AU2015202133B2

AU2015202133B2 - An artificial reef structure

Info

Publication number: AU2015202133B2
Application number: AU2015202133A
Authority: AU
Inventors: Brad Adams
Original assignee: Ocean Grown Abalone Ltd
Current assignee: Rare Foods Australia Ltd
Priority date: 2014-04-24
Filing date: 2015-04-24
Publication date: 2018-12-13
Anticipated expiration: 2035-04-24
Also published as: AU2015202133A1

Abstract

Disclosed is an artificial reef structure 10 which is configured to be submerged in, and reside on a floor of, a body of water. The structure comprises plurality of alternating 5 primary walls 12p and shorter secondary walls 14s joined side by side to form an enclosure 16. In other words, the primary walls 12p and secondary walls 14s form a ring-like structure having a polygonal horizontal cross-section. Also disclosed is a system for ranching abalone and a method of ranching abalones using the artificial reef structure. flyb 1/ a-6 3La

Description

AN ARTIFICIAL REEF STRUCTURE

Field

The disclosure relates to an artificial reef structure for marine animals, such as, but not limited to, abalone, and a method of manufacturing the artificial reef structure. The disclosure also relates to a method and system for ranching marine animals using an artificial reef structure.

Background io Farming or ranching marine animals can be described as an aquaculture technique involving raising juvenile marine animals in an onshore facility. The marine animals may be ranched for various purposes, such as breeding and human consumption. In the latter case, the marine animals may be reared on the onshore facility until they reach maturity or a desirable size for harvesting. Onshore ranching facilities provide ready access to the marine animals in comparison to the natural habitat of the marine animal. Further, onshore facilities also provide control over the size, location and quantity of the marine animals, which is particularly useful for commercial scale ranching.

Onshore ranching facilities for abalones may require the pumping of large volumes of seawater each day into undercover tanks. The health and growth of such farmed abalones, however, may be considered sub-optimal compared to abalones that grow in natural habitats.

Any references to background art do not constitute an admission that the art forms a part of the common general knowledge of a person of ordinary skill in the art. The above references are also not intended to limit the application of the process and the system as disclosed herein.

Summary

The present invention seeks to provide an alternative to the above described onshore ranching facilities. Various aspects and embodiments of the invention are directed towards a method and system involving raising juvenile abalone in captivity in an

2015202133 27 Nov 2018 onshore aquaculture facility, and releasing the juvenile abalone into a body of water in the vicinity of the artificial reef structure which the juveniles subsequently colonise and from which they grow to maturity. In this manner, the abalone may reach maturity with minimal human intervention until they reach a suitable size for harvest. The site of the 5 habitat may be selected such that the nutritional and biological requirements for the good health and growth of the abalone are met. Thus, the survival rates of the abalones may also be increased.

In a first aspect there is provided an artificial reef structure to be located in a body of io water, the artificial reef structure comprising:

a plurality of alternating primary walls and secondary walls joined side by side at respective wall edges to form an enclosure, the average side-to-side length of each secondary wall being shorter than the average side-to-side length of each primary wall, the enclosure being supported on a floor of the body of water by respective lower 15 edges of the alternating primary walls, wherein the plurality of walls are tapered inwardly to define a top opening in the enclosure.

The provision of an artificial reef structure may allow for protection of the abalone from predators that are too large to enter the structure, whilst also providing adequate 20 surface area for abalone growth over a prolonged period. The inwardly tapered walls may contribute to sheltering the abalone from strong currents and/or predators. An accessible artificial reef structure may also be readily maintained by divers. For example, predators and other colonizing animals that are found on or in the structure may be readily removed by divers during periodic checks.

The primary walls may comprise at least one aperture. The secondary walls may comprise a gateway comprising a cut out in a lower portion of the secondary wall. The at least one aperture and gateway of the primary and secondary walls may allow for flow of seawater currents through the artificial reef structure, in order to maintain 30 continuous replenishment of oxygen and nutrients to the colonized artificial habitat.

In a second aspect the present invention provides a system for ranching abalone, comprising:

the artificial reef structure according to the first aspect, located in a body of 35 water suitable for nurturing abalones to maturity;

2015202133 27 Nov 2018 a hatchery in which juvenile abalones are reared; and a transportation device, wherein the juvenile abalones can be transported from the hatchery to the artificial reef structure.

In a third aspect of the present invention there is provided a method of ranching abalones using the artificial reef structure according to the first aspect, wherein the artificial reef structure is located in a body of water suitable for nurturing abalones to maturity, the method comprising:

rearing juvenile abalones in a hatchery;

io transporting the juvenile abalones from the hatchery to the artificial reef structure;

allowing the juvenile abalones to colonise the artificial reef structure and grow to maturity; and removing the mature abalones from the artificial reef structure when the mature is abalones have reached a desired size.

In a fourth aspect there is provided a method of manufacturing an artificial reef structure to be located in a body of water, the method comprising:

forming a body of the artificial reef structure, comprising a plurality of alternating primary walls and secondary walls joined side by side at respective wall edges to form an enclosure, the enclosure being supported on a floor of the body of water by respective lower edges of the alternating primary walls, wherein the average side-toside length of each secondary wall is shorter than the average side-to-side length of each primary wall, and wherein the plurality of walls are tapered inwardly to define a top opening in the enclosure.

In one embodiment, forming the body of the artificial reef structure comprises casting a settable material in a mould having a cavity defining alternating primary walls and shorter secondary walls joined side by side to form an enclosure, wherein the plurality 30 of walls are tapered inwardly to define a top opening in the enclosure.

In a fifth aspect there is provided a mould for carrying out the method according to the fourth aspect.

Brief Description of the Figures

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Notwithstanding any other forms which may fall within the scope of the abalone habitat reef and system as set forth in the Summary, specific embodiments will now be described, by way of example only, with reference to the accompanying figures in which:

Figure 1 is a perspective view of one embodiment of an artificial reef structure.

Figure 2 is a top view of the artificial reef structure shown in Figure 1.

Figure 3 is a bottom view of the artificial reef structure shown in Figures 1 & 2.

io Figure 4 shows one embodiment of a system for ranching abalones using an artificial reef structure.

Figure 5 is a side view of a transportation device employed in the system shown in Figure 4.

Figure 6 is a perspective view of the transportation device shown in Figure 5.

Figure 7 is a flow chart illustrating a method for ranching abalones using an artificial reef structure.

Detailed Description

An artificial reef structure 10 will now be described with reference to providing an 20 artificial habitat for aquaculture of marine animals, in particular abalone.

Figures 1 and 2 show an artificial reef structure 10 which is configured to be submerged in, and reside on a floor of, a body of water. The body of water may be fresh water or saline water, including but not limited to, an ocean, a sea, a bay, an 25 estuary, a river, or a lake. Depending on the nature of the body of water, the floor may be a seabed, river bed, lake bed or other sub-aqua stratum.

In general, the structure 10 has sufficient density to reside on the floor of the body of water. It will be appreciated, however, that some embodiments of the structure 10 may 30 be configured to be tethered or anchored to the floor of the body of water.

The structure 10 provides an alternative habitat to the natural reefs in the ocean in which marine animals such as abalone would otherwise live. Abalones are reefdwelling marine snails that attach and move on surfaces. The structure 10 offers a

2015202133 27 Nov 2018 habitat in natural ocean surroundings for the abalones to live and grow, providing the nutritional and biological requirements for good health and growth of the abalone, whilst also seeking to provide some form of protection against predators and a significant surface area for abalones to populate.

Typically, the site of the artificial reef structure 10 is to be located in a body of water where the following environmental factors are met:

• the site is surrounded by seagrass beds having epiphytic red algae;

• the site is protected from severe swell events by reef or island chain; and · the site is at a depth to allow for extended dive times, typically 15-18 m in depth.

The artificial reef structure 10 comprises a plurality of alternating primary walls 12p and shorter secondary walls 14s joined side by side to form an enclosure 16. In other 15 words, the primary walls 12p and secondary walls 14s form a ring-like structure having a polygonal horizontal cross-section. In the embodiment shown in Figures 1 and 2 there are three primary walls 12p¹, 12p² and 12p³, and three secondary walls 14s¹, 14s² and 14s³. However it will be appreciated that the enclosure 16 may comprise any suitable number (n) of walls such that the order of walls appear as 12p¹, 14s¹, 12p², 20 14s², 12p³, 14s³, ..., 12^pn, 14^sn, which is adjacent to 12^p1. When n is an odd number >1, the primary walls 12p are diametrically opposed to the secondary walls 14s in the enclosure 16.

As can be seen in Figure 2, the structure 10 has three-fold symmetry about dotted 25 lines X1, X2 and X3. It will be appreciated, however, that the structure 10 is not limited to three-fold symmetry and a structure 10 with a greater number (n) of walls 12p and

14s will result in the structure having an increased number of lines of symmetry.

All primary walls 12p have the same dimensions as one another and are generally 30 trapezoidal. All secondary walls 14s have the same dimensions as one another and are generally trapezoidal. Each secondary wall 14s has an average length L1 shorter than an average length L2 of each primary wall 12p.

The primary and secondary walls 12p, 14s have base lengths B2 and B1 respectively, 35 which are wider than their top lengths T2 and T1 respectively. Thus, the artificial reef

2015202133 27 Nov 2018 structure 10 can also be described as having a pyramid-like shape. In particular, in this embodiment, the structure 10 can be described as having a hexagonally-based pyramid-like shape. When the structure 10 is located in a body of water, for example on a floor of the ocean, the structure 10 stands supported by a bottom edge 21 of each 5 primary wall 12p along the entire base length B2 of each primary wall 12p, or at least a substantial portion of the base length B2. This configuration contributes to the stability of the structure 10 on the floor of the ocean or body of water.

The plurality of walls 12p and 14s are tapered inwardly towards a top portion of the io enclosure 16 to define a top opening 18. Thus, from the top view shown in Figure 2, the top opening 18 is defined by top edges 20 of the plurality of walls. Therefore, the top opening 18 has the appearance of a triangle having sides formed by the top edges 20a of the primary walls 12p, with truncated corners formed by the top edges 20b of the secondary walls 14s. The tapering of the plurality of walls 12p and 14s provide for 15 a more enclosed shelter for the abalone compared to a case where the walls are not tapered. The resulting pyramid-like structure also contributes to the stability of the structure 16, which will be discussed in more detail below. The top opening 18 may be particularly useful for a diver to reach into and gain access to an interior of the enclosure 16, for example, to retrieve abalone or to remove predators and/or 20 undesirable biomaterials from the enclosure 16.

Each primary wall 12p comprises at least one aperture 24. In this embodiment, three rectangular apertures 24 are shown to be horizontally aligned with each other on the primary walls 12p. Two outermost apertures are shown with a height greater than their 25 width and one aperture between the two outermost apertures are shown to be substantially square. However, it will be appreciated that the structure 10 may comprise any suitable number of apertures with any suitable shape in any suitable configuration on the primary walls 12p.

Further, in this embodiment each secondary wall 14s comprises a gateway 26. The gateway 26 comprises a cut-out in a lower portion of the secondary wall 14s. The gateway 26 is defined by side edges 28 and a top edge 30 such that the cut-out is similar in shape to the secondary walls 14s but is a smaller scale. The area of the gateway 26 in this embodiment is approximately equal if not larger than a surface area

32 of the corresponding secondary wall 14s. In this embodiment, the gateway 26 is

2015202133 27 Nov 2018 also bottomless. In other words, a bottom edge 23 of the corresponding secondary wall 14s does not span the total base length B1 of the secondary wall. However, it will be appreciated that the shape of the gateway 26 is not limited to the shape herein described, and may not be bottomless.

Referring now to Figure 3, the structure 10 may comprise at least one support member extending from an inner surface 36 of the primary walls 12p, to strengthen the enclosure and/or to provide extra surface area for the abalones to occupy. In this embodiment the support member is in the form of a column 34 extending substantially io vertically along the inner surface 36. The columns 34 may be formed integrally with or separately to the inner surface 36 of the enclosure 16. In this embodiment, each primary wall 12p comprises two columns 34 located adjacent the apertures 24. Further, a length of the columns 34 spans from the top edge 20 to the bottom edge 21 of the corresponding primary wall 12p. Each column comprises a wall 38 having opposing 15 side surfaces 40a and 40b (herein referred to as “surfaces 40”) that are substantially perpendicular to the inner surface 36. An area of the surfaces 40 may be configured to be large enough such that one or more abalones can occupy each of the surfaces 40 within the enclosure. The columns 34 also define smaller enclosed regions of space within the enclosure for abalones to seek refuge. Therefore, once populated, abalones 20 may be found within the structure 10 seated or self-attached to any part of the inner surface 36, side surfaces 40 or any other surface of the enclosure 16.

The columns 34 are also shown to have a triangular shape, wherein one side of the triangle is adjacent and abuts the inner surface 36 of the enclosure, a bottom side 44 is 25 coplanar with the bottom edge 21 of the primary walls 12s, and a remaining side 46 is substantially vertical and meets the top edge 20. Thus, the bottom side 44 may provide the structure 10 with additional stability.

Side portions 48 of the gateway 26 may also be provided with a thickness greater than 30 that of an adjacent primary wall 12p, thus forming additional wall surfaces 50.

Therefore, it can be seen (particularly in Figure 3) that a relatively enclosed region of space 52 may be defined by wall surfaces 50 of the gateways 26 and the side walls 40b, for abalones to locate or seek refuge.

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With particular reference to Figure 2, in one example, the bottom edge 21 of each primary wall 12p is parallel to the bottom edge 23 of a diametrically opposing secondary wall 14s. A length R spanning from the bottom edge 23 of secondary wall 14s³ to the bottom edge 21 of primary wall 12p² can be 1800mm - 2000mm; more 5 specifically 1905.3mm. Further, with reference to Figure 1, a vertical height H of the structure 10 from the bottom edge 21 to top opening 18 may be 800mm - 1100mm.

A system 60 for ranching abalones according to an aspect of the invention will now be described. With particular reference to Figure 4, the system 60 comprises an artificial io reef structure such as the structure 10 previously described, a hatchery 62 and a transportation device 64. The hatchery 62 and the transportation device 64 in Figure 4 are shown in phantom so as not to limit the features or appearance of the transportation device or hatchery. Juvenile abalones are reared in the hatchery until the abalones reach a threshold size or stage in their development. The juvenile 15 abalones from the hatchery 62 are then transported in the transportation device 64 from the hatchery 62 to the artificial reef structure 10 in a marine body of water 66, such as the ocean. Particular features of the system 60 will now be described in more detail.

Hatchery

As previously mentioned, juvenile abalone are reared in the hatchery 62 until they reach a predetermined threshold size to be relocated to the artificial reef structure 10. The hatchery 62 may be in the form of an onshore abalone ranch. In one example, juvenile abalone may be reared in the hatchery 62 until reaching a threshold size of 25 35mm - 45mm. More specifically, according to one embodiment of the present invention, it has been found an optimum size for the release of juvenile abalone from the hatchery to the ranch is approximately 40mm. This size is considered to be when abalone are sufficiently mature to start consuming the preferred macro-algae available in the ocean and are also large enough to protect themselves from certain predators, 30 such as fish. On the other hand, abalone of a larger size than approximately 40mm would present logistical difficulties for transport to the artificial reef structure 10, such as decreasing the number of abalones that may be transported in the transportation device 64. The hatchery 62 may be 500km - 600km from a location of the artificial reef structure 10 in the marine body of water 66.

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Transportation Device

Juvenile abalone that have reached the threshold size in the hatchery 62 may then be placed in a transportation device 64 at the hatchery 62, before embarking on a journey in the transportation device 64 that could take several hours. One of the challenges 5 during this journey is the mortality rate of the juvenile abalone. Typically, live marine animals that are to be moved significant distances are transporting on vehicles within sizeable transporting tanks designed for the task, such as the FISH PAC ® live fish transportation systems. According to one embodiment of the present invention, the survival rate of abalone transported in these tanks increases if the abalone are first io placed in the transportation device 64 and then placed in the transporting tanks.

With reference to Figures 5 and 6, in one embodiment the transportation device may in the form of a container 64 comprising a body 68 having opposing end portions 70 and 72, wherein at least one of the end portions has a door 74 to allow for juvenile 15 abalones to enter and exit the container. In this embodiment the container 64 has two opposing end portions 70 and 72. Only the end portion 70 comprises a door 74, however in another embodiment both end portions 70 and 72 may comprise a door. The door 74 can more clearly be seen in Figure 6 where the door 74 is shown to be open.

The body 68 may also comprise cylindrically curved portions. In other words, the body may have a cylindrical or elliptical cross-section. In the embodiment shown in Figures 5 and 6 the body 68 is shown to be in the form of a drum having an elliptical cross-section. The container 64 may be configured such that its body 68 is 25 transportable in a horizontally lengthwise manner.

The container 64 also comprises liquid permeable material. More specifically, the container 64 is made of plastics material in the form of a mesh. Therefore, liquid such as water can flow through the apertures 76 of the mesh into the container 64, but 30 abalones in the container 64 are retained. The door 74 has also a mesh or cage-like form, but in any case allows water to flow through the door 74 into the container 64 without allowing abalones to exit the container 64 unless the door 74 is opened.

With particular reference to Figure 6, the container also comprises a divider 78. The 35 divider 78 comprises two intersecting panels 80 and 82 that are substantially

2015202133 27 Nov 2018 perpendicular to each other. The two intersecting panels 80 and 82 subsist in orthogonal planes that intersect at a common central axis 84. The intersecting panels 80 and 82 fit into the container such that their common axis 84 is disposed lengthwise into the body 68 of the container 64. The intersecting panels form four sub5 compartments A, B, D and D, and provide additional surface area (i.e. the surfaces of the intersecting panels) for abalone to attach to. This allows for juvenile abalone to more comfortably situate in the container 64 during the journey between the hatchery 62 and the artificial reef structure 10. The divider 78 may also allow for a greater number of juvenile abalones to be transported in the container 64 than if the divider 78 io was not used. In one embodiment, 150-250 juvenile abalones may be transported in the container 64. More specifically, around 200 juvenile abalones may be transported in the container 64.

Artificial Reef Structure

Any suitable artificial reef structure may be used for the system 60. However, in the embodiment shown in Figure 4, the artificial reef structure 10 previously described is incorporated in the system 60.

The transportation device or container 64 may be taken to the structure 10 by a diver, 20 and placed in close proximity to the structure 10 for the juvenile abalones within the container 64 to migrate into the structure 10. More specifically, the diver may place the container 64 on, inside (for example, through the top opening 18), or otherwise in contact with or adjacent to the structure 10. The diver may then attach the container 64 to the structure 10 with an attachment device, such as an elongate member, lanyard or 25 strong elastic band. One or more containers 64 containing juvenile abalone may be attached to the structure 10 at one time.

The juvenile abalone may be given a suitable length of time inside the container 64 to settle in and recover from the stressful transition from the harvest 64 in the hatchery 30 62. In one embodiment of the system 60, 2-3 days is sufficient for the juvenile abalone to settle and recover. Once the abalone have settled, the door 74 may of the container 64 may be opened to allow the juvenile abalone to move out of the container 64 and into the enclosure 16 of the structure 10. In one embodiment, the juvenile abalones may be given 5-7 weeks, or more specifically up to 6 weeks, to crawl out of the 35 container 64 into the structure 10. The juvenile abalones that have been transferred to

2015202133 27 Nov 2018 the artificial reef structure continue to grow and be nurtured by the marine water surroundings until maturity.

Throughout the growth period of the abalone within the structure 10, monitoring and maintenance of the structure may be required. It has been found that over a three year period of growth for the abalone within the artificial reef structure 10, up to 50% of the abalone may not survive due to predators, such as octopi, or natural causes. The structure 10 may also be “polluted” by unwanted biomaterials, for example, as a result of colonisation by other marine creatures such as ascidians, small oysters, soft corals, io white worm, sandworm and kelp. While these unwanted biomaterials may be harmless to the abalone, such colonisation reduces the surface area within the structure 10 available for growth of the abalone. Accordingly, divers may monitor the structure 10 by virtue of periodic visitation, and the structure 10 can be maintained by removing deceased abalone, predators and unwanted biomaterials.

Once the juvenile abalone in the artificial reef structure 10 have matured and reached a desired size, the abalone may be harvested/removed from the structure 10. It has been found that at certain marine locations a maximum stocking density of 2kg/m² of surface area of the structure 10 just prior to harvest of the abalone can provide for 20 good growth and low natural mortality. Thus, juvenile abalones may be initially stocked on each artificial reef structure 10 to provide for a stock density of 2kg/m² of the structure 10 at harvest.

With particular reference to Figure 7, a method 90 for ranching abalones according to 25 an aspect of the invention will now be described. The method 90 comprises use of an artificial reef structure, which may be any artificial reef structure suitable for locating in a body of water, particularly a marine body of water, in which abalones may be nurtured. In this embodiment, the method 90 uses of the artificial reef structure 10 previously described. The method 90 comprises the following steps:

Step 92: rearing juvenile abalones in a hatchery.

Step 94: transporting the juvenile abalones from the hatchery to the artificial reef structure.

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Step 96: allowing the juvenile abalones to grow in the artificial reef structure to maturity.

Step 98: removing the mature abalones from the artificial reef structure when 5 the abalones have reached a desired size.

Step 92 may involve rearing the juvenile abalones in the hatchery until the juvenile abalones are 35mm-45mm in size, or more specifically 40mm in size. The hatchery may be the hatchery 62 of the system 60 previous described, such as an onshore io abalone ranching facility.

Step 94 may involve transporting the juvenile abalones in the transportation device or container 64, previously described in relation to the system 60. 150-250 juvenile abalones may be transported in the container. More specifically, with additional 15 reference back to Figures 5 and 6, step 94 may further comprise using a container 64 having a body 68 with opposing end portions 70 and 72, wherein at least one of the end portions has a door 74 to allow for abalones to enter and exit the container, the body 68 comprising liquid permeable material. Thus, step 94 may also comprise loading the container 64 at the hatchery 62 by opening the door 74 of the at least one 20 end portion 70 or 72, moving or otherwise locating juvenile abalone that have attained a threshold size inside the container 64, and closing the door 74.

Step 94 then involves taking the container 64 to the artificial reef structure 10 in the body of water. This may involve locating the container 64 in a live transporting tank 25 situated and movable on a transporting vehicle for the journey between the hatchery and the artificial reef structure 60. The journey may involve a distance of 500km 600km. The container 64 may be brought to the specific site of the structure 10 by divers.

Step 94 may then involve attaching the container 64 to the artificial reef structure 10 for a period of time such as 2-3 days to allow the juvenile abalones in the container 64 to settle. This may involve attaching the container 64 to the structure using an attachment device such as an elongate member or strong elastic band. Once the juvenile abalone have settled, step 94 further involves opening the door 74 of the container 64 so that the juvenile abalones within the container 64 may move out and into the structure 10.

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This step may comprise leaving the door 74 of the container open for 5-7 weeks to allow for all the juvenile abalones in the container 64 to relocate and settle into to the artificial reef structure 10. Throughout this step, divers may monitor and check the progress of the juvenile abalone. Once all juvenile abalone have exited the container 5 64, a diver may retrieve the container 64 from the body of water.

Step 96 of the method 90, of allowing the juvenile abalone to grow in the artificial reef structure to maturity, is then carried out. Step 96 may further comprise the steps of periodic monitoring of or regularly checking the artificial reef structure 10 during the io time of growth of the abalones. The step 96 may also subsequently comprise maintaining the structure 10 during the period of growth for the abalones, by performing removing predators from the artificial reef structure and/or removing undesirable biomaterials from the artificial reef structure, such as other marine creatures that colonise the structure 10.

Finally, the method 90 comprises step 96 of removing mature abalone from the artificial reef structure 10 when the abalone have reached a desired size. That desired size may be 110-150mm.

A method of manufacturing an artificial reef structure according to another aspect of the invention will now be described. The method comprises forming a body of the artificial reef structure, comprising a plurality of alternating primary walls and shorter secondary walls joined side by side to form an enclosure, wherein the plurality of walls are tapered inwardly to define a top opening of the enclosure. The method may be used to manufacture the artificial reef structure 10 previously described. The method may comprise manufacturing the artificial reef structure with material that has sufficient density to sink to a floor of a particular region in a marine body of water.

The method may comprise forming the body of the artificial reef structure by injection 30 moulding. For example, the body may be made of fibre glass. Alternatively, the method may comprise forming the body by concrete casting, for example, by utilising formwork.

The method may comprise forming at least one aperture in primary wall and/or forming a gateway in each secondary wall of the artificial reef structure. This may comprise 35 cutting the plurality of alternating walls. In other words, the body of the artificial reef

2015202133 27 Nov 2018 structure may first be formed with solid, continuous primary and secondary walls, and then the at least one aperture or gateway may be formed in the primary and secondary wall respectively by cutting into the walls.

Alternatively, the method may be carried out using a mould defining a cavity for forming the plurality of alternating primary and secondary walls, and filling the mould with settable material. Further, the mould may comprise a plurality of spacers in the cavity that correspond in shape to the at least one aperture in each primary wall and the gateway in each secondary wall. Thus, after the mould is filled with settable io material and sets, the method produces the artificial reef structure having the at least one aperture and gateway. The settable material may for example by concrete.

It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments 15 without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive. For example, regarding the artificial reef structure 10, instead of being in the form of columns, the support members 34 may be extend horizontally along the inner surface 36 of the structure 10. In other words, the support member may be 20 parallel to the bottom edge of the corresponding primary wall 12p.

In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” is 25 used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

Further, with regard to the various means referred to throughout the specification, any 30 means is to be understood as encompassing individual as well as plural structures that may or may not be physically connected.

Claims

CLAIMS:

1. An artificial reef structure to be located in a body of water, the artificial reef structure comprising a plurality of alternating primary walls and shorter

2. The artificial reef structure of claim 1, wherein the enclosure comprises diametrically opposing primary and secondary walls.

15

3. The artificial reef structure of claim 1 or 2, wherein one or both of:

a) each primary wall has at least one aperture for water to flow through the artificial reef structure; and

b) each secondary wall comprises a gateway, the gateway area optionally being larger than an outer surface area of the secondary wall.

4. The artificial reef structure of claim 3, wherein each primary wall comprises at least one support member extending from an inner surface of the primary wall.

5 material such as by one of injection moulding or concrete casting.

5 end portions has a door to allow for abalones to enter and exit the container, the body comprising liquid permeable material.

5 a transportation device, wherein the juvenile abalones from the hatchery can be transported from the hatchery to the artificial reef structure.

5. The artificial reef structure of claim 4 wherein the at least one support member is

25 located adjacent the at least one aperture and comprises a surface area substantially perpendicular to the inner surface of the primary wall.

5 secondary walls joined side by side at respective wall edges to form an enclosure, the average side-to-side length of each secondary wall being shorter than the average side-to-side length of each primary wall, the enclosure being supportable on a floor of the body of water by respective lower edges of the alternating primary walls, wherein the plurality of walls are tapered inwardly to io define a top opening in the enclosure.

6. The artificial reef structure of any one of the preceding claims comprising three primary walls and three secondary walls such that the enclosure has three-fold

30 symmetry.

7. The artificial reef structure of any one of the preceding claims, wherein the primary walls have the same dimensions and/or the secondary walls have the same dimensions.

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8. A system for ranching abalone, comprising:

the artificial reef structure of any one of claims 1-7, located in a body of water suitable for nurturing abalones to maturity;

a hatchery in which juvenile abalones are reared; and

9. The system of claim 8, wherein the transportation device is a container comprising:

io a body having opposing end portions, at least one of the end portions having a door to allow for juvenile abalones to enter and exit the container.

10. The system of claim 9 wherein the container comprises a plurality of inner compartments, and wherein the body comprises liquid permeable material, with

11. The system of any one of claims 8-10, further comprising an attachment device capable of attaching the transportation device to the artificial reef structure.

20

12. A method of ranching abalones using the artificial reef structure of any one of claims 1-7, wherein the artificial reef structure is located in a body of water suitable for nurturing abalones to maturity, the method comprising: rearing juvenile abalones in a hatchery;

transporting the juvenile abalones from the hatchery to the artificial reef

25 structure;

allowing the juvenile abalones to grow in the artificial reef structure to maturity; and removing the mature abalones from the artificial reef structure when the abalones have reached a desired size.

13. The method of claim 12 comprising: rearing the juvenile abalones in the hatchery until the abalones are 35mm-45mm in size, such as substantially 40mm in size.

14. The method of claim 12 or 13, comprising: removing the mature abalones from

35 the artificial reef structure when the abalones are 110-150mm in size.

2015202133 27 Nov 2018

15. The method of any one of claims 12-14, wherein transporting the juvenile abalones from the hatchery to the artificial reef structure comprises using a container having a body with opposing end portions, wherein at least one of the

15 the body optionally comprising cylindrically curved portions.

16. The method of any one of claims 12-14, wherein transporting the juvenile abalones from the hatchery to the artificial reef structure comprises:

io at the hatchery, opening the door of the at least one end portion, locating juvenile abalones of a threshold size inside the container, and closing the door; taking the container to the artificial reef structure in the body of water; attaching the container to the artificial reef structure for 2-3 days to allow the juvenile abalones in the container to settle.

17. The method of claim 16, further comprising:

opening the door of the at least one end portion of the container to allow the juvenile abalones in the container to relocate from the container to the artificial reef structure, such as by leaving the door of the container open for 5-7 20 weeks to allow for all the juvenile abalones in the container to relocate and settle into to the artificial reef structure.

18. The method of any one of claims 12-17, further comprising:

when the artificial reef structure is populated by abalones, regularly

25 checking the artificial reef structure, and performing either or both of:

removing predators from the artificial reef structure; and removing undesirable biomaterials from the artificial reef structure.

19. A method of manufacturing an artificial reef structure to be located in a body of

30 water, the method comprising:

forming a body of the artificial reef structure, the body comprising a plurality of alternating primary walls and secondary walls joined side by side at respective wall edges to form an enclosure, wherein the average side-to-side length of each secondary wall is shorter than the average side-to-side length of each primary

2015202133 27 Nov 2018 wall, and wherein the plurality of walls are tapered inwardly to define a top opening of the enclosure.

20. The method of claim 19, wherein the body is formed by moulding a settable

21. The method of claim 19 or 20, wherein the artificial reef structure that is formed is configured as set forth in any one of claims 2-7.

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22. A mould for carrying out the method of any one of claims 19-21.