JP2006101738A - Water tank for ashore cultivating migratory fish - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water tank for culturing migratory fish, making it possible that the migratory fish, such as tuna fish, move safely and enough, without colliding against a wall surface, and adult fish and young fish thereof coexist therein, and further the tank itself does not pollute the sea, nor is suffered from pollution by the sea. <P>SOLUTION: This water tank for ashore culturing the migratory fish comprises a large-sized circular land water tank (1), wherein migration lanes (30, 20, 10) for exclusive use of each group of the young fish, fry young fish, and the adult fish are concentrically arranged outside a drainage circular part (40) which is arranged in the center of the water tank, the migration lanes are separated from one another by net sheets (2, 2) equipped with opening and closing doors (3, 3,...), so that only water passes through the net sheets, and water flow generators (4, 4,...) for generating circulating water flows in an identical direction along each of the lanes are arranged in the lanes. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an aquaculture tank intended to cultivate migratory fish such as tuna on land.

   The tuna species preferred by the Japanese have been supplied from the sea around the world to the Japanese table as a target for pelagic fishing. In recent years, however, the catch has gradually increased, and it has been designated as an endangered species and its catch has been restricted. In the future, it is not unpredictable that whales might be banned.

  Therefore, artificial farming of tuna has been tried, but the method is to use a round or oval net cage with a diameter of about 30 m and a depth of about 10 m on the sea surface. The one immediately after hatching is called fry, and the top is called juvenile and adult fish.) However, there are many difficulties with this method, and operators are constantly struggling.

The main ones of the difficulties are as follows.
(1) The ocean is contaminated with food leftovers and feces.
(2) Since the fish are raised on a narrow sea surface, the fish is stressed due to lack of exercise, resulting in a fat-rich and easily oxidized meat that degrades quality and taste.
(3) When a fish is surprised, it crashes into the net at a tremendous speed, and it is easy to get injured or dead.
(4) Since shellfish and seaweed adhere to the net cage, the burden and cost of removing it and replacing it are large.
(5) Red tide damage that occurs frequently in summer, environmental effects of antibiotics used to combat diseases, problems of accumulation in fish, and broken nets caused by typhoon damage.
(6) Since the tuna that has reached the shipping size cannibalizes the fry, you can't put in the new fry unless you take out all the tuna and send it out. Therefore, a cycle of replenishing fry while shipping according to demand in one aquarium cannot be realized.

  Various attempts have been made to solve these problems, and many patents have been filed. Among them, there are the following patent documents 1 or 2, but a direct relevance with the present invention is not recognized.

JP 2002-233268 A Japanese Patent Laid-Open No. 2003-265065

  In order to solve many of the above-mentioned problems, the present invention allows migratory fish such as tuna to move safely and sufficiently without colliding with the wall surface, that adult fish and juvenile fish, fry can coexist, and does not pollute the sea. The goal is to avoid pollution from the sea.

The above problem can be solved by the following aquaculture tank.
In other words, it is a large onshore circular aquarium, and the lanes for fry, larvae, and adults are arranged concentrically outside the drainage cylinder located in the center, and each lane is opened and closed. It is characterized in that a water flow generator is provided that isolates water by a net sheet with a door so that only water can communicate, and generates a circulating water flow in the same direction along each lane.

  The above-mentioned problem that “the migratory fish can move safely and sufficiently without colliding with the wall surface” is solved by generating a water flow circulating at a predetermined speed along the water channel in the aquaculture tank. The migratory fish swims against the water current and makes it possible to swim as much as possible to get the necessary momentum and relieve stress. The relative speed between the fish and the surrounding walls and nets can be reduced, reducing the number of accidents in which migratory fish crash into the net. In addition, it is said that if stress is not applied, the stress substance will not accumulate in the fish body and the taste will be improved.

  In addition, the above-mentioned problem that “adult fish, juvenile fish, and fry can coexist” can be solved by dividing one aquaculture tank into a plurality of regions according to the stage of fish growth. Moreover, by forming each region as a concentric circular lane, it can also serve as a means for solving the above-mentioned problem that “the migratory fish can move safely and sufficiently”. In addition, since it is the same as having one dedicated aquarium for each stage of fish growth, it is possible to ship fish year round while growing the fish one after another.

  1st Embodiment of this invention is related with the net sheet which isolates between said migratory lanes. This net sheet is composed of a net and a sheet, and the net has a mesh size that fish cannot pass through, and is arranged separately on the upper and lower parts of the net sheet, avoiding intermediate water depth where fish density is high. In addition, the seat has strength and elasticity that cannot be broken even when a migratory fish collides at full speed, and is provided with doors at several places.

  If the opening / closing door provided on the net sheet is used, it can be easily moved between the lanes while preventing the fish from being damaged. When the adult fish that has grown to the shipping size is taken out from the migration lane, the door is opened to move the young fish to the trace, and the young fish is put in the trace of the young fish. This prevents cannibalism and at the same time improves the utilization efficiency of the aquaculture tank.

  The second embodiment of the present invention is to install the aquaculture tank according to the present invention on land as its name suggests. By doing so, the aquaculture tank is not separated from the marine environment and does not pollute the sea, and conversely, it is not subject to pollution from the sea such as adhesion of shellfish and seaweed and red tide.

  In order not to pollute the sea, wastewater from this aquaculture tank is treated, and environmental pollutants such as uneaten food and feces are removed with a filter. The removed organic matter is processed with a garbage processing machine and used effectively. Part of the wastewater after the filter treatment is discharged to the outside, and fresh makeup water is added to the remaining water and returned to the water tank while appropriately performing ozone sterilization. At that time, barnacles, oyster eggs, organic substances, etc. are removed with a filter of about 50 microns in order to block contamination derived from makeup water.

  FIG.1 and FIG.2 is the top view and elevation which show the aquaculture tank for migratory fish as one Example of this invention. In the figure, reference numeral 1 is a water tank body partition, 2 is a net sheet for partitioning each excursion lane, 3 is an opening / closing door provided on the net sheet, 4 is a water flow generator for generating a circulating water flow along each excursion lane, 5 is a drainage pipe provided in the cylindrical part 40 at the center of the aquarium, 10, 20, 30 are migration lanes dedicated to adult fish, juvenile fish, and juvenile fish in this order.

  The diameter of the aquaculture circular water tank of this example is 30 m, and the height is about 11 m. Such a large aquarium is usually made of concrete or steel plate, but the one of this embodiment is made of concrete. Then, as shown in FIG. 1, the lanes 10, 20, 30 are dedicated to adult fish, juvenile fish, and juvenile fish in order from the outside. Each migratory lane is provided with water flow generators 4 and 4 to generate a circulating water flow at a predetermined flow rate for each lane.

  The three circuit lanes 10, 20, and 30 are partitioned by cylindrical net sheets 2 and 2. As shown in FIG. 2, the structure of the net sheet 2 is such that the upper part of about 2 m height and the lower part of about 1 m form a net, and the intermediate part sandwiched between the nets is a sheet. . A net is provided to ensure the water flow between the lanes, and a sheet is provided to separate the lanes and prevent large and small fish from entering.

  In the illustrated example, the width of each lane is 5 m, 5 m, and 2.5 m in order from the outside, but can be appropriately changed according to the size and quantity of fish. The central part 40 is a cylinder with a diameter of 5 m for drainage. An arched window is provided between the lower end of the cylinder 40 and the bottom of the water tank, and a net of about 5 cm square is attached so that fish cannot pass. The drain pipe 5 opens in the cylinder 40.

  The tip of the drainage pipe 5 is connected to a wastewater treatment apparatus, but the illustration and description of the wastewater treatment apparatus are omitted.

  Since the present invention relates to an aquaculture tank for migratory fish, it is expected to be useful in a wide range of industries such as the fishery industry, marine product processing industry, transport industry, and civil engineering construction industry.

It is a top view of the aquaculture tank of migratory fish as one Example of this invention. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Concrete wall 2 Net sheet 3 Opening and shutting door 4 Water flow generator 5 Drain pipe 10 Adult fish excursion lane 20 Juvenile excursion lane 30 Juvenile excursion lane 40 Drain cylindrical part

Claims (3)

  A large land circular aquarium (1) with concentric circular lanes (30, 20, 10) dedicated to fry, larvae and adults on the outside of the central drainage cylinder (40). The water flow is generated between the circuit lanes so that only the water can communicate with the net sheet (2, 2) with open / close doors (3, 3,...). An aquaculture tank for migratory fish, characterized by providing a vessel (4, 4, ...).   The net sheet (2) is composed of a net and a sheet, the net has a mesh size that does not allow fish to pass through, and is arranged separately at the top and bottom of the net sheet, and the sheet is not broken even if the fish collides at full speed. The aquaculture tank according to claim 1, which has strength and has doors (3, 3, ...) at several places. A constant amount of water in the aquarium is always discharged, and after removing environmental pollutants in the wastewater by a predetermined water treatment method, a certain proportion is discharged to the outside, and the remainder is returned to the aquarium with fresh makeup water. The aquaculture tank according to claim 1.

Images