、魚類の遊泳を遮断するというものである。（特願
昭６１−１２６７７号出願明細書及び図面参照）
〔発明が解決しようとする課題〕
ところが、海水の抵抗率が２０〜３０Ωσと低いため、
前記電気スクリーンの形成の際に大電流を必要とし、消
費電力が非常ｌこ大きくなり、たとえば水深２ｍの海域
に数１０ｍの電気スクリーンを形成するには、数１００
ＫＶＡの電力を要し、このような電気スクリーンを常
時形成する場合、その消費電力量は極めて大きくなり、
コストも高くなるという問題点がある。One example of this is the electric screen method proposed by the applicant, in which multiple electrode rows are arranged in water, each electrode row is given a potential by a power source for generating an electric screen, and each An electric screen with a predetermined electric field strength is formed between electrode rows, and the electric screen applies electrical stimulation to fish that have entered the electric screen to intimidate the fish and prevent them from swimming. ( (See specification and drawings of Japanese Patent Application No. 61-12677) [Problem to be solved by the invention] However, since the resistivity of seawater is as low as 20 to 30 Ωσ,
When forming the electric screen, a large current is required, and the power consumption is extremely large.
If an electric screen like this requires KVA power and is constantly formed, the power consumption will be extremely large.
There is a problem that the cost is also high.
そこで、本発明は前記の点に留意してなされ、魚類の遊
泳を確実に遮断するとともに、消費電力を低減して低コ
スト化を図ることを目的とする。Therefore, the present invention has been made with the above-mentioned points in mind, and an object of the present invention is to reliably block the swimming of fish and to reduce power consumption and cost.
つぎに、前記目的を達成するための手段を、実施例に対
応する第１図を用いて説明する。Next, means for achieving the above object will be explained using FIG. 1 corresponding to an embodiment.
すなわち、海洋牧場ｆｉ＋の遊泳遮断部（２）の海水中
に複数の電極列を並行に配列し、前記各電極列間に所定
電界強度の電気スクリーンを形成し、前記電気スクリー
ンにより、魚類の遊泳を遮断する魚類の遊泳遮断方法に
おいて、本発明では、前記電気スクリーンの形成領域を
２分割し、前記画形成領域それぞれの海洋牧場（１）側
に近接′した魚群検知領域（６ａ）、（６ｂ）への魚類
の侵入を検知する２個の魚群検知器（７ａ）、（７ｂ）
のセンサ部を海水中に設け、
前記両魚群検知器（７ａ）、（７ｂ）それぞれによる魚
類の検知時に、それぞれの電気スクリーン（４ａ）、（
４ｂ）を形成するという技術的手段を講じている。That is, a plurality of electrode rows are arranged in parallel in the seawater of the swimming cutoff section (2) of the marine farm fi+, and an electric screen with a predetermined electric field strength is formed between each electrode row, and the electric screen prevents fish from swimming. In the present invention, the electric screen formation area is divided into two, and fish school detection areas (6a) and (6b) are located close to the marine farm (1) side of each of the image formation areas. ) Two fish school detectors (7a) and (7b) that detect fish intrusion
A sensor section is provided in the seawater, and when the fish school detectors (7a) and (7b) detect fish, the electric screens (4a) and (7b) are activated.
4b).
したがって、本発明によると、海洋牧場ｆｌｌ内の魚類
が両電気スクリーン（４ａ）、（４ｂ）の形成領域に接
近し、魚群検知領域（６ａ）、（６ｂ）に侵入したとき
に、魚群検知器（７ａ）、（７ｂ）それぞれにより魚群
が検知されてそれぞれ電気スクリーン（４ａ）、（４ｂ
）が形成されるため、電気スクリーンが従来のように常
時形成されるのではなく、必要時にだけ電気スクリーン
（４ａ）又は（４ｂ）が形成されることになり、常時形
成する場合に比べ、消費電力が大幅に低減され、低コス
ト化が図れる。Therefore, according to the present invention, when fish in the marine farm full approach the formation areas of both electric screens (4a) and (4b) and enter the fish school detection areas (6a) and (6b), the fish school detector Schools of fish are detected by (7a) and (7b), respectively, and electric screens (4a) and (4b) are detected, respectively.
) is formed, the electric screen (4a) or (4b) is formed only when necessary, instead of being formed all the time as in the past, and the consumption is lower than when it is formed all the time. Power consumption is significantly reduced and costs can be reduced.
つぎに、本発明を、その実施例を示した図面とともに詳
細に説明する。Next, the present invention will be described in detail with reference to drawings showing embodiments thereof.
まず、実施例１を示した％１図ないし第３図について説
明する。First, Figures 1 to 3 showing Example 1 will be explained.
全体の構成を模式的に表わした第１図において、ｉｌｌ
は入り江などに形成された海洋牧場、（２）は海洋牧場
ｆｌ） 、！：外海（３）との境界の遊泳遮断部、（４
ａ）、（４ｂ）は遊泳遮断部（２）に形成される所定電
界強度の２個の電気スクリーンであり、遊泳遮断部（２
）の海水中に、遊泳遮断部（２］の長手方向への電極列
（図示せず）が複数並行に配列され、これらの各電極列
が、遊泳遮断部（２）の長手方向のほぼ中央部において
電気的に２組に分割され、前記両組それぞれの各電極列
に、後述の２個の電源それぞれにより電位が与えられ、
前記両組それぞれの各電極列間に電気ヌクリーン（４ａ
）、（４ｂ）がそれぞれ形成される。In FIG. 1, which schematically represents the entire configuration, ill
is a marine ranch formed in an inlet, (2) is a marine ranch fl),! : Swimming barrier at the border with the open sea (3), (4
a) and (4b) are two electric screens with a predetermined electric field strength formed in the swimming blocking part (2);
), a plurality of electrode rows (not shown) are arranged in parallel in the longitudinal direction of the swimming cutoff section (2), and each of these electrode rows is located approximately in the longitudinal center of the swimming cutoff section (2). electrically divided into two groups in the section, and a potential is applied to each electrode row of each of the two groups by two power sources described later,
An electric null cleaner (4a
) and (4b) are formed, respectively.
（５ａ）、（５ｂ）は前記両組それぞれの各電極列に電
位を与える２個の電源、（６ａ）、（６ｂ）は両電気ヌ
クリーン（４ａ）ｐ （４ｂ）の形成領域の海洋牧場（
１）側にそれぞれ近接した２個の魚群検知領域、（７ａ
）、（７ｂ）は２個の魚群検知器であり、海水中に設け
られたセンサ部である超音波の送受波部及び検知部から
なり、両検知器（７ａ）、（７ｂ）により、それぞれ両
魚群検知領域（６ａ）、（６ｂ）への魚類の侵入が検知
される。(5a) and (5b) are two power supplies that apply potential to each electrode row of both sets, and (6a) and (6b) are marine pastures (4a) and (4b) in the formation area of both electric nuclei (4a) and (4b), respectively.
1) Two fish school detection areas close to each other, (7a
) and (7b) are two fish school detectors, which consist of an ultrasonic transmitting/receiving part and a detection part, which are sensor parts installed in seawater. Intrusion of fish into both fish school detection areas (6a) and (6b) is detected.
このとき、両魚群検知器（７ａ）、（７ｂ）のセンサ部
である送受波部（Ｓａ）ｊ（Ｓｂ）は、第１図及び第２
図に示すように、両魚群検知領域（６ａ）、（６ｂ）の
海水中に設けられ、第１図、第２図中の破線に示すよう
に、送受波部（Ｓａ）、（Ｓｂ）により、超音波が放射
されるとともに９反射波が受波され、受波信号がそれぞ
れ前記検知部から出力され、該検知部では、入力される
受波信号と、ノイズレベルよりやや高い基準信号とが比
較され、前記受波信号が前記基準信号を上回るときに、
検知信号が出力されるようになっている。At this time, the wave transmitting/receiving sections (Sa)j (Sb), which are the sensor sections of both fish school detectors (7a) and (7b), are
As shown in the figure, both fish school detection areas (6a) and (6b) are provided in the seawater, and as shown by the broken lines in Figures 1 and 2, the wave transmitting and receiving parts (Sa) and (Sb) , the ultrasonic wave is emitted and nine reflected waves are received, and each of the received signals is output from the detection section, and the detection section distinguishes between the input received signal and a reference signal slightly higher than the noise level. and when the received signal exceeds the reference signal,
A detection signal is output.
ところで、このように両魚群検知器（７ａ）、（７ｂ）
の送受波部（Ｓａ）、（Ｓｂ）を海水中に配設すると、
海面上から検知を行なう場合よりも検知エリアを広くす
ることができ、対象となる魚群検知領域（６ａ）、（６
１））がかなり広くても、魚類の侵入を精度よく検知で
きる。By the way, like this, both fish school detectors (7a) and (7b)
When the wave transmitting/receiving parts (Sa) and (Sb) are placed in seawater,
The detection area can be made wider than when detection is performed from above the sea surface, and the target fish school detection areas (6a), (6)
1) Even if the area is quite wide, the intrusion of fish can be detected with high accuracy.
さらに、第１図において、（８）は制御部であり、両魚
群検知器（７ａ）、（７ｂ）それぞれによる両魚群検知
領域（６ａ）、（６ｂ）への侵入魚類の検知時に、制御
部（８）により両型源（５ａ）、（５ｂ）がそれぞれ駆
動投入され、電気スクリーン（４ａ）、（４ｂ）がそれ
ぞれ形成される。Furthermore, in FIG. 1, (8) is a control unit, and when detecting fish intruding into both fish school detection areas (6a) and (6b) by both fish school detectors (7a) and (7b), the control unit By (8), both mold sources (5a) and (5b) are driven and turned on, respectively, to form electric screens (4a) and (4b), respectively.
つぎに、前記実施例の動作について説明する。Next, the operation of the above embodiment will be explained.
いま、両魚群検知器（７ａ）、（７ｂ）により、両魚群
検知領域（６ａ）、（６ｂ）の探知が行われ、たとえば
第３図（ａ）に示すような受波信号が一方の魚群検知器
（７ａ）の送受波部（Ｓａ知）ら検知部に入力されると
、前記検知部により、入力された受波信号と、第３図（
ａ）中に示すレベルＶｅの基準信号とが比較され、前者
の受波信号が後者の基準信号を上回るときに、−方の魚
群検知領域（６ａ）に海洋牧場（１）内の魚類が侵入し
たとして、一方の魚群検知器（７ａ）から検知信号が出
力される。Now, both fish school detectors (7a) and (7b) are detecting both fish school detection areas (6a) and (6b), and for example, a received signal as shown in Fig. 3(a) is detected when one fish school is detected. When the signal is input to the detection section from the wave transmitting/receiving section (Sa) of the detector (7a), the input reception signal and the signal shown in FIG.
a) The level Ve reference signal shown in the figure is compared, and when the former received signal exceeds the latter reference signal, fish in the marine farm (1) have invaded the - side fish detection area (6a). Then, a detection signal is output from one of the fish school detectors (7a).
そして、一方の魚群検知器（７ａ）からの検知信号に基
づき、第３図（ｂ）に示すように、制御部（８）により
一方の電源（５ａ）が駆動投入され、一方の魚群検知器
（７ａ）から検知信号が出力されたときに、海洋牧場＋
１１内の魚類が一方の電気スクリーン（４ａ）の形成領
域に接近したとして、電源（５ａ）が投入されて電気ス
クリーン（４ａ）が形成される。Then, based on the detection signal from one of the fish school detectors (7a), as shown in FIG. (7a) When the detection signal is output from Ocean Farm +
When the fish in the screen 11 approaches the forming area of one electric screen (4a), the power source (5a) is turned on and the electric screen (4a) is formed.
なお、他方の魚群検知領域（６ｂ） ｆこ海洋牧場＋Ｉ
ｌ内の魚類が侵入した場合も、同様にして、他方の魚群
検知器（７ｂ）から検知信号が出力され、この検知信号
に基づき、制御部（８）により他方の電源（５ｂ）が駆
動投入されて電気スクリーン（４ｂ）が同様に形成され
る。In addition, the other fish school detection area (6b)
Similarly, when fish enter the area, a detection signal is output from the other fish detector (7b), and based on this detection signal, the control unit (8) turns on the other power source (5b). An electrical screen (4b) is similarly formed.
したがって、前記実施例１によると、電気スクリーンが
常時形成されるのではなく、海洋牧場（１）内の魚類が
両電気スクリーン（４ａ）、（４ｂ）の形成領域それぞ
れ（こ接近したときのみ、両電気スクリーン（４ａ）、
（４ｂ）が形成されるため、必要時にだけ電気スクリー
ン（４１）又は（４ｂ）が形成されることになり、常時
形成する場合に比べ、消費電力を大幅に低減することが
でき、低コスト化を図ることができる。Therefore, according to the first embodiment, the electric screen is not formed all the time, but only when the fish in the marine farm (1) approach the forming areas of both the electric screens (4a) and (4b). Both electric screens (4a),
(4b) is formed, the electric screen (41) or (4b) is formed only when necessary, and compared to the case where it is formed all the time, power consumption can be significantly reduced and costs can be reduced. can be achieved.
つぎに、実施例２を示した第４図について説明する。Next, FIG. 4 showing the second embodiment will be explained.
第４図において、第１図と同一記号は同一もしくは相当
するものを示し、第１図と異なる点は、遊泳遮断部（２
）の海水中に並行に配列した各電極列を、３組に分割し
て電気スクリーン形成領域を３分割し、各組それぞれの
各電極列に、３個の主電源（９ａ）、（９ｂ）、（９ｃ
）それぞれにより電位を与えて電気スクリーン（１０ａ
） 、 （１０ｂ） 、 （１０ｃ）を形成するように
し、各主電源（９ａ）＝（９ｂ）、（９ｃ）に、非常時
のバックアップ用補助電源（ｌｌａ）−（ｌｌｂ）、（
ｌｌｃ）をそれぞれ並役し、制御部（１２）によりこれ
らの各電源（９ａ）〜（９Ｃ）。In Fig. 4, the same symbols as in Fig. 1 indicate the same or equivalent parts.
) are arranged in parallel in seawater, and are divided into three sets to divide the electric screen forming area into three, and each set of electrode rows is connected to three main power supplies (9a), (9b). , (9c
) by applying a potential to each electric screen (10a
), (10b), (10c), and each main power supply (9a) = (9b), (9c) is connected to an emergency backup auxiliary power supply (lla) - (llb), (
llc), and the control unit (12) controls these power supplies (9a) to (9C).
（ｌｌａ）〜（ｌｌｃ）を制御するようにした点である
。The point is that (lla) to (llc) are controlled.
なお、第４図には図示されていないが、前記した魚群検
知領域（６ａ）、（６ｂ）と同様、各電気スクリーン（
１０ａ）〜（’１０ ｃ ）の形成領域の海洋牧場（１
）側（こそれぞれ近接した３個の魚群検知領域が設定さ
れ、これらの各魚群検知領域への魚類の侵入を検知する
３イ剛の魚群検知器がそれぞれ海水中に設けられ、各魚
群検知器からの信号モこ基づき、制御部（１２１＋こよ
り各主電源（９ａ）〜（９Ｃ）の制御が行われるように
なっている。Although not shown in FIG. 4, each electric screen (
10a) to ('10c) formation area marine ranch (1
) side (three fish school detection areas that are close to each other are set, and three fish school detectors are installed in the seawater to detect the intrusion of fish into each of these fish school detection areas, and each fish school detector Each main power source (9a) to (9C) is controlled by the control unit (121+) based on the signal from the main power source (9a) to (9C).
したがって、前記実施例２によると、３個の電気スクリ
ーン（１０ａ）〜（１０ｃ）の形成領域に分割したため
、前記した実施例１の場合よりもさらに消費電力乏・節
減することができ、主電源（９ａ）〜（９Ｃ）及び補助
電源（ｌｌａ）〜（ｌｌｃ）が小容量のもので済む。Therefore, according to the second embodiment, since the formation area is divided into three electric screens (10a) to (10c), power consumption can be further reduced than in the first embodiment, and the main power supply (9a) to (9C) and auxiliary power supplies (lla) to (llc) need only have small capacities.
また、補助電源（ｌｌａ）〜（ＩＩＣ）により、非常時
のバックアップが可能となる。Furthermore, the auxiliary power supplies (lla) to (IIC) enable backup in case of an emergency.
なお、電気スクリーンの形成領域を４個以上に分割して
もよいのは勿論である。It goes without saying that the area in which the electric screen is formed may be divided into four or more areas.
本発明は、以上説明したように構成されているので、以
下に記載する効果を奏する。Since the present invention is configured as described above, it produces the effects described below.
電気スクリーンにより魚類の遊泳を確実に遮断すること
ができるのは勿論のこと、従来のように゛電気スクリー
ンを常時形成するのではなく、各魚群検知器により、各
電気スクリーンの形成領域それぞれへの魚類の接近が検
知されたときのみ、各電気スクリーンをそれぞれ形成す
るため、常時形成する場合に比べ、消費電力を大幅に低
減することができ、低コスト化を図ることが可能となり
、海洋牧場における養殖に極めて有効である。It goes without saying that electric screens can reliably block fish from swimming, but instead of forming electric screens all the time like in the past, each school of fish detector can be used to control the area where each electric screen is formed. Since each electric screen is formed only when the approach of fish is detected, it is possible to significantly reduce power consumption and reduce costs compared to the case where they are formed all the time. Extremely effective for aquaculture.
図面は、本発明の魚類の遊泳遮断方法の実施例を示し、
第１図ないし第３図は実施例１を示し、第１図は模式図
、第２図は一部の正面図、第３図（ａ） 、 （ｂ）は
動作説明用の各種信号波形図、第４Ａ施例２の模式図で
ある。
ｆｉ＋−・・海洋牧場、＋２１ ・・・遊泳遮断部、（
４ａ）、（４ｂ）、（１０ａ）〜（１０ｃ）・・・電気
スクリーン、（６ａ）、（６ｂ）・・・魚群検知領域、
（７ａ）、（７ｂ）・・・魚群検知器。The drawings show an example of the method for blocking fish swimming of the present invention,
1 to 3 show the first embodiment, FIG. 1 is a schematic diagram, FIG. 2 is a partial front view, and FIGS. 3(a) and 3(b) are various signal waveform diagrams for explaining operation. , FIG. 4A is a schematic diagram of Example 2. fi+-...Ocean farm, +21...Swimming block, (
4a), (4b), (10a) to (10c)...electric screen, (6a), (6b)...fish school detection area,
(7a), (7b)... Fish school detector.
Claims (1)
並行に配列し、前記各電極列間に所定電界強度の電気ス
クリーンを形成し、前記電気スクリーンにより、魚類の
遊泳を遮断する魚類の遊泳遮断方法において、 前記電気スクリーンの形成領域を複数に分割し、前記各
形成領域それぞれの海洋牧場側に近接した領域への魚類
の侵入を検知する複数個の魚群検知器を海水中に設け、 前記各魚群検知器それぞれによる魚類の検知時に、それ
ぞれの電気スクリーンを形成することを特徴とする魚類
の遊泳遮断方法。(1) A plurality of electrode rows are arranged in parallel in the seawater at a swimming cutoff part of the marine farm, and an electric screen with a predetermined electric field strength is formed between each electrode row, and the electric screen blocks swimming of fish. In the method for blocking the swimming of fish, the formation area of the electric screen is divided into a plurality of areas, and a plurality of fish school detectors are installed in the seawater to detect the intrusion of fish into areas close to the marine farm side of each of the formation areas. A method for blocking swimming of fish, comprising: forming respective electric screens when each of the fish school detectors detects fish.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63077632A JPH01248497A (en) | 1988-03-29 | 1988-03-29 | Fishes migration intercepting method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63077632A JPH01248497A (en) | 1988-03-29 | 1988-03-29 | Fishes migration intercepting method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01248497A true JPH01248497A (en) | 1989-10-04 |
| JPH0578291B2 JPH0578291B2 (en) | 1993-10-28 |
Family
ID=13639276
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63077632A Granted JPH01248497A (en) | 1988-03-29 | 1988-03-29 | Fishes migration intercepting method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01248497A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5327854A (en) * | 1992-07-31 | 1994-07-12 | Smith-Root, Inc. | Electric fish shocking devices using programmable output waveforms |
| US5460123A (en) * | 1993-04-23 | 1995-10-24 | The United States Of America As Represented By The Secretary Of Agriculture | Electroshock repulsion of waterfowl, aquatic animals, and small mammals |
-
1988
- 1988-03-29 JP JP63077632A patent/JPH01248497A/en active Granted
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5327854A (en) * | 1992-07-31 | 1994-07-12 | Smith-Root, Inc. | Electric fish shocking devices using programmable output waveforms |
| US5460123A (en) * | 1993-04-23 | 1995-10-24 | The United States Of America As Represented By The Secretary Of Agriculture | Electroshock repulsion of waterfowl, aquatic animals, and small mammals |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0578291B2 (en) | 1993-10-28 |
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