JP2016192907A - White bait fishery method, and light source for white bait fishery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a white bait fishery method capable of fishing white baits which are fry efficiently with the aligned size, and with little contamination of fish which is not a fishery object, and saving power consumption at that time.SOLUTION: In a white bait fishery method, white bait-gathering light in blue to green having a maximal value in a wavelength region of 450-540 nm is radiated in the water, in the flashing state at the frequency of 10-50 Hz.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a shirasu fishing method and a shirasu fishing light source capable of efficiently collecting or traveling shirasu larvae near a light source.

In general, shirasu, an anchovy fry, has a high commercial value and is consumed in various forms, such as in a raw state, in a pot, or in dry matter. In addition, since the freshness of this shirasu tends to decrease, it is necessary to ship or process it as soon as possible after landing.
In addition, Shirasu is traded at a higher price when no other fish is mixed in and the same size. For this reason, landed shirasu is shipped after sorting by fishermen. As the time required for this sorting operation increases, the cost required for shipping increases and the freshness of the shirasu also decreases. Therefore, the shirasu of the same size as possible at the time of fishing should be reduced as much as possible without the inclusion of fish other than shirasu. However, it was desired to catch it.
2. Description of the Related Art Conventionally, a technique for collecting fish using a fish collecting lamp at night using the property that fish gather in light is known. In this technical field, with the widespread use of LEDs, it has become possible to emit light in a desired wavelength region in water.
Furthermore, as a result of various studies, it is becoming clear that a desired fish can be collected or moved around the light source by setting a desired wavelength of light emitted from the light source for fish collection.
In view of such circumstances, the inventors of the present invention have been working on the development of a technique for catching shirasu of a uniform size while minimizing the contamination of fish other than shirasu.
As prior art in the technical field related to the present invention, for example, Japanese Patent Application Laid-Open No. 2000-125698 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2008-283906 (Patent Document 2) are known.

The specification paragraph 0007 of Patent Document 1 describes that it has been found that small fish such as shirasu (sardine or sardine larvae) tend to gather better when irradiated with blue light or blue-green light than white light. .
Patent Document 2 discloses a technique of dividing a school of fish as desired by blinking light at a cycle in which the fish takes repelling action in water.

JP 2000-125698 A JP 2008-283906 A

According to the research of the inventors of the present invention, although blue light or blue-green light certainly has the effect of collecting or circulating shirasu, which is a fry, in the vicinity of the light source, not only shirasu but also adult sardine fish It was confirmed to have the effect of collecting or traveling around. Therefore, it was not possible to selectively catch shirasu only by considering the technical contents disclosed in Patent Document 1.
Furthermore, according to the technical content disclosed in Patent Document 2, although it is considered that the school of fish can be divided as desired, for example, adult sardine fish could not be selectively avoided from the fishing light.

  The present invention has been made in view of such a conventional situation, and collects or goes around a sardine fry (shirasu) in the vicinity of a light source for collecting fish, and also provides a light source for collecting adult sardines and fishes other than the target fish. It is to provide a shirasu fishing method that can be collected or moved to a position farther away from the shirasu and a shirasu fishing light source used therefor.

In order to achieve the above object, the shirasu fishing method according to the first aspect of the present invention is to flash blue-green shirasu collection light having a maximum value in the wavelength region of 450 to 540 nm in water at a frequency of 10 to 50 Hz. It is characterized by radiating.
In the first invention having the above-described configuration, by using blue to green light having a maximum value in a wavelength region of 450 to 540 nm as light for collecting shirasu, mainly sardine fry and adult fish are collected or toured around the light source. Has the effect of causing At this time, the shirasu collection light blinks at a frequency of 10 to 50 Hz, so that the larvae shirasu can be collected or traveled closer to the light source, and the light source should be avoided for adult sardine fish and fish other than sardines. Has the effect of causing

Shirasu catching method according to the second aspect of the present invention is the first aspect of the present invention, wherein in the school of fish that is collected near the light source that emits the light for collecting shirasu, or that travels around the light source, the ratio of the fry is higher than the adult fish. It is characterized by catching a large school of fish.
In the second invention of the above configuration, in addition to the same action as the first invention, in the school of fish that gathers or goes around the light source that emits the light for collecting shirasu, it is on the light source side, and the ratio of fry is higher than adult fish By catching a large school of fish, it has the effect of minimizing the contamination of adult sardines and undesired fish (mainly horse mackerel) in the catch.
As a result, it has the effect of shortening the time required for the sorting operation to remove adult sardine fish and non-target fish from the shirasu after landing.

The shirasu fishing method according to the third aspect of the invention is characterized in that, in the first or second aspect of the invention, the shirasu that is the subject of fishing is an anchovy fry.
In the third invention having the above-described configuration, the catch target in the first or second invention is specified as an anchovy fry (shirasu), and the action thereof is the same as that of the first or second invention.

A light source for shirasu fishing that is a fourth aspect of the invention includes an LED light source that emits shirasu collection light in water, and a control unit that can control at least the frequency of the shirasu collection light emitted from the LED light source. The light for collecting shirasu is blue to green having a maximum value in a wavelength region of 450 to 540 nm and blinks at a frequency of 10 to 50 Hz.
In the fourth invention having the above-described configuration, the light for collecting shirasu is blue to green having a maximum value in the wavelength region of 450 to 540 nm, so that mainly sardine fry and adult fish are collected or traveled in the vicinity of the light source. It has the action.
In addition, by flashing such shirasu light for collection at a frequency of 10 to 50 Hz, shirasu, which is a fry, is collected or moved closer to the LED light source, and for sardine adult fish and non-sardine fish It has the effect of repelling the LED light source. Further, the control unit has an effect of controlling a frequency related to blinking of the shirasu collection light emitted from the LED light source as desired.

The light source for shirasu fishing according to the fifth aspect of the invention is the fourth aspect of the invention, characterized in that the shirasu that is the target of catching is an anchovy fry.
5th invention specifies the catch object when using 4th invention to the larva of anchovy (shirasu), The effect | action is the same as 4th invention.

According to the shirasu fishing method according to the first and second inventions, it is possible to collect or circulate adult sardine fish or fish other than sardines at a position further away from the light source, while shirasu is a fry near the light source. That is, most of the fish collected or traveled to a position very close to the light source can be made shirasu.
For this reason, by selectively catching a school of fish that is closer to the light source (a school of shirasu than adult fish), the size of the shirasu is more uniform, and adult sardines and non-sardine fish Shirasu with less contamination can be obtained.
In this case, it can save a lot of time for the sorting operation to remove adult sardines and undesired fish from the caught shirasu, so it is possible to ship a high quality shirasu with higher freshness and size. it can. In other words, the economics of Shirasu fishing can be greatly improved.
In addition, according to the first and second inventions, when the shirasu is landed, adult sardine fish and unintended fish can be reduced, so that the delicate fishing net for shirasu can be produced by adult sardine fish and unintended fish. The risk of damage can be reduced. As a result, the cost for replacement and maintenance of the fishing net can be reduced.
Furthermore, since the shirasu collection light is radiated into the water as flashing light, it has the merit that the power consumption during the shirasu collection light emission can be reduced compared to the case where the shirasu collection light is emitted as continuous light. . Thereby, since the energy consumption required for fish collection can be reduced, it has the effect that the cost concerning shirasu fishing can also be reduced.
As described above, according to the shirasu fishing method according to the first and second inventions, it is possible to easily catch high-quality shirasu with less energy. As a result, the profitability of Shirasu fishing can be improved.

  In the third invention, the shirasu caught by the above-described first and second inventions is specified as an anchovy fry, and the effect is the same as the effect of the first or second invention.

The fourth invention specifies the first invention described above as a product invention.
According to the fourth aspect of the present invention, there is provided a light source for catching shirasu that can gather or travel around the LED light source while making the shirasu of the same size as small as possible mixed with adult sardine fish or fish other than shirasu. can do.
In this case, a shirasu that has a uniform size by selectively catching a school of fish in the vicinity of the LED light source according to the fourth aspect of the invention, and is less contaminated with adult sardines and undesired fish (mainly horse mackerel). Can be obtained.
As a result, the same effect as that of the first or second invention described above is exhibited.

  According to the fifth aspect of the present invention, the shirasu that gathers or travels in the vicinity thereof according to the fourth aspect of the present invention is specified as an anchovy fry, and the effect is the same as the effect of the fourth aspect.

It is a conceptual diagram of the light source for shirasu fishing which concerns on embodiment of this invention. It is a system block diagram of the light source for shirasu fishing which concerns on embodiment of this invention. It is a schematic diagram for demonstrating the shirasu fishing method which concerns on embodiment of this invention. It is a graph which shows the measurement result of the relative luminous sensitivity of anchovy. (A) It is a graph which shows the distance from the anchovy and the horse mackerel light source at the time of emitting red light (peak wavelength: 635 nm) from a light source, (b) When green light (peak wavelength: 520 nm) is emitted from a light source It is a graph which shows the distance from the light source of anchovy and a horse mackerel, (c) It is a graph which shows the distance from the light source of anchovy and a horse mackerel at the time of emitting blue light (peak wavelength: 470 nm) from a light source. (A) Temporal change in distance from the anchovy light source when red light (peak wavelength: 635 nm), green light (peak wavelength: 520 nm), and blue light (peak wavelength: 470 nm) are emitted as continuous light from the light source (B) Swimming of anchovy when red light (peak wavelength: 635 nm), green light (peak wavelength: 520 nm), and blue light (peak wavelength: 470 nm) are emitted as continuous light from the light source. It is a graph which shows a time-dependent change of speed. (A) It is a graph which shows a time-dependent change of the distance from the light source of the anchovy when green light (peak wavelength: 520 nm) is irradiated from the light source at different frequencies, and (b) green light (peak wavelength: 520 nm) from the light source. It is a graph which shows a time-dependent change of the swimming speed of the anchovy when it irradiates with changing frequency. (A) After continuously irradiating blue light with green light (peak wavelength: 500 nm) and white light (blue light: 470 nm, yellow light: 570 nm) formed by mixing blue light and yellow light while swimming FIG. 5 is a graph showing the distance from the light source of the horse mackerel at each time point when irradiating blinking light (intermittent light) with frequencies set to 1.3 Hz, 10 Hz, and 55 Hz for 20 minutes, respectively. (B) After irradiating blue-green light (peak wavelength: 500 nm) and white light mixed with blue light and yellow light (blue light: 470 nm, yellow light: 570 nm) for 30 minutes while swimming anchovy 4 is a graph showing the distance from the anchovy light source at each time point when the blinking light (intermittent light) with the frequencies set to 1.3 Hz, 10 Hz, and 55 Hz is irradiated for 20 minutes.

  A shirasu light source and a shirasu fishing method using the same according to an embodiment of the present invention will be described below with reference to FIGS.

First, the shirasu light source 1 according to the present embodiment will be described in detail with reference to FIGS.
As shown in FIG. 1, for example, as shown in FIG. 1, a cylindrical casing 3 made of a transparent material is watertightly connected to a lower end of a main body 2 made of a watertight casing. A substrate 4 that supports a number of LED light sources 5 is housed in the casing 3 in a watertight manner.
Further, a power supply line 6 is connected to the main body 2, and power for causing the LED light source 5 to emit light is supplied to the substrate 4 through the power supply line 6.
In addition, you may accommodate the board | substrate 4 which mounted LED light source 5 in the casing 3 in the state arrange | positioned in the polygonal cylinder shape in the casing 3 so that the light from the LED light source 5 can be radiated | emitted in the circumferential direction of the casing 3. Of course, if possible, the substrate 4 may be formed in a cylindrical shape.
Moreover, in the shirasu light source 1 according to the present embodiment, the shirasu collection light emitted from the LED light source 5 is blinking light. For this reason, in the shirasu light source 1 according to the present embodiment, a control unit 11 (see FIG. 2 in the subsequent stage) for controlling the frequency when the LED light source 5 blinks is stored in the main body unit 2. It may be left.

Next, a mechanism for causing the LED light source 5 to emit light in the shirasu light source 1 will be described in detail with reference to FIG.
In the shirasu light source 1 according to the present embodiment, a control unit 11 is connected to the substrate 4 that supports the LED light source 5, and further, a power source 12 for supplying power to the control unit 11 and the substrate 4 is connected. ing.
Thus, in the shirasu light source 1 according to the present embodiment, by providing the control unit 11, the frequency at which light is emitted while blinking the LED light source 5 instructed to the substrate 4 can be controlled as desired.
In addition, in the shirasu light source 1 according to the present embodiment, the control unit 11 may be provided inside the main body 2 shown in FIG. 1, or from the substrate 4 that supports the main body 2 and the LED light source 5. The frequency at which the control unit 11 is provided at a separate position (for example, a fishing boat), a line for transmitting a control signal from the control unit 11 together with the power supply line 6 is provided separately, and the LED light source 5 blinks. May be configured to be controllable as desired.
Further, although not particularly illustrated, an input operation unit and a memory may be separately provided in addition to the control unit 11 so that the control signal generated from the control unit 11 can be changed as desired on site.

The shirasu light source 1 according to the present embodiment does not have to be specified in the form shown in FIGS. Form may be sufficient. Here, the aggregate of the LED light sources 5 is collectively referred to as a light source 14.
Furthermore, in the shirasu light source 1 according to the present embodiment, the case where the light source 14 is configured by the LED light source 5 is described as an example. However, as long as the wavelength and frequency as described below can be realized, A light source other than the LED light source 5, such as a halogen light, may be used.
Further, when the LED light source 5 is used in the light source 1 for catching shirasu according to the present embodiment, there is an advantage that the power consumption required for the light emission of the light source 14 can be reduced and the life of the light source 14 can be extended.
In addition, each LED light source 5 may be provided with a reflector so that the light for collecting shirasu radiated from the LED light source 5 can be efficiently emitted outside the light source 1 for catching shirasu. Alternatively, a reflective layer may be formed on the surface of the substrate 4 on the side where the LED light source 5 is provided.
In this case, since the light emitted from the LED light source 5 can be efficiently used for collecting fish, energy consumption at the time of collecting fish can be further saved.

Furthermore, in the light source 1 for shirasu fishing according to the present embodiment, the light emitted from the LED light source 5 (light for collecting shirasu) is blue to green having a maximum value in a wavelength region of 450 to 540 nm, and It is a flashing light whose frequency is set within a range of 10 to 50 Hz.
Thus, the shirasu collection light emitted from the light source 14 in the shirasu fishing light source 1 according to the present embodiment is set to blue to green having a maximum value in the wavelength region of 450 to 540 nm. The light can be highly sensitive to adult sardines (particularly anchovy). For this reason, Shirasu and its adult fish sardines can be collected near the light source 14 by emitting blue to green light having a maximum value in a wavelength region of 450 to 540 nm in water.
Moreover, as will be described later, it is possible to avoid the horse mackerel.

Further, in the shirasu light source 1 according to the present embodiment, the shirasu collection light emitted from the LED light source 5 is a blinking light whose frequency is set within a range of 10 to 50 Hz, so that the vicinity of the light source 14 The light source 14 can be repelled by adult sardine fish and fish other than the sardines (particularly horse mackerel).
As a result, shirasu can be gathered or moved mainly in the vicinity of the light source 14, and the light source 14 can be avoided in adult sardines and fish that are not intended.
As a result of diligent research, the inventors of the present invention have repelled sardines (particularly anchovy) in an undeveloped state of the eye, that is, at the stage of fry (shirasu), despite “flashing light”. They found that they gathered near the light source 14 without showing any action.
On the other hand, adult fish (mainly sardines, horse mackerel) with well-developed eye tissues find that when flashing light is emitted from the light source 14, they avoid the light source and do not come close to the light source. It was.
For this reason, in the shirasu light source 1 according to the present embodiment, blue to green having a maximum value in a wavelength region of 450 to 540 nm in which sardines (particularly anchovy) can be sensed in water, and a frequency of 10 to 50 Hz. By setting and blinking within the range, shirasu is closer to the light source 14, and adult sardines (especially anchovy) and undesired fish (mainly horse mackerel) are located further away from the light source 14. It can be collected or toured.
That is, according to the light source 1 for catching shirasu according to the present embodiment, it is possible to simultaneously exert a target fish collection or excursion effect and an undesired fish repellent effect using one light source. .

Here, with reference to FIG. 3, the shirasu fishing method according to the embodiment of the present invention will be described in detail.
FIG. 3 is a schematic diagram for explaining the shirasu fishing method according to the embodiment of the present invention. The same parts as those described in FIGS. 1 and 2 are denoted by the same reference numerals, and description of the configuration is omitted.
As shown in FIG. 3, the shirasu fishing method according to the present embodiment uses, for example, a shirasu fishing light source 1 (see FIGS. 1 and 2) connected to a power supply line 6 from a fishing boat 7 as a light source 14. As the light for collecting shirasu, it is emitted from blue to green having a maximum value in the wavelength region of 450 to 540 nm and its frequency is set in the range of 10 to 50 Hz. It is to do.
Then, if left in this state for a while, as shown in FIG. 3, the shirasu 8 (especially the anchovy fry) is in the vicinity of the light source 14 disposed in the water, and the sardines ( In particular, adult anchovy fish 10 and unintended fish 9 (mainly horse mackerel) gather or travel around.
Next, in the school of fish gathered around the light source 14, the ratio of the shirasu in the school of fish caught is greatly increased by scooping up the school of fish that is on the side of the light source 14 and has a larger proportion of fry than adult fish with the fishing net 13. Can do.

However, even if the above-described shirasu collecting light (flashing light) is emitted from the light source 14, the adult sardine fish may approach the vicinity of the light source 14. This may be due to an individual having low sensitivity to blue to green having a maximum value in the wavelength region of 450 to 540 nm, or an undeveloped adult fish with eye tissue.
Therefore, even if the shirasu light source 1 according to the present embodiment is used or the shirasu catching method according to the present embodiment, it is not possible to make all the fish schools to be caught only shirasu.
However, by using the shirasu light source 1 according to the present embodiment as described above, or according to the shirasu fishing method according to the present embodiment, while making the size of the landed shirasu more uniform, Contamination of adult sardines and unintended fish can be greatly reduced.
In this case, it is possible to drastically reduce the work of sorting the ground shirasu by size and removing the undesired fish from the shirasu obtained, so the freshness is high and the high-value-added size is high. Shirasu can be shipped easily. As a result, the profitability of the fishermen can be improved.

  Moreover, since the light for collecting shirasu emitted from the light source 14 (shirasu fishing light source 1) is blinking light, the power consumption can be reduced as compared with the case of using continuous light. For this reason, the expense at the time of performing shirasu fishing can be reduced. Therefore, the profitability of the fisherman can be further improved.

Further, in the present embodiment, anchovy larvae with a body length of up to 40 mm are used as the main catches, and larger ones are excluded by the sorting operation.
Here, the application target of the shirasu fishing light source 1 and the shirasu fishing method according to the present embodiment is an anchovy, but there is a possibility that the present invention can be applied to fish other than anchovy. Therefore, the application target of the shirasu light source 1 and the shirasu fishing method according to the present embodiment is not necessarily limited to anchovy.

Next, test results for supporting the effects and effects of the shirasu light source 1 and the shirasu fishing method according to the present embodiment will be described with reference to FIGS.
(1) About the wavelength region of light to which anchovy is sensitive The inventors of the present invention have measured the relative luminous sensitivity in order to clarify the wavelength region to which the anchovy that is the target of fishing is sensitive. In addition, specific luminous sensitivity (Luminosity function, or Photopic luminous efficiency function) expresses the intensity | strength in which an eye senses the brightness for each wavelength of light with a numerical value. In this test, adult anchovy fish were used.
FIG. 4 is a graph showing the measurement results of specific luminous sensitivity of anchovy. In addition, the vertical axis | shaft of the graph shown in FIG. 4 is specific luminous sensitivity V ((lambda)), and a horizontal axis is the wavelength (nm) of light.
As shown in FIG. 4, it became clear that the anchovy is highly sensitive to light having a peak in the wavelength region of 470 to 540 nm.

(2) About the wavelength of light and the fish collection effect The inventors of the present invention select red (peak wavelength: 635 nm), green (peak wavelength: 520 nm), and blue (peak wavelength: 470 nm) from the light source. We investigated the difference in fish collection effect between Japanese anchovy and horse mackerel when each of them was changed. All light used in this test was continuous light. In addition, adult anchovy and horse mackerel were used for this test.
FIG. 5A is a graph showing the distance from the anchovy and the horse mackerel light source when red light (peak wavelength: 635 nm) is emitted from the light source, and FIG. 5B is a graph showing green light (peak wavelength: 520 nm) from the light source. It is a graph which shows the distance from the light source of the anchovy and the horse mackerel at the time of emitting, and (c) is a graph which shows the distance from the light source of the anchovy and the horse mackerel when the blue light (peak wavelength: 470 nm) is emitted from the light source. . In addition, the test which shows a result in FIG. 5 was done in the water tank, and installed the light source in the water of the center of a 2 m radius water tank.
As shown in FIG. 5A, when red light (peak wavelength: 635 nm) was emitted from the light source, the anchovy did not respond and swam apart in the aquarium. As shown in FIG. 5B, when green light (peak wavelength: 520 nm) was emitted from the light source, both anchovy and horse mackerel traveled around the light source. However, anchovy tended to travel closer to the light source. Furthermore, as shown in FIG. 5 (c), when blue light (peak wavelength: 470 nm) was emitted from the light source, no measurement data was obtained because maji was avoided. On the other hand, anchovy collected fish near the light source.

FIG. 6A shows the distance from the anchovy light source when red light (peak wavelength: 635 nm), green light (peak wavelength: 520 nm), and blue light (peak wavelength: 470 nm) are emitted as continuous light from the light source. (B) shows a case where red light (peak wavelength: 635 nm), green light (peak wavelength: 520 nm), and blue light (peak wavelength: 470 nm) are emitted as continuous light from a light source. It is a graph which shows a time-dependent change of the swimming speed of anchovy. In addition, the test which shows a result in FIG. 6 was done in the water tank, and installed the light source in the water of the center of a 2 m radius water tank. In addition, adult anchovy fish were used in this test.
As shown in FIGS. 6 (a) and 6 (b), when green light (peak wavelength: 520 nm) and blue light (peak wavelength: 470 nm) are emitted as continuous light from the light source, the fish collection effect continues to be exhibited. It was done. In this case, the anchovy collected or traveled in the range of 0.5 to 1.5 m from the light source. On the other hand, when red light (peak wavelength: 635 nm) was emitted from the light source as continuous light, the anchovy fish collection effect was not exhibited.
Therefore, it was confirmed that at least blue to green light (470 to 520 nm) has an anchovy fish collection effect.

(3) About behavior when flashing light having different frequencies is emitted from the light source The inventors of the present invention investigated the behavior of anchovy when the frequency of light emitted from the light source is different.
FIG. 7A is a graph showing the change over time of the distance from the light source of anchovy when green light (peak wavelength: 520 nm) is irradiated from the light source at different frequencies, and FIG. It is a graph which shows a time-dependent change of the swimming speed of the anchovy when it irradiates by changing a frequency (wavelength: 520nm). In addition, the test which shows a result in FIG. 7 was done in the water tank, and installed the light source in the water of the center of a 2 m radius water tank. For the test, adult anchovy fish were used.
As shown in FIG. 7A, when the frequency of green light (peak wavelength: 520 nm) emitted from the light source is set to 100 Hz, 20 Hz, 10 Hz, and 0.5 Hz, the frequencies are 100 Hz, 20 Hz, and 10 Hz. At times, anchovy tended to gather. On the other hand, when the frequency was set to 0.5 Hz, the anchovy did not gather.
Moreover, as shown in FIG.7 (b), when the frequency of the green light (peak wavelength: 520 nm) emitted from a light source is lower than 10 Hz, the tendency for the swimming speed of anchovy increased was recognized.
Therefore, even when the light emitted from the light source is blinking light (however, the frequency is 10 Hz or more), it is considered that the anchovy fish collection effect is exhibited.

(4) Effect of blinking light on horse mackerel and anchovy The inventors of the present invention investigated the effect of blinking light on horse mackerel and anchovy.
More specifically, white light (blue light: 470 nm, yellow light: 570 nm) obtained by mixing blue-green light (peak wavelength: 500 nm) and blue light and yellow light in the water in the center of a cylindrical water tank having a radius of 2 m. ) Radiating light source, swimming the horse mackerel and anchovy singly separately, lighting the continuous light from 0 to 30 minutes, and then changing the frequency to 1.3 Hz, 10 Hz, and 55 Hz from 30 minutes to 50 minutes, respectively. The set flashing light (intermittent light) was irradiated, and the light response behavior of the horse mackerel and the anchovy was observed.
Fig. 8 (a) shows a blue-green light (peak wavelength: 500 nm) and white light (blue light: 470 nm, yellow light: 570 nm) mixed with blue light and yellow light for 30 minutes in a state where the horse mackerel is swimming. It is a graph which shows the distance from the light source of the horse mackerel at each time when the blinking light (intermittent light) which set the frequency as 1.3 Hz, 10 Hz, and 55 Hz, respectively, was irradiated for 20 minutes after irradiation. In (b), blue-green light (peak wavelength: 500 nm) and white light mixed with blue light and yellow light (blue light: 470 nm, yellow light: 570 nm) were continuously irradiated for 30 minutes while swimming an anchovy. Then, it is a graph which shows the distance from the light source of the anchovy at each time when the blinking light (intermittent light) which set frequency as 1.3 Hz, 10 Hz, and 55 Hz, respectively, is irradiated for 20 minutes.
As shown in FIG. 8A, in the case of a horse mackerel, in the case of blinking light (intermittent light) of 1.3 Hz, the distance from the light source is about 130 cm immediately after switching, and the width of 25-75% is about 70 cm. Spread. On the other hand, in the case of 10 Hz, the distance was about 160 cm immediately after switching, and the width of 25-75% became as narrow as about 20 cm. On the other hand, in the case of 55 Hz, there was almost no change in the light-sensitive behavior even after switching. From the above, it is considered that repelling behavior did not occur for blinking light (intermittent light) 55 Hz. On the other hand, at 1.3 Hz and 10 Hz, it is thought that they showed repelling behavior because they were away from the light source, but compared with 1.3 Hz, the whole school of fish started to swim near the wall more smoothly at 10 Hz. It is thought that the repellent effect was strong.
As shown in FIG. 8B, in the case of anchovy, in the case of 1.3 Hz, the swimming speed immediately after that is slowed down to 5/8 of the previous value, and it is assumed that the state was alert. The distance from the light source was almost the same as that immediately before switching, and it was swimming at almost the same position until the end of the intermittent light. On the other hand, at 10 Hz and 55 Hz, there was almost no change in the median values of the swimming speed and the distance from the light source immediately after switching. It was observed that the distance from the light source approached as time passed.
The data analysis was performed by using image analysis software and measuring the positions from the light sources of five individuals, the horse mackerel and the anchovy, every second.

  As described above, the present invention is a shirasu catch that can efficiently catch shirasu, which is a juvenile, in a uniform size and with less contamination of fish that are not subject to catch, while saving power consumption at that time. It is a method and a light source for shirasu fishing used therefor, and can be used in fields related to research, development and protection of fisheries and marine resources.

  DESCRIPTION OF SYMBOLS 1 ... Light source for Shirasu fishing 2 ... Main part 3 ... Casing 4 ... Board | substrate 5 ... LED light source 6 ... Power supply line 7 ... Fishing boat 8 ... Shirasu (sardine fry) 9 ... Horse mackerel 10 ... Anchovy (adult sardine) 11 ... Control unit 12 ... Power supply 13 ... Fishing net 14 ... Light source

Claims (5)

  A shirasu catching method characterized by emitting blue to green shirasu collection light having a maximum value in a wavelength region of 450 to 540 nm in water while blinking at a frequency of 10 to 50 Hz.   2. The fish school that is collected near the light source that emits the light for collecting shirasu or that travels around the light source and catches the fish school that is on the light source side and has a larger proportion of fry than adult fish. Shirasu fishing method.   The shirasu fishing method according to claim 1, wherein the shirasu that is a target of fishing is an anchovy fry. An LED light source that emits shirasu collection light in water, and a control unit that can control at least the frequency of the shirasu collection light emitted from the LED light source;
The light source for collecting shirasu, characterized in that the light for collecting shirasu is blue to green having a maximum value in a wavelength region of 450 to 540 nm and blinks at a frequency of 10 to 50 Hz.   5. The light source for catching shirasu according to claim 4, wherein the shirasu that is a target of fishing is an anchovy fry.