JP2004298125A - Trawling net having grading functionality - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To separate small-sized fishes which are same kinds as fishes to be caught or different kinds from the fishes to be caught and are smaller than sizes of fishes to be caught from the fishes to be caught in the sea before fish haul and return these small-sized fishes to sea. <P>SOLUTION: This trawling net has a main net 4 having an opening 5 and formed in a bag shape, three separation openings 11 formed in the main net 4, an outer net 12 arranged so as to oppose a face on sea of the main net 4 along the edge of a netentering part 8 in the openings 11 for each separation on sea bottom side of the main net 4 and a pocket net 16 arranged between the main net 4 and the outer net 12 and constituting a passage connecting from the periphery of openings 11 for each separation to the rear end of the outer net 4 between the main net and the outer net 12. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
TECHNICAL FIELD The present invention relates to a dragnet with a sorting function used for dragnet fishing such as bottom dragnet fishing or boat dragnet fishing.
[0002]
[Prior art]
Conventionally, as one type of fishing method of catching fish, bottom dragnet fishing in which a dragnet is pulled on the seabed by a boat to capture fish on the seabed, or fish such as middle layer by dragging the dragnet on the middle or surface layer of the sea. There is known a dragnet fishing method such as a dragnet fishing for capturing.
[0003]
The dragnet used in the dragnet fishing method generally has a bag-shaped body net having an opening, and a pair of draglines is connected to both side edges of the opening.
[0004]
When this dragnet is used for bottom dragnet fishing, a plurality of floats are provided at the edge of the opening at the sea surface side, and a weight such as a chain is provided at the edge of the opening at the seabed side. Is done. When one end of each of the tow ropes in this towing net is towed by a ship, the seafloor edge of the opening of the body net is crawled on the seafloor, and the seaside edge of the opening is seafloor by each float. The body net can be moved on the seabed while floating on the seabed to widen the opening. Then, the fish on the seabed was captured using the drag net by causing the fish on the seabed to enter the inside of the body net through the opening.
[0005]
[Problems to be solved by the invention]
However, when catching fish using a dragnet in the dragnet fishing, if the body net is moved underwater, not only fish of the size or type to be captured but also fish near the opening of the body net Of fishery, which is not desirable for protection of fishery resources.
[0006]
For this reason, from the viewpoint of protection of the fishery resources, it is also performed to select and return, for example, small fish different in size or type of fish to be captured from the captured fish to the sea. I have. However, it is troublesome to select fish that are not to be captured from among the captured fish, and even if the fish can be selected, fish that have been landed once are weakened, and it is difficult to return them to the sea.
[0007]
The present invention has been made in view of these points, prior to landing in the sea, fish of the same type or different types of fish to be captured and smaller than the size of the fish to be captured, It is an object of the present invention to provide a seine net with a sorting function that can be sorted from fish and returned to the sea.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, a towing net with a sorting function according to the present invention according to claim 1, comprises a body net formed in a bag shape having an opening, and at least one sorting opening formed in the body net. Part, an outer net arranged outside the body net along an edge of the sorting opening on the opening side and facing the outer surface of the body net; the body net and the outer net And a passage formed between the body net and the outer net, from the peripheral edge of the sorting opening to the other edge of the outer net opposite to the edge of the outer net on the opening side. And a pocket net.
[0009]
According to the first aspect of the present invention, when the fish enters the body net from the opening and reaches the sorting opening, the fish to be captured is the sorting opening and the sorting opening. Recognizing the pocket net connected to the peripheral edge of the opening, and moving inward of the body net to escape from the pocket net. As a result, the fish to be captured is guided to the far side inside the body net. On the other hand, a fish smaller than the fish to be captured does not recognize the sorting opening and the pocket net, and thus can escape from the sorting opening to the outside of the body net. Thereby, the towing net with a sorting function can select fish to be captured in the sea from smaller fish, and return these small fish to the sea.
[0010]
The towing net with a sorting function according to the second aspect of the present invention is characterized in that the opening for sorting is formed on a surface of the body net on the seabed side.
[0011]
Furthermore, the drag net with a sorting function according to the invention of claim 3 is characterized in that the opening for sorting is formed at a part of an edge of the opening.
[0012]
According to the second and third aspects of the present invention, when a fish that inhabits the seabed such as flounder arrives at the opening for sorting while trying to enter the inside of the body net through the opening, the fish to be captured is taken. Recognizes the sorting opening and the pocket net connected to the periphery of the sorting opening, and floats to escape from the pocket net, and as a result, moves to the inner side of the body net. On the other hand, a fish smaller than the fish to be captured does not recognize the sorting opening and the pocket net, and thus can escape from the sorting opening to the outside of the body net. Thereby, the towing net with a sorting function can select fish to be captured in the sea from smaller fish, and return these small fish to the sea.
[0013]
Still further, the drag net with a sorting function according to the invention of claim 4 is arranged such that a float is provided inside the body mesh and at a portion of the edge of the sorting opening on the back side of the body mesh. A weight is provided at an edge of the sorting opening on the opening side.
[0014]
According to the invention as set forth in claim 4, the portion of the body net at the edge of the sorting opening is floated in the sea by the float, and the opening in the sorting opening is caused by the weight. The edge on the side can be brought into contact with the seabed, whereby the sorting opening can be reliably opened in the sea.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of a dragnet with a sorting function according to the present invention will be described with reference to FIGS. 1 to 3. Here, in this embodiment, a bottom seine used for flatfish fishing as a seine net will be described.
[0016]
FIG. 1 is a perspective view showing an embodiment of a seine net with a sorting function according to the present embodiment. As shown in FIG. 1, the seine net 1 with a selective function has a substantially conical shape and a circular surface. And a body net 4 having a pair of sleeve portions 3 extending along both sides of the opening edge of the bag portion 2 along the substantially conical slope. A peripheral portion from the opening edge of the bag portion 2 to the edge portion of each of the sleeve portions 3 is an opening portion 5 of the body net 4.
[0017]
Further, a plurality of floats 7 are disposed on the sea surface side peripheral edge of the opening 5, while the seafloor side peripheral edge of the opening 5 corresponds to the opening edge of the bag portion 2. A weight 9 made of a chain or the like is provided in the incoming net portion 8. Then, the peripheral portion of the opening 5 on the sea surface side is lifted to the sea surface side by the buoyancy of each of the floats 7, and the mesh portion 8 of the opening 5 comes into contact with the seabed by weight, so that the body net 4 is formed. The opening 5 opens in the sea.
[0018]
Further, a plurality of (three in this embodiment) sorting openings 11 having a pointed shape are formed in the bag portion 2 toward the back side of the bag portion 2 along the mesh portion 8. The opening width of the leading edge of each of the sorting openings 11 is formed by an opening width dimension that enables a large fish to be captured to be recognized and a small fish that is not to be captured to be unrecognizable. I have. The shape and the number of the sorting openings 11 are not limited to those of the present embodiment.
[0019]
As shown in FIGS. 2 and 3, a quadrangular outer net 12 is disposed on the bottom surface of the body net 4 so as to face a part of the bottom surface of the body net 4. The outer edge of the outer net 12 is connected to the entrance portion 8 in the opening 5 of the body net 4. The outer net 12 has a rear end edge of the outer net 12 formed by the tension ropes 13 arranged in the gap between both ends of the rear edge facing the front edge and the seabed side surface of the body net 4. The net 4 is located at a predetermined gap size from the surface on the seabed side. In addition, a weight 14 made of a chain or the like is provided at a peripheral portion of the outer net 12, so that the outer bottom surface of the outer net 12 is in contact with the sea bottom.
[0020]
Further, between the body net 4 and the outer net 12, a plurality of pocket nets 16 each having a square shape with an acute angle are disposed, and each of the pair of pocket nets 16 is provided with each of the sorting openings. A plurality of passages are formed from the periphery of the portion 11 to the rear end portions of the body net 4 and the outer net 12. More specifically, one of the pocket nets 16a of the pair of pocket nets 16 has the acute-angled portion in contact with the net entry portion 8 in the opening 5 of the body net 4, and one side of each of the pocket nets 16a is used for the sorting. The opening 11 is connected to one side adjacent to the leading edge, the side adjacent to one side of each pocket net 16a is connected to the seabed side surface of the body net 4, and one side of each pocket net 16a. Is connected to the surface of the outer net 12 on the sea surface side. The other pocket net 16b of the pair of pocket nets 16 has the acute-angled portion in contact with the net entry portion 8 in the opening 5 of the body net 4, and one side of each of the pocket nets 16b has each of the sorting openings. The part 11 is connected to the other side adjacent to the leading edge, the side adjacent to one side of each pocket net 16b is connected to the seabed side surface of the body net 4, and one side of each pocket net 16b. Is connected to the surface of the outer net 12 on the sea surface side. The rear ends of the pocket nets 16a and 16b are open.
[0021]
Specifically, in the present embodiment, the outer net 12 is formed such that the width dimension of the leading edge and the trailing edge is 4.0 m, and the length dimension is 3.5 m. In addition, each of the sorting openings 11 has an opening width dimension of a front end edge of 1.2 m, and a dimension of each side adjacent to the front end edge is 1.33 m.
[0022]
Furthermore, inside the body net 4 and at a position corresponding to the rear side of the body net 4 and the rear end of each pocket net 16 at the edge of each of the sorting openings 11, Floats 19 and 20 are provided. As a result, the portion of the body net 4 at the edge of each of the sorting openings 11 floats in the sea by the floats 19 and the weight 9 enters the net 5 in the opening 5 of the body mesh 4. Since the portion 8 comes into contact with the seabed, each of the sorting openings 11 is opened in the sea. Further, a portion corresponding to the rear end of each of the pocket nets 16 in the body net 4 is floated in the sea by each of the floats 20, and the outer net 12 is in contact with the seabed by the weight 14, so that each of the passages 17 is open in the sea. Thereby, the inside of the body net 4 passes through the passages 17 through the respective sorting openings 11 and communicates with the outside of the body net 4.
[0023]
In addition, one tow rope 23 is connected to the tip end of each of the sleeves 3 in the body net 4 via two ropes 21 respectively, and the other end of each tow rope 23 is It is connected to a fishing boat (not shown).
[0024]
The towing net 1 with the sorting function pulls each of the towing lines 23 by the fishing boat, so that the fish on the seabed enters the inside of the body net 4 from the opening 5 of the body net 4, It is designed to catch fish.
[0025]
Next, the operation of the drag net 1 with a sorting function will be described.
[0026]
First, when each towing line 23 is pulled by a fishing boat, each of the sleeves 3 of the body net 4 is pulled by the towing line 23, and the body net 4 moves the periphery of the sea surface side of the opening 5 in the sea. The floating member 7 is lifted up, and the net portion 8 in the opening 5 is brought into contact with the seabed by weight to move while opening the opening 5.
[0027]
Then, flatfish and the like on the seabed enter the body net 4 from the opening 5. At this time, when the large flounder to be captured reaches each of the sorting openings 11 at the mesh portion 8 in the opening 5, each pocket net connected to one side of the sorting opening 11 due to the habit of the flounder. In order to escape from each of the pocket nets 16 upon recognizing the pocket network 16, the user floats. As a result, the large flounder enters the interior of the body net 4 at the back. On the other hand, a small flounder or a fish of a different type smaller than the fish to be captured and having a width smaller than the width of the large flounder will reach the respective sorting openings 11 even if the respective pocket nets 16 reach the respective sorting openings 11. Is not recognized, it is possible to get out of the body net 4 through the passages 17.
[0028]
As described above, according to the present embodiment, a large flounder having a size to be captured can be guided toward the back of the inside of the body net 4, and it is smaller than the maximum width dimension of the small flounder or the other large flounder. Different types of fish having small widths can be pulled out of the body net 4, and the large flounder can be selected from the small flounder or the like in the sea.
[0029]
Therefore, it is possible to prevent indiscriminately and in large quantities capturing other small flounders and other small fish that are not large flounders to be captured, and as a result, it is possible to protect fishery resources.
[0030]
Note that the present invention is not limited to the above embodiment, and can be variously modified as needed.
[0031]
For example, in the present embodiment, the selection opening 11 is formed along the entrance portion 8 in the opening 5 of the body net 4, but is not limited to this.
[0032]
Further, the shape of the body net 4 is not limited to the shape in the present embodiment.
[0033]
Furthermore, in the present embodiment, the case of flatfish fishing using the bottom drag net as the dragnet 1 with the sorting function has been described, but the present invention is not limited to this, and bottom dragnet fishing and boat dragnet fishing of different fish species are used. It can also be used for other purse seine fishing.
[0034]
【The invention's effect】
As described above, according to the towing net with a sorting function according to the invention described in claim 1, claim 2, and claim 3, the fish to be captured and the smaller fish are sorted in the sea, Since the small fish can be returned to the sea as they are, it is possible to prevent indiscriminate and large-scale catching of fish, and as a result, it is possible to protect fishery resources.
[0035]
Further, according to the drag net with the sorting function according to the invention of claim 4, since the opening for sorting can be reliably opened, the fish smaller than the fish to be captured can be more easily opened. From the body to the outside of the body net. As a result, the seine net with the sorting function can protect fishery resources by more reliably returning fish smaller than the fish to be captured to the sea.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment of a towing net with a sorting function according to the present invention; FIG. 2 is an enlarged view showing a sorting net arranged in the towing net with sorting function in FIG. 1; FIG. Sectional view of AA showing the seine net with sorting function 1
DESCRIPTION OF REFERENCE NUMERALS 1 Sewing net with sorting function 4 Body net 5 Opening 8 Entrance part 11 Sorting opening 12 Outer net 13 Tension rope 14 Weight 16 Pocket net 17 Passage 23 Tug rope

Claims (4)

A body net formed in a bag shape having an opening,
At least one sorting opening formed in the body net;
An outer net arranged outside the body net along the edge on the opening side of the sorting opening and facing the outer surface of the body net,
The other is disposed between the body net and the outer net, and faces the edge of the outer net on the opening side from the peripheral edge of the selection opening between the body net and the outer net. A drag net having a sorting function, comprising a pocket net constituting a passage leading to an edge. 2. The drag net according to claim 1, wherein the sorting opening is formed on a surface of the body net on the seabed side. 3. The said segregation opening part was formed in a part of edge part in the said opening part, The seine net with a selection function of Claim 2 characterized by the above-mentioned. Inside the body net, a float is provided at a portion of the edge of the sorting opening on the back side of the body net, and a weight is provided at an edge of the sorting opening on the opening side. The drag net having a sorting function according to claim 2 or 3, wherein the drag net is provided.

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