JP3749859B2 - White eel fishway system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a glass eel fishway system provided in an estuary weir or the like for the purpose of moving up a glass eel, that is, a fry of a salmon.
[0002]
[Prior art]
As is well-known, juvenile sea breams come to various rivers on the ocean from warm waters as wrinkled white eels with a length of around 10 cm. In Japan, visitors generally travel from November to April, but glass eels that have arrived at the river mouth will run up to the river when conditions suitable for running up, such as river water temperature, high tide time, sunset time, and tide height, are ripe. It seems to start. The run-up of the glass eel takes place almost at night. In other words, the glass eel starts to move with sunset, climbs the river on high tide, and has the habit of resting by hiding in a fish reef and the like near dawn. In this way, the glass eel grows while going up the river etc. by repeating such a run-up, and further goes up to the final purpose such as a small ditch, a lake, a swamp, a lagoon, etc., and becomes an adult fish (carp). The moths grown there for a period of time in the upstream have the habit of returning to the warm sea down the river and laying eggs when the water temperature begins to fall in the fall. The camellia that grew up from the glass eel in the river and the like is not only as a natural moth but also as a mother of the glass eel.
[0003]
On the other hand, most rivers are provided with river mouth weirs or sluices for various purposes in the downstream. These estuary weirs or sluices block the river flow in the transverse direction and prevent the fish and fish that live there from moving in the upstream direction. (Fish artificial waterway) is provided.
[0004]
[Problems to be solved by the invention]
However, the existing fishway is designed for fish with a comparatively swimming ability, such as carp and carp that are considered to be useful in the fishery economy. The flow of the fishway is relatively fast. However, it is almost impossible for a glass eel with the habit of going up along a gentle flow or where there is a little moisture or a small flow to go up through the fast-flowing fishway as described above. . It has long been said that the number of natural spiders has been drastically reduced, but this is also due to the fact that glass eels are caught for aquaculture near the estuary, but the glass eels are blocked by estuary weirs and so on and so on. It can be said that it is the biggest cause. In particular, the fact that there is no white eel fishway at the estuary weir or sluice is the cause of the absence of smallpox upstream.
[0005]
Accordingly, an object of the present invention is to provide a glass eel fishway system that enables glass eels that reach river mouth weirs and sluices to easily run up and increase the presence of corals on the upstream side.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the present invention adopts the following means to exhibit the following effects.
[0007]
(Characteristics of the invention described in claim 1)
The glass eel fishway system according to the present invention is composed of four elements, that is, a guide water supply unit, a water channel unit, a fish collection unit, and a guide unit. It is made to be able to go up. The induction water supply unit is an apparatus for supplying water for the run-up of glass eel to the system. This unit includes a guide water supply means such as a pump and a guide water tank for storing the pumped-up guide water. The guide water tank can supply guide water to the water channel unit and the guide unit. Further, the above-mentioned water channel unit is a unit including a water channel pipe provided in an inclined shape on the downstream side of the dam, and the guide water supplied from the above-mentioned guide water supply unit is provided to be able to flow down from the dam to the downstream side. It is. The guide water is allowed to run up the glass eel by flowing down from the fish collection unit to the downstream side of the dam through the water pipe.
[0008]
The fish collection unit is a unit installed on the water surface on the downstream side of the estuary weir in order to collect many glass eels and guide them from the riser to the channel unit. The structure of the fish collection unit consists of an inlet pipe connected to the above-mentioned water pipe, a floating body that partially lifts the riser that is also the entrance of this inlet pipe, and a fish collection that collects glass eel around the riser It is characterized in that it is provided with means. This is because glass eels have the habit of swimming at the water's edge, so that an ascending port is provided at the water's edge to facilitate guidance into the entrance pipe. Along with this, glass eels, like other fishes, have the habit of reacting to light and falling sounds of water, and it is easy to guide to the entrance pipe by providing fish collection means.
[0009]
The guidance unit is a device for guiding the glass eel that has run up the waterway unit so as to move from the upstream end to the upstream side of the dam. Since glass eels have the habit of moving upstream, after reaching the dam, it is not preferable to jump off the water surface on the upstream side. It is for guiding to jump over the end.
[0010]
Through the installation of the system according to the present invention, the glass eel collected around the fish collection unit enters the entrance pipe from the riser, and ascends the waterway unit through which the guide water supplied from the guide water supply unit flows up to the guide unit. To do. Further, it jumps over the upstream end of this guidance unit and can move to the upstream side of the estuary weir. Thus, by allowing the glass eel to climb over the estuary weir, it is possible to inhabit natural moths in upstream rivers and lakes, and to build a foundation that enables the reproduction of glass eels.
[0011]
(Characteristics of the invention described in claim 2)
In the induction unit according to the second aspect of the invention, a part of the amount of the induced water supplied from the first water injection pipe connected to the induction water supply unit is transferred from the upstream end of the induction unit to the upstream side of the dam. The remaining amount is provided to be able to flow downstream from the dam, and the induced water supplied from the second water injection pipe connected to the induced water supply unit can be allowed to flow outside the upstream end. There are some features. The induced water supplied from the first water pipe is poured so that a part of the amount of water flows down from the upstream end of the induction unit to the upstream and downstream sides of the dam at the same time. Performs the action of inducing to go over the upstream end in order to continue going up further. The glass eel that has overcome the upstream end in this way jumps out to the upstream side of the dam, but in response to this, the induced water supplied from the second water injection pipe is allowed to flow outside the upstream side end, thereby causing the upstream side of the dam to flow upstream. Easy to navigate to.
[0012]
(Characteristics of the invention described in claim 3)
In the glass eel fishway system according to the present invention, the water channel unit is composed of a fixed water channel tube fixed to the dam and a movable water channel tube provided so as to swing in response to the raising and lowering of the fish collecting unit. There is a feature. Since the fish collection unit is installed on the downstream side of the estuary weir, etc., it moves up and down in response to changes in the tide level. It is necessary to keep the unit at the shore and keep it level. As a means to achieve this, it is composed of a fixed channel pipe that is a part where the channel unit is fixed to the dam, and a movable channel pipe that connects the fixed channel pipe and the fish collection unit. It is designed to maintain a state where fish can be collected at all times.
[0013]
(Feature of the invention described in claim 4)
The white eel fishway system according to the present invention is characterized in that the water channel pipe of the water channel unit is provided so as to be held by a support member fixed to the dam. Here, the support member refers to a member provided to support the water channel pipe and the fish collection unit so as to hold a predetermined position with respect to the dam. The fish collection unit is provided on the downstream side of the estuary weir and is placed in an environment where it is tampered with by tidal currents and winds, so it is often difficult to tether it to the original installation position. Therefore, by supporting these with a support member, it is possible to guide the run-up of the glass eel by the fish collection unit.
[0014]
(Feature of the invention described in claim 5)
The invention described in claim 5 is characterized in that any of the water pipes in the invention described in claims 1 to 4 is provided with a baffle that facilitates the run-up of the glass eel. Here, the baffle means a simulated seaweed or the like provided at the bottom of the water channel pipe in order to weaken the flow in the water pipe and facilitate the upward movement of the glass eel. Since glass eels do not have the ability to run up a steep slope against a rapid stream, these water pipes are provided with a baffle to weaken the water flow and cause the glass eel to wind between the baffles. While helping to climb the inclined surface.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
As shown in FIG. 1, this embodiment forms the basic configuration of a glass eel fishway system, and is mainly considered to be installed in an estuary weir provided in a estuary where the tide is not large. It is a configuration. In this system, a water supply unit 3 is provided on the dam 1 of the estuary weir, and a fish collection unit 5 is provided at the waterside downstream of the dam (right side in FIG. 1). Further, between the water supply unit 3 and the fish collection unit 5, there is a water channel unit 7 that connects both of them, and the guide water discharged from the water supply unit passes through the water channel pipe 8 of this water channel unit. It has come to flow to. The upstream end of the water channel unit 7 is connected to the guidance unit 9. As a result, the glass eel that has run up through the water pipe 8 is guided from the guiding unit 9 to the upstream side of the dam 1. Thus, the glass eel that has reached the downstream side of the dam 1 of the estuary weir from the ocean enters the guiding unit 9 from the fish collection unit 5 through the water channel unit 7, and is guided upstream from here to the upstream side of the dam. ing.
[0016]
The water supply unit 3 includes a guide water tank 3a installed on the dam 1 and water supply means 4 for supplying guide water to the tank. The water supply means 4 includes a submersible pump 4a and a water supply pipe 4b that connects the submersible pump 4a and the induction water tank 3a. The installation location of the submersible pump 4a is not particularly limited, but it is desirable that the guide water is the same water as the water to which the glass eel heads, and that the water source is easily obtained. The left side of FIG. 1 is desirable. Two water injection pipes for injecting the induction water to the induction unit 9 are provided on one side of the induction water tank 3a. The first water injection pipe 12 a located on the inner side can mainly be injected into the water channel unit 7, and the second water injection pipe 12 b located on the outer side can be injected onto the inclined surface of the dam 1. The water injection amount of each water injection pipe can be adjusted by the adjustment valve 12c.
[0017]
The fish collection unit 5 is a device for collecting and guiding the glass eels that have reached the estuary weir and sending them to the water channel unit 7. The fish collecting unit 5 includes an inlet pipe 5a, a floating body 5b, a light 6a and a shower 6b constituting the fish collecting means 6 as main components. As the inlet pipe 5a, a plastic pipe such as vinyl chloride (PVC) having a diameter of 300 to 400 mm cut into a length of about 1 m is employed. As shown in FIG. 2, the upstream end of the inlet pipe 5a is connected to the flexible pipe 5d, which can cope with changes in the tide level. The floating body 5b employs a floating body such as a polystyrene foam fixed to both sides of the inlet pipe 5a. In addition, the inlet pipe 5a is arranged via the floating body 5b so that the longitudinal direction is horizontal on the water surface, but as shown in FIG. 3, about one third from the upper part of the cross section of the rising port 5c. It is desirable to be on the surface of the water. This corresponds to the behavior of glass eels swimming at the water's edge and facilitates the induction of glass eels into the fishway system. The light 6a that constitutes the fish collecting means 6 shown in FIG. 1 acts to call around the rising mouth 5c by using the habit of gathering glass eels in a bright place or the habit of gathering in places where water noise is generated. As the light, it is desirable to use an incandescent lamp of about 100 W so as to illuminate the periphery of the riser 5c. Also, the shower 6b may be sprayed with water overlapping the lighting range.
[0018]
As described above, the water channel unit 7 is a fishway water channel interposed between the water supply unit 3 and the fish collection unit 5. As the water pipe 8, it is desirable to adopt a circular pipe made of PVC and having a diameter of about 300 to 400 mm. In addition, since a cast iron pipe and a steel pipe generate | occur | produce rust, it is not preferable as a water pipe of this system. As shown in FIGS. 4 and 5, the water channel pipe 8 is formed into a tubular shape by combining the pipe portion 8 a and the upper lid portion 8 b, and internal maintenance is facilitated by attaching and detaching the upper lid portion. In addition, lighting and air supply can be performed by providing a window portion 8c at an important point of the upper lid portion 8b. Although the water channel pipe 8 is installed via the anchor member 8d along the downstream inclined surface of the dam 1, it is necessary that the vertical installation angle be within 60 ° so that the glass eel can be run up. The water pipe 8 is connected to the flexible pipe 5d and the subsequent inlet pipe 5a through a pipe joint 8e. Further, at the bottom of the water channel pipe 8, rocks are arranged as a baffle for facilitating the upward movement of the glass eel, and pseudo seaweed and the like are further planted.
[0019]
In FIG. 1, the guidance unit 9 is fixedly installed on the dam 1, and the configuration thereof includes a storage water tank 10 connected to the upper end portion of the water channel pipe 8, and the two water injection pipes 12 a and 12 b described above. Consists of. This storage water tank 10 is a water tank having a width of about 400 mm and a length of about 2 m with a gradient of about 1/10 placed on the dam 1, and the downstream end of the water pipe 8 Connected to the upper end. The upstream end of the storage water tank 10 is a guiding part 10a described later. Further, since the storage water tank 10 is a facility for resting the glass eel that has run up the steep water channel pipe 8, it is preferable to scatter pebbles or plant a pseudo-aquatic plant. Moreover, it is also possible to observe the state of the glass eel that has been run up by configuring the lid of the culture water tank 10 with a transparent plate, or to provide a fish shadow detection sensor in the water tank so that the amount of run up of the glass eel can be measured. . Furthermore, a bypass can be provided as an accessory facility, and glass eels can be supplemented and supplied to other sericulture farms.
[0020]
The guide part 10a is a part without a lid provided in the upstream part of the storage water tank 10, and it is possible to supply the guide water from the first water injection pipe 12a, and a glass eel escapes over the edge of the upper end part. It is possible. Thus, of the two water injection pipes 12a and 12b, the inner water injection pipe 12a is poured onto the edge plate of the guiding portion 10a, and about half of the amount of water injection is provided to flow out of the tank. Then, the remaining water injection amount is poured into the guiding portion 10 a and flows from here into the water pipe 8 through the storage water tank 10. In this way, a part of the water injection amount falls outside the tank because the glass eel makes an illusion that the upstream path continues outside the upstream end of the guiding portion 10a and jumps over the edge plate. Thus, it is expected to induce the action. On the other hand, when the other irrigation pipe 12b heads up upstream and jumps out of the tank over the upper edge of the tank at the part where the white eel that is going up from the inner water injection pipe 12b is injected, It functions to be washed away and dropped to the upstream side of the dam 1. It is preferable to provide an inclined surface 1a on the dam 1 below the guiding portion 10a so that the glass eel that has passed over the guiding portion slides down along this gradient and then drops onto the water surface with a small impact. Furthermore, it is preferable to provide a reverse run-up prevention unit 1b composed of a vertical wall for preventing reverse run-up between the water surface and the inclined surface 1a.
[0021]
The glass eel has the habit of starting to move as it darkens in the evening, brightens at dawn, and stops its activity. Therefore, the system should be operated only during this time. Further, as described above, the period of rising glass eels is also limited to November to April in Japan, so the establishment of this system may be limited to this period. Therefore, it is possible to disassemble the complete system and store it in a warehouse or the like during periods other than this period, and reconstruct it in accordance with the run-up period in November.
[0022]
In operation of this system, the submersible pump 4a is started, the guide water is stored in the guide water tank 3a, and the control valve 12c of the water injection pipe 12a is adjusted to supply the guide water to the guide unit 9. At the same time, the light 6a of the fish collection unit 5 is turned on, water is sprayed in the shower 6b, and glass eels are called up around the ascending mouth 5c. The glass eels gathered here sense the water flow discharged from the ascending port 5 c and start going up from here toward the water channel unit 7. Since glass eels have the habit of moving in the direction if there is only a small amount of water, in other words, if there is moisture, the amount of induced water may be small. In the aqueduct 8, a disturbing substance such as a simulated aquatic plant is provided, so that the glass eel travels along these obstacles and eventually reaches the storage tank 10. The glass eel that has reached the livestock aquarium 10 is rested here, and then continues to run up to the guiding part 10a, where it rides on the water injection from the first water injection pipe 12a, gets over the upper edge of the tank and goes outside the tank. Jump out to. As described above, the glass eel that has jumped out of the tank is swept away by water injection from the second water injection pipe 12b, slides down the inclined surface 1a of the dam, and falls onto the upstream water surface. The glass eel that has reached the upstream side over the dam 1 has grown further and continues to grow.
[0023]
(Second embodiment)
As shown in FIG. 6, the basic configuration and operation of this embodiment are the same as those of the first embodiment. However, in this embodiment, the first configuration is simplified in the configuration and construction method of equipment. There are features. In other words, each unit is easy to disassemble and assemble, and this system can be constructed or removed at low cost so that it can be installed only during the run-up period of glass eels. This is intended to prevent damage in the event of a typhoon. The second feature is that the water channel pipe 28 constituting the water channel unit 27 is composed of a fixed water channel pipe 28a and a movable water channel pipe 28b, so that the horizontal state of the inlet pipe 25a is maintained even when the raising and lowering movement of the fish collection unit 25 is increased. It is possible to respond while maintaining it.
[0024]
Since the configuration of this embodiment is based on the first embodiment, as shown in FIG. 6, the reference numerals of the units having the same names are the same as those used in the first embodiment. 20 is added. In addition, numerical values of 20 or more and less than 40 are adopted for components other than each unit. The configuration of each unit is also different from that of the first embodiment in the drawing, but these differences are within the scope of changes made in response to various conditions.
[0025]
The outline of the configuration of this embodiment is that a water supply unit 23 is provided on the dam 21 of the estuary weir, and a fish collection unit 25 is provided on the water surface downstream of the dam. The water channel unit 27 that connects the water supply unit 23 and the fish collection unit 25 includes a fixed water channel tube 28 a that is provided horizontally on the dam 21 and a movable water channel tube 28 b that connects the fixed water channel tube and the fish collection unit 25. is there. In the fish collection unit 25, the entrance pipe 25a connected to the tip of the movable water pipe 28b is configured to maintain a posture in which the ascending opening 25c can be easily collected by floating bodies 25b and 25b provided on both sides. On the floating body 25b, a ridge 25f is built, and a light 26a and a shower 26b constituting the fish collecting means 26 are provided on this.
[0026]
The fixed water pipe 28a and the movable water pipe 28b and the movable water pipe and the fish collection unit 25 are connected via a flexible pipe. For this reason, the fish collection unit 25 can always be held horizontally on the water surface even when the water level changes greatly due to tidal flow or the like on the downstream side. This movable water channel pipe 28b is suspended by ropes 27c,... On an inspection corridor 22 provided so as to project from the dam 21 to the downstream side. This is adopted to prevent the fish collection unit 25 from drifting by waves and winds, but it also realizes cost reduction of equipment by adopting a simple configuration.
[0027]
In addition, in this embodiment, the livestock water tank 30 provided in the guidance unit 29 is provided horizontally on the dam 21, and the upstream end projects from the upper part of the dam to the upstream side, and the fixed water pipe 28 a The connecting portion 30b is stepped. And the 1st water injection pipe 32a which supplies the induced water supplied from the fish collection unit 25 to the fixed water channel pipe 28a and the 2nd water injection pipe 32b which supplies water to the animal water tank 30 are provided separately. First, the guide water supplied from the first water injection pipe 32a is injected into the middle of the fixed water pipe 28a, and then flows into the movable water pipe 28b disposed obliquely. The guide water supplied from the first water injection pipe 32a also flows slightly upstream of the water injection position, but it is desirable that this amount be sufficient to help the glass eel run up. In addition, if the glass eel that has passed through the connecting portion 30b has a structure in which it cannot be returned, all the glass eels can move into the animal water tank 30. The feed water tank 30 is filled with guide water from the second water injection pipe 32b, and is provided with a low weir at its extreme end, and its leading end is used as a guide part 30a. It is supposed to be out.
[0028]
The movable water channel pipe 28b in this embodiment is provided so as to protrude in a direction perpendicular to the downstream side from the dam 21, but it may be provided so as to be parallel to the dam as shown in FIG. Good. This is advantageous in that maintenance is facilitated because both the movable water pipe 28b and the fish collection unit 25 are located near the dam 1.
[0029]
(Third embodiment)
This embodiment focuses on the fact that the above-described second embodiment makes it easy to install and remove the system, while the basic configuration is almost the same, but the equipment should be made permanent. The main focus is on. Therefore, the reference numerals used in the description of the drawings are the same as those in the second embodiment, but a numerical value obtained by adding 20 to the reference numerals is used. As shown in FIGS. 8 and 9, the water channel unit 47 is held by support members 47a and 47b. That is, the fixed channel pipe 48a is supported by a fixed support member 47a fixed to the dam 41, and the movable channel pipe 48b is a movable unit that is attached to the fixed support member so as to be swingable in the vertical direction via a support shaft 47c. It is held by the support member 47b. For this reason, the fish collection unit 45 can be sufficiently moved even if it moves up and down due to a change in the tide level, and it can be kept at the original installation position even if it is pushed away by wind.
[0030]
The fish collecting unit 45 includes an inlet tube 45a, a floating body 45b, and a fish collecting means 46. The fish collecting means is installed on a rod 47d that is floated on the surface of the water by the floating body. At the same time, the inlet pipe 45a is attached to the flange 47d, and the ascending opening 45c is provided so that about one third of the rising pipe 45a always comes out on the water surface. The fish collection means 46 installed on the rod 47d is provided with a light 46a and a shower 46b as in the first and second embodiments. The flange 47d is swingably supported by the movable support member 47b via the support shaft 45e at the tip of the movable support member 47b. Therefore, even if the eaves 47d move up and down due to a change in the tide level, the eaves 47d can float while maintaining the horizontal state via the movable support member 47b. The fixed conduit pipe 48a employs a normal PVC pipe, but the movable conduit pipe 48b employs a flexible tube so that the horizontal state can be maintained when the inlet tube 45a moves up and down due to fluctuations in the tide level. . The movable water channel pipe 48b may be swingable at both ends via a flexible pipe. Other configurations are the same as those of the second embodiment.
[0031]
In addition, the shape and arrangement of each component in the above three embodiments are described as examples only, and it is actually desirable to change them according to the installation state of the estuary weir and the structure of the dam. In addition, it is desirable to deal with the dimensions of risers and water pipes and obstructions according to the actual situation.
[0032]
【The invention's effect】
According to the present invention, it is possible to easily provide a glass eel run-up fishway consisting of simple equipment in an existing estuary weir, etc., so that a glass eel can be run upstream from the downstream side of the estuary weir. it can. Therefore, it has been impossible to run up glass eels because only fishways such as corals and corals have been established so far, but this fishway system has been installed to get over the estuary weir and go further upstream from the upstream. Because it can live upstream, it contributes to the protection of valuable smallpox. In addition, if a smallpox returns to the sea down the river and lays eggs, it contributes to the reproduction of the glass eel, which contributes to the reup of the glass eel and the reproduction of the cocoon.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a configuration of a first embodiment.
FIG. 2 is an explanatory view showing an installation state of an inlet pipe.
3 is a cross-sectional view taken along line BB in FIG.
FIG. 4 is a plan view showing a configuration of a water pipe.
5 is a cross-sectional view taken along line DD of FIG.
FIG. 6 is an explanatory diagram showing a configuration of a second exemplary embodiment.
FIG. 7 is an explanatory diagram showing another configuration of the second embodiment.
FIG. 8 is an explanatory diagram showing a configuration of a third exemplary embodiment.
FIG. 9 is a plan view showing a configuration of a third exemplary embodiment.
[Explanation of symbols]
1,21,41 Estuary dam (dam)
3, 23, 43 Water supply unit
4, 24, 44 Guide water supply means (water supply means)
5, 25, 45 Fish collection unit
5a, 25a, 45a Entrance pipe
5b, 25b, 45b Floating body
5c, 25c, 45c
6, 26, 46 Fish collection means
7, 27, 47 Waterway unit
8, 28, 48 water pipe
9, 29, 49 Guidance unit
12a, 32a, 52a 1st water pipe
12b, 32b, 52b Second water pipe
28a, 48a fixed channel pipe
28b, 48b Movable water pipe
47a, 47b Support member

Claims (5)

A guidance water supply unit, a water channel unit, a fish collection unit, and a guidance unit;
The guide water supply unit includes a guide water tank provided on a dam such as an estuary weir, and guide water supply means for supplying guide water to the guide water tank.
The water channel unit includes a water channel pipe capable of flowing the guide water supplied from the guide water supply unit to the downstream side of the dam,
The fish collecting unit includes an inlet pipe connected to the downstream end of the water pipe, a floating body that partially lifts the rising port that is an opening of the inlet pipe, and a periphery of the rising port. Fish collection means for collecting the above glass eels,
The guidance unit is provided so that the glass eel that has run up the waterway unit can be guided from the upstream end to the upstream side of the dam,
The white eel collected around the fish collection unit enters the entrance pipe from the riser, goes up to the guidance unit through the water channel pipe, climbs over the upstream end of the guidance unit, and enters the estuary weir. A fishway system for white eels, which is movable upstream. 2. The guide unit according to claim 1, wherein a part of the amount of the guide water supplied from the first water pipe connected to the guide water supply unit is upstream of the dam from the upstream end of the guide unit. The remaining amount is provided downstream of the dam so that the remaining amount can flow down, and the induced water supplied from the second water injection pipe connected to the induced water supply unit is supplied to the upstream end portion. A glass eel fishway system characterized by being able to flow outward. 3. The water channel pipe according to claim 1, wherein the water channel pipe is fixed to the dam, is connected to the fixed water channel pipe, and swings in response to the raising and lowering of the fish collecting unit. A fishway system for white eel characterized by comprising a movable water channel pipe provided as described above. 4. The white eel fishway system according to claim 3, wherein the water channel pipe is provided so as to be held by a support member fixed on the dam. 5. A glass eel fishway system according to any one of claims 1 to 4, wherein the water channel pipe is provided with a baffle for facilitating ascending the glass eel.

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