WO2002082896A1

WO2002082896A1 - Aquaculture transport structure

Info

Publication number: WO2002082896A1
Application number: PCT/GB2002/001678
Authority: WO
Inventors: Manuel De La Vega
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-04-17
Filing date: 2002-04-10
Publication date: 2002-10-24
Anticipated expiration: 2003-10-17
Also published as: GB2374572A; GB2374572B; GB0109434D0

Abstract

When transporting fish which have been caught for the purpose of sea aquaculture (fish farming), it is essential for the transportation cage to arrive as quickly as possible to prevent the fish from being killed if the tensed fishing net collapses. This invention provides a collapsible, floatable aqualcutlure transport structure comprising a plurality of floatable pipe members (2). The compacted planar structure is towed to the area in which the fish have been caught. It is then detached from the towing harness (16) to which it has been attached for towing and is converted into a substantially ring-like structure on to which a weighted transport net can be attached. Hinges (5, 13) in the structure allow for the conversion to the ring-like structure and for the structure to flex with the movement of the sea and possible warping of the pipe members (2), whilst still keeping the ring structure intact.

Description

Aquaculture transport structure

This invention relates to an aquaculture transport structure and is concerned with a structure which can be rapidly transported to a fishing area where entrapped fish are being held pending transfer to a farming location.

Offshore fish aquaculture, also known as fish farming, has been practised for ten years or more in many of the major fishing areas of the world. An offshore fish cage suitable for such fish farming is described in, for example U.S. Patent No.4957064.

Large-scale sea aquaculture (fish farming) occurs in three distinct phases:

1) Fishermen find shoals of the desired fish and entrap them with nets. It is important to keep the nets tense, as fish intended for fish farming need to be kept alive, since if the nets collapse on the fish they will die. This requires several boats pulling the nets from opposing directions to keep them open until a transportation cage arrives.

2) A boat capable of pulling a transportation cage is notified of the position of the fish nets. However conventional transportation cages are rigid and very slow to move through the water. It can take several days for the cage to catch up with the fishermen during which time the fish can die if the net is not constantly kept tense.

3) The fish which have been caught in the nets are transferred to the transportation cage in which they are transported to a farming pool for fattening for the market.

It is important that the fish stay alive as they then have greater commercial value. It is costly to wait for a conventional cage to arrive to transport the fish to an aquaculture site. It is therefore an object of the invention to provide a means for proceeding more rapidly to the fishing area so as to reduce the time that the entrapped fish are held in the fishing nets and the time spent by the fishermen in keeping the nets tense pending arrival of the transportation cage.

According to the present invention there is provided a collapsible, floatable structure for transportation of live fish from an entrapment site to an aquaculture site, the structure comprising a plurality of floatable longitudinally extending members flexibly connected end to end to adjacent members by rotatable flexible joints so as to be capable in use of forming a substantially ring-like structure, the arrangement being such that for transportation of the structure to the entrapment site the members can be folded together to form a compact generally planar structure capable of being towed through the water at a relatively high speed, whilst for towing to a desired aquaculture site the members can be unfolded and formed into a substantially ring-like structure on to which a weighted net for transportation of the live fish can be attached.

The floatable members are advantageously connected by flexing hinges, which allow the structure to flex in the horizontal axis whilst remaining fixed in the vertical axis and the structure to be collapsed for towing purposes, and by rotatable joints which serve to prevent the hinges from being damaged under strain should the floatable members warp due to heat.

The structure comprises a plurality, for example 8, 10, 12 or 14, of floatable longitudinally extending members sufficient to form a polygonally-shaped structure when in the unfolded state. In a preferred embodiment of the invention, the structure comprises twelve longitudinally extending members so that in the unfolded state, the structure takes the form of a dodecagon.

The unfolded transportation structure is advantageously provided with a plurality of diagonal ties, e.g. three ties, to assist in maintaining the shape of the structure when the live fish are being transported to the desired aquaculture site. The ties may be made from suitable nylon cord.

For a better understanding of the invention and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings in which: -

Figure 1 is a plan view of the transportation structure in an unfolded opened mode;

Figure 2 is a plan view showing the structure in a closed mode for speedy towing;

Figure 3 is a side view showing the closed structure being towed by a boat to which the structure is connected by means of a supporting harness;

Figure 4 shows in detail a hinge joint and pipe construction viewed from the side;

Figure 5 shows in detail a flexing hinge joint when viewed from above;

Figure 6 shows in detail a locking plate when closed, viewed from above;

Figure 7 shows in detail a flexing hinge plate, viewed from above; and

Figure 8 shows a locking pin viewed (a) from above and (b) from the side.

Referring to the drawings, the structure comprises twelve pipe members 2 each containing a solid floatable foam rod 1. At one end of each pipe member 2 is an end plate 3 on to which a hinged tongue 13 is fixed, supported by support plates 6. At the other end of the pipe member 2 there is another hinged tongue 13 attached via a rotatable joint 4 to an end plate 3. The pipe members 2 are connected to adjacent pipe members by means of hinged plates 5 held together by fixed locking pins 7. Each structure contains eleven flexing hinged plates 5 (Fig 7) and one locking hinged plate comprising male 10 and female 11 parts and a spring loaded locking bolt 12 with a removable bolt pin 15 (Fig 6). The structure is transported with the pipe members 2 lined up in a compact planar structure as shown in Figures 2 and 3. Flexing hinges 9 are used to hold the pipe members in a linear configuration as shown. The two halves of the separated locking plate 10,11 (Fig 6) are used to connect the pipe members to the harness 16 as shown in Figure 3.

Upon arrival at the area where the fish have been caught, the front of the structure is lowered on to the water and the two halves of the locking plate 10, 11 are released from their connections on the harness 16. The structure is opened one hinge at a time by removing the locking pin 8, moving the pipe member, then replacing the locking pin 8 into the appropriate hole in the hinged tongue 13. The flexing hinges 5 are opened first and finally the locking plate 10,11 is clipped together and the removable bolt pin 15 is unscrewed so as to prevent the joint from accidentally opening. This produces the final structure (Fig 1) on to which a weighted net can be attached to transport the fish. The structure is attached to the transport boat using ropes attached to the midpoint holes 14 on the flexing hinged plates (Fig 7).

To collapse the structure after transportation, the steps described in the foregoing paragraph are carried out in the reverse order.

Claims

CLAIMS:

1. A collapsible, floatable structure for transportation of live fish from an entrapment site to an aquaculture site, the structure comprising a plurality of floatable longitudinally extending members flexibly connected end to end to adjacent members by rotatable flexible joints so as to be capable in use of forming a substantially ring-like structure, the arrangement being such that for transportation of the structure to the entrapment site the members can be folded together to form a compact generally planar structure capable of being towed through the water at a relatively high speed, whilst for towing to a desired aquaculture site the members can be unfolded and formed into a substantially ring-like structure on to which a weighted net for transportation of the live fish can be attached.

2. A collapsible structure as claimed in Claim 1 , wherein adjacent pairs of the floatable members are joined together by a hinged plate provided with means for both vertical and horizontal movement.

3. A collapsible structure as claimed in Claim 2, wherein the hinged plate is also provided with means for rotational movement to prevent damage if the members warp in use.

4. A collapsible structure as claimed in Claim 2 or 3, wherein one adjacent pair of the floatable members is connected by a lockable plate having male and female interlocking members and provided with removable locking means which can be used to allow construction of the ring-like structure at the entrapment site.

5. A collapsible structure as claimed in any preceding claim, wherein the structure is provided with means for attachment to a tow line for transport to the entrapment site.

6. A collapsible structure as claimed in any preceding claim, wherein the floatable members each comprise a pipe member containing a solid rod of foam material.

7. A collapsible structure as claimed in any preceding claim, wherein the structure comprises 8, 10, 12 or 14 floatable longitudinally extending members.

8. A collapsible structure as claimed in Claim 2, 3, 4, 5 or 6, wherein the structure comprises 12 floatable longitudinally extending members which when joined together take the form of a dodecagon.