JP2005073600A - Method and apparatus for nursing egg/larva of coral by direct trap - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a nursing method which uses a direct trap, and by which eggs and/or larvas of a coral to be easily damaged are precisely collected without being damaged, and nursed in a stable environment; and to provide a nursing apparatus. <P>SOLUTION: The nursing method using the direct trap comprises arranging the trapping and nursing apparatus at the upper part of the target coral which is the object for the collection of the eggs and/or the larvas, hanging a region-partitioning member to an upper part near to the target coral on the sea bottom so as to form an opened state at the bottom part, collecting the eggs and/or the larvas laid and floating in a collection region when collecting the eggs and/or larvas of the coral, and nursing the eggs and/or the larvas collected in a nursing region formed by closing the lower part of the region-partitioning member when nursing the eggs and/or the larvas of the coral. The trapping and nursing apparatus has the region-partitioning member 2 for partitioning the collection region for collecting the eggs and/or the larvas of the coral by being attached to a buoyancy-imparting body 1 so as to form the opened state at the bottom part, and partitioning the nursing region for nursing the eggs and/or the larvas of the coral by forming a closed state at the bottom part, and a water-permeable water-changing net holes 5 at least installed in a part for partitioning the nursing region of the region-partitioning member, and preventing the eggs and/or the larvas of the coral from flowing out to the exterior from the nursing region. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention collects coral fertilized eggs and / or planula larvae (hereinafter abbreviated as “eggs / larvae”) that grow little in nature and never settle, and cultivate them to coral. The present invention relates to a childcare method and a childcare device using a direct trap of coral eggs and larvae for promoting the growth and bottoming of rice.

In recent years in Okinawa and other parts of the world due to the disappearance of shallow water due to land reclamation, the decrease in seawater transparency caused by land development such as farmland development and road maintenance, the rise in seawater temperature due to global warming, etc. The decline of coral reefs, such as coral community whitening, death and death, is a serious problem.

  However, many of the reef-building corals including corals of the genus Midori, etc., release a large amount of eggs and sperm every year by simultaneous egg laying, fertilized near the sea surface to become fertilized eggs, and transformed into planula larvae, These larvae drift on the surface of the sea, eventually settle down where they should settle, transform to form polyps, and further grow into coral colonies by asexual reproduction. And in the natural world, the probability that the larva settles and transforms to form a polyp, in addition to the severe initial consumption, the environmental conditions for landing and transformation are severe, and it remains at a very low value. It is difficult to stop the decline of coral reefs by nature.

  Therefore, attempts have been made to artificially restore the coral reef. For example, the surface of the coral bottom base such as a wave-dissipating block is subjected to processing such as unevenness to promote the coral bottom. , A method for improving the foundation comprising fixing a base material for accelerating deposition to a bedrock or a breakwater (Japanese Patent Laid-Open No. 2003-61,506), a transplant obtained by cutting or dividing a part of a healthy coral Is fixed at a predetermined position on the seabed by means such as a stinging projection or a transplantation assisting tool, or is transplanted by growing and growing without fixing (Japanese Patent Laid-Open Nos. 6-303,875, 7-39,270, Kaihei 8-112,048, JP-A-9-121,712, JP-A 2001-238,563, JP-A 2001-321,001, JP-A 2002-45,075) Cut out as it is and temporarily evacuate during construction, or move / remove method to move, Eggs and larvae are collected from slicks produced by simultaneous coral spawning in coral reef sea areas, cultured indoors, and then settled on a ground base such as concrete pieces, tiles, stones, etc. -276,013, Japanese Laid-Open Patent Publication No. 2002-272,307), or floating culture ponds for cultivating collected eggs and larvae in the sea area where corals are settled and attach to the seabed The bottom base is surrounded by a net to form a field, and the coral larvae cultured in the floating culture pond are sent from the bottom of the floating culture pond to the inside of the field net with a supply hose to be settled (Mar Ecol Prog Ser 230; 113- 118, 2002), etc., and seedling production methods using eggs and larvae have been tried.

  However, the base improvement method is not effective in the sea area where there is no supply of planula larvae, and the transplanting method requires a lot of labor for cutting out the graft in the sea, and also causes a lot of damage to the natural coral itself. In addition, there is a problem that damage is caused to the coral reefs, and the evacuation / relocation method requires heavy work such as heavy machinery, resulting in high cost, and the evacuation / relocation destination is suitable for coral growth. As a result, it may not be effective if there is no sea area.

  Therefore, at present, the seed and seedling production method is the place where the most is expected, but after the egg laying, the bundle's thin skin that has risen to the vicinity of the sea surface is broken and fertilized 1 to 2 hours later, and then cleavage begins in 2 to 3 hours, Furthermore, it becomes an embryo in 12 to 18 hours, and then transforms into a larva in 24 to 36 hours. During this period, it is easy to ache from the cleavage stage after fertilization, and when it is nighttime, eggs and larvae are collected. In practice, eggs and larvae must be collected the next morning. However, when eggs and larvae are collected the next morning after laying eggs, slicks may not be formed due to strong winds, etc., making it impossible to collect eggs and larvae, and eggs and larvae are trapped in breakwaters such as fishing ports. In many cases, eggs and larvae collected at such locations include individuals that have died by colliding with breakwaters. In such cases, the eggs and larvae are eluted from dead individuals. Healthy fertilized eggs and planula larvae are trapped and weakened by sticky substances, leading to death, and generally the survival rate of eggs and larvae collected in breakwaters such as fishing ports is greatly increased. To drop.

  As for the method of collecting coral eggs, a funnel-shaped main body installed on the seabed so as to cover the coral, and a collection container detachably connected to the upper end on the small diameter side of the main body. There has been proposed a coral egg collection device configured to collect coral eggs immediately after spawning collected in a collection container through a main body after egg laying from the seabed (Japanese Patent Laid-Open No. 2002-272,307). However, this collection device is suitable for collecting eggs from corals of a specific variety, but in order to collect and collect them in a relatively small collection container, it is necessary to collect them from the seabed during the night immediately after laying eggs. It is not suitable for collecting large quantities of eggs and larvae from relatively large coral colonies.

JP-A-6-303,875 Japanese Patent Laid-Open No. 7-39,270 JP-A-8-112,048 JP-A-9-121,712 Japanese Patent Laid-Open No. 11-276,013 JP 2001-238,563 A JP 2001-321,001 Japanese Patent Laid-Open No. 2002-272,307 Japanese Patent Laid-Open No. 2002-45,075 JP2003-61,506 Mar Ecol Prog Ser 230; 113-118, 2002

  Therefore, the present inventors have intensively studied means that can be reliably collected without damaging coral eggs and larvae that are spawned all at once, and that can be nurtured in a stable environment. As a result, when coral eggs and larvae are collected, the buoyancy-giving body is suspended from the buoyancy imparting body to the upper part near the target coral on the seabed, and a collection area for collecting coral eggs and larvae that are spawned and floated is defined. The present invention has been completed by finding that the object can be achieved by using a region partition member that blocks the bottom of the coral eggs and larvae that have been collected, and that divides the nursery region in which the collected coral eggs and larvae are to be raised.

  Accordingly, the object of the present invention is to provide coral eggs and larvae that can be reliably collected without damaging coral eggs and larvae that are spawned all at once and are easily damaged, and that can be raised in a stable environment. It is to provide a trap childcare device.

  Another object of the present invention is to provide coral eggs that can be laid in one go and can be reliably collected without damaging easily damaged coral eggs and larvae, and can be raised in a stable environment. -To provide a method for raising larvae traps.

  That is, the present invention is a buoyancy imparting body that floats above the target coral that is the target of egg / larvae collection, and is attached to the buoyancy imparter, at the time of coral egg / larvae collection. The bottom of the coral is suspended from the buoyancy imparting body to the upper part near the target coral on the seabed, and divides the collection area for collecting eggs and larvae that are spawned and floated. An area partition member for partitioning a nursery area for raising the coral eggs and larvae that are blocked and collected, and a passage member provided on the area partition member to prevent at least the coral eggs and larvae from flowing out of the nursery area. It is a coral egg / larvae trap nursery device equipped with a water exchangeable net hole.

  The present invention also relates to a coral egg / larvae that is attached to the buoyancy imparting body and is attached to the buoyancy imparting body above the target coral that is a target for collecting eggs and larvae. An area division member that divides a collection area for collecting coral eggs and larvae in a state where the bottom portion is closed, and a coral egg / larvae provided at least from the childcare area provided in the area division member A trap nursery device equipped with a water exchangeable net hole that prevents water from flowing outside is arranged, and when collecting coral eggs and larvae, the above-mentioned area partitioning member is suspended to the upper part near the target coral on the seabed with the bottom open. Coral eggs and larvae that have been spawned and floated in the collection area are collected, and when coral eggs and larvae are nurtured, they are collected in a nursery section that is formed by closing the lower part of the area partition member. To childcare the eggs, larvae of coral, is a trap nursery method of coral egg-larvae.

  In the present invention, the buoyancy imparting body that constitutes the trap childcare device partitions the collection area when coral eggs and larvae are collected, and the area partition member that partitions the childcare area when coral eggs and larvae are raised. However, it may be anything that can float above the target coral that is the target of egg / larvae collection, and examples include ginger ridges, oil fences, silt fences, and the like.

  In addition, when the coral eggs and larvae are collected, the region partition member divides a collection region for collecting coral eggs and larvae that hang from the buoyancy imparting body to the upper vicinity of the target coral on the seabed in an open state, and are spawned and floated. In addition, when the coral eggs and larvae are collected, the bottom is blocked, and the childcare area where the collected coral eggs and larvae are raised is defined, and the collection area and childcare area can be reliably defined. Also, it is only necessary to prevent the coral eggs and larvae collected and nurtured from leaking to the outside, and there are no particular restrictions on the material, shape, size, etc.

  Examples of the material of the area partition member include sheet materials and plate materials such as polyvinyl chloride sheets (polyvinyl chloride sheets) and polyethylene sheets. Coral eggs and larvae are divided into childcare areas at the time of childcare. Since there is a tendency to gather near the water line of the area partition member to be attached and to die, it is preferable to select a material to which the coral eggs and larvae are difficult to adhere as much as possible.

  As for the shape of the area partitioning member, for example, an upper cylindrical part that divides the periphery of the nursery area at the top and a lower peripheral edge of the upper cylindrical part, and at least a bottom part when coral eggs and larvae are collected. In the open state, it hangs down to the upper part near the target coral on the seabed, and divides the collection area, and when coral eggs and larvae are raised, it has a lower hanging part that blocks the bottom of the upper cylindrical part and divides the raising area The upper cylindrical portion may be circular, rectangular, or polygonal, and the size of the area partition member may be the trap childcare device. Can be designed as appropriate according to the size of the coral and its environment, as well as the size and density of the target coral from which eggs and larvae are collected. About 0. ～2.0M, it's better and preferably about 0.5～1.0M.

  Further, the lower hanging portion of the region partitioning member may be formed of a single member or may be divided into a plurality of members, or simply suspended in a goodwill shape. The hanging length may be adjusted in a bellows shape or a slide shape according to the hanging length to the target coral, and further, the lower portion in consideration of the size of the target coral. May be expanded and drooped downward. And, for the interval between the lower end of the lower drooping part and the target coral that is the target of egg / larvae collection below it, in order to efficiently collect eggs / larvae that are spawned from the target coral and rise Usually, it is good to make it 2 m or less, preferably 1 m or less.

  The region partition member is provided at least in a portion that partitions the nursery region of the region partition member, and a water exchangeable water net hole that prevents coral eggs and larvae from flowing out of the nursery region. During the nursery period until the collected coral eggs and larvae are supplied to the bottom of the sea area and settled, the water is exchanged between the sea water inside the nursery area and fresh fresh sea water. The environment suitable for childcare can be formed. The size of the water exchange net hole should be 0.25 mm or less to prevent the coral eggs and larvae from distilling outside, and the water flow of seawater should be as smooth as possible. It should be 0.2 mm or more.

  In the trap childcare device of the present invention, preferably, the buoyancy imparting body is provided with a watering device for pumping fresh seawater from the outside of the childcare region and sprinkling water near the upper part of the waterline in the childcare region of the region partition member. During the egg and larval nursery period, water should be sprayed near the upper part of the waterline in the nursery area, so that not only can fresh water be supplied from outside the nursery area to the inside of the nursery area, but also within the nursery area. Eggs and larvae that tend to gather near the waterline can be reliably prevented from adhering to the upper part of the waterline in the nursery area and dying on the spot because they cannot return to seawater and dry.

  The watering device is not particularly limited as long as it can spray water near the upper part of the water line in the nursery area of the area partition member. For example, the submersible pump or the pump for pumping seawater and the area partition member It is arranged at the upper part of the waterline in the childcare area, and is connected to the above-mentioned submersible pump or pump, and is constituted by a watering hose having a number of nozzle holes provided at predetermined intervals. it can.

The trap childcare device of the present invention is moored at the time of coral egg / larvae collection above the target coral in the coral habitat and above the target coral targeted for egg / larvae collection. With the bottom open, it hangs down near the target coral on the seabed, and if necessary, its lower end is fixed to the seabed, and a collection area for collecting coral eggs and larvae is defined to wait for coral spawning.
Eggs and larvae of spawned corals are collected floating in this collection area.

  Usually, the day after egg laying, the lower part of the area partition member is closed to partition the coral nursery area, and eggs and larvae are raised while watering near the upper part of the waterline in the nursery area, preferably with a watering device. . The coral eggs and larvae may be maintained at the site where the coral eggs and larvae are collected, or towed to a safe place if necessary, such as during strong winds. Furthermore, it may be carried out by towing to a field where the grown planula larvae are settled.

  According to the present invention, when coral eggs and larvae are collected, a buoyancy imparting body is suspended from the bottom of the bottom to the upper vicinity of the target coral on the seabed, and a collection area for collecting coral eggs and larvae that are spawned and floated is defined. In addition, the bottom of the coral eggs and larvae that have been collected is clogged, and by using an area partitioning member that divides the nursery area in which the collected coral eggs and larvae are nurtured, the coral is easily spawned and easily damaged. It can be reliably collected without damaging eggs and larvae, and can be raised in a stable environment.

  Hereinafter, preferred embodiments of the present invention will be specifically described based on examples shown in the accompanying drawings.

[Example 1]
1 to 3 show a coral egg / larvae trap nursery apparatus A according to Embodiment 1 of the present invention.
The trap childcare apparatus A includes a buoyancy imparting body 1 formed by a square frame 1a and a total of eight floats 1b attached to each side of the frame 1a, and an upper end of the frame 1a. The upper cylindrical part 3 is attached to the upper part, and the lower part of the upper cylindrical part 3 has four rectangular lower hanging parts 4 suspended from the lower edge of each of its four sides. And an area partition member 2 made of a vinyl chloride sheet, and four water exchangeable net holes 5 that are provided on four side wall surfaces constituting the upper cylindrical portion 3 of the area partition member 2. ing.

  In the first embodiment, the four lower hanging parts 4 are provided with resin fasteners that can be used in water at the respective ridges, so that when coral eggs and larvae are collected, Open the zipper at the top, hang the bottom drooping part 4 to form a collection area for collecting eggs and larvae that are spawned and float, and close the zipper when closing coral eggs and larvae With 4 as the bottom, a childcare area is formed to raise the collected coral eggs and larvae.

  In the first embodiment, the frame 1a of the buoyancy imparting body 1 includes a submersible pump 6a that pumps seawater from the outside of the apparatus, and a water line in the upper cylindrical portion 3 of the region partition member 2 that forms a childcare region when in use. There is provided a watering device 6 which is arranged at the upper part and is connected to the submersible pump 6a and which is composed of a watering hose 6b having a number of nozzle holes provided at predetermined intervals. -Eggs and larvae that sprinkle fresh seawater near the upper part of the waterline in the childcare area formed by the upper cylindrical part 3 of the region partition member 2 during larval childcare and tend to gather and adhere near the waterline in the childcare area. While preventing adhesion, fresh seawater can be supplied to the inside of the childcare area from the outside of the trap childcare device A.

  1 to 3, reference numeral 7 denotes a weight attached to each lower hanging portion 4 of the region partition member 2, and when coral eggs and larvae shown in FIG. 2 are collected and coral eggs and larvae shown in FIG. It serves to ensure that the upper cylindrical portion 3 and the lower drooping portion 4 hang down into the sea during larval childcare.

  Therefore, according to the trap nursery apparatus A of the first embodiment, when coral eggs and larvae are collected, as shown in FIG. Towed up to the upper part of the seabed, moored the buoyancy imparting body 1 with means such as rope and towing, and opened the four lower drooping parts 4 from the upper cylindrical part 3 of the area partitioning member 2 to open the bottom of the seabed. The target coral 8 is hung up to the vicinity of the target coral 8, and a collection area for collecting the eggs and larvae that are spawned and floated is formed above the target coral 8, and the coral is laid.

  After the coral laying is finished, as shown in FIG. 3, the lower hanging part 4 of the area partition member 2 is closed to form a coral nursery area, and at the same time, the watering device 6 sprinkles near the upper part of the draft line in the nursery area. While raising eggs and larvae. The coral eggs and larvae may be maintained at the same place where the coral eggs and larvae were collected, and if necessary, such as during strong winds, they grew to a safe place or if necessary. As shown in FIG. 4, it may be towed to the field where the planula larvae are settled.

  When the planula larvae have grown to a certain extent and have come to take a search action to find the bottoming place, the trap nursery device A is towed to the field, for example, coral eggs / larvae in the field as shown in FIG. A diffusion prevention net 9 is installed to prevent the spread of larvae and protect the planula larvae from external enemies, and the hose 10 connects the nursery area of the trap nursery device A and the diffusion prevention net 9 of this field, The necessary amount of the planula larvae is fed into the diffusion prevention net 9 and the planula larvae are protected from external enemies with the diffusion prevention net 9 for about 2 to 3 days until the planula larvae settle on the bottom of the field. Like that.

[Examples 2 to 4]
6 to 8 show another embodiment of the trap childcare device of the present invention, and the trap childcare device B of the second embodiment shown in FIGS. A lower drooping portion 4 provided at the lower end of the upper cylindrical portion 3 is formed in a bellows shape, and the lower drooping portion 4 can be expanded and contracted with respect to the target coral 8.

Moreover, the trap childcare apparatus C of Example 3 shown in FIGS. 7 (a) and 7 (b) has a lower drooping portion 4 provided at the lower end of the upper cylindrical portion 3 of the area partition member 2 formed in a slide shape. The lower hanging portion 4 can be expanded and contracted with respect to the target coral 8 and is folded to close the bottom portion of the upper cylindrical portion 3.
Further, in the trap childcare device D of the fourth embodiment shown in FIGS. 8 (a) and 8 (b), the lower part of the lower hanging part 4 provided at the lower end of the upper cylindrical part 3 of the area partition member 2 is the target coral 8. It is formed so as to expand in a divergent shape in consideration of the size, and an egg / larvae collection region can be formed for a wide range of target corals 8.

  According to the trap childcare device and the trap childcare method of the present invention, when coral eggs and larvae are collected, the coral eggs and larvae that are suspended from the buoyancy imparting body to the upper vicinity of the target coral on the seabed in an open state are spawned and floated. The collection area to be collected is divided, and the bottom of the collected coral eggs and larvae is closed, and the area division member that divides the childcare area to raise the collected coral eggs and larvae is used. In addition, coral eggs and larvae that are easily damaged can be reliably collected without being damaged, and can be raised in a stable environment.

FIG. 1 is a perspective explanatory view showing a coral egg / larvae trap nursery apparatus according to Embodiment 1 of the present invention. FIG. 2 is an explanatory diagram of a use state showing a state in which coral eggs and larvae are collected by the trap childcare apparatus of the first embodiment. FIG. 3 is an explanatory diagram of the state of use showing a state in which coral eggs and larvae are raised by the trap nursery device of the first embodiment.

FIG. 4 is an explanatory diagram illustrating a state where the trap childcare apparatus according to the first embodiment is towed. FIG. 5 is an explanatory diagram illustrating a state in which the planula larvae grown in the field are supplied from the trap nursery device according to the first embodiment.

FIG. 6 (a) is an explanatory diagram of the state of use showing a state in which coral eggs and larvae are collected by the trap nursery device of Example 2, and FIG. 6 (b) is a coral by the trap nursery device of Example 2. It is explanatory drawing of the use condition which shows the state which raises the egg and the larva of this. FIG. 7 (a) is an explanatory diagram of the state of use showing the state in which coral eggs and larvae are collected by the trap nursery device of Example 2, and FIG. 7 (b) is a coral by the trap nursery device of Example 2. It is explanatory drawing of the use condition which shows the state which raises the egg and the larva of this. FIG. 8 (a) is an explanatory view of the state of use showing a state where coral eggs and larvae are collected by the trap nursery device of Example 2, and FIG. 7 (b) is a coral by the trap nursery device of Example 2. It is explanatory drawing of the use condition which shows the state which raises the egg and the larva of this.

Explanation of symbols

A, B, C, D ... Trap nursery device 1 ... Buoyancy imparting body, 1a ... Frame, 1b ... Floating, 2 ... Area partition member, 3 ... Upper cylindrical part, 4 ... Lower hanging part, 5 ... Water exchange net hole, 6 ... Watering device, 6a ... Submersible pump, 6b ... Watering hose, 7 ... Weight, 8 ... Target coral, 9 ... Diffusion prevention net.

Claims (5)

  Coral inhabiting sea area, above the target coral that is the target of egg and larvae collection, a buoyancy imparting body and a collection area attached to the buoyancy imparting body and collecting coral eggs and larvae in the bottom open state An area partition member for partitioning a nursery area for partitioning and raising a coral egg / larvae in a closed state at the bottom, and a coral egg / larvae provided at least in a part for partitioning the nursery area of the area partition member. A trap nursery device equipped with a water exchange net hole that prevents water from flowing out to the outside is arranged, and when collecting coral eggs and larvae, the above-mentioned area partitioning member is opened to the upper part near the target coral on the seabed. Coral eggs and larvae that hang down and lay eggs and float within the collection area are collected, and in the nursery section formed by closing the lower part of the above-mentioned area partition members when coral eggs and larvae are raised Direct trap nursery method of coral eggs, larvae, characterized in that the nursery egg-larvae collected coral.   The trap childcare device is provided with a watering device on its buoyancy imparting body, and this watering device draws seawater from the outside of the childcare region during coral egg and larval childcare, near the upper part of the waterline in the childcare region of the region partition member. The direct trap childcare method for coral eggs and larvae according to claim 2, wherein watering is performed.   A buoyancy imparting body that floats above the target coral that is the target of egg and larvae collection, and is attached to this buoyancy imparter, and the bottom part is released from the buoyancy imparter when collecting coral eggs and larvae. In this state, the area where the coral eggs and larvae that hang down and above the target coral on the seabed are spawned and floated is divided, and the bottom is closed when the coral eggs and larvae are collected. It is provided in the area partition member that partitions the childcare area that raises eggs and larvae, and at least the part that partitions the childcare area of the area partition member, and prevents coral eggs and larvae from flowing out of the childcare area. A coral egg / larvae direct trap childcare device characterized by having a water exchange net hole that allows water to pass through.   4. The coral egg / larvae direct trap childcare device according to claim 3, wherein the buoyancy imparting body is provided with a watering device for drawing seawater from outside the childcare region and sprinkling water near the upper part of the draft line in the childcare region of the region dividing member. .   The area partitioning member is provided at the upper cylindrical part that divides the periphery of the childcare area at the upper part, and at the lower peripheral edge of the upper cylindrical part, and when collecting coral eggs and larvae, at least when the bottom part is open, near the target coral on the seabed The lower hanging part which hangs down to the upper part and divides the collection area, and closes the bottom part of the upper cylindrical part at the time of coral egg / larvae childcare and demarcates the childcare area. Direct trap childcare equipment for coral eggs and larvae.

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