JP4703177B2 - Bird protection equipment in the fishway - Google Patents

Description

  The present invention relates to a bird protection device in a fishway that allows a fish to pass through a fishway installed in a dam or a weir, etc., by preventing the fish passing through the fishway from being caught by birds.

Structures such as dams or weirs that are installed across rivers to form inundation ponds disrupt or obstruct the natural flow of river water, making it difficult for fish living in rivers to move or It becomes an obstacle to make impossible. Therefore, these structures are provided with a fishway made of U-shaped grooves that allow fish to pass through. As a general fishway installed in a dam or a weir, there is a fishway with a stepped waterway.
However, when such a fishway passes through a narrow channel for fish mainly going up, it is a good feeding ground for birds, and fish are often preyed on.
Therefore, Japanese Patent Application Laid-Open No. 2004-68571 “Fish upstream structure and waterway member used therefor” has proposed a technology in which a prevention net is provided to cover the upper side of the fishway in order to protect the fish from bird predation. .
This Patent Document 1 discloses a structure in which a support frame is attached to a waterway member constituting a fishway, and a prevention net is attached so as to cover the upper side of the fishway through the support frame. Thereby, the predation by the birds of the fish going up the fishway is prevented, and the safety of the fish going up is ensured.
JP 2004-68571 A

  However, the invention described in Patent Document 1 is to attach a plurality of inverted U-shaped support frames to the upper edge of the waterway member constituting the fishway, and to cover these support frames with a prevention net, There was a problem that a lot of labor and cost were required for the construction.

  The present invention has been made to solve the above-mentioned problems, and its purpose is to easily attach to an existing fishway with a simple structure and to effectively protect fish from bird predation. An object of the present invention is to provide a birdproof device for a fishway.

The present invention was created by paying attention to the property of hating wings and body touching something when birds try to land or flap.
In order to solve the above-mentioned problem, the bird protection device in the fishway according to claim 1 is a bird protection device in the fishway (1) installed to allow the fish (F) to pass through, and flies for predation. An upstream side support member (10, provided on the upstream side of the fishway (1) so that the wings or body of the birds (B) come into contact when the birds (B) land in or near the fishway (1) 20, 50) and a downstream support member (11, 21, 51) provided on the downstream side, a plurality of flexible string bodies (3) are stretched above the fishway (1), It is characterized by that.

Botori device in fishway (1) according to claim 2, Ru raises and lowers the river the downstream support member provided above the outlet to be connected to (R) (1out) (21) of the fishway (1) The elevating means (22) is provided at the outlet (1out) .

The Botori device in fishway (1) according to claim 3, at least one of the fishway plurality alongside stretched by flexible cords in the width direction of the (1) (3), the fish pass (1 ) Is disposed above the side wall (2) constituting the structure.

The bird protection device for the fishway (1) according to claim 4 , wherein the bird (B) is stretched over and above the upper surface of the side wall (2) constituting the fishway (1) so that the bird (B) does not stop on the side wall (2). setting the flexible cords interval and (3), the overall height than the narrow Kushida fish (F) subject avian among birds prey on (B) (B), characterized in that.

6. The bird protection device in the fishway (1) according to claim 5 , wherein the birds (B) that prey on the fish (F) have a plurality of flexible cords so that the interval is approximately half the length of the wings. The body (3) is stretched.

7. The bird protection apparatus for a fishway (1) according to claim 6 , wherein the downstream support member (11) or the upstream support member (20) is a hook for hooking a stretched flexible string (3). a member (12), the flexible cords (3) and a weight for the rod member (13) for adding tension, weight for rod member the ends of the flexible cords (3) ( 13), and the weight bar member (13) is suspended by hanging the position of the flexible string (3) in the vicinity of the weight bar member (13) on the hooking bar member (12). It is provided in a lowered shape.

The Botori device in fishway (1) according to claim 7, the weight for the rod member (13), suspended via a resilient member (14) to said hook for rod member (12), that Features.

The bird protection device for the fishway (1) according to claim 8 , wherein the hooking rod member (12) is provided with a slip prevention means (15) for preventing the flexible string (3) from shifting in the parallel direction. It is provided.

The birdproof device in the fishway (1) according to claim 9 , wherein the slip prevention means (15) is a structure in which the flexible string (3) is wound around the hooking rod member (12) by one or more rounds. It is characterized by being.

The bird protection device for the fishway (1) according to claim 10, wherein the slip prevention means (15) is a slip prevention member (40) rotatably supported by a hooking rod member (12). The prevention member (40) has a structure in which a V-groove (41) into which the flexible cord (3) is fitted is formed on the outer peripheral surface.

According to the birdproof device in the fishway (1) according to claim 1, since a plurality of flexible string bodies (3) are stretched above the fishway (1), the birds (B ) Will not be able to land on the fishway (1) or in the vicinity of the fishway (1) because it will come into contact with these flexible cords (3), so it will mainly run up the fishway (1). It is possible to protect the fish (F) passing at the time of predation of birds (B).
In addition, since the plurality of flexible cords (3) are stretched between the upstream support member (10, 20, 50) and the downstream support member (11, 21, 51) provided on the downstream side. , Ru can be easily stretched flexible cord body (3) in the longitudinal direction of the fish pass (1). Thus, it is possible to reduce the number of flexible cords (3), requires less place to Tsunagiyui its ends, the workability can Rukoto improve maintainability.

According to the bird protection device in the fishway (1) according to claim 2 , since the elevating means (22) that allows the downstream support member (21) to be raised and lowered is provided, the river (R) when the dam (D) is discharged ), The downstream support member (21) and the flexible string (3) are prevented from being flooded, and they are prevented from being washed away by the flow of the river (R). Can be prevented from adhering.

According to the anti-bird device in the fishway (1) according to claim 3 , the flexible string (3) is arranged above the side wall (2) such as a U-shaped groove constituting the fishway (1). Therefore, landing on the upper surface of the side wall (2) of the flying bird (B) can be effectively prevented.

According to the bird-proofing device in the fishway (1) according to claim 4 , the distance between the upper surface of the side wall (2) and the flexible string (3) is the same as that of the bird (B) that prey on the fish (F). among since the smallest ones were narrower comb than the total height, flying to have birds (B) can be reliably prevented from stopping on the upper surface of the side wall (2).

According to the bird protection apparatus in the fishway (1) according to claim 5 , the plurality of flexible cords at intervals of approximately half the length of the bird (B) that prey on the fish (F) with its wings spread. Since (3) is stretched, the landing of birds (B) into the fishway (1) can be reliably prevented with a small number.

According to the birdproof device in the fishway (1) according to claim 6 , while connecting the end of the flexible string (3) to the weight rod member (13), the flexible string (3 Since the weight bar member (13) is provided in a suspended form by hanging the position in the vicinity of the weight bar member (13) on the hook bar member (12), the weight bar member (13) is flexible. Even if the flexible string (3) itself is stretched by pulling the elastic string (3), it is possible to always apply tension to the flexible string (3), and to The interval between the sexual cord bodies (3) can be kept constant. Thereby, the approach to the fishway (1) of birds (B) can be prevented effectively.

According to the birdproof device in the fishway (1) according to claim 7 , the weight bar member (13) is suspended from the hooking bar member (12) via the elastic member (14). Only the weight of the weight bar member (13), which is obtained by subtracting the elastic force of the elastic member (14), is applied to the sex string (3). Therefore, the weight bar member (13) is made heavier. This makes it difficult to move, prevents displacement of the flexible string (3), and reduces the tension applied to the flexible string (3). Thereby, durability of a flexible string (3) can be improved.

According to the birdproof device in the fishway (1) according to claim 8 , the slip prevention means (15) for preventing the flexible string (3) from shifting in the parallel direction to the hooking rod member (12). Since it provided, it can prevent that a flexible string (3) slip | deviates from natural situations, such as a wind, and unexpected situations, such as contact of a small animal.

According to the birdproof device in the fishway (1) according to claim 9 , since the flexible string (3) is wound around the hooking rod member (12) more than once, a simple structure, in particular, The shift of the flexible string (3) can be easily prevented without processing the hooking rod member (12) or the like.

According to the birdproof device in the fishway (1) according to claim 10 , the flexible string (3) is provided on the outer peripheral surface of the slip prevention member (40) rotatably supported by the hooking rod member (12). Since the groove (41) that fits is formed, friction of the flexible string (3) can be prevented, deterioration due to wear can be prevented, and durability of the flexible string (3) is improved. Can be made.

  The bird protection device in the fishway of the present invention has realized the purpose of protecting the fish passing through the fishway mainly for going up from the predation of birds by stretching a flexible string above the fishway. .

Figure 1 is Ru plan view showing the fish pass 1 provided on the slope of the river R side on the downstream side of which was built dam D across the river R. FIG. 2 is a side view of the fishway 1 as seen from the river side. FIG. 3 is a side view showing the upper fishway.
First, the structure of the fishway will be described with reference to the drawings.
In Example 1, a commercially available bird-proof yarn 3 ′ is applied to the field as the flexible string 3. The bird-proof thread 3 ′ is for preventing the birds B from landing in the fishway 1. Moreover, this Example 1 applies the single pipe | tube used in order to construct a temporary scaffold at a construction site as a supporting member which supports the flexible string body 3. FIG.

The fishway 1 is connected to the intake channel 4 penetrating the dam D, and is turned back at the upper fishway 1U obliquely descending the slope (slope) on the side of the river R and at the downstream end of the upper fishway 1U. It is composed of a lower fishway 1D that descends diagonally and flows out into the river R, and the place where the intake channel 4 of the upper fishway 1U is connected is the inlet 1in of the fishway 1, and the lower fishway 1D The location connected to the river R is the outlet 1out of the fishway 1.
Although details of the fishway 1 are omitted, normally, the fishway 1 having a width of about 2 m has a flow path formed by connecting stepped weirs, and the weirs are orthogonal to the flow. At the top of the ridge, small cutouts having a length of about 1/3 of the width of the fishway 1 are alternately arranged in a staggered manner. Thereby, the fish F can go up the river water which flows zigzag-like.

Next, a description will be given of a stretch structure of the bird-proof thread 3 'provided above the upper fishway 1U.
As shown in FIG. 1 to FIG. 3, a total of five bird proof threads 3 ′ are prepared, and an upstream support member 10 provided above the inlet 1 in of the upper fishway 1 U of the upper fishway 1 U, and the folded back on the downstream side It is stretched between the downstream support member 11 provided above the portion 1C.
A so-called single pipe is used as the upstream support member 10 and is installed horizontally at a height of about 50 cm from the upper end surface of the side wall 2 constituting the fishway 1 at the inflow port 1 in, and one end of the bird-proof thread 3 ′ is They are connected at regular intervals. The upstream support member 10 is fixed to the dam D by an appropriate means. In addition, a leg portion (not shown) may be used for installing the upstream support member 10 and the leg portion may be installed in the vicinity of the inflow port 1 in, or may be fixed to the tunnel outlet wall surface that constitutes the intake channel 4. Anyway. Alternatively, a handrail or the like above the inlet 1 in provided in the dam D may be used as the upstream support member 10.

FIG. 4 is a perspective view showing the structure of the downstream support member of the upper fishway.
As shown in FIG. 4, the downstream support member 11 includes a hooking rod member 12 that hooks the bird's thread 3 ′, and a weight rod that fastens the tip of the bird's yarn 3 ′ and applies a predetermined tension thereto. The weight bar member 13 is suspended from the hooking bar member 12 via a rubber band 14 '. Further, the other end of the bird-proof thread 3 'is connected to the weight bar member 13, and the weight bar member 13 extends the rubber band 14' while applying tension to the bird-proof thread 3 '. It has become.
In order to make the weight bar member 13 suspended from the hooking bar member 12, the rubber band 14 'is used in the first embodiment. However, the present invention is not limited to this, and the elastic member 14, for example, It may be a coil spring or the like.
The hook member 12 is installed at a height of about 50 cm from the upper end surface of the side wall 2 above the folded portion 1C, which is the downstream end of the upper fishway 1U (see FIG. 3). The hooking bar member 12 has a leg portion (not shown), and the leg portion is placed in the vicinity of the folded portion 1C.

By using the rubber band 14 ', only the weight of the weight rod member 13 obtained by subtracting the elastic force of the rubber band 14' acts on the bird-proof yarn 3 '.
This is because even if the weight of the weight bar member 13 is increased, the bird-proof yarn 3 ′ is not subjected to great tension, and the bird-proof yarn 3 ′ can be made to last longer. That is, when the weight of the weight bar member 13 is reduced, there is a problem that the weight bar member 13 easily moves due to a natural phenomenon such as wind or the contact of a small animal and the bird-proof thread 3 'is displaced. When the weight bar member 13 is made heavy, there is a problem that the tension applied to the bird-proof yarn 3 ′ becomes too large and the durability of the bird-proof yarn 3 ′ is lowered.
Therefore, as in the first embodiment, the weight bar member 13 is suspended from the hooking bar member 12 via the rubber band 14 ', so that the bird's-preventive thread 3' is not excessively tensioned, and It is possible to prevent the bird-proof yarn 3 'from easily shifting.

  The bird-proof thread 3 ′ is wound around the hooking rod member 12 approximately once and a quarter of a turn, and then hung downward and connected to the weight rod member 13. The reason why the bird-proof yarn 3 ′ is wound around the hooking rod member 12 by one turn and ¼ turn is to prevent the bird-proof yarn 3 ′ from being easily displaced in the axial direction of the hooking rod member 12. This structure corresponds to the shift prevention means 15 in the claims (claim 9). Thereby, the bird-proof thread 3 ′ is not easily displaced by a natural phenomenon such as wind or the contact of a small animal, etc., and the plurality of bird-proof threads 3 ′ arranged side by side can keep the distance from each other constant. it can. Moreover, the slip prevention means 15 can be realized easily and inexpensively without using a special member.

  As the bird-proof yarn 3 ', in addition to the bird-proof yarn (commercial twisted yarn) as in the first embodiment, so-called tegus, kite yarn, glass fiber, string, rope, wire, metal yarn, etc. may be used. However, considering simplicity and the like, those made of synthetic resin are preferable. The bird-proof yarn 3 'used for this is a silver yarn twisted. Also, the fishing line is transparent and glitters when exposed to light, and the birds B are optimal because they have a habit of being wary of such shiny objects.

  Further, since the single pipe is used as the support member for supporting the bird-proof yarn 3 'in the first embodiment, the above-described support member can be produced at a low cost. The support member in the present invention is not limited to a cylindrical pipe-shaped member such as a single tube, but may be a pipe-shaped member having a polygonal cross-section, or may be a solid member without being limited to a pipe shape. . Further, the material is not limited to iron such as a single tube, but may be other metal materials or synthetic resin materials. The weight support member preferably has a high specific gravity to some extent.

FIG. 7 is a longitudinal sectional view of the fishway.
As shown in FIG. 7, on the upper fishway 1U, five birdcage threads 3 'are stretched at an interval of about 50cm above the upper fishway 1U. It is located above the side wall 2 which comprises. The reason why both the distance between the bird-proof yarns 3 'and the height from the fishway 1 is about 50 cm is that the birds B that prey on the fish F have a large number of herons (Storciformae). That is, the heron body length is about 60-90cm, the length of the wings is about 100cm, and if the pitch of the bird's-prevention thread 3 'is about 50cm, This is because it can be brought into contact with the bird-proof yarn 3 '. Therefore, even if a bird B such as a heron tries to land on the upper fishway 1U or stops on the side wall 2 of the upper fishway 1U, it cannot be landed because it always comes in contact with the bird's thread 3 '. The fish F that runs up the upper fishway 1U is not preyed on by these.

FIG. 5 is a side view showing a bird-proofing device for a lower fishway, where the water level of the river is in a normal state. FIG. 6 is a side view showing the bird protection device in the lower fishway, showing a state where the water level of the river has risen.
Next, the tension structure of the bird-proof thread 3 ′ provided above the lower fishway 1 </ b> D will be described with reference to FIGS. 5 and 6. The tensioning structure of the bird's thread 3 'differs from the tensioning structure of the upper fishway 1U described above in that a hooking bar member 12 and a weighting bar member 13 are provided as the upstream side support member 20. The downstream support member 21 is a rod-like member to which one end of the bird-proof yarn 3 ′ is connected, and the downstream support member 21 is installed so as to be movable up and down by the lifting means 22. Therefore, in the description of the lower fishway 1D, the difference from the upper fishway 1U is mainly performed, and the other parts are denoted by the same reference numerals and the description thereof is omitted.

As described above, the support member 20 on the upstream side of the lower fishway 1D is a hook member 12 for hooking the bird's thread 3 'and a weight for fastening the tip of the bird's thread 3' to give a predetermined tension thereto. The weight bar member 13 is suspended from the hooking bar member 12 via a rubber band 14 '.
The points of winding the bird-proof yarn 3 ′ around the hooking rod member 12 and ¼ turn and the point of connecting one end of the bird-proof yarn 3 ′ to the weight rod member 13 are shown in the upper row. It is the same as the fishway 1U. Note that the hooking rod member 12 or weight rod member 13 of the upstream support member 20 of the lower fishway 1D and the hooking rod member 12 or weight rod member 13 of the downstream support member 11 of the upper fishway 1U are 1 It can also be used as a long bar member. However, when the weight rod member 13 is used in common, it differs depending on whether the bird-proof thread 3 'in the upper fishway 1U and the bird-proof thread 3' in the lower fishway 1D are pulled upward or downward, and the upper fishway 1U. Since the tension of the bird-proof thread 3 ′ is different between the side and the lower fishway 1 </ b> D side, it is preferable not to share the weight bar member 13.

The downstream side support member 21 of the lower fishway 1D is composed of a rod-like member that connects one end of the bird-proof thread 3 ', and a rope 22' serving as lifting means 22 is connected to both ends thereof, and the other end of the rope 22 'is connected. Is connected to the handrail 23 of the dam D located above. As a result, the downstream support member 21 is suspended from the handrail 23 via the rope 22 'and is supported at a height of about 50 cm on the downstream side of the lower fishway 1D. The rope 22 'lifts the downstream support member 21 by pulling the rope 22' from the handrail 23 side of the dam D, and lowers the downstream support member 21 by returning the handed rope 22 'to its original position. And can function as the elevating means 22.
In addition, as the raising / lowering means 22 which raises / lowers such a downstream side support member 21, automation is aimed at, the downstream side support member 21 is raised in response to discharge | release of the dam D, or the water level of the river R is detected. The downstream support member 21 may be raised using this as a trigger.
Since the downstream support member 21 is supported by the rope 22 'as the lifting means 22 and can be appropriately lifted and lowered, for example, when the dam D is discharged, the downstream support member 21 and the bird protection thread 3' are submerged. Can be prevented. That is, when the water level of the river R rises when the dam D is discharged, the downstream support member 21 and the bird's-prevention yarn are preliminarily moved by retracting the rope 22 'and retracting the downstream support member 21 upward. 3 'is not flooded (see FIG. 6). Thereby, it can prevent that these are poured into the river R at the time of the discharge of the dam D, or garbage etc. are caught on these.

  In the bird-proofing device in the fishway 1 of the first embodiment, since the plurality of bird-proofing yarns 3 ′ are arranged side by side so as to extend in the longitudinal direction of the fishway 1, the length per one of the bird-proofing yarns 3 ′. However, since the support members 10, 11, 20, and 21 can be shortened and the number of connection points with these members can be reduced, workability and maintenance can be improved.

Figure 8 is a view to a perspective view of Botori device in fishway 1 of Example 2. FIG. 9 is a front view of a main part showing a construction for extending the bird-proof thread 3 ′ that is installed above the fishway 1.
In the second embodiment, a V-shaped groove 32 is excavated in the hooking bar member 12 as the shift prevention means 15 for preventing the shift of the bird-proof yarn 3 'in the juxtaposed direction.
The V-groove 32 formed in this way has an opening width that is slightly larger than the diameter of the bird-proof yarn 3 ′, and is formed in such a size that the bird-proof yarn 3 ′ fits almost completely. As a result, even when a force in the juxtaposition direction is applied to the bird-proof yarn 3 ′, it cannot easily get over the V-groove 32, thereby preventing displacement. Such a groove is not limited to the V-groove 32 but may be a concave groove or a U-groove. In short, it is only necessary that the bird-proof yarn 3 'can be prevented when it moves in the juxtaposition direction. Further, the V-groove 32 is not limited to the one excavated in the hooking rod member 12, and a groove may be formed at the top of the annularly raised portion.
Therefore, in the bird-proofing device in the fishway 1 of the second embodiment, it is possible to realize the prevention of deviation of the bird-proofing yarn 3 ′ reliably arranged in parallel with a simple structure.

Figure 10 is a view to a perspective view of Botori device in fishway 1 of Example 3. FIG. 11 is a front view of a main part showing a structure for extending the bird-proof thread 3 ′ extended above the fishway 1.
In the third embodiment, as the slip prevention means 15 for preventing the slip in the side-by-side arrangement of the bird-proof yarns 3 ′, a V-groove is formed on the outer peripheral surface of an annular slip prevention member 40 that is rotatably supported by the hooking rod member 12. 41 is formed.
The V-groove 41 is formed in such a size that the opening width is larger than the diameter of the bird-proof yarn 3 ′ and the bird-proof yarn 3 ′ fits almost completely like the V-groove 32 of the second embodiment described above. Yes.
Further, such a slip prevention member 40 is rotatable with respect to the hooking rod member 12, but the hooking rod member 12 is formed with ridges 42, 42 so as to prevent movement in the axial direction. These ridges 42 are rotatably supported.
Thus, when the bird-proof thread 3 ′ hooked on the slip-preventing member 40 moves in the length direction, the slip-preventing member 40 rotates with respect to the hooking rod member 12, and thus the slip-preventing thread 3 ′ and slip-preventing are prevented. Friction does not occur with the member 40, and therefore it is possible to prevent the birdcage yarn 3 'from being worn.

FIG. 12 is a perspective view of a main part showing a basic structure of a bird-proofing device in the fishway 1 of Example 4 and showing a construction for extending a bird-proofing thread 3 ′ stretched above the fishway 1.
In the fourth embodiment, the construction for extending the bird's thread 3 'to be installed above the fishway 1 is extremely simplified, and the cost is reduced.
One support member 50 is installed on the upstream side of the fishway 1, and one support member 51 is installed on the downstream side. The upstream support member 50 and the downstream support member 51 are connected to the bird-proof yarn. 3 'ends are connected to each other.
Thereby, the bird-proof thread 3 'can be stretched so as to extend in the longitudinal direction above the fishway 1, and the landing of the birds B on the fishway 1 can be prevented as in the first embodiment.
Further, when installing the bird-proof yarn 3 ′, only the upstream support member 50 and the downstream support member 51 are necessary, so that the cost of the tension structure can be reduced.
In addition, when the bird-proof yarn 3 'is connected to the support members 50 and 51, pulling the bird-proof yarn 3' so that the bird-proof yarn 3 'is tensioned to some extent causes a reaction that is received when birds come into contact with the bird-proof yarn 3'. It is also useful for preventing yarn contact and twisting and aesthetics.

  In each of the above embodiments, the flexible string body is stretched in the longitudinal direction of the fishway. However, the present invention is not limited to this, and is stretched in a direction orthogonal to the longitudinal direction of the fishway or in an oblique direction. Also good.

As described above, according to the bird protection apparatus for a fishway of the present invention, it is possible to prevent birds such as herons from flying and landing on the fishway with a simple structure. Can be effectively protected from predation.
Of course, the shape of the fishway of the present invention, the flexible string, its mounting position, etc. can be changed as appropriate without departing from the spirit of the invention.

  In each of the above-described embodiments, the fishway attached when the dam is constructed has been described as a representative example. Applicable to fishways that pass through when descending.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of an entire birdproof device in a fishway according to Example 1; It is the whole side view. It is the side view which showed the upper stage fishway. It is a perspective view which shows the structure of the downstream support member of an upper stage fishway. It is the side view which showed the bird protection device of a lower fishway, and the water level of a river shows a normal state. It is the side view which showed the bird protection apparatus in a lower fishway, and shows the state which the water level of the river rose. It is a longitudinal cross-sectional view of a fishway. It is a perspective view which shows the structure of the downstream support member of the bird-proof apparatus in the fishway of Example 2. FIG. It is a front view which shows the deviation | shift prevention means of the bird-proof apparatus in the fishway of Example 2. FIG. It is a perspective view which shows the structure of the downstream support member of the bird-proof apparatus in the fishway of Example 3. FIG. It is a front view which expands and shows the shift | offset | difference prevention means of the bird protection apparatus in the fishway of Example 3. It is a perspective view which cuts off a part of upstream support member and downstream support member of the bird-proofing device in the fishway of Example 4, and is shown.

R River D Dam F Fish B Birds 1 Fishway 1U Upper fishway 1in Inlet 1D Lower fishway 1out Outlet 1C Folding part 2 Side wall 3 Flexible string 3 'Birdproof thread 4 Intake channel (dam)
DESCRIPTION OF SYMBOLS 10 Upstream side support member 11 Downstream side support member 12 Hooking bar member 13 Weight bar member 14 Elastic member 14 'Rubber band 15 Misalignment prevention means 20 Upstream side supporting member 21 Downstream side supporting member 22 Lifting means 22' Rope 23 Handrail 32 V-groove 40 slip prevention member 41 V-groove 42 ridge 50 upstream support member 51 downstream support member

Claims (10)

A bird protection device in a fishway (1) installed to allow fish (F) to pass through,
Upstream provided on the upstream side of the fishway (1) so that the wings or body of the bird (B) comes into contact with the bird (B) flying for predation when landing in or near the fishway (1) Between the side support member (10, 20, 50) and the downstream support member (11, 21, 51) provided on the downstream side, a plurality of flexible string bodies (3) are attached to the fishway (1). A bird-proof device for a fishway, characterized by being stretched upward. Fishway to (1) river outlet to be connected to (R) the downstream support member (21) lifting means Ru is lifting a provided above the (1out) (22) of, provided in the flow outlet (1out) , Botori device in fishway of claim 1, wherein the. Fishway (1) more alongside stretched by flexible cords in the width direction of at least one of (3), disposed above the side wall (2) constituting the fishway (1), that Botori device in fishway according to claim 2 1 or claim 2, wherein. The distance between the upper surface of the side wall (2) constituting the fishway (1) and the flexible string (3) stretched above the fish (1) is set so that the bird (B) does not stop on the side wall (2). narrow Kushida than the total height of the target birds (B) of the birds (B) which prey (F), Botori device in fishway of claim 3, characterized in that. The plurality of flexible string bodies (3) are stretched so that the birds (B) that prey on the fish (F) are spaced approximately half the length of the spread wings. The bird-proof apparatus in the fishway in any one of Claim 1 thru | or 4 . The downstream support member (11) or the upstream support member (20) includes a hooking rod member (12) for hooking the stretched flexible string (3), and the flexible string (3). A weight bar member (13) for applying tension;
The end of the flexible string (3) is connected to the weight bar member (13), and the position of the flexible string (3) in the vicinity of the weight bar member (13) is set to the hook bar. by multiplying the member (12), provided in the form hanging weights for bar members (13), Botori device in fishway according to any one of claims 1 to 5, characterized in. Botori device in fishway according to the weight for the rod member (13), said the hook for the rod member (12) hung through the elastic member (14), that in claim 6, wherein. Wherein the hook for the rod member (12), the flexible cords (3) is provided with displacement prevention means (15) to prevent the displaced in parallel directions, that to claim 6 or claim 7, characterized in Bird protection equipment on the described fishway. 9. The fishway according to claim 8 , wherein the slip prevention means (15) has a structure in which the flexible string (3) is wound around the hooking rod member (12) at least once. Birdproof device. The slip prevention means (15) is a slip prevention member (40) rotatably supported by the hooking rod member (12), and the slip prevention member (40) has a flexible string ( 3) has a structure V grooves (41) formed to be fitted, Botori device in fishway of claim 8, characterized in that.