WO1999060844A2

WO1999060844A2 - Lobster ranching methods and structures

Info

Publication number: WO1999060844A2
Application number: PCT/US1999/011243
Authority: WO
Inventors: Haves Reynolds White, Jr.
Original assignee: White Haves Reynolds Jr
Priority date: 1998-05-28
Filing date: 1999-05-21
Publication date: 1999-12-02
Also published as: WO1999060844A3; AU4195399A

Abstract

Methods and structures are provided for enhancing marine habitats for lobster and crab ranching (10). According to a first aspect of the invention, predators of at least adult lobster are excluded from a ranching area (14). According to a second aspect of the invention, the method includes arranging a plurality of artificial shelters (20) in at least one zigzag hedgerow (22), preferably parallel to normally prevailing ocean currents (22, 24). According to further aspects, the methods include providing artificial shelter (20) for at least the large juvenile and adult lobster at a marine location; providing an artificial benthic habitat for benthic phase juvenile lobster within at the marine location; and/or providing a settlement and nursery habitat for early benthic phase juvenile lobster to the marine location. According to a still further aspect, the methods preferably include vertically integrating the artificial shelter (20), the artificial benthic habitat, and the settlement and settlement habitat.

Description

LOBSTER RANCHING METHODS AND STRUCTURES

TECHNICAL FIELD This invention relates to methods of lobster ranching and suitable structures for use in lobster ranching. The methods and structures can also be used in crab ranching.

BACKGROUND OF THE INVENTION Spiny lobster, also known as rock lobster, are among the world's most highly prized seafood. The fisheries for spiny lobster are under severe pressure. In addition, consumer demand and market value remain extremely high. The supply of lobster, because of its market value, is falling faster than most other fishing industry produce. Fishing for lobster in deeper, more remote environments is difficult and expensive. Increasingly, spiny lobster must be harvested over wide areas by skin divers or scuba divers, which is time consuming and expensive. The demand is so great that controls on lobster fishing are sometimes circumvented. For example, if small, immature lobster are caught, they are often sold in the black market or used as live attractants rather than being returned to nature. Part of the world market places a premium on 350 - 450 g (12-16 ounce) lobster, which is smaller than the average size at maturity for reproduction. The use of these small, immature lobster exacerbates the effects due to fishing.

The farming of spiny lobster in on-shore fish tanks has long been suggested as a solution to the problem of providing commercial quantities of spiny lobster. However, more than fifty years of research and efforts directed to lobsterfarming have failed to solve the many biological and technical difficulties. Spiny lobster (Crustacea: Decapoda: Palinuridae) include many different species, such as Panulirus argus, Panulirus cygnus, Panulirus japonicus, and Jasus edwardsii. For example, Panulirus argus is a shallow water lobster, which can live in water as shallow as 2-3 meters (6-10 feet). Furthermore, this is a warm water species with an attendant high growth rate. The known ecology and fishery biology of spiny lobster is described and summarized in the recent reference book: Spiny Lobster Management. Edited by B.F. Phillips, J.S. Cobb, and J. Kittaka, Blackwell Scientific Publications 1994, a copy of which is filed herewith and which is incorporated herein by reference in its entirety. As described in this reference work, the life-cycle of spiny lobster is complex, involving at least five major stages of development, those being: (1) adult; (2) egg, (3) phyllosoma (larval stages), (4) puerulus (postlarval stages), and (5) juvenile. Each of the major stages of the life cycles requires a different marine habitat and ecological requirements, and the different species of spiny lobster may also prefer or require different marine environments at one or more stages of the life-cycle. Adult spiny lobster frequently aggregate during the daylight hours in crevices of coral and rocky reefs. They aggregate at high density to help protect themselves from predators. Density-related diseases are not usually a problem in the lobster's natural healthy environments, in part due to adequate flushing of water. At sunset, the adult lobster emerge from their dens to forage nocturnally in nearby habitats such as reef flats and seagrass beds. Of course, it is the adult spiny lobster that is the most commercially valuable, and fishing or harvesting takes place primarily in the rocky reef habitats of the adults and the bay or lagoon habitats of the larger juveniles. Egg masses are usually extruded, fertilized, spawned, and hatched in the spring and summer by females in these types of offshore reef areas.

The phyllosomes (larval stages) are transported offshore by wind-driven surface currents into oceanic habitats. The phyllosomes are dorsoventrally flattened, transparent, and leaf-like larvae and are adapted for passive transport with the ocean currents and feeding on free-floating plankton. There are usually 7-13 phyllosoma stages, with each representing one or more instars. The total duration of the larval stages differ greatly among spiny lobster species, ranging from a few months up to almost two years.

At the end of the last larval stage, when the larva is about 35 mm in length, the phyllosome metamorphoses to the puerulus stage (postlarval or "PL" stage), which is a transparent, free-swimming, non-feeding stage that navigates to move inshore where it searches for a suitable settlement and nursery habitat by means of a complex receptor system formed by the antennae and a pinnate setal system, which enables orientation to cues associated with coastlines. A suitable settlement and nursery habitat is usually characterized as structurally complex. For example, an ideal settlement environment for the spiny lobster species Panulirus japonicus and Panulirus argus is red algae. This type of settlement environment provides protection from predators and also provides an environment with abundant food sources. Once settled in this type of settlement habitat, the postlarval stage of the spiny lobster metamoφhoses into the juvenile stage.

The juvenile stage can be further divided into two ecologically distinct phases - an early benthic phase and a later benthic phase. During the juvenile stage, the lobster undergo about five moults as they grow. For example, small, early benthic phase juvenile lobster of the species Panulirus argus, which are less than about 15 mm in carapace length, typically live in the settlement habitat, such as in or under large clumps of intricately branched red algae, which provide food and refuge. Similarly, small early benthic phase Panulirus cygnus occupy very small holes on the face, in ledges, and in caves on coastal limestone reefs, particularly those holes with associated seagrass or algae.

As the juvenile lobster grow and reach 15 - 20 mm in carapace length, these later benthic phase juveniles begin to move out of algal clumps to larger, appropriately-sized crevices in algae-covered rock rubble. The later benthic phase lobster search for suitable protective crevices based on their growing size. As the juvenile lobster continue to grow, they must move several times from one hiding place in search of another, slightly larger hiding place. During these moves, the lobster can be particularly vulnerable to predation. A suitable benthic habitat should have a wide range of different sized crevices for the growing lobster to choose from. These types of habitats are referred to herein as "benthic" habitats.

As the later benthic phase juvenile lobster continue to grow larger, they become gregarious in larger dens formed by rocky outcrops, coral heads, sponges, limestone solution holes and undercut bands of seagrass beds. Toward the end of the juvenile stage, shortly before reaching adulthood, the large juvenile lobster move from the benthic habitats to the reef habitats of the adults.

It is to be understood that the juvenile lobster moult several times as they grow, and that as the juvenile stage lobster grow, they look for appropriately-sized protective spaces to live in. There is no sharp dividing line between one habitat and the next; the juvenile lobster grow on a continuum. Thus, the lobster migrate from one protective habitat to the next, essentially from one protective crevice to another slightly larger crevice. Particularly for the more vulnerable juvenile lobster, a range of different sized hiding places are required. A growing lobster that cannot find a larger, suitably-sized hiding place will likely soon fall to predation. On the other hand, if a crevice is much too large for the juvenile lobster, it will not offer adequate protection. A major limitation on the growth of spiny lobster populations is believed to be natural predation of post-larval (PL), juvenile and small adult lobster by sharks and finfish. It is estimated that such predation may account for more than ninety-seven percent (97%) of lobster mortality. Losses due to natural predators are reduced when the lobster have adequate physical protection and shelter in rocks and crevices, either natural or artificial. Experiments show that the abundance of spiny lobster increases significantly in sites augmented with artificial shelter for adult lobster, but not in control sites, when the sites are not limited by food or postlarval availability. For example, up to 264 spiny lobster were collected from a single low-relief artificial habitat measuring only about 2 meters by 1.5 meter. Of course, these expeπments are subject to the migratory tendencies of spiny lobster, certain species of which have been observed to migrate in queues of up to sixty-four lobster, moving both day and night for two to three days. These migrations have been variously associated with reproduction, redistribution of juveniles to adult habitats, and/or avoidance of physically stressful environmental conditions.

It can be observed that the life-cycle of the spiny lobster is highly complex; each stage of the life cycle requires a different environment. These natural habitats and the complex interrelation of these environments have thus far been practically impossible to simulate in land-based artificial tanks for lobster farming. Thus, there has been a long-felt need for methods and structures for use in promoting populations of lobster, which methods are referred to herein as lobster ranching.

SUMMARY OF THE INVENTION Methods of promoting lobster and crab population densities and methods of lobster ranching are provided. According to a first aspect of the invention, predators of juvenile and adult lobster are excluded from a ranching area at a marine location. According to a second aspect of the invention, the method includes arranging a plurality of artificial shelters in at least one zigzag hedgerow. Other aspects of the invention include providing artificial shelter for at least the large juvenile and the adult lobster at a marine location; providing an artificial benthic habitat for later benthic phase juvenile lobster within at the marine location; and/or providing an artificial settlement and nursery habitat for the settlement of PLs and early benthic phase juvenile lobster to the marine location. According to a further aspect, the methods preferably include vertically integrating the artificial shelter, the artificial benthic habitat, and the artificial settlement and nursery habitat. According to a still further aspect, the methods include capturing puerulus from the ocean; protecting the captured puerulus in a puerulus moult facility until at least the first instar moult into early benthic phase juveniles; and transplanting the juveniles to the marine location. The methods additionally include harvesting of the lobster or crab product. The various aspects of the invention are best used together to achieve a cumulative or synergistic enhancement of lobster populations at a marine location.

According to further aspects of the invention wherein suitable structures are provided for practicing the methods, predators can be excluded from a ranching area by using one or more predator-exclusion sections to isolate a marine habitat for juvenile and adult lobster or crab. This physically protected enclosure is created to help protect juvenile and adult lobster from natural predators such as sharks and finfish. The predator-exclusion sections of the enclosure operate on the principle of size exclusion, which should permit, modify, or enhance the flow of ocean water through the enclosure but substantially limit or prevent the entry of sharks and finfish predators of juvenile and adult lobster.

The physically protected habitat is created by forming a large enclosure in or adjacent to a part of the ocean that provides an otherwise substantially natural habitat for adult lobster. The predator-exclusion sections can be created using conventional construction techniques with any suitable materials that resist saltwater corrosion. However, according to one aspect of the invention, a high strength composite pier system is provided for holding high strength perimeter netting. According to another aspect of the invention, marine structures, such as the artificial shelters for the adult lobster, are formed using known techniques of mineral accretion, which are described in detail in U.S. Patent Nos.4,246,075; 4,440,604; and 4,461 ,684, the specifications of which are incorporated herein by reference in their entirety. It is to be understood that because of the gregarious nature of juvenile and adult spiny lobster, the methods of the present invention are most effective in the promotion of populations of these lobster. Nevertheless, it is to be understood that the same methods of the invention can be employed to promote the population with other types of lobster and some species of crab.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings are incorporated into and form a part of the specification to illustrate several examples according to the presently most preferred embodiments of the present invention. The drawings are only for illustrating preferred and alternative examples of the inventive methods and structures and are not to be construed as limiting the invention to only the illustrated and described examples. The drawings include the following figures:

FIG. 1 is a top plan view diagram of a lobster ranch according to a presently most preferred embodiment of the invention;

FIG. 2 is an enlarged top plan view diagram illustrating the micro currents generated by the arrangement of zigzag hedgerows;

FIG. 3 is a top view in partial section of a presently most preferred structure for a representative section of a predator-exclusion perimeter;

FIG. 4 is a side elevation view of the predator-exclusion section shown in FIG. 3 taken from the line 4-4 of FIG. 3, the view further illustrating a presently most preferred embodiment of a tethered prismatic volume (TPV) for implementing vertical integration in the lobster ranching operation; FIG. 5 is a side cross-section view of the predator-exclusion section shown in

FIG. 3 taken along line 5-5 of FIG. 3, the view further illustrating the presently most preferred embodiment of a tethered prismatic volume (TPV) for implementing vertical integration in the lobster ranching operation;

FIG. 6 is an end elevation view of a preferred structure for a section of a predator-exclusion perimeter with TPV shown in FIG. 4;

FIG. 7 is an end elevation view of a preferred structure for a casa and tethered prismatic volume for a settlement and nursery habitat according to the invention taken along line 7-7 of FIG. 1;

FIG. 8 is a section elevation view of a preferred structure for a puerulus moult facility for captured pueruli (PL stage);

FIG. 9 is a perspective, partial cross-sectional view of a benthic substrate according to the presently most preferred embodiment of the invention;

FIG. 10 is a perspective view of an artificial casa that can be created according to a mineral accretion technique; FIG. 11 is a top plan diagram of an example of a lobster ranching operation employing a biomoφhic design for the predator-exclusion barrier and taking advantage of naturally existing shore-line features; and

FIG. 12 is a side cross-section view of an example of an alternative embodiment for a predator-exclusion perimeter for a lobster ranch.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS The following is a description of lobster ranching methods and structures for use in lobster ranching according to the presently most preferred embodiments of the invention.

As used herein, the term "aquaculture" generally refers to the art and science of on-shore cultivation offish, for example, the farming and raising of catfish or salmon in tanks. In the broadest sense, the goal of aquaculture is to eliminate as many complexities and variables as possible from the life-cycle of the fish to produce the highest quantities of healthy adult fish for harvesting as possible with the minimum cost.

Because the biology and life-cycle of the lobster is so complex, rather than attempting to farm lobster in completely artificial, land-based environments that cannot begin to match the complexity of natural environments, the methods of lobster ranching according to the present invention build on natural marine areas that can be artificially enhanced to promote populations of the lobster. Thus, the methods according to the present invention are generally referred to herein as the art and science of "lobster ranching." Spiny lobster are of particular interest for lobster ranching because of the tendency, even willingness of the adult lobster to form large gregarious groups. In contrast, other species of lobster and some crab species are territorial and cannibalistic, which limits their population density and is a negative factor for their selection in a lobster ranching operation. It is to be understood that the same ranching methods of the present invention could be used to increase population densities of other species of lobster and crab. It is anticipated, however, that the use of other species would be less cost effective.

Site Selection According to the invention, selecting a site for the lobster ranching project can be critical to the success of the method and project. According to the most preferred embodiments of the invention, the site for a lobster ranching area is chosen that meets as many as possible of the following criteria.

First, the ranching area should be a marine location that is within a geographical region where the particular species of spiny lobster of interest for ranching are common and preferably thrive.

Second, when enclosed by the predator-exclusion sections, the ranching area should have a natural foraging area already in place for large juvenile and adult foraging. For example, the spiny lobster species Panulirus argus typically utilizes "Turtle Grass" (genus: Thalassia, species: testudinum) and Laurencia algal beds. The selected foraging area specific to the spiny lobster species of choice for the particular lobster ranching area should be well developed before the location of the predator- exclusion sections to enclose the area. Seagrass beds are a scarce resource. To date, the transplanting of seagrass beds has not been successful, but existing seagrass beds can be enhanced. It is anticipated, however, that if the art and science of transplanting seagrass beds develops further, the primary requirement will simply be that the area be suitable for supporting a transplanted seagrass bed or other species-specific foraging bed.

Third, a moderate water movement area for the ranching location is preferred, which insures a clean habitat, sources of nutrients and food, and includes dissolved oxygen.

Fourth, the local currents and/or gyres should preferably provide a natural stream carrying puerulus (postlarval stage) into or near the site so that they may captured for use in the site or naturally settle in the site. These currents can also sweep juveniles into the ranching area through openings or selectively-operable gates in the predator-exclusion perimeter that can be strategically positioned at the ocean floor level. Artificial collection of the postlarval stage lobster where natural currents carry the organism is expected to complement the use of post-larvae collected within the ranching area. Pueruli can be collected periodically when available, employing existing technology and methods.

Fifth, the proposed ranching area should provide natural settlement and/or benthic habitats for juvenile lobster. Nevertheless, some settlement materials can be transplanted using existing techniques. As hereinafter described in more detail, structures formed by mineral accretion methods can provide an excellent substrate for transplanted settlement materials. Settlement and nursery habitats may be provided based on site selection, providing artificial habitats (e.g., small artificial reef habitat holes for spiny lobster species Panulirus japonicus), and/or transplanting of algae and/or seagrass beds. Benthic materials can also be transplanted using existing techniques. In addition, artificial benthic substrates according to the invention are disclosed herein. Predator Exclusion According to the invention, predators of adult lobster or crab are excluded from a marine ranching location. According to an embodiment of the method, a predator- exclusion perimeter is formed to enclose and define a lobster ranching area. The predator-exclusion perimeter serves the following important functions:

(a) it allows natural ocean water to flow into the ranching area through the section to provide clean ocean water carrying minerals, nutrients, and food sources and replenishing dissolved oxygen for the natural faunal and floral assemblage, as well as for the juvenile and adult lobster population within the ranching area;

(b) it allows water to flow out of the ranching area through the perimeter to prevent the build up of waste and biological degradation products in the water; thus, the water within the ranching area has the same complex constituents as the surrounding ocean and remains continuously cleansed; (c) it prevents most of the sharks and finfish predators of juvenile and adult spiny lobster from entering the ranching area through the perimeter, thereby reducing losses due to predation; and

(d) it prevents adult lobster from migrating through the section out of the ranching area. In addition, the predator-exclusion perimeter allows larvae to move with the currents out of the lobster ranching area to live in their natural habitat and feed on plankton. Ideally, the predator-exclusion perimeter should permit postlarval and small juvenile lobster to enter and settle in the ranching area.

The predator-exclusion perimeter preferably encloses and defines the largest ranching area that can be practically protected.

As will hereinafter be described in detail, the ranching area can be partially defined by natural seabed and other barriers, such as existing reef and structures or a shore line. Thus, the ranching area can be advantageously located alongside a coastline or island. The use of existing natural barriers and structures, if available, can reduce the construction costs associated with providing the predator-exclusion perimeter to define a ranching area, provided good current flow is maintained or directed through the ranching area.

The depth of the ranching area enclosed and defined by the predator-exclusion perimeter is preferably shallow, normally having depths in the range of about one (1 ) meter to about fifteen (15) meters (3 feet to about 45 feet), with ideal depths in the range of about one (1) meter to about ten (10) meters (3 feet to about 30 feet). Uniform depth of the ranching area is not required. Depths greater than fifteen (15) meters (45 feet) are possible if the methods are used for other species of lobster, because some species of spiny lobster and crab do well at greater depths. However, all else being equal, greater depths are contraindicated because of the increased construction costs, greater netting requirements, and additional expenses and risks associated with working at such greater depths. At least a portion of the predator-exclusion perimeter has an open-cell structure permits the flow of ocean water and small organisms therethrough, while preventing the entry or egress of larger organisms. For an example of an open-cell perimeter according to another embodiment of the invention, all or portions of the perimeter can be formed of netting. The netting can be simply anchored to the ocean floor buoyantly supported by floats, or it can be more securely supported between piers. Another example of an open-cell perimeter includes stainless steel or monel wire mesh supported between stainless steel posts anchored in concrete foundations. Whether the open-cell structure is formed of netting or wire mesh, it is important that it be adapted to resist saltwater corrosion and occasional severe weather to minimize maintenance costs and breaches in the size-exclusion perimeter. It is expected that an open cell structure including netting for the size-exclusion sections will typically involve the lowest construction costs and provide the best water flow.

Portions of the predator-exclusion perimeter can have a "closed-cell" structure. A closed-cell structure has substantially solid walls, such that it is substantially impervious to water flow. The flow of ocean water and the movement of small organisms into and out of the enclosed ranching area can be controlled through selectively positioned gates, wire-mesh screens, a plurality of relatively small portals, or the like, or any combination of the foregoing. For an example of a closed-cell barrier, according to one embodiment of the invention, all or portions of the predator- exclusion perimeter can be formed with underwater concrete walls. Another, less costly example of an inherently closed-cell structure is a naturally existing reef or shore line.

Except for the shape and placement of the predator-exclusion perimeter, it is constructed according to any suitable techniques. According to a further aspect of the invention, new construction methods and structures are provided for building suitable predator-exclusion sections for a lobster ranch. According to yet another embodiment of the invention, structures for use in the lobster ranching project such as artificial shelters or the predator-exclusion sections can be formed according to mineral accretion methods, such as the methods described in U.S. Patent Nos. 4,246,075; 4,440,605; and/or 4,461 , 684.

Examples of lobster ranches according to the presently most preferred construction methods and structures will hereinafter be described in detail.

Transplanting Seagrass Beds Sea grasses are not currently transplantable at a large scale. Thus, as discussed above, the existence of naturally occurring seagrass beds continues to be critical to site selection. Nevertheless, the invention contemplates that the technology may be developed in the future to permit the transplantation or enhancement of seagrass beds, such as Thalassia testudinum, into the ranching area for providing foraging area for large juvenile and adult lobster.

Removing Lobster Predators After the ranching area is enclosed, lobster predators, primarily large finfish, are removed from the ranching area by any suitable technique, including netting, fish trapping, and/or spear fishing. Removal of the natural predators promotes the survivability of the lobster and increased population densities of the lobster within the ranching area.

Artificial Shelter for Large Juvenile and Adult Lobster

Artificial shelter is preferably provided to provide large-scale artificial shelterfor large juveniles and adult lobster. As used herein, shelterfor "adult" lobster is basically a size-based definition, and does not necessarily mean that the lobster have reached full maturity and reproductive age. Thus, the shelter for adult lobster can also be used by large juveniles.

The artificial shelter can be used to enhance the naturally existing shelter, or to provide shelter where none previously existed. It is expected that providing artificial shelter will greatly increase the ability of an area to support adult lobster populations. Furthermore, positioning artificial shelters outside the predator-exclusion perimeter can be advantageous; promoting lobster habitats in the surrounding marine environment increases the likelihood that juvenile and small adult lobster will enter the ranching area defined by the predator-exclusion perimeter. These casas can be used to help recapture any lobster that may escape from the ranching area.

The artificial shelter is preferably designed to have an overhang, which provides shelter for the lobster during daytime resting.

The casas can preferably be formed of precast elements of sulfate resistant concrete. According to another aspect of the invention, the casas can be formed according to mineral accretion methods, such as the methods described in U.S. Patent Nos. 4,246,075; 4,440,605; and/or 4,461 , 684.

According to another aspect of the invention, the artificial shelters are most preferably arranged in at least one zigzag hedgerow. The zigzag hedgerow provides micro currents and micro environments adjacent to the artificial shelters. In addition, the hedgerows are most preferably arranged to be substantially parallel to the commonly prevailing water current in the ranching area. The substantially parallel arrangement is intended to minimize disruption of the naturally existing macro currents in the area. This reduces the environmental impact of the artificial shelters on natural foraging resources, such as seagrass and algal beds, that are naturally existing within the ranching area. While minimized disruption of the macro currents, however, the zigzag arrangement of the hedgerows enhances the variety of micro currents in the ranching area, as hereinafter described in detail, including venturi effects created across the hedgerow by the different speeds of the micro currents. Thus, the zig-zag arrangement of the artificial shelters gives lobster or crab 360 degrees of choice for venturing into the alcoves defined by the zigzag hedgerows and/or the prevailing macro current, and variations in the micro habitats adjacent to the shelters. While these micro current and venturi effects may be small, they can enhance the habitats for the lobster or crab.

Artificial Benthic Habitats for Later Benthic Phase Juveniles Benthic habitats for the growing later benthic phase juveniles (e.g., greater than about 20 mm in carapace length up to near adult size) are typically architecturally complex rocks and/or corals providing many small holes or crevices with associated algae. Benthic habitats should preferably have a fairly wide range of crevices and hiding spaces for the lobster, which as they grow need to move from one hiding place to a larger hiding place. Such benthic habitats can be naturally occurring or transplanted.

According to a further aspect of the invention, and as will hereinafter be described in more detail, an artificial calcareous cavern matrix has been developed to provide abundant small hiding places and a substrate for algae. Thus, an artificial benthic environment for later benthic phase juveniles can be provided, which promotes the growth of complex natural food sources for these juveniles.

Settlement and Nursery Habitats for Early Benthic Phase Juveniles Settlement and nursery habitats for small eariy benthic phase juveniles (e.g., less than 15 mm in carapace length) are typically architecturally complex structures like the red alga Laurencia. For example, it is possible to transplant drift type

Laurencia, which is readily available, and other types of algae into a tethered buoyant container. Additionally, attached Laurencia can be grown on naturally existing or artificial coral structures, such as the artificial benthic substrate disclosed hereinafter.

It should also be noted that an artificial habitat can be used as a supplement to or to replace Laurencia or other algae. For example, according to a further aspect of the invention, and as will hereinafter be described in more detail, an artificial calcareous cavern matrix has been developed to provide abundant small hiding places and a substrate for algae. The basic difference between such an artificial settlement habitat and the previously mentioned artificial benthic habitat would be that the settlement and nursery habitat would have a generally smaller sized ranged of opening and hiding spaces. Thus, an artificial settlement and nursery environment for early benthic phase juveniles can be provided, which promotes the growth of complex natural food sources for these juveniles.

Vertical Integration

According to one aspect of the invention, the operation is "vertically integrated" to maximize the production capacity within a lobster ranching area.

In particular, the artificial shelterfor the adult lobster provides structural support for benthic habitats. As previously described, benthic habitats for larger, growing benthic phase juveniles (e.g., greater than 20 mm in carapace length) are typically architecturally complex rocks and/or corals providing many small holes or crevices with associated algae. Such benthic habitats can be transplanted or formed on top of the artificial shelters for the adult lobster. An artificial calcareous cavern matrix has also been developed to provide abundant small hiding places and a substrate for algae. Thus, as the lobster continue to mature from eariy benthic phase juveniles to later benthic phase juveniles, they can drop down to the artificial shelterfor the adult lobster. In addition, preferably positioned above the benthic habitats, are settlement and nursery habitats for the small, eariy benthic phase juveniles (e.g., less than 15 mm in carapace length). For example, it is possible to transplant tethered drift type Laurencia as settlement and nursery habitats to float above the artificial shelters and the benthic habitats. As the small eariy benthic phase juveniles mature to larger early benthic phase juveniles, they can drop down from the drift type Laurencia to the benthic habitats.

Thus, the lobster ranching project is preferably vertically integrated, in that the early benthic phase juveniles can first settle in the settlement and nursery habitats, then the growing juveniles can drop down to the benthic habitats below, and finally, the large juveniles can drop down into the artificial shelters below the benthic habitats. Vertical integration can permit up to greater than 85% of the ranching area to be open for seagrass beds and foraging range for adult lobster. Vertical integration can be a key to successful lobster ranching. For example, if the benthic substrates and the settlement and nursery habitats were formed on the ocean floor, rather than being positioned above the casas, the facility would occupy greater than about 45% rather than less than about 15% of the seagrass beds.

In addition, vertical integration allows for gravity feed of the lobster ranching operation from one stage to the next. Gravity feeding means that hand or mechanical transference between the habitats and the attendant damage is avoided or minimized.

Vertical integration functions to help control the direction and rate of flow between habitats for the lobster. As the juvenile lobster grow, they tend to move downward and become ocean floor dwelling. In nature, as lobster transfer from habitat to habitat, they typically do so diagonally, that is, both downwardly and horizontally, because naturally occurring habitats do not typically exist one directly above the next. Horizontal transfer is limited by the ability of the lobster to walk and find the next suitable habitat, ocean currents, and predation on the lobster while they are exposed as they move from one habitat to the next. Vertical integration helps the lobster move from one habitat to the next with minimal losses.

Biomorphic Design for Lobster Ranch According to a further aspect of the invention, sequentially positioned lobster ranching areas can be formed to have a "biomoφhic design." Biomoφhic as used herein describes the step of selecting a shape to work with the biological nature of lobster and natural or modified ocean currents. For example, an initial ranching area can be located up-current of one or more additional ranching areas. A biomoφhic design preferably takes advantage of a natural feature, such as shore-line to form part of the ranching areas of the initial and subsequent links. A biomoφhic design also takes advantage of local current flows. Each link is designed to have up-current openings at the ocean floor level through which juvenile and small adult lobster can enter. Lobster are inclined to migrate or forage in the direction of current flow are thus likely to be funneled from one link to the next. Similarly, juvenile lobster living outside the predator-exclusion perimeter are likely to be funneled with the currents into the ranching area, and so on successively down the row of successive enclosed ranching areas.

Although expected to be less space-efficient than vertical integration, using successively linked ranching areas can be employed in addition to or as an alternative to vertical integration. For example, the first ranching area can be provided with artificial or transplanted settlement and nursery habitats. A second ranching area can provide benthic habitats. A third ranching area can have natural foraging resources for adult lobster, such as seagrass or algal beds. If desired, additional ranching areas can be included in the chain of successively linked ranching areas.

Capturing and Protecting Puerulus Puerulus is a transparent, free-swimming, non-feeding postlarval (PL) stage of the lobster life-cycle. Pueruli very likely have a very low survival rate in the wild.

According to a most preferred embodiment of the invention, the pueruli are captured from the wild and protected in a puerulus moult facility until at least the first instar moult into small, early benthic phase juveniles. Thus, the survival rate of the pueruli can be greatly increased.

The pueruli can be captured at known locations created by ocean currents, which have been mapped by oceanographers. Collection of pueruli can be accomplished using techniques well known to those skilled in the art, such as netting and artificial substrates.

The captured pueruli are held and protected until the first instar moult into small, early benthic phase juveniles. The captured PL stage lobster can be held, for example, in a seine-sized containment net, such as ±2.2 cm stretch with ±0.95 cm openings (±7/8 inch stretch with ±3/8 inch openings).

The small, early benthic juveniles can then be transplanted to the settlement and nusery habitats of the ranching area. By collecting pueruli and restocking them as juveniles at a higher rate and in superior protective habitats in the wild than would naturally occur, it is possible to increase the total number of lobster reaching marketable size and available for harvesting.

If desired, a portion of the early benthic juveniles can be set aside for restocking in the wild outside the protected ranching area for harvesting by fishers outside of the lobster ranching area. Thus, lobster ranching according to the preferred methods of the invention can also increase the total number of lobster surviving in the wild and reaching adult reproductive age. Thus, the lobster ranching operation benefits not only the operator but also the local fishery.

Maintaining the Ranching Area

Continued maintenance of the lobster ranch is helpful for promoting the growth of the product into large juvenile and adult lobster suitable for harvesting.

Maintenance of the lobster ranch includes such activities as repairing or replacing torn netting of the predator-exclusion sections, periodically removing finfish, adding lobster food supplements, and guarding against poaching.

Harvesting Lobster

Harvesting of the lobster (or crab) can be accomplished by conventional techniques known to those of skill in the art, including trapping and hand collecting. Lobster can be harvested any time after they reach marketable size, which is typically considered to be at least 350 g (12 ounces). Because the methods of the present invention contemplate enhancing survivability and statistically enhancing wild populations outside the ranching area, it is not necessary to wait for the lobster to reach adult reproductive age, or to restrict harvesting to one sex, although such practices may further enhance the lobster populations.

Harvested stock can be removed anytime with little damage or loss and can be done in response to standing or specific orders. This permits the harvesting of whole, live lobster on demand. This is in contrast to fishing vessels, which typically remove their catch every three days with an attendant loss and/or damage to the catch.

Lobster Ranch Structures FIGS. 1 and 2 Referring now to the drawings, wherein like reference numerals refer to like parts, FIG. 1 of the drawing is a representative plan view diagram of a lobster ranch, generally referred to by the reference numeral 10, according to the presently most preferred embodiment of the invention.

The lobster ranch 10 is positioned on the floor of an ocean location. The lobster ranch 10 includes a predator-exclusion perimeter 2 for enclosing and defining a ranching area 14 for the adult lobster. Preferably, at least a portion of the enclosed ranching area 14 has naturally-occurring foraging resources for the specific species of lobster or crab desired to be ranched. The foraging resources are typically expected to include naturally existing seagrass and/or algal beds.

As will hereinafter be described in detail, the predator-exclusion perimeter 12 is preferably formed of a plurality of sections 16. According to the presently most preferred embodiment shown in FIG. 1 , each section 16 comprises a suitable predator-exclusion material, such as netting, supported between spaced-apart piers 18. It is to be understood, of course, that two adjacent sections 16 can share a pier 18. Furthermore, the sections 16 need not be identical in length or construction. Thus, a section 16a (representative of any particular section 16), can include, for example, a first pier structure 18a and a second pier structure 18b. A section 16b (representative of a section 16 adjacent to section 16a) can share a pier of the section 16a, such as first pier structure 18a. Similarly, a section 16c (representative of another section 16 adjacent to section 16a on the other side of section 16b) can share a pier structure of the section 16a, such as second pier structure 18b. The representative section 16a of the predator-exclusion perimeter 12 will hereinafter be described in detail with respect to FIGS. 3-6. The design and particular placement of the predator-exclusion perimeter 12 can be important to the commercial success of the methods of lobster ranching. For this reason, the initial cost of building the predator-exclusion perimeter and the costs of maintaining the perimeter in the face of occasional damage from storms or other causes should be minimized. One of the important initial design concerns is to enclose the largest desired ranching area at the most effective cost. For a ranching area selected at least in part for its thriving natural seagrass beds, enclosing the selected ranching area with entirely artificial structures may be necessary.

It is to be understood, however, that the entire perimeter defining the ranching area does not need to provide the function of predator-exclusion, provided that at least a portion of the perimeter permits the flow of water therethrough. In some situations, for example, taking advantage of existing or natural formations, such as reefs or beaches, may be possible to form part of the perimeter defining an enclosed ranching area. All else being equal, where it is necessary to enclose the selected ranching area entirely with artificial structures, a generally circular enclosure is preferred. The circular geometry provides the maximum ranching area enclosure for a running length of the predator-exclusion perimeter. The circular form is also structurally sound. Thus, as shown in FIG. 1 , the predator-exclusion perimeter 12 is preferably in the form of a circle. It is to be understood, however, that the illustrated shape shown in FIG.

1 is representative of any suitable shape for defining a lobster ranching area according to the invention. For example, the underwater surface area is preferably at least about 30,000 square meters, which can be for example, a circular area having a diameter of about 200 meters. Of course, larger or smaller ranching areas can be used.

According to a preferred embodiment of the invention, a plurality of shelters 20 are placed within the ranching area 14 defined by the predator-exclusion perimeter 12. The shelters 20 provide artificial shelter for the lobster as will hereinafter be described in detail. Most preferably, the shelters 20 are vertically integrated as hereinafter described in detail.

According to a preferred embodiment of the invention, the vertically integrated shelters 20 are most preferably arranged in a plurality of zigzag hedgerows 22 as shown in FIGS. 1 and 2. The hedgerows 22 are preferably arranged to be substantially parallel to the commonly prevailing water current in the area, which is graphically represented by arrow 24. The substantially parallel arrangement is intended to minimize disruption of the naturally existing macro currents in the area. This reduces the environmental impact of the vertically integrated shelters 20 on natural foraging resources, such as seagrass and algal beds, that are naturally existing within the ranching area 14.

While minimizing the disruption of the macro currents, the zigzag arrangement of the hedgerows 22 also enhances the variety of micro currents in the ranching area. The micro currents generated about a hedgerow 22a, which is representative of any hedgerow 22, are graphically illustrated in FIG. 2. For example, a micro current 24a of water flowing along one side of a "zig" in the hedgerow 22a tends to speed up relative to the speed of the macro current 24 as the micro current 24a diverges from the general direction of the macro current 24. A micro current 24b flowing along the same side of the following "zag" in the hedgerow 22a tends to slow down again toward the speed of the macro current 24 as the micro current 24b converges toward the general direction of the macro current 24. This provides a variation in current flows, which allows the lobster to find an ideal habitat.

Similarly, continuing to refer to FIG. 2, a micro current 24c of water flowing along the opposite side of a "zag" in the hedgerow 22a tends to speed up relative to the speed of the macro current 24 as the micro current 24c diverges from the general direction of the macro current 24. A micro current 24d flowing along this same side of the following "zig" in the hedgerow 22a tends to slow down again toward the speed of the macro current 24 as the micro current 24d converges toward the general direction of the macro current 24. And a micro current 24e flowing along this same side of the successive "zag" in this hedgerow 22a tends to speed up again relative to the speed of the macro current 24 as the micro current 24e diverges from the general direction of the macro current 24. Thus, multiple micro currents are created, on both sides of the zigzag arrangement of the hedgerow 22a. In addition, a venturi effect is created across the hedgerow by the different speeds of micro currents 24a through 24e. For example, the different speeds of the substantially parallel micro currents 24a and 24d on opposite sizes of a "zig" creating a further micro current represented by arrow 24f across the hedgerow. The faster micro current 24a tends to draw water from the slower micro current 24d across the

"zig" of the hedgerow, helping to provide fresh water supply through the vertically integrated structure. Similarly, the different speeds of the substantially parallel micro currents 24b and 24e on opposite sizes of a "zag" create a further micro current represented by arrow 24g across the hedgerow. The faster micro current 24e tends to draw water from the slower micro current 24b across the "zig" of the hedgerow, helping to provide fresh water supply through the vertically integrated structure.

Thus, the zig-zag arrangement of the shelters gives lobster 360 degrees of choice for venturing into the alcoves defined by the zigzag hedgerows and/or the prevailing macro current 24. While these micro current and venturi effects may be small, they can enhance the habitats for the lobster.

Furthermore, the shelters are preferably interconnected, so that the arrangement of the zigzag hedgerows 22 provide structural support against overturning during storms or when other stochastic forces act on them.

Nevertheless, while the arrangement of the vertically integrated shelters 20 shown in FIGS. 1 and 2 is a presently most preferred arrangement, it is only illustrative, and the vertically integrated shelters 20 can be positioned in other arrangements or randomly within the ranching area 14, according to the constraints of any naturally existing formations.

Continuing to refer to FIG. 1 of the drawing, it is anticipated that an area near the outside of and substantially surrounding the predator-exclusion perimeter 12 can be used as a recapture zone 26. The recapture zone 26 is a substantially unbordered area around the perimeter 12, and includes a reasonable foraging range for any surrounding wild lobster (i.e., distance from the perimeter 12). As will hereinafter be described in detail, some of the wild lobster that may happen to escape from inside the lobster ranch 10 or that may be naturally occurring in the surrounding area near the lobster ranch 10 can be recaptured. Essentially, they can be selectively directed from the recapture zone 26 back into the ranching area 14 by suitable directing structures in the perimeter sections 16. The directing of wild lobster from the recapture zone, through the sections 16 of the perimeter 12, and into the ranching area 14 is graphically represented by arrows 28.

According to the invention, a puerulus moult facility 30 is preferably provided in the lobster ranch 10. According to the presently most preferred embodiment of the invention, the puerulus moult facility 30 is located at or near the middle of the lobster ranch 10. As will hereinafter be described in detail, the puerulus moult facility 30 is a structure for providing shelter to puerulus stage lobster. And as will hereinafter be described in detail, after moulting from the puerulus stage to juveniles, the juveniles are transferred to settlement beds provided in the vertically integrated shelters 20.

FIGS. 3-6 Referring now to FIG. 3, a representative section 16a, including its representative first pier structure 18a and second pier structure 18b, of the predator- exclusion perimeter is shown in detail. It is also to be understood, that the first pier structure 18a and the second pier structure 18b are shown to illustrate that the adjacent sections 16b and 16c, respectively, can form a straight portion of the predator-exclusion perimeter or a convenient angle in a portion of the predator- exclusion perimeter.

According to the invention, the first pier structure 18a preferably includes a spread footing 32a. The spread footing 32a is positioned at the ocean floor, indicated by line 33 (FIGS. 4 and 5), to provide structural support for a vertical pier 34a. The spread footing 32a can be, for example, overall about 20 - 25 cm (8 - 10 inches) thick. As shown in the FIGS. 3-6 of the drawing, the vertical pier 34a is most preferably in the form of a circular post. The vertical pier 34a is preferably formed of a composite, such as a vertically positioned steal wide flange ("WF") column 36a encased in concrete 38a. The first pier structure 18a is most preferably prefabricated off-site to minimize construction costs of the predator-exclusion perimeter.

As shown in FIG. 4, a lower portion 40a of the WF-column 36a extends below the spread footing 32a. This lower portion 40a is driven downward into the ocean floor to anchor the first pier structure 18a. This system can eliminate drilling, which may cause debris to be spewed into the seagrass beds causing environmental damage, and minimizes labor costs and on-site poured concrete construction. The pile system is ideal for limestone formations, but is also suited to soil based formations. Other formations may require alternative building techniques.

An upper portion 42a of the vertical pier 34a extends upward from the spread footing 32a, and most preferably above the surface of the ocean at high tide, indicated by line 43. Referring back to FIG. 3, the second pier structure 18b is preferably constructed to be substantially the same as the first pier structure 18a. Thus, the second pier structure 18b preferably includes a spread footing 32b. The spread footing 32b is positioned at the ocean floor, indicated by line 33 (FIGS. 4 and 5), to provide structural support for a vertical pier 34b. The spread footing 32b can be, for example, overall about 20 - 25 cm (8 - 10 inches) thick. As shown in FIG. 3 of the drawing, the vertical pier 34b is most preferably in the form of a circular post. The vertical pier 34b is preferably formed of a composite, such as a vertically positioned steal WF-column 36b encased in concrete 38b. The second pier structure 18b is most preferably prefabricated off-site to minimize construction costs of the predator- exclusion perimeter.

According to the presently most preferred embodiment of the invention, optionally positioned between two adjacent pier structures, such as pier structures 18a and 18b shown in FIGS. 3-6 of the drawing, are one or more casas, represented by first casas 44a. First casa 44a is designed to provide ocean-floor level shelter for large juvenile and adult lobster. The lobster can congregate under the casa 44a and feel secure from predators. It is believed that ensuring that plenty of den space is available for the juvenile and adult lobster is important so that they all have a place where they can aggregate and feel safe from predation, even if otherwise substantially protected by the predator-exclusion perimeter; the feeling of safety during the day is expected to reduce the stress on the lobster and the likelihood that they might feel the urge to migrate from the ranching area.

The casa 44a shown in FIGS. 3-6 can be made, for example, from wire mesh or concrete. The casa 44a preferably has a low profile. Most preferably, the first casa 44a is formed of precast concrete. As will hereinafter be described, the casa 44a can alternatively be formed using mineral accretion techniques. The casa 44a is illustrated as being rectangular, but it can be of any convenient design and shape. The casa 44a can be, for example, approximately 18 meters (60 feet) long and 3 meters (10 feet) wide. It is to be understood, however, that the particular design and size of the cases is not important, so long as they provide suitable shelter for adult lobster.

In the presently most preferred embodiment of the invention, the first casa 44a preferably has first support leg 46a and second support leg 48a, which support a substantially horizontal top 50a. According to the presently most preferred embodiment of the invention, the support legs 46a and 48a are substantially parallel along the length of the casa 44a as shown in the drawing to simplify design and minimize construction costs. The top 50a extends outward from the support legs 46a and 48a to form overhangs under which large juvenile and adult lobster can seek shelter and aggregate.

As shown in FIGS.3-6 of the drawing, the support legs 46a and 48a of the first casa 44a are preferably positioned on the spread footing 32a of the first pier structure 18a and on the footing 32b of the second pier structure 32b. The casa 44a is also preferably positioned on the spread footing 32a to be elevated above the ocean floor, most preferably about 8 cm (3 inch) from the ocean floor 33. Thus, an elongated opening 52a is defined by the bottom of the support leg 46a of the first casa 44a and the ocean floor 33 and between the spread footings 32a and 32b. Similarly, there is a corresponding elongated opening 53a beneath the support leg 48a and the ocean floor 33. As will hereinafter be explained in detail, at least one of these elongated openings 52a and 53a should be normally blocked to prevent the escape of lobster therethrough from the lobster ranch. Furthermore, as will hereinafter be explained in detail, these openings 52a and 53a beneath the casa 44a used at the predator- exclusion perimeter can be used for recapturing adult and large juvenile lobster that may have escaped from within the lobster ranch. As shown in FIG. 3 of the drawing, the end of a second casa 44b is positioned adjacent the first pier structure 18a, and the end of a third casa 44c is positioned adjacent the second pier structure 18b. The second and third casas 44b and 44c, respectively, are preferably of substantially the same design and preferably formed of precast concrete as described for the first casa 44a, which minimizes construction costs for the lobster ranch.

A suitable means for connecting adjacent casas to each pier structure 18 is preferably provided, which can help anchor the casas in position and can help stabilize and strengthen the pier structures 18. According to the presently most preferred embodiment of the invention, for example, the adjacent casas are connected to the pier structures 18 by means of a plurality of tension members connected therebetween.

FIGS. 3 and 4 of the drawing show a particular connecting means 56a for connecting the adjacent first and second casas 44a and 44b, respectively, to the spread footing 32a of the pier structure 18a. The connecting means 56a includes four tension members 58a, 60a, 62a, and 64a. An outer footing anchor 66a is attached to the spread footing 32a of the first pier structure 18a toward the outside of the lobster ranch and an inner footing anchor 68a is attached to the spread footing 32a toward the inside of the lobster ranch. Four casa anchors 70a, 72a, 74a, and 76a are also included, which are connected toward the corners of two adjacent casas 44a and 44b, respectively. In particular, the first casa anchor 70a is connected toward the outer corner of the adjacent first casa 44a, the second casa anchor 72a is connected toward the inner corner of the adjacent first casa 44a, the third casa anchor 74a is connected toward the inner corner of the adjacent second casa 44b, and the fourth casa anchor 76a is connected toward the outer corner of the adjacent second casa 44b. As shown in the drawings, the four tension members 58a, 60a, 62a, and 64a are preferably arranged in substantial opposition to each other in a substantially quadrilateral geometry. Each of the tension members preferably has conventional threaded connector for easily adjusting the length of the tension member and tightening the tension member between the anchors. Each of the footing anchors 66a and 68a and each of the four casa anchors 70a, 72a, 74a, and 76a preferably permits a flexible orientation of the tension member connected thereto. Thus, the geometry can be suitably adjusted for the desired angle between sections 16a and 16b. Similarly, FIGS. 3 and 5 of the drawing show a particular connecting means

56b for connecting the adjacent casas 44a and 44c to the spread footing 32b of the pier structure 18b. The connecting means 56b includes four tension members 58b, 60b, 62b, and 64b. An outer footing anchor 66b is attached to the footing 32b of the pier structure 18b toward the outside of the lobster ranch and an inner footing anchor 68b is attached to the footing 32b toward the inside of the lobster ranch. Four casa anchors 70b, 72b, 74b, and 76b are also included, which are connected toward the corners of two adjacent casa 44b and 44c. In particular, the first casa anchor 70b is connected toward the outer comer of the adjacent second casa 44c, the second casa anchor 72b is connected toward the inner comer of the adjacent second casa 44c, the third casa anchor 74b is connected toward the inner comer of the adjacent first casa 44a, and the fourth casa anchor 76b is connected toward the outer comer of the adjacent first casa 44a. As shown in the drawings, the four tension members 58b, 60b, 62b, and 64b are preferably arranged in substantial opposition to each other in a substantially quadrilateral geometry. Each of the tension members preferably has conventional threaded connector for easily adjusting the length of the tension member and tightening the tension member between the anchors. Each of the footing anchors 66b and 68b and each of the four casa anchors 70b, 72b, 74b, and 76b preferably permits a flexible orientation of the tension member connected thereto. Thus, the geometry can be suitably adjusted for the desired angle between adjacent sections 16a and 16c.

The geometry of the connecting means 56a and 56b provides a means for interlocking the pier structures 18a and 18b with the casa therebetween, represented by the first casa 44a. (If more than one casa is positioned between the pier structures

18a and 18b, for example, intermediate footings, without columns, can be used to support the casas on the sea floor.) The connecting means 56a and 56b also provides a means for connecting that can be easily adjusted regardless of the angle between adjacent sections, such as sections 16a, 16b, and 16c. These structural elements can be combined in series, such as sections 16a, 16b, and 16c, to form an interlocking structure for the perimeter that is relatively strong for withstanding the ocean forces yet relatively inexpensive to construct.

According to the invention, the predator-exclusion material is preferably in the form of a netting 78a (FIG. 4), which is most preferably formed of a high-strength polyethylene polymer that has excellent ultra-violet light, abrasion, and chemical resistance. The size can be, for example, 4.5 cm (1.75 inch) stretch as used for shrimping. This size will exclude predators and contain the large juvenile and adult lobster while allowing maximum flow of water through the ranching area. One such netting material is available from Allied Signal Coφoration under the name "SPECTRA."

Predator-exclusion netting 78a for the section 16a is mounted between pier structures 18a and 18b shown in FIGS. 3-6 of the drawing. As best shown in FIGS. 3, 4, and 6 of the drawing, a pier float 80a is shown connected to the vertical pier 34a. The pier float 80a is preferably in the form of a floatation ring that is captured on the vertical pier 34a. The pier float 80a rises and falls on the vertical pier 34a with tide. The netting 78a is similarly connected to the other pier structure 18b. In addition, one or more head rope floats 82a can be attached to the head rope of the netting 78a to help maintain the netting at the ocean surface. Thus, the netting 78a can be maintained substantially at the ocean surface despite changes in tide, and can at least partially respond to swells. If desired or needed, weights (not shown) can be attached to the foot rope of the netting to help maintain the netting between the ocean surface 43 and the ocean floor 33. For example, the foot rope of the netting 78a can be weighted to rest along the top of the casa 44a and the footing 32a of predator- exclusion section 16a. Thereby, the opportunity for finfish to pass over or under the net into the ranching area is minimized. Other portions of predator exclusion netting can be similarly connected to the other pier structures 18. In the alternative, the netting can be held on the pier above high tide level, thereby eliminating the need for pier floats 80a and 82a.

As will hereinafter be described in more detail, any available surfaces of the section 16a of the predator-exclusion perimeter can have transplanted thereon suitable settlement and nursery habitats, such as algae, for small, eariy benthic phase juveniles. The selected settlement and nursery habitats are species specific, for example, red algae for the spiny lobster species Panulirus argus.

Referring to FIGS. 3-6 of the drawing, according to the presently most preferred embodiment of the invention, the casas, such as casa 44a, are provided with a benthic substrate 84a on the top 50a thereof. The presently most preferred benthic substrate will hereinafter be described in detail with reference to FIG.9. Most preferably, additional benthic substrate 86a is positioned vertically at the ends of the casa 44a to close the space between the support lets 46a and 48a against the intrusion of predator finfish. The benthic substrate can be formed of an artificial material as hereinafter described in detail. The benthic substrate provides complex shelter structures for benthic phase lobster and small juveniles. The benthic substrate is also provides a good substrate for algae 88a, which is an important foraging area for the growing benthic phase juvenile lobster.

Furthermore, according to vertical integration, settlement and nursery habitats are preferably positioned above casa 44a. According to the presently most preferred embodiment of the invention, a tethered prismatic volume (TPV) 90a is attached to the casa 44a (FIGS. 4 and 6). A tethered prismatic volume is a netting structure that is adapted to buoyantly float above the casa 44a. The netting of the TPV is most preferably arranged into the shape of an enclosed prism. While other enclosed shapes can be useful, the advantage of the prism is that except when the sun is directly overhead, for most orientations of the TPV, sunlight to the areas below the TPVs is less obstructed. Two or more buoyant compression members 92a are attached to the ends of the netting of the TPV to accomplish two puφoses: (1) to make sure the TPV tends to float upward in the ocean water; and (2) to hold the shape of the netting into an enclosed prism as shown in the drawings. The TPV netting can be large scale netting, for example, having 20 cm stretch and 10 cm openings (8 inch stretch and 4 inch openings), to contain the algae and exclude birds. The TPV has at least one line, and preferably two or more lines 94a for anchoring the TPV. The lines 94a can be tied, for example, to attachment holes 95a (shown in FIGS. 3, 5 and 6) formed in the top 50a of casa 44a. The TPV is preferably anchored such that the netting of the TPV preferably floats at or near the ocean surface 43. Most preferably the TPV is tethered to float about one meter (3 feet) beneath the ocean surface 43, which helps protect the small eariy benthic phase juveniles living in the TPV 90a from the birds. The lines 94a also help maintain the longitudinal shape of the TPV netting. Suitable algae 96a is transplanted to grow in the tethered prismatic volume 90a. The algae 96a provides additional settlement and foraging area for the small eariy benthic phase lobster. In addition or in the alternative, artificial nursery materials can be provided for use in the TPV.

When anchored to the casas, the tethered prismatic volumes illustrate the principle of vertical integration of the lobster ranching method according to the invention. Small early benthic phase lobster can settle or be transplanted on the algae 96a of the TPV 90a. As the juveniles grow larger, they drop down from the algae 96a of the TPV 90a onto the benthic substrate 84a and 86a of the casa 44a. As the benthic and small juveniles continue to mature into larger juvenile and adult lobster, they can drop down to live under the casa 44a. When the lobster reach marketable size they can be harvested from the casa 44a or collected by using placing conventional lobster traps in the lobster ranching area.

Referring now particularly to FIG. 6 of the drawing, the casa 44a is preferably provided with a selectively operable gate mechanism for recapturing lobster from the surrounding recapture zone of the lobster ranch. According to the presently most preferred embodiment of the invention, the gate mechanism includes one or more sections of inside pipe 100a and one or more sections of outside pipe 102a. The pipes 100a and 102a are preferably formed of plastic, such as polyvinyl chloride

(PVC) pipe. The inside pipe 100a is formed or cut to a length that is substantially equal to the length of the casa 44a, and more particularly, sufficient to block the length of the elongated opening 52a beneath the leg 46a along side of the casa 44a. Similarly, the outside pipe 102a is formed or cut to a length that is substantially equal to the length of the casa 44a, and more particularly, sufficient to block the length of the elongated opening 53a along the side of the casa 44a. The inside pipe 100a can be manually moved into a position alongside the leg 46a to block the opening 52a beneath the leg 46a of the casa 44a, or the pipe 100a can be manually moved away from the casa to open the opening 52a beneath the leg 46a of the casa 44a. Similarly, the outside pipe 102a can be manually moved into a position alongside the leg 48a to block the opening 53a beneath the leg 48a of the casa 44a, or the pipe 102a can be manually moved away from the casa to open the opening 53a beneath the leg 48a of the casa 44a. If desired, closures that are automatically or remotely operated can be used for selectively operating one or more of the gate mechanisms. Accordingly, when the outside pipe 102a is moved out of the way to open the opening 53a beneath leg 48a, lobster from outside the lobster ranch may use the protection of the casa 44a, but because the inside pipe 100a is closed or blocked, the lobster from within the lobster ranch cannot escape. During the daytime, when the lobster are resting in the inner shelter area 54a, the outer pipe 102a is moved to the closed position to block the opening 53a, and the inside pipe 100a is then moved to open the opening 52a. Thus, when nightfall comes the lobster leave the shelter of the casa 44a through opening 52a and are directed into the foraging areas of the enclosed lobster ranch. Then, preferably during the nighttime foraging when the casa 44a is substantially unoccupied by lobster, the inside pipe 100a is moved back into the position alongside the casa 44a to block the opening 52a, and the outside pipe

102a is moved to unblock the opening 53a. Because the inside pipe 100a is closed, few or none of the lobster from within the lobster ranch can enter the inner shelter area 54a of the casa 44a. Thus, the recaptured lobster that have been directed into the lobster ranch find new dens inside the protected lobster ranch. Meanwhile, additional escaped lobster from the recapture zone are able to find a home in the casa 44a, and the recapturing process is repeated. Thus, lobster can be selectively directed from a recapture zone through the casa 44a of a section 16a into the lobster ranch.

FIG. 7 Turning now to FIG.7 of the drawing, a cross-section of a representative fourth casa 44d forming part of a hedgerow within the lobster ranch is shown. The casa 44d is most preferably of substantially the same design and construction as the first casa

44a previously described for use in the perimeter section 16a, with the notable exceptions that no pier or predator exclusion netting is required.

In particular, the fourth casa 44d, is similarly designed to provide substantially ocean floor level shelterfor adult lobster. The adult lobster can congregate under the fourth casa 44d, and others like it, and feel secure from predators. It is believed that ensuring that plenty of den space is available for the juvenile and adult lobster is important so that they all have a place to retire where they can feel safe from predation, even if otherwise substantially protected by the predator-exclusion perimeter; the feeling of safety during the day is expected to reduce the stress on the lobster.

The casa 44d shown in FIG. 7 can be made, for example, from woven wire mesh or concrete and preferably have a low profile. Most preferably, the fourth casa 44d is formed of precast concrete. The casa 44d is illustrated as being rectangular, but it can be of any convenient design and shape. The casa 44d can be, for example, approximately 18 meters (60 feet) long and 3 meters (10 feet) wide. It is to be understood, however, that the particular design and size of the cases is not important, so long as they provide suitable shelter for adult lobster.

In the presently most preferred embodiment of the invention, the fourth casa 44d preferably has first and second support legs 46d and 48d, respectively, which support a substantially horizontal top 50d. According to the presently most preferred embodiment of the invention, the support legs 46d and 48d are substantially parallel as shown in the drawing to simplify design and minimize construction costs. The top 50d extends outward from the support legs 46d and 48d to form overhangs under which adult lobster can seek shelter and congregate.

As shown in FIG. 7 of the drawing, the support legs 46d and 48d of the casa 44d can optionally be positioned on spread footings 104d. The casa 44d can be substantially elevated above the ocean floor, most preferably about 8 cm (3 inch). Thus, small, elongated openings 52d and 53d, respectively, are defined by the bottom of the support legs 46d and 48d of the fourth casa 44d and between the end footings 104a. Adult lobster can walk through these elongated opening 52d and 53d to reach an inner shelter area 54d of the casa 44d between the support lets 46d and 48d to be substantially protected from predators. The fourth casa 44d is preferably of substantially the same design and preferably formed of precast concrete as described for the first casa 44a, which minimizes construction costs for the lobster ranch.

As will hereinafter be described in more detail, any available surfaces of the fourth casa 44d preferably have transplanted thereon suitable settlement and nursery habitats, such as algae, for eariy benthic phase juveniles. The selected settlement resources are species specific, for example, red algae for the spiny lobster species Panulirus argus.

Continuing to refer to FIG. 7 of the drawing, according to the presently most preferred embodiment of the invention, the casas, such as casa 44d, are provided benthic substrate 84d on the top 50d thereof. Most preferably, additional benthic substrate 86d is positioned vertically at the ends of the casa 44d, thereby the space between the support lets 46d and 48d against the intrusion of predator finfish. The benthic substrate can be formed of an artificial material as hereinafter described in detail. The benthic substrate provides complex shelter structures for the growing benthic phase juveniles. The benthic substrate is also provides a good substrate for algae 88d, which is an important foraging area for the growing benthic phase juvenile lobster.

Furthermore, according to the presently most preferred embodiment of the invention, a tethered prismatic volume (TPV) 90d is attached to the casa 44d. A tethered prismatic volume is a netting structure that is adapted to float above the casa

44d. The netting of the TPV is most preferably arranged into the shape of an enclosed prism. Two or more buoyant compression members 92d are attached to the ends of the netting of the TPV to accomplish two puφoses: (1) to make sure the TPV tends to float upward in the ocean water; and (2) to help hold the shape of the netting into an enclosed prism as shown in the drawings. The TPV includes two or more lines 94d for attaching the TPV to the casa 44d such that the netting of the TPV floats at or preferably beneath the ocean surface 43. The lines 94d also help maintain the longitudinal shape of the TPV netting. Suitable algae 96d is transplanted to grow in the tethered prismatic volume 90d. The algae 96d provides additional settlement and foraging area for the small eariy benthic phase lobster.

The tethered prismatic volumes illustrate the principle of vertical integration of the lobster ranching method according to the invention. The small early benthic phase lobster can settle or be transplanted on the algae 96d of the TPV 90d. As they grow, they drop down from the algae 96a of the TPV 90d onto the benthic substrate 84d of the casa 44d (or onto the benthic substrates of nearby casas). As the benthic and small juveniles continue to mature into larger juvenile and adult lobster, they can drop down to live under the casa 44a. When the lobster reach marketable size, they can be harvested from the casa 44d or by using conventional lobster traps placed within the lobster ranching area.

In addition, the tethered prismatic volumes are part of the vertically integrated shelters. The TPVs aid in reinforcing the micro currents of water movement within the ranching area.

FIG. 8 Referring now to FIG.8 of the drawing, a presently most preferred embodiment for a puerulus, post larval moult facility 30 is shown in detail. To minimize construction costs, the sides of the PL moult facility 30 preferably have a similar structure as the previously described perimeter section 16a.

The PL moult facility 30 is most preferably in the form of a square, having four comer pier structures, such as the two pier structures 18c and 18d shown in FIG. 8. The pier structures 18c and 18d are similar in construction to the previously described pier structures 18a and 18b. Thus, the pier structure 18c preferably includes a spread footing 32c. The spread footing 32c is positioned at the ocean floor, indicated by line

33, to provide structural support for a vertical pier 34c. As shown in FIG. 8 of the drawing, the vertical pier 34c is most preferably in the form of a circular post The vertical pier 34c is preferably formed of a composite, such as a vertically positioned steal WF-column encased in concrete as previously described. The fourth pier structure 18d shown in FIG. 8 is also preferably constructed to be substantially the same as the other, previously described pier structures 18a, 18b, and 18c.

A portion of the puerulus containment netting 106 for the PL moult facility 30 is mounted between pier structures 18c and 18d shown in FIG. 9 of the drawing. The captured PLs can be held, for example, in a seine-sized containment net, such as such as (±2.2 cm stretch with ±0.95 cm openings (±7/8 inch stretch with ±3/8 inch openings).

Pier floats 80c and 80d are shown connected to the vertical pier 34c and 34d, respectively. Each of the pier floats 80c and 80d is preferably in the form of a floatation ring that is captured on the vertical piers 34c and 34d, respectively. The pier floats 80c and 80d rise and fall on the vertical piers 34c and 34d with tide. The PL containment netting 104 is connected to the pier floats 80c and 80d. In addition, one or more head rope floats 82c can be attached to the head rope of the containment netting 106 to help maintain the netting at the ocean surface 43. Thus, the containment netting 106 can be maintained substantially at the ocean surface despite changes in tide, and can at least partially respond to swells. If desired or needed, weights (not shown) can be attached to the foot rope of the netting to help maintain the netting suspended from the ocean surface 43 to the ocean floor 33. In addition, a cover netting 107 is most preferably provided to protect the PLs in the PL moult facility 30 from birds. Thereby, the predation of the PLs in the facility 30 is minimized.

Other portions of PL containment netting 106 can be similarly connected to the other pier structures 18 of the PL moult facility 30. In the alternative, the netting 106 and cover netting 107 can be held on the pier above high tide level, thereby eliminating the need for floats 80c and 80d and 82c.

The moult facility 30 is preferably divided into an upper area 108 and a lower area 110. The upper area 108 is for the transfer of recently captured PLs. It is preferably filled with Laurencia or other algae and or artificial substrates. The environment is intended to mimic natural PL settlement habitats in the wild. By placing the captured PLs in the upper area 108, they have no option but to moult in the moult facility 30 of the lobster ranch.

The juveniles have a tendency to become ground dwelling, albeit in natural environments. After moulting, they will settle to the lower level 110 of the moult facility 30. These eariy benthic phase juveniles may be transferred immediately to other settlement and nursery habitats of the lobster ranch or allowed to moult several more times so that they become larger and more hardy for the transfer and more successful in avoiding any predation.

The moult facility 30 is also preferably provided with an inclined bottom 112 that directs the early benthic phase juveniles as they grow larger toward a small shelter 114, and into a collection container 116.

FIG. 9

Referring now to FIG.9 of the drawing, a presently most preferred embodiment of an artificial calcareous cavern matrix 120 is shown in more detail. Depending on the range in the sizes of the matrix openings, the matrix 120 can be used for either a benthic substrate 84a or 84d and/or for a settlement and nursery habitat. According to an aspect of the invention, the matrix 120 includes a structural material 122 that is formed to provide appropriately-sized recesses and openings 124 for later benthic phase juveniles. According to another aspect of the invention, the matrix 120 includes a structural material 122 that is formed to provide appropriately- sized recesses and openings for early benthic phase juvenile lobster. One example of a suitable material for the structural material 122 is polyamide six (commonly known as Nylon Six). Another example is high density polyethylene. Other synthetic materials can be used. Nylon Six has properties that allow adhesion of coatings that enhance the ability of the substrate to attract and grow flora and fauna. The structural material 122 is preferably in the form of a non-woven material, as opposed to woven materials. A non-woven structure provides increased variation in opening sizes. The variations provide choices for both lobster and other flora and fauna in the artificial benthic environment. Non-woven materials also tend to have more acute angles therein, which are attractive to some organisms as points of attachment, e.g., for wedging into the crevices and which improves the strength of the attachment. However, it is expected that both non-woven or woven materials will work for the intended puφose.

The structural material 122 can have any practical dimensions. The most important dimension is the thickness, which should be at least about 1 cm (1/2 inch) for defining recesses of at least such size therein. The typical thickness is expected to be in the range of about 5 cm (2 inch) to about 15 cm (6 inch). For example, the structural material can be about 8 cm thick and 3 meters by 18 meters (3 inch thick and 10 feet by 60 feet).

The structural material 122 has voids and recesses 124 formed therein to provide hiding places and protection for juvenile lobster. The voids may vary from 10% to about 90% of the volume, limited only by the structural capability of the structural material. For example, if the structural material is formed of non-woven Nylon Six, the structural material can have voids and recesses totaling approximately

70% of the volume.

Calcium caΦonate (CaC0₃) is the chemical basis of naturally occurring coral. Many types of marine flora and fauna adhere to, grow on, and live in and around coral. Accordingly, the artificial calcareous cavern matrix 120 has a surface material that either initially has formed thereon, or when put in the ocean will form, a calcium carbonate based surface that enhances the ability of the substrate to attract and grow flora and fauna.

It is known that a cementitious material, such as Portland cement, when placed in water will gradually form a calcareous surface layer. Portland cement mostly consists of combined calcium silicates. When these calcium silicates react with water, or hydrate, calcium hydroxide [Ca(OH)J is formed along with a complex mixture of other materials (usually called calcium silicate hydrate gel), which hardens to cement. The calcium hydroxide in the surface of the cement can react with carbonic acid [H2C0₃J, which is normally present in water, to form calcium carbonate [CaC0₃], according to the following chemical equation:

Ca(OH)₂ + H₂C03 < — > CaC0₃ + H₂0

This process is known as carbonation, and the equilibrium is shifted heavily in favor of calcium carbonate production (i.e., under normal conditions, very little of the calcium carbonate reacts back to calcium hydroxide.)

Thus, according to the presently most preferred embodiment, a cementitious coating 126 is applied to the structural material 122. A latex calcareous coating that is also flexible is more preferred. For example, the coating of choice is commercially available from Sonnebom's "FLEXTIGHT", which is a cementitious wateφroofing membrane, manufactured by ChemRex, Incoφorated of Shakopee, Minnesota, U.S.A. But any coating that has a cementitious based finish will react in water to form a calcium carbonate based finish.

In the alternative, it is expected that a calcareous surface finish can be formed directly on the structural material 122. For example, it is expected that mineral acretion techniques as hereinafter described can be used to form a calcareous surface on a structural material 122. The matrix 120 provides a highly complex structure having a suitable calcareous surface 126. Algae and other flora can readily attach to the calcareous coating 126.

Alternative "Mineral Accretion" Building Technigues

FIG. 10 U.S. Patent No. 4,246,075 entitled "Mineral Accretion of Large Surface Structures, Buildings Components and Elements" issued January 20, 1981 to Wolf W. Hilbertz discloses a method of creating artificial structures in the sea. By establishing a direct electrical current between electrodes in an electrolyte like seawater, calcium carbonates, magnesium hydroxides, and hydrogen are precipitated at the cathode, while oxygen and chlorine are produced at the anode. The electrodeposition of minerals is utilized to construct large surface area structures of a hard, strong material, for example, having between 1,000 and 8,000 pounds per square inch compression strength. To make a large surface area structure of a hard, strong material, a pre-shaped form of electrically conductive material is disposed in a volume of electrolyte, such as seawater, to serve as a cathode, one or more anodes are disposed in proximity to the form, and a direct electrical current is established between the electrodes for a period of time sufficient to accrete a solid covering of precipitated material onto the form. The entire specification of U.S. Patent No.

4,246,075 is hereby incoφorated by reference.

U.S. Patent No.4,440,605 entitled "Repair of Reinforced Concrete Structures by Mineral Accretion" issued April 3, 1984 to Wolf W. Hilbertz discloses a method of repairing reinforced concrete structures. To repair reinforced concrete structures, the structure is disposed in a volume of electrolyte. The metal reinforcement is made a cathode by connection to the negative terminal of a suitable direct current power supply. One or more anodes are disposed in proximity to the structure, and a direct electrical current is established between the electrodes for a period of time sufficient to fill by accretion cracks, fissures, or voids in the concrete body of the structure. The entire specification of U.S. Patent No.4,440,605 is hereby incoφorated by reference. U.S. Patent No. 4,461,684 entitled "Accretion Coating and Mineralization of Materials for Protection Against Biodegradation" issued July 24, 1984 to Wolf W. Hilbertz discloses a method of protecting fibrous materials, such as wood or cables.

To provide a mineral coating on a structure made of a fibrous material, one or more cathodes are inserted in the structure, which is disposed in an electrolyte such as seawater, brine, or brackish water. One or more anodes are disposed in proximity to the structure, and a direct electrical current is established between the electrodes for a period of time sufficient to coat the structure and/or mineralize the fibrous material.

The entire specification of U.S. Patent No. 4,461 ,684 is hereby incoφorated by reference.

The mineral accretion method of marine construction is relatively inexpensive, and it provides an excellent substrate as an artificial reef for the growth of reef flora and fauna. For example, the surfaces of structures formed by mineral accretion methods provide excellent substrates for the transplantation of red algae species Laurencia for providing a settlement and nursery habitat for spiny lobster of the species Panulirus argus, or algal clumps located near reef holes for providing a settlement and nursery habitat for spiny lobster of the species Panulirus japonicus. The predator-exclusion perimeter represented in FIG. 1 of the drawing can alternatively be formed, for example, of the structural pier 18 that supports a woven wire mesh of a suitable mesh size, for example, less than about two (2) inches. The maximum size of the openings is selected to limit or prevent the entry of predatory sharks and finfish while retaining adult lobster within the ranching area. The predator- exclusion perimeter preferably extends from the ocean floor up to about the high tide sea level. The predator-exclusion perimeter permits the flow of surrounding ocean water through the enclosed area, but keeps predators out and adult lobster in.

Some of the openings in the mesh can be adjacent the ocean floor such that juvenile and small lobster can simply walk through a mesh opening into the ranching area, but once they grow to adult they should be substantially retained within the ranching area. At least some of these openings in the predator-exclusion perimeter are most preferably positioned so that lobster moving in the general direction of the surrounding ocean current are likely to enter the ranching area, since lobster tend to move or migrate with ocean currents, not against them. For similar reasons, the down-current openings in predator-exclusion perimeter are preferably spaced above the ocean floor, to help prevent lobster from simply walking out of the ranching area. According to one embodiment of the invention, the woven wire mesh is formed of stainless steel to resist corrosion from saltwater. Other metals and alloys can be used for the structural elements of the predator-exclusion perimeter, particularly those highly resistant to saltwater corrosion, such as brass or copper; however, it is anticipated that these other metals may be too expensive.

According to this alternative embodiment of the invention, the woven wire mesh is covered with mineral accretion according to the techniques disclosed in U.S.

Patent Nos.4,246,075; 4,440,605; and/or 4,461 ,684. The mineral accretion protects the metal framework, allowing use of less expensive structural metals for building the predator-exclusion perimeter. The calcium carbonate material of the mineral accretion also provides an excellent artificial substrate for reef life, which can become an important food and shelter resource for the lobster.

According to a still further aspect of the present invention, improvements in the mineral accretion techniques are provided. One modification is to provide a conducting mesh material formed of non-metallic conducting material, such as graphite or a graphite composite material. These types of non-metallic materials are strong, extremely resistant to saltwater corrosion, relatively inexpensive, and can provide a good substrate for the mineral accretion process.

Referring to FIG. 10 of the drawing, an artificial shelter 130 is shown as it can be formed according to mineral accretion techniques. Shelter 130 can include a frame 132 formed of a conducting non-woven matrix similar to the structural matrix 122 shown in FIG. 9. The frame 132 can define any suitable lobster shelter design, such as the casa design illustrated in FIG. 10, which is generally box-like and has an narrow opening 134 of about 8 cm (3 inches) high for adult lobster to enter under the shelter 130. The shelter 130 can be designed to have a vaulted or domed top 136, which optimizes the compressive characteristics of calcium carbonate materials.

The frame 132 has anchors 138, which can also serve as electrical connectors for providing voltage and current across the conducting non-woven matrix of frame 132. According to the mineral accretion technique, applying a direct current voltage across the conducting non-woven matrix of the 132 causes minerals from the surrounding seawater to precipitate out onto the wire mesh frame 132, building up a calcium carbonate based covering 140.

In the alternative, the frame 132 need not be formed of wire mesh, but could be formed of any other suitable structural material and can be coated with a calcareous coating as previously described herein.

Example of Biomorphic Design for Lobster Ranch FIG. 11 FIG. 11 of the drawing illustrates an alternative design for a lobster ranch employing an example of a biomoφhic design. In particular, the illustrated biomoφhic design includes one or more predator-exclusion perimeters, such as 212a, 212b, 212c, and 212d, defining one or more ranching areas, such as 214a, 214b, 214c, 214d. The predator-exclusion perimeters 212a-d are preferably at least partially defined include naturally existing shore-line features, such as shoreline 215. In addition, a portion of the predator-exclusion perimeters 112a-d can be formed of a plurality of predator-exclusion sections, such as those previously described herein, which have plenty of appropriately sized openings to permit substantial current flow 224 through the ranching areas 212a-d.

The initial ranching area 214a can be located up-current of one or more additional ranching areas 214b-d. Each link is designed to have up-current openings at the ocean floor level through which juvenile and small adult lobster can enter. Lobster are inclined to migrate or forage in the direction of current flow are thus likely to be funneled from one link to the next. Similarly lobster living outside the predator- exclusion perimeter are likely to be funneled with the currents into the ranching area, and so on successively down the row of successive enclosed ranching areas.

Although less efficient than vertical integration, using successively linked ranching areas 214a, 214b, etc. can be employed in addition to or as an alternative to vertical integration. For example, the first ranching area 214a can be provided with artificial settlement and nursery habitats. The settlement and nursery habitats can be algal beds or an artificial calcareous cavern matrix. In addition or in the alternative, drift algae can be maintained in tethered netting, such as the tethered prismatic volumes previously described herein. The second ranching area 214b can provide benthic habitats, which can be naturally occurring, supplemented, or of the artificial type previously described herein. The third ranching area 214c can have natural foraging resources for adult lobster, such as seagrass or algal beds.

According to a preferred embodiment of the invention, casas for adult lobster are most preferably arranged in a plurality of zigzag hedgerows 222 as shown in FIG. 11. The hedgerows 222 are preferably arranged to be substantially parallel to the commonly prevailing water current in the area, which is graphically represented by arrow 224. The substantially parallel arrangement of the hedgerows 222 is intended to minimize disruption of the naturally existing macro currents in the ranching areas 214c and 214d. This reduces the environmental impact of the casas on natural foraging resources, such as seagrass and algal beds, that are naturally existing within the ranching areas 214c and 214d. The advantages of such an arrangement of zigzag hedgerows was previously described herein with reference to FIG. 2.

To reduce construction costs, the intermediate portions of the perimeters between the ranching areas 214a-d can be eliminated. A biomoφhic design such as the one illustrated in FIG. 11 employing a plurality of linked areas can be advantageous, particularly where the territory for permitted lobster ranching is readily available.

FIG. 12

Referring now to FIG. 12 of the drawing, an alternative embodiment for a predator-exclusion perimeter for defining a lobster ranching area 14 is illustrated. According to this embodiment, at least a portion of the predator-exclusion perimeter 300 is formed by simply using a plurality of weights 304 to anchor the footrope of a suitable netting material 302 to the ocean floor 33. The headrope of the netting material 302 is floated at or near the surface 43 with a plurality of suitable floats 306. Inside the ranching area 14, vertically integrated lobster ranching structures are preferably employed, such as previously described casa 44d supported on a suitable spread footing 104d, benthic substrate 84d with transplanted algae 88d growing thereon, and a tethered prismatic volume 90d.

The advantage of the simplified predator-exclusion perimeter 300 is relatively low construction cost. However, the predator-exclusion perimeter 300 may require more repair and replacement maintenance because it is expected to be less resistant to storm damage. In addition, finfish predators are more likely to be able to swim over to top of the netting, especially during heavy wave action.

Although the invention has described with reference to these preferred embodiments, other embodiments can achieve the same results. Variations and modifications of the present invention will be apparent to those skilled in the art without departing from the scope and spirit of the invention.

Claims

Having described the invention, what is claimed is:

1. A method of lobster or crab ranching comprising the steps of:

(a) selecting a marine location that is suitable for supporting the ecology of at least one species of lobster or crab;

(b) excluding finfish predators of the lobster or crab from a ranching area at the selected marine location; and

(c) harvesting marketable-size lobster or crab from the ranching area.

2. A method of lobster ranching according to Claim 1 , wherein the step of excluding predators from the ranching area comprises the step of: forming a predator- exclusion perimeter to define the selected marine ranching area.

3. A method of lobster ranching according to Claim 2, wherein the step of forming a predator-exclusion perimeterfurther comprises: building predator-exclusion sections adjacent an existing shore-line.

4. A method of lobster or crab ranching according to Claim 1, further comprising the step of: providing artificial shelter for the lobster or crab within the ranching area.

5. A method of lobster or crab ranching according to Claim 4, wherein the step of providing artificial shelter for the lobster or crab within the ranching areafurtiier comprises the step of: arranging a plurality of artificial shelters in at least one zigzag hedgerow.

6. A method of lobster or crab ranching according to Claim 5, wherein the step of providing artificial shelter for the lobster or crab within the ranching area further comprises ╧ïie step of: arranging the at least one zigzag hedgerow to be substantially parallel to normally prevailing ocean currents in the ranching area.

7. A method of lobster or crab ranching according to Claim 5, wherein the step of providing artificial shelter for the lobster or crab within the ranching areafurtiier comprises the step of: interconnecting the plurality of artificial shelters in the zigzag hedgerow to increase the stability of the artificial shelters.

8. The lobster product of the method of any one of Claims 1 -7.

9. The crab product of the method of any one of Claims 1-7.

10. A method of lobster ranching comprising the steps of:

(a) excluding predators of juvenile and adult lobsterfrom a marine ranching area; and

(b) harvesting marketable-size lobster from the ranching area.

11. A method of lobster ranching according to Claim 10, further comprising the step of: providing artificial shelter for large juvenile and adult lobster within the ranching area.

12. A method of lobster ranching according to Claim 11 , wherein the step of providing artificial shelter for large juvenile and adult lobster within the ranching area further comprises the step of: arranging the plurality of artificial shelters into at least one zigzag hedgerow.

13. A method of lobster ranching according to Claim 12, wherein the step of providing artificial shelter for large juvenile and adult lobster within the ranching area further comprises the step of: arranging the at least one zigzag hedgerow to be substantially parallel to normally prevailing ocean currents in the ranching area.

14. A method of lobster ranching according to Claim 11 , wherein the step of providing artificial shelter for large juvenile and adult lobster within the ranching area further comprises the step of: interconnecting the plurality of artificial shelters in the zigzag hedgerow to increase the stability of the artificial shelters.

15. A method of lobster ranching according to Claim 11 , further comprising the step of: providing a settlement and nursery habitat for early benthic phase juvenile lobster in the ranching area.

16. A method of lobster ranching according to Claim 15, wherein the step of providing a settlement and nursery habitat for eariy benthic phase juvenile lobster in the ranching area further comprises: anchoring a buoyantly supported containment volume for containing a settlement and nursery habitat in the ranching area.

17. A method of lobster ranching according to Claim 16, wherein the step of anchoring a buoyantly supported containment volume for containing a settlement and nursery habitat further comprises the step of: anchoring the buoyantly supported containment volume such that the containment volume is maintained substantially beneath the ocean surface.

18. A method of lobster ranching according to Claim 16, wherein the step of anchoring a buoyantly supported containment volume for containing a settiement and nursery habitat in the ranching area further comprises the step of: anchoring the buoyantly supported containment volume to the artificial shelter.

19. A method of lobster ranching according to Claim 16, wherein the buoyantly supported containment volume comprises:

(a) at least one buoyant compression member adapted for supporting a netting material to define a substantially enclosed container;

(b) at least one line for anchoring the buoyant compression member.

20. A method of lobster ranching according to Claim 19, wherein the netting material is supported to define a prism.

21. A method of lobster ranching according to Claim 16, wherein the buoyantly supported containment volume comprises:

(a) a first buoyant compression member;

(b) a second buoyant compression member; (c) netting material defining a substantially enclosed container in the shape of a prism and for retaining a settlement and nursery habitat therein, opposed upper edges of the triangular ends of the prism shape of said netting material being supported by said first and second buoyant compression members, respectively; and

(d) a first line attached to the lower comer of a first triangular end of the netting material defining the prism-shaped container;

(e) a second line attached to the lower comer of a second triangular end of the netting material defining the prism-shaped container, whereby when placed in ocean water, the first and second buoyant compression members maintain the opposed upper edges of the triangular ends of the prism-shaped netting material floating upward and stretched pe╧åendicular to the axis of prism shape, and when the first and second lines are anchored spaced-apart from one another below the surface of the ocean, the first and second lines assist in maintaining the axial dimension of the prism shape and assist in holding the lower comers of the netting down, thereby defining a prismatic shape for the containment volume.

22. A method of lobster ranching according to Claim 10, further comprising the step of: providing an artificial benthic habitat for growing juvenile lobster within the ranching area.

23. A method of lobster ranching according to Claim 22, wherein the artificial benthic habitat comprises: an artificial calcareous cavern matrix defining a plurality of small hiding places therein and being a suitable substrate for algae.

24. A method of lobster ranching according to Claim 10, further comprising the step of: providing a settlement and nursery habitat for eariy benthic phase juvenile lobster in the ranching area.

25. A method of lobster ranching according to Claim 24, wherein the settlement and nursery habitat comprise Laurencia.

26. A method of lobster ranching according to Claim 10, further comprising the steps of:

(a) providing artificial shelter for at least the large juvenile and adult lobster within the ranching area; (b) providing an artificial benthic habitat for growing benthic phase juvenile lobster within the ranching area; and

(c) providing a settlement and nursery habitat for eariy benthic phase juvenile lobster within the ranching area.

27. A method of lobster ranching according to Claim 26, wherein the artificial benthic habitat comprises an artificial calcareous cavern matrix defining a plurality of small hiding places therein and providing a suitable substrate for algae.

28. A method of lobster ranching according to Claim 26, wherein the settlement and nursery habitat comprises Laurencia.

29. A method of lobster ranching according to Claim 26, further comprising the step of: vertically integrating the artificial shelter, the artificial benthic habitat, and the settlement and nursery habitat.

30. A method of lobster ranching according to Claim 10, further comprising the steps of:

(a) capturing puerulus from the ocean;

(b) protecting the captured puerulus in a puerulus moult facility until at least the first instar moult into eariy benthic phase juveniles; and

(c) transplanting the juveniles to the lobster ranching area.

31 A method of lobster ranching according to Claim 30, further comprising the step of: setting aside a portion of the early benthic phase juveniles obtained from the captured puerulus for restocking in the wild.

32 A method of lobster ranching according to Claim 30, further comprising the step of: providing a suitable settlement and nursery habitat for eariy benthic phase juveniles in the puerulus moult facility.

33. A method of lobster ranching according to Claim 32, wherein the suitable settlement and nursery habitat comprises red algae.

34. A method of lobster ranching according to Claim 10, further comprising the steps of:

(a) collecting early benthic phase juvenile lobsterfrom outside the ranching area; and (b) transplanting the collected eariy benthic phase juvenile lobster into the ranching area.

35. A method of lobster ranching according to Claim 34, further comprising the step of: providing a settlement and nursery habitat for eariy benthic phase juvenile lobster within the ranching area.

36. A method of lobster ranching according to Claim 35, wherein the step of providing a settlement and nursery habitat for early benthic phase juvenile lobster further comprises the step of: transplanting red algae into the ranching area.

37. A method of lobster ranching according to Claim 10, wherein the step of excluding predators from the ranching area comprises the step of: forming a predator-exclusion perimeter to define the selected marine ranching area.

38. A method of lobster ranching according to Claim 37, wherein the step of forming a predator-exclusion perimeter further comprises the step of: positioning at least one predator-exclusion section at the selected ranching area further comprises the steps of:

(a) positioning a first pier structure at the selected marine location;

(b) positioning a second pier structure spaced-apart from the first pier structure; and

(c) supporting a predator-exclusion material between the fist pier structure and the second pier structure.

39. A method of lobster ranching according to Claim 38, wherein the first pier structure comprises a footing and a pier, and wherein the second pier structure comprises a footing and a pier.

40. A method of lobster ranching according to Claim 38, wherein the predator-exclusion material is netting.

41. A method of lobster ranching according to Claim 38, further comprising the step of: positioning an artificial shelter for adult lobster between the first pier structure and the second pier structure.

42. A method of lobster ranching according to Claim 41 , further comprising the step of: interconnecting the artificial shelter for adult lobster to the first pier structure and the second pier structure.

43. A method of lobster ranching according to Claim 41 , further comprising the step of: forming a benthic habitat on the top of the artificial shelter.

44. A method of lobster ranching according to Claim 43, wherein the benthic habitat comprises a calcareous matrix with algae transplanted thereon.

45. A method of lobster ranching according to Claim 43, further comprising the step of: providing a settlement and nursery habitat for early benthic phase juvenile lobster above the benthic habitat.

46. A method of lobster ranching according to Claim 45, wherein the step of providing a settlement and nursery habitat for eariy benthic phase juvenile lobster further comprises the step of: tethering drift type Laurencia above the benthic habitat

47. A method of lobster ranching according to Claim 45, wherein the step of providing a settlement and nursery habitat for early benthic phase juvenile lobster further comprises the step of: attaching tethered prismatic volumes between the first pier structure and the second pier structure, and transplanting Laurencia into the tethered prismatic volumes.

48. A method of lobster ranching according to Claim 41 , further comprising the step of: positioning at least one selectively operable gate means to the artificial shelterfor selectively directing wild lobsterfrom outside the ranching area through the predator-exclusion perimeter and into the ranching area.

49. The lobster product of the method of any one of Claims 10-48.

50. A method of lobster ranching comprising the steps of:

(a) excluding predators of at least adult lobster from a marine ranching area;

(b) providing artificial shelterfor at least the large juvenile and adult lobster within the ranching area;

(c) providing an artificial benthic habitat for growing benthic phase juvenile lobster within the ranching area;

(d) providing a settlement and nursery habitat for eariy benthic phase juvenile lobster within the ranching area; (e) capturing puerulus from the ocean;

(f) protecting the captured puerulus in a puerulus moult facility until at least the first instar moult into eariy benthic phase juveniles;

(g) transplanting the juveniles to the lobster ranching area; and

(h) harvesting marketable-size lobster from the lobster ranching area.

51. A method of lobster ranching according to Claim 50, wherein the step of excluding predators from the ranching area comprises the step of: forming a predator-exclusion perimeter to define the selected marine ranching area.

52. A method of lobster ranching according to Claim 50, wherein the step of providing artificial shelter for large juvenile and adult lobster within the ranching area further comprises the step of: arranging the plurality of artificial shelters into at least one zigzag hedgerow.

53. A method of lobster ranching according to Claim 52, further comprising the step of: arranging the zigzag hedgerow to be substantially parallel to normally prevailing ocean currents in the ranching area.

54. A method of lobster ranching according to Claim 50, further comprising the step of: providing a settlement and nursery habitat for eariy benthic phase juveniles in the puerulus moult facility.

55. A method of lobster ranching according to Claim 54, wherein the settlement and nursery habitat comprises red algae.

56. A method of lobster ranching according to Claim 50, further comprising the step of: setting aside a portion of the early benthic phase juveniles obtained from the captured puerulus for restocking in the wild.

57. The lobster product of the method of any one of Claims 50-56.

58. A method of lobster ranching comprising the steps of:

(a) providing artificial shelter for at least the large juvenile and adult lobster at a marine location;

(b) providing an artificial habitat for growing benthic phase juvenile lobster within at the marine location;

(c) providing a settlement and nursery habitat for eariy benthic phase juvenile lobster to the marine location; and

(d) harvesting marketable-size lobster from the marine location.

59. A method of lobster ranching according to Claim 58, further comprising the step of: substantially excluding predators of at least adult lobsterfrom a ranching area at the marine location.

60 A method of lobster ranching according to Claim 59, wherein the step of excluding predators from the ranching area comprises the step of: forming a predator-exclusion perimeter to define the selected marine ranching area.

61. A method of lobster ranching according to Claim 60, wherein the step of forming a predator-exclusion perimeter to define the selected marine ranching area further comprises the step of: forming a portion of the predator-exclusion perimeter adjacent to a pre-existing shore-line.

62. A method of lobster ranching according to Claim 58, wherein the step of providing artificial shelter for large juvenile and adult lobster within the ranching area further comprises the step of: arranging the plurality of artificial shelters into at least one zigzag hedgerow.

63. A method of lobster ranching according to Claim 62, further comprising the step of: arranging the at least one zigzag hedgerow to be substantially parallel to normally prevailing ocean currents in the ranching area.

64. A method of lobster ranching according to Claim 58, wherein the artificial benthic habitat comprises: an artificial calcareous cavern matrix defining a plurality of small hiding places therein and providing a suitable substrate for algae.

65. A method of lobster ranching according to Claim 58, wherein the step of providing a settlement and nursery habitat for early benthic phase juvenile lobster in the ranching area further comprises: anchoring a buoyantly supported containment volume for containing the settlement and nursery habitat in the ranching area.

66. A method of lobster ranching according to Claim 65, wherein the step of anchoring a buoyantly supported containment volume for containing a settlement and nursery habitat in the ranching area further comprises the step of: anchoring the buoyantly supported containment volume such that the containment volume is maintained substantially beneath the ocean surface.

67. A method of lobster ranching according to Claim 65, wherein the step of anchoring a buoyantly supported containment volume for containing a settlement and nursery habitat in the ranching area further comprises the step of: anchoring the buoyantly supported containment volume to the artificial shelter.

68. A method of lobster ranching according to Claim 65, wherein the buoyantly supported containment volume comprises:

(a) at least one buoyant compression member adapted for supporting a netting material to define a substantially enclosed container; (b) at least one line for anchoring the buoyant compression member.

69. A method of lobster ranching according to Claim 68, wherein the netting material is supported to define a prism.

70. A method of lobster ranching according to Claim 65, wherein the buoyantly supported containment volume comprises:

(a) a first buoyant compression member;

(d) a first line attached to the lower corner of a first triangular end of the netting material defining the prism-shaped container;

71. A method of lobster ranching according to Claim 58, wherein the settlement and nursery habitat comprises Laurencia.

72. A method of lobster ranching according to Claim 58, further comprising the step of: vertically integrating the artificial shelter, the artificial benthic habitat, and the settlement and nursery habitat.

73. A method of lobster ranching according to Claim 58, further comprising the steps of:

(a) capturing puerulus from the ocean;

(c) transplanting the juveniles to the marine location.

74. A method of lobster ranching according to Claim 73, further comprising the step of: setting aside a portion of the eariy benthic phase juveniles obtained from the captured puerulus for restocking in the wild.

75. A method of lobster ranching according to Claim 73, further comprising the step of: providing a suitable settlement and nursery habitat for early benthic phase juveniles in the puerulus moult facility.

76. A method of lobster ranching according to Claim 75, wherein the suitable settlement and nursery habitat in the puerulus moult facility comprises red algae.

77. The lobster product of the method of any one of Claims 58-76.

78. A predator-exclusion section for use in a marine lobster ranching operation, the predator-exclusion section comprising:

(a) a first pier;

(b) a second pier that is spaced-apart from said first pier; and

(c) a predator-exclusion material supported between said first and second piers.

79. A predator-exclusion section according to Claim 78, wherein said first pier comprises a first footing and a composite steel and cement pier; and wherein said second pier comprises a second footing and a second composite steel and cement pier.

80. A predator-exclusion section according to Claim 78, wherein said predator-exclusion material comprises netting.

81. A predator-exclusion section according to Claim 78, further comprising: an artificial shelter for adult lobster that is interconnected between said first pier and said second pier.

82. A predator-exclusion section according to Claim 81 , wherein said artificial shelter is in the form of a casa having a horizontal top and first and second support legs.

83. A predator-exclusion section according to Claim 81, wherein said artificial shelter is interconnected to between said first pier and said second pier by means of a plurality of tension members.

84. A predator-exclusion section according to Claim 81 , further comprising an artificial calcareous cavern matrix for larger benthic phase juveniles positioned on said casa.

85. A predator-exclusion section according to Claim 81 , further comprising a tethered volume for containing a settlement and nursery habitat, said tethered volume being anchored to said artificial shelter of the predator-exclusion section.

86. A predator-exclusion section according to Claim 85, wherein said tethered volume is in the shape of a prism.

87. A predator-exclusion section according to Claim 81 , further comprising a selectively operable gate means for recapturing wild lobster from outside the predator-exclusion section and directing the lobster into the marine lobster ranch.

88. A buoyant containment volume for use in a marine lobster ranching operation, the buoyant containment volume comprising:

(a) at least one buoyant compression member adapted for supporting a netting material to define a substantially enclosed container; (b) at least one line for holding the buoyant compression member.

89. A tethered volume according to Claim 88, wherein said netting material is supported to define a prism.

90. A tethered prismatic volume for use in a marine lobster ranching operation, the tethered prismatic volume comprising:

(a) a first buoyant compression member;

(e) a second line attached to the lower comer of a second triangular end of the netting material defining the prism-shaped container, whereby when placed in ocean water, the first and second buoyant compression members maintain the opposed upper edges of the triangular ends of the prism-shaped netting material floating upward and stretched pe╧åendicular to the axis of prism shape, and when the first and second lines are anchored spaced-apart from one another, the first and second lines assist in maintaining the axial dimension of the prism shape and assist in holding the lower comers of the netting down, thereby defining the prismatic shape for the tethered prismatic volume.

91. An artificial calcareous cavem matrix for use in lobster ranching, the matrix comprising:

(a) a structural material defining a plurality of recesses and openings of a range of sizes appropriate for at least one benthic phase of juvenile lobster;

(b) a surface material on said structural material that is calcareous, providing a good substrate for algae.

92. The artificial calcareous cavem matrix according to Claim 91 , wherein said structural material is a non-woven material.

93. The artificial calcareous cavem matrix according to Claim 91 , wherein said structural material is selected from the group consisting of polyamide six, high density polyethylene, or any combination thereof.

94. The artificial calcareous cavern matrix according to Claim 91 , wherein the plurality of recesses and openings are of a range of sizes appropriate for use as a settlement and nursery habitat for early benthic stage juveniles.

95. The artificial calcareous cavem matrix according to Claim 91 , wherein the plurality of recesses and openings are of a range of sizes appropriate for use as a benthic habitat for later benthic stage juveniles.

96. The artificial calcareous cavem matrix according to Claim 91 , wherein the surface material is a latex cementitious coating.

97. The artificial calcareous cavem matrix according to Claim 96, wherein said calcareous coating is formed by a mineral acretion technique.

98. A lobster ranch comprising:

(a) a predator-exclusion perimeter;

(b) a plurality of artificial shelters for adult lobster, wherein said plurality of artificial shelters are arranged in at least one zigzag hedgerow.

99. A lobster ranch according to Claim 98, wherein said at least one zigzag hedgerow is further arranged to be substantially parallel to normally prevailing ocean currents in the ranching area.

100. A lobster ranch according to Claim 98, further comprising: a puerulus moult facility.