JP2014036624A - Growth bank for sea cucumber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a growth bank for sea cucumbers which allows sea cucumber larvae freely swimming under the sea to easily settle and allows young sea cucumbers developed from the larvae to safely inhabit, and which has excellent durability and strength and is easily maintained.SOLUTION: A bottomed cylindrical growth bank 10 for acquiring and growing sea cucumber larvae freely swimming under the sea includes: a lower structure 14 of which inner space is filled with stones S; an upper structure 11 which has a framed structure including posts 12 and beams 13 and is placed on the lower structure 14; gratings 17, 18, and 19 which respectively covers openings 20, 21, and 22 provided in peripheral walls 15 of the lower structure 14 and in the side surfaces and top surface of the upper structure 11. The gratings 18 mounted in the side surfaces of the upper structure 11 serve as larva acquisition parts for acquiring sea cucumber larvae freely swimming under the sea, and the lower structure 14 of which inner space is filled with stones S serves as a young sea cucumber growing part for growing young sea cucumbers developed from the larvae.

Description

  The present invention relates to a sea cucumber propagation reef that captures and nurtures sea cucumber larvae floating in the sea.

  In recent years, in China, the wealthy class has increased due to rapid economic development, and the demand for dried sea cucumber, a high-quality food, has expanded. Along with this, sea cucumber products exported from Japan to China are rapidly increasing. However, if sea cucumbers are overfished, sea cucumber resources will be depleted and stable supply of sea cucumbers will not be possible. Therefore, breeding and aquaculture are carried out as measures to recover sea cucumber resources.

  Proliferation refers to means and techniques for recovering fishery resources in natural waters or recovering them more actively or increasing and maintaining natural resources (see Non-Patent Document 1). Seedlings and natural seedlings are practiced.

In sea cucumber artificial seedlings, eggs and sperm collected from the parent sea cucumber are mixed and fertilized, and hatched larvae are collected and larva reared, and when grown into juvenile sea cucumbers, intermediate breeding is performed. The juvenile sea cucumber that has grown to a length of about 15 to 20 mm is submerged in a reef zone and a boulder zone that are shallower than 10 m.
In the case of egg laying of manamako, spawning induction by temperature stimulation is generally performed, but the induction rate is not necessarily high, and manamako does not know the sex and maturity from the appearance, so prepare many individuals for spawning induction There is a need. Therefore, Patent Document 1 discloses an invention of a sea cucumber ovulation / fertilization inducer and a sea cucumber production method using the same. According to Patent Document 1, it is possible to surely cause egg laying and fertilization at any time using sea cucumbers in the spawning period, so that planned and efficient production of fertilized eggs at the seedling production site Is going to be possible.

  In the case of natural sea cucumber seedlings, a method has been conventionally used in which shellfish such as oysters or stones are placed in a cage and suspended in the sea so that sea cucumber larvae grow between the shells and stones. Recently, a method has been tried to multiply sea cucumbers by placing the bamboo shoots with their branches upside down on a tidal flat and placing building blocks around them. According to this method, eddy currents are generated in the bamboo branches and the larvae of the sea cucumber are easily formed, and the outflow of the sea cucumber that has grown can be prevented by the wave-dissipating effect.

  On the other hand, aquaculture occupies a certain area, manages the life and environment of self-owned seafood and algae, etc. in that area, aims to breed and grow these organisms, and is the target size (product size) (See Non-Patent Document 1). For example, in patent document 2, a baffle is arrange | positioned above the lattice frame for the sea cucumber storage arrange | positioned at the bottom part of a culture tank main body, and a side net | network is stretched by the water flow window provided in the side wall of the culture tank main body. At the same time, a sea cucumber aquaculture facility is disclosed in which a top net is stretched over the top opening of the main body of the aquaculture tank.

JP 2010-53041 A Japanese Utility Model Publication No. 64-43666

Toshio Takeuchi et al., “Fisheries Marine Handbook”, Biological Research Institute, 2004

However, recovery of sea cucumber resources by the conventional method described above has the following problems.
In other words, sea cucumber artificial seedlings have a problem that the survival rate during initial breeding is low and the variation in growth among individuals is large.
In addition, in the case of conventional natural seedlings, it is because there are few green algae as feed in the gaps in the shells, etc., in addition to the juvenile sea cucumber not becoming too large, the juvenile sea cucumber that has entered the gap does not go out easily There's a problem. Furthermore, in the case of natural seedling using bamboo shoots and shiba, there is a problem that bamboo and shiba must be replaced every year.

  On the other hand, in the case of the sea cucumber aquaculture facility described in Patent Document 2, the sea cucumber aquaculture facility is fixed on a carriage that moves on a pair of rails laid from the land to the seafloor aquaculture site. The trolley must be lifted from the farm to the land. For this reason, in addition to the power cost for lifting the carriage from the farming site to the land, there is a problem that the equipment cost for laying the rails is enormous.

  Because sea cucumber females produce hundreds of thousands to millions of larvae in a single egg laying, many larvae should float around the fishing grounds, but most of them are invalid and cannot become larvae. Distributed and dead. The present invention has been made in view of such circumstances, and the larvae of sea cucumbers floating in the sea are easy to settle, become a safe habitat for juvenile sea cucumbers grown from the larvae, and have excellent durability and strength. The purpose is to provide a sea cucumber breeding reef that is easy to maintain.

To achieve the above object, the present invention is a sea cucumber breeding reef that captures and nurtures sea cucumber larvae floating in the sea,
A lower structure consisting of a bottomed cylindrical body with stones stacked in the internal space;
An upper structure composed of a frame structure composed of columns and beams, and disposed on the lower structure;
A grating covering each of the peripheral wall of the lower structure and the openings provided on the side surface and the top surface of the upper structure;
The grating attached to the side surface of the upper structure is a larvae catcher that catches sea cucumber larvae floating in the sea, and the lower structure on which the stones are stacked is changed from larvae to juvenile sea cucumbers. It is characterized by being a juvenile sea cucumber breeding department that nurtures the sea cucumber that has grown.

  In this specification, sea cucumbers from 2 to 3 weeks after hatching are referred to as “sea cucumber larvae”, and sea cucumbers that have grown from larvae to a length of about 1 mm to 20 mm are referred to as “young sea cucumbers”. A sea cucumber with a body length of around 30 mm may be called a “young sea cucumber”.

  The sea cucumber breeding reef according to the present invention is installed in a shallow area, and catches sea cucumber larvae floating in the sea with a grating attached to the side of the upper structure. Sea cucumber larvae that settled on the grating grid grow into juvenile sea cucumbers. The sea cucumber that became a juvenile sea cucumber moved to the internal space of the lower structure on which stones were stacked, and further grew in the gap between the stones to become a juvenile sea cucumber, which was provided on the peripheral wall of the lower structure Move from the opening to an offshore fishing ground.

  In the sea cucumber breeding reef according to the present invention, it is preferable that the opening width of the meshes constituting the grating is 20 mm or more and 100 mm or less, and the depth length of the meshes is 25 mm or more and 100 mm or less. .

If the opening width (inner width) of the grating mesh is less than 20 mm, there is a risk of clogging due to algae and detritus (fine organic particles such as biological discharges and carcasses) attached to the grating. If it is super, the opening is too large, making it difficult for the sea cucumber larvae to settle and for easy entry of foreign enemies.
On the other hand, when the depth of the grating is less than 25 mm, the growing space is too narrow and it is difficult for the sea cucumber larvae to settle. When it exceeds 100 mm, it takes time to manufacture and attach the grating.

  In the sea cucumber breeding reef according to the present invention, the grating may be made of FRP. By making the grating made of FRP, it is possible to obtain a grating that is lightweight and has excellent durability and strength.

  The sea cucumber breeding reef according to the present invention comprises a larvae catching part composed of a grating that is easy for the larvae of sea cucumbers floating in the sea, and a juvenile sea cucumber breeding part that serves as a safe habitat for juvenile sea cucumbers grown from the larvae. Therefore, sea cucumber resources can be recovered more efficiently than before. In addition, the sea cucumber breeding reef includes a lower structure made of a bottomed cylindrical body and an upper structure made of a frame structure, so that excellent durability and strength are ensured, and maintenance is easy.

It is a perspective view of the sea cucumber breeding reef which concerns on one embodiment of this invention. It is a disassembled perspective view of the sea cucumber breeding reef. It is a partial expansion perspective view of grating.

  Next, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention.

  The sea cucumber breeding reef 10 according to one embodiment of the present invention includes an upper structure 11 having a larva catching part for catching larvae of sea cucumbers floating in the sea, and a juvenile that nurtures sea cucumbers that have grown from larvae to juvenile sea cucumbers. It is roughly comprised from the lower structure 14 used as a sea cucumber rearing part (refer FIG.1 and FIG.2). The lower end portion of the upper structure 11 and the upper end portion of the lower structure 14 are joined, and the upper structure 11 and the lower structure 14 are submerged in the sea as an integrated object.

  The upper structure 11 is composed of a reinforced concrete frame structure formed in a hexagonal column shape with columns 12 and beams 13. Openings 21 and 22 provided on each side surface and top surface of the upper structure 11 are gratings 18 and 19. Covered. The grating 18 attached to each side surface of the upper structure 11 serves as a larva capturing part that captures sea cucumber larvae floating in the sea. In addition, the grating 19 attached to the top surface of the upper structure 11 functions as a light shielding unit that prevents direct sunlight from entering the sea cucumber breeding reef 10 by algae growing.

The lower structure 14 is composed of a reinforced concrete bottomed cylindrical body composed of a regular hexagonal flat bottom 16 and a peripheral wall 15 formed on the peripheral edge thereof in plan view. A plurality of stones S having a large size are stacked. Further, an opening 20 is formed on each side surface of the peripheral wall 15 having a hexagonal column shape, and each opening 20 is covered with a grating 17. The juvenile sea cucumber grows into a juvenile sea cucumber in the internal space of the lower structure 14 and moves to the fishing ground via the grating 17 attached to the opening 20 provided in the peripheral wall 15.
In addition, the stone S piled up in the internal space of the lower structure 14 should just be the stone which exists in the area which installs the sea cucumber breeding reef 10, and does not specifically limit a material, a shape, etc.

  The gratings 17, 18, and 19 are made of FRP (fiber reinforced plastic), and have a frame in which a plurality of strip plates 26 and 27 are combined in a lattice shape (see FIG. 3). The opening width (internal width) W of the grids 25 of the gratings 17, 18, and 19 is 20 mm or more and 100 mm or less, and the depth length H of the grids 25 is 25 mm or more and 100 mm or less. In addition, the board thickness of the strip | belt board materials 26 and 27 is 3 mm or more and 10 mm or less.

  Because sea cucumbers lay eggs in shallow water, many sea cucumber larvae are floating in the shallow water. It is thought that juvenile sea cucumbers that grew from larvae to juvenile sea cucumbers lived in shallow reefs and boulders, and when they grew into juvenile sea cucumbers, they would gradually move to fishing grounds during low water temperatures. Therefore, in order to move the juvenile sea cucumber to the fishing ground efficiently, it is necessary to create an environment in which the sea cucumber larvae settle (set) and grow from the juvenile sea cucumber to the juvenile sea cucumber. Manamako is said to sleep during the high water temperature when it is over one year old, and it is necessary to prepare a place to become a retreat during summer sleep.

  The sea cucumber breeding reef 10 has a configuration based on the life history of the sea cucumber. That is, the grating 18 attached to the side surface of the upper structure 11 serves as a larva catching part for catching sea cucumber larvae floating in the sea, and the lower structure 14 in which stones S are stacked in the internal space It becomes the juvenile sea cucumber upbringing department to nurture sea cucumbers that have grown into juvenile sea cucumbers. In addition, the lower structure 14 also has a function of a hideout where the juvenile sea cucumber sleeps.

When the sea cucumber breeding reef 10 is installed on the seabed, it is installed in a shallow place with a depth of about 5 m. As a result, a large number of sea cucumber larvae floating in the sea grow on the grid 25 of the grating 18 attached to the side surface of the upper structure 11. In addition, algae and detritus that feed on sea cucumbers grow on the grids 25 of the gratings 18 and 19 attached to the side surface and the top surface of the upper structure 11.
The sea cucumber larva grows in the lattice 25 of the grating 18 to become a juvenile sea cucumber and moves to the internal space of the lower structure 14 on which stones S are stacked. The juvenile sea cucumber grows further in the gap between the stone S and becomes a juvenile sea cucumber, and moves from the opening 20 provided in the peripheral wall 15 of the lower structure 14 to the offshore fishing ground.

  Although one embodiment of the present invention has been described above, the present invention is not limited to the configuration described in the above-described embodiment, and is within the scope of matters described in the claims. Other possible embodiments and modifications are also included. For example, in the above-described embodiment, the planar shape of the sea cucumber breeding reef is a hexagon, but it goes without saying that it may be another polygon such as a quadrangle or a pentagon. Further, in the above-described embodiment, the grid of the grating is a lattice shape, but other shapes such as a honeycomb shape may be used.

10: Sea cucumber breeding reef, 11: Upper structure, 12: Pillar, 13: Beam, 14: Lower structure, 15: Perimeter wall, 16: Flat bottom, 17, 18, 19: Grating, 20, 21, 22: Opening, 25: Grid, 26, 27: Strip material, S: Stone, W: Opening width, H: Depth length

Claims (3)

A sea cucumber breeding reef that captures and nurtures sea cucumber larvae floating in the sea,
A lower structure consisting of a bottomed cylindrical body with stones stacked in the internal space;
An upper structure composed of a frame structure composed of columns and beams, and disposed on the lower structure;
A grating covering each of the peripheral wall of the lower structure and the openings provided on the side surface and the top surface of the upper structure;
The grating attached to the side surface of the upper structure is a larvae catcher that catches sea cucumber larvae floating in the sea, and the lower structure on which the stones are stacked is changed from larvae to juvenile sea cucumbers. A sea cucumber breeding reef characterized by being a juvenile sea cucumber breeding section for breeding the grown sea cucumber.   The sea cucumber breeding reef according to claim 1, wherein the opening width of the meshes constituting the grating is 20 mm or more and 100 mm or less, and the depth length of the meshes is 25 mm or more and 100 mm or less. Breeding reef.   The sea cucumber reef according to claim 1 or 2, wherein the grating is made of FRP.

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