JP3950884B2 - Fish egg collector - Google Patents

Description

  The present invention relates to a fish egg collector for collecting eggs laid by, for example, cultured fish.

  In recent years, conservation of natural resources has been advocated in all fields, and fisheries that depend on sea, river, and lake resources have also been tried for aquaculture, which is a shift from catching fisheries to cultivating fisheries. Even in the aquaculture industry, all processes are important in complete aquaculture through the process of egg collection, fertilization, hatching, fry and adult fish. However, since there is no egg to grow as a fish, complete aquaculture is not possible, so the egg collection process Is important.

  Egg collection is relatively easy when it can be extracted from the belly of a parent fish, such as a salmon, but depending on the type of fish, it is often necessary to collect eggs laid naturally. Eggs naturally spawned from parent fish may be eaten by adult fish unless they are collected quickly after spawning, and the hatching rate after fertilization decreases.

  As a prior art corresponding to such a problem, a fish tank for egg collection that can prevent eggs laid by an adult fish from being eaten and efficiently collect eggs is proposed (see Patent Document 1). . In Patent Document 1, it is possible to take out an egg that has passed through the bottom of the slanted bottom surface and gathered to the outside, and a partition plate that allows eggs to pass through the aquarium main body but not adult fish. By providing a passage for egg collection, prevention of eating by adult fish and efficient collection are realized.

  However, since Patent Document 1 is intended for a small ornamental fish that can be accommodated in an aquarium, such as a zebrafish, it can be cultured only in a large space such as a ginger, for example, a large fish such as a bluefin tuna. It is impossible to use a fish tank for egg collection like Patent Document 1. Bluefin tuna always swims in a vast underwater space at high speed, so a huge aquarium is required to accommodate bluefin tuna. If an aquarium capable of accommodating such bluefin tuna is prepared, the equipment cost becomes huge, so it is quite unrealistic to apply a fish tank for egg collection to bluefin tuna.

  When targeting fish cultivated in a vast space such as a ginger, first, the fish behavior in the ginger provided on the sea, such as tracking behavior and spawning behavior, is visually observed over several hours, and the fish is also screened. Combined with scooping up and observing the fish to estimate the spawning time, we are collecting eggs when spawning behavior is observed.

  Spawning of fish is often performed at night, and even if it is carried out by hand and visually observed for several hours at night, there is not always spawning behavior, so it is forced to waste a great deal of human labor The fact is. Therefore, there is a strong demand for easily confirming that the cultured fish has laid eggs without requiring human labor.

JP 2001-120110 A

  An object of the present invention is to provide a fish egg collecting tool that can easily confirm that a cultured fish has laid eggs without requiring manual labor.

The present invention is a fish egg collector for collecting eggs laid by fish in water,
A collecting member having an opening formed at one end and the other end so as to converge from one end toward the other end, and a weight on one end side It is a net that is fitted with a member and opens in a conical shape with one end side in the vertical direction being the lower side in the vertical direction. A collecting member to collect;
A passage hole through which the fish egg passes is formed at one end, and is attached to the collection member so as to communicate with the opening formed at the other end of the collection member, and is captured by the collection member. A storage container for storing collected fish eggs;
It is a fish egg collector characterized by including the floating member with which it attaches to a storage container and has buoyancy with respect to water.

Further, the present invention is characterized in that the mesh opening is 400 μm or more and 1000 μm or less.
In the present invention, the container is made of a transparent material.

  According to the fish egg collecting device of the present invention, the eggs laid in the water by the fish and floating are collected by the collecting member, and the water surface is collected by the floating member through the opening at the other end of the collecting member. It is stored in a storage container that floats on the part. Therefore, it is possible to easily determine the presence or absence of spawning behavior by a fish simply by placing a fish egg collector in the cage where the cultured fish is located and observing the presence or absence of the egg in the container after a predetermined period of time. This makes it possible to save labor for visually observing fish behavior.

  Further, according to the present invention, since the collecting member is composed of a net having a weight member attached to one end side and opening in a conical shape with one end side being a lower side in the vertical direction in water, For example, a blue-fin tuna egg uses the property that it floats in seawater, and without using a special device, a fish egg that has entered the net is converted into a conical bottom on one end side. It is possible to move from the side to the receiving container that is mounted on the other end side and located on the water surface by the floating member.

  Further, according to the present invention, the mesh opening is 400 μm or more and 1000 μm or less, so that, for example, bluefin tuna eggs can be reliably collected.

  Further, according to the present invention, since the storage container is made of a transparent material, it is possible to easily determine whether or not fish eggs are collected in the storage container without removing the storage container.

  FIG. 1 is a perspective view showing a simplified configuration of a fish egg collector 1 according to an embodiment of the present invention. The fish egg collector 1 is formed such that openings 4 and 5 are formed at one end 2 and the other end 3 so as to converge from one end 2 toward the other end 3. A collecting member 6 that collects the fish eggs 7 that are formed so as to allow water to pass therethrough and not pass the fish eggs 7 and float in the water, and a fish egg at one end. 7 is formed, and is attached to the collecting member 6 so as to communicate with the opening 5 formed in the other end 3 of the collecting member 6. A storage container 9 for storing the fish eggs 7 to be collected and a floating member 10 attached to the storage container 9 and having buoyancy with respect to water are included.

  The floating member 10 is formed to have a ring shape in the present embodiment. The material of the floating member 10 is not particularly limited as long as it has buoyancy with respect to water, and foamed polystyrene or the like is preferably used. The container 9 is disposed in the central gap portion of the floating member 10 having a ring shape.

  The container 9 has a bottomed cylindrical shape, an opening is formed on the opposite side of the bottom, and the opening constitutes the passage hole 8. The material of the container 9 is preferably transparent, and may be colorless and transparent or colored and transparent as long as it is transparent. Although it does not specifically limit as a raw material of the storage container 9, For example, a polyethylene terephthalate, an acrylic resin, etc. are mentioned.

  The storage container 9 has the passage hole 8 facing downward in the vertical direction, and is disposed in the central gap portion of the floating member 10 as described above. The floating member 10 is attached to the storage container 9 by the attachment member 11. In the present embodiment, the mounting member 11 is composed of a rope. The floating member 10 is attached to the storage container 9 by catching the floating member 10 with the rope 11 and fixing the opposite end to the storage container 9. In addition, the rope which is the attachment member 11 attaches the floating member 10 to the storage container 9 at a plurality of locations (four locations in the present embodiment).

  In the present embodiment, the collection member 6 is a net that has a weight member 12 attached to one end 2 side thereof and opens in a conical shape with the one end 2 side being a lower side in the vertical direction in water. The material of the net constituting the collecting member 6 is not particularly limited, but for example, a plankton net made of polyamide synthetic fiber is preferably used. Further, the mesh opening may be set as appropriate according to the size of the fish egg to be collected, as long as the conditions for allowing water to pass and not allowing the fish egg to pass are satisfied. However, when the collection target is, for example, a bluefin tuna egg, the size of the bluefin tuna egg is approximately 1.0 mm. Therefore, the opening is preferably 400 μm or more and 1000 μm or less.

  A weight member 12 is attached to a portion of the collecting member 6 that forms the opening 4 at one end 2. As the weight member 12 of this embodiment, one having a ring shape is used. The weight member 12 is preferably made of a material having a specific gravity greater than seawater and having good corrosion resistance when immersed in water, such as stainless steel.

  The net constituting the collection member 6 is provided with a ring-shaped weight member 12 at one end portion 2 and a receiving container 9 with a floating member 10 attached at the other end portion 3. When 1 is thrown into the water, it is suspended in the water with the one end 2 side being the lower side in the vertical direction, and opens into a conical shape, more precisely a truncated cone shape. In the fish egg collector 1 of the present embodiment, the height h of the collecting member 6 when suspended in water is about 1 m, and the diameter d of the opening 4 at the one end 2 of the collecting member 6 is about 1 m. 60 cm.

  When the fish egg collector 1 configured in this way is introduced into the ginger sea to collect, for example, bluefin tuna eggs, the collector 6 hangs down into the seawater and opens into a conical shape. The collector 1 floats in seawater due to the buoyancy of the floating member 10 while holding the container 9 near the sea surface. The fish egg collector 1 floating in the seawater moves along the flow of seawater generated in the vicinity of the sea surface by the sea breeze and the sea breeze.

  On the other hand, when the bluefin tuna in the ginger lays eggs, good quality eggs are floated in the seawater. Move. Since the fish egg collector 1 and the spawned egg behave in the same manner, the spawned egg has an opening 4 at one end 2 of the collecting member 6 of the fish egg collector 1 during the ascent process. And is further levitated in the collecting member 6 and passes through the opening 5 and the passage hole 8 of the other end 3 and is accommodated in the accommodating container 9.

  Therefore, the fish egg collector 1 is put into the sacrifice during the bluefin tuna laying time, for example, from 17:00 to 21:00. After a predetermined time has passed, the fish eggs are visually recognized in the container 9 made of a transparent material. It is possible to determine whether or not bluefin tuna has been laid.

  This eliminates the need for manually observing the tracking behavior, the spawning behavior, etc. to confirm the spawning, and the fish catcher 1 is put in the cage for a predetermined time, and then the container 9 The egg laying can be confirmed by a simple and labor-saving means of visually observing the presence or absence of the fish eggs inside.

It is a perspective view which simplifies and shows the structure of the fish egg collector 1 which is one Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fish egg collection tool 2 One edge part 3 The other edge part 4,5 Opening part 6 Collection member 7 Fish egg 8 Passing hole 9 Storage container 10 Floating member 11 Mounting member 12 Weight member

Claims (3)

In a fish egg collector that collects eggs laid in water by fish,
A collecting member having an opening formed at one end and the other end so as to converge from one end toward the other end, and a weight on one end side It is a net that is fitted with a member and opens in a conical shape with one end side in the vertical direction being the lower side in the vertical direction. A collecting member to collect;
A passage hole through which the fish egg passes is formed at one end, and is attached to the collection member so as to communicate with the opening formed at the other end of the collection member, and is captured by the collection member. A storage container for storing collected fish eggs;
A fish egg collector, comprising: a floating member attached to a storage container and having buoyancy with respect to water. The fish egg collector according to claim 1 , wherein the mesh opening is 400 μm or more and 1000 μm or less . The fish egg collector according to claim 1 or 2 , wherein the container is made of a transparent material .

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