WO2022039602A1

WO2022039602A1 - Fish pot for catching and raising fish

Info

Publication number: WO2022039602A1
Application number: PCT/NO2021/050178
Authority: WO
Inventors: Tore Halvorsen
Original assignee: Innomar As
Priority date: 2020-08-19
Filing date: 2021-08-19
Publication date: 2022-02-24
Also published as: NO20210993A1; NO346690B1

Abstract

A pot (1) for catching fish, the pot (1) comprising; an upper portion (11) with a pot top (110) provided with a buoyancy body (2) arranged to position a portion of the pot top (110) at a water surface (99); a lower portion (13) with a pot bottom (120); a surrounding side wall (14) which extends from the pot top (110) to the pot bottom (120), the side wall (14) and the pot bottom (120) forming a closed enclosure (19) for the fish; at least one first inlet (17) from the surroundings into the enclosure (19) through the surrounding side wall (14), the first inlet (17) debouching into the lower pot chamber (15); and an internal partition (40) in the enclosure (19), the partition (40) creating a lower pot chamber (15) with a first volume (150) and the partition (40) creating an upper pot chamber (25) with a second volume (250), and the partition (40) comprising a second inlet (37) between the lower pot chamber (15) and the upper pot chamber (25). The pot (1) comprises: a first lure positioned in the lower pot chamber (15); a second lure positioned in the upper pot chamber (25), the upper pot chamber (25) being open towards the water surface (99), and at least a portion of the partition (40) being arranged to be lifted in a water column (98) to reduce the second volume (250). A method for catching fish with the pot (1) is described as well.

Description

FISH POT FOR CATCHING AND RAISING FISH

The invention relates to a pot for catching fish. In particular, the pot relates to catching fish in the vicinity of a farming facility. More specifically, the pot relates to a pot that is large enough for and arranged for being secured to the frame mooring of a farming facility. The pot is arranged to attract fish with a lure. The lure may be one or more lights. The pot according to the invention is divided into a lower pot chamber and an upper pot chamber in such a way that the fish can swim from the lower pot chamber through an inlet and into the upper pot chamber, but the fish cannot swim the other way. The bottom of the upper pot chamber can be lifted to crowd together fish present in the upper pot chamber, so that the fish can be pumped into a wellboat, for example. The lower pot chamber continues catching fish independently of what work operations are being carried out in the upper pot chamber.

Background of the invention

In fishing for so-called whitefish, for example cod, it is known to use a trawl, a Danish seine, a net and a longline. A substantial drawback in fishing with a trawl and partly also fishing with a Danish seine is that the fish suffer crushing damage when large amounts of fish are crowded together in the trawl or the net. It is also known that trawling can give poor bleeding of the fish because it may take a long time to gut and bleed all the fish. It is also a problem that the trawl may damage the sea floor. Trawls and nets also shed considerable amounts of microplastics because of abrasion against the sea floor. Research shows that the proportion of quality fish in trawling may be as small as 50 per cent, depending on the size of the catch.

Fishing with longlines and hand lines are examples of fisheries that are gentler than fishing with a trawl, and these fishing methods are much used by smaller fishing boats. For these types of fishing gear, research shows a quality proportion of 71 and 91 per cent, respectively. A drawback of the hand line and the longline is that hooks are used, which stresses the fish and causes wounds in the fish. A pot, for example a trap net or a cod pot, is the gentlest fishing gear and is well suited for fish that are to be carried alive to the market. The pot comprises an enclosure into which the fish are lured, and in which the fish are kept without being harmed. The fish may have access to food in the pot. Pot-fishing therefore makes it possible for fishermen to avoid fishing in bad weather, as the pots may be set before the storm sets in and be emptied when the storm is over.

The drawback of a pot and a trap net is that these types of fishing gear are not very effective for catching fish, and therefore they have gained only limited ground among commercial fishermen. At the same time, the demand for wild fish of high quality increases. The fishing industry is therefore in search of new catching methods that are both gentle and effective.

It is known that fish gather on the outside of the net cages in farming facilities for fish. Uneaten feed sinks through the enclosures and may be eaten by wild fish on the outside of the enclosure. Both because there may be a prohibition against fishing in the vicinity of the net cages, and because it is difficult to use conventional, commercial fishing gear in the vicinity of the net cages, it is difficult to utilize this fish resource.

There is therefore a need to be able to catch this fish in an effective way. There is also a need to keep such caught wild fish in an enclosure until the fish have emptied their intestines. There is also a need to be able to guide this fish into, for example, a wellboat to be able to transport caught fish away from the farming facility.

The invention has for its object to remedy or reduce at least one of the drawbacks of the prior art or at least provide a useful alternative to the prior art.

The object is achieved through the features that are specified in the description below and in the claims that follow.

General description of the invention

The invention is defined by the independent claims. The dependent claims define advantageous embodiments of the invention.

In the description of the invention, the terms inlet, pot and net cage occur: The following may be understood by these terms:

By an inlet may be understood an inlet arranged to guide fish and sea animals into a pot chamber and simultaneously prevent the fish and the sea animals from moving out of the pot chamber via the inlet. The inlet is also termed a funnel.

• By a pot may be understood, in what follows, a type of passive fishing gear with one or more inlets for fish or crustaceans.

• By the terms net cage and traditional net cage may be understood an enclosure for keeping and raising of fish.

In a first aspect, the invention relates more specifically to a pot for catching fish, the pot comprising;

- an upper portion with a pot top provided with a buoyancy body arranged to position a portion of the pot top at a water surface;

- a lower portion with a pot bottom;

- a surrounding side wall extending from the pot top to the pot bottom, the side wall and the pot bottom forming a closed enclosure for the fish; and

- at least one first inlet from the surroundings into the enclosure through the surrounding side wall, the first inlet debouching into the lower pot chamber, and an internal partition in the enclosure, the partition creating a lower pot chamber with a first volume and the partition creating an upper pot chamber with a second volume, and the partition comprising a second inlet between the lower pot chamber and the upper pot chamber. The pot comprises:

- a first lure positioned in the lower pot chamber;

- a second lure positioned in the upper pot chamber, the upper pot chamber being open towards the water surface, and at least a portion of the partition being arranged to be lifted in a water column to reduce the second volume.

The pot may comprise a third inlet, the the third inlet debouching into the upper part of the lower pot chamber. The third inlet may extend peripherally along the circumference of the surrounding side wall.

The first inlet may be slot-shaped. The second inlet may be slot-shaped. Trials carried out by the applicant have shown that it is more difficult for the fish to swim out of a slot-shaped opening than a round opening.

The first inlet may extend peripherally along the circumference of the surrounding side wall. In one embodiment, the first inlet may surround the pot chamber. The third inlet may extend peripherally along the circumference of the surrounding side wall. In an alternative embodiment, the first inlet may surround the pot chamber. In an alterna- tive embodiment, the third inlet may surround the pot chamber. The effect of the first inlet, alternatively the third inlet, or alternatively both the first inlet and the third inlet, surrounding the lower pot chamber is that the fish can swim into the pot from any horizontal direction.

A plurality of first inlets and/or a plurality of third inlets may be arranged in different vertical and/or horizontal positions on the side wall. The effect of this is easier access for the fish to the lower pot chamber so that the pot becomes a more effective piece of fishing gear.

The pot may be arranged for a permanent positioning in a water column, also when it is to be emptied of catch.

The surrounding side wall may be permeable or tight. The surrounding side wall may be formed of a net. The net may have a mesh adapted for the fish that is to be caught.

The pot may be provided with a bottom ring. The bottom ring may be arranged to keep the enclosure extended and submerged in the water column to provide as large an effective volume as possible in the lower pot chamber. The bottom ring may comprise a plastic pipe.

The first lure may comprise a light-emitting body. The second lure may comprise a light-emitting body. The effect of the first lure is that animal plankton, for example krill, can be lured into the lower pot chamber. It is known that krill seek light. Krill are a bait for fish. Thereby the fish will be lured into the pot chamber by the krill that have already been lured into the pot chamber by the first lure.

The first lure may comprise a plurality of light-emitting bodies arranged to be turned on and off in a sequence along a string. The second lure may comprise a plurality of light-emitting bodies arranged to be turned on and off in a sequence along a string. The sequence may be arranged in such a way that it appears as if a light is moving upwards in the water column inside the lower pot chamber. Correspondingly, the sequence may be arranged in such a way that it appears as if a light is moving upwards in the water column inside the upper pot chamber. Each light-emitting body may be turned on and off individually. The first and lure and the second lure may be arranged to glow in a coordinated sequence. The first lure and the second lure may be attached to a string extending through the second inlet.

The first lure may be positioned in an axial centre portion of the lower pot chamber. The effect of the central position is that the plankton will gather at the centre of the lower pot chamber, and that the fish will also to a great extent stay at the centre of the pot chamber and to a small extent try to get out of the pot chamber.

By providing a light sequence in which a light-emitting body is turned off and an above-lying light-emitting body is turned on, animal plankton and fish can be lured upwards in the water column by means of the first lure and by means of the second lure. The first lure and the second lure may be arranged to be coordinated so that they appear to be one lure.

The pot may include means for registering biomass in the pot cage.

The effect of registering the biomass in the pot cage is that an operator or a control system may get information about the amount of fish that are in the pot chamber in order thereby to take various actions, for example catching the fish, feeding the fish or turning the first lure and/or the second lure on and off. Feeding of the fish may take place in the lower pot chamber. Feeding of the fish may take place in the upper pot chamber.

The registering may be done by using a biomass sensor which may register at least one of, but not limited to, the following measurement parameters; the amount of biomass, the position of the biomass and the number of fish.

The pot may be arranged to lift at least a portion of the partition in a water column, with the lower pot chamber hanging below the partition. Through this, a reduction in the volume of the upper pot chamber is achieved so that the fish in the upper pot chamber are crowded. Thereby it will be easier to crowd the fish further with, for example, a small shore seine. The crowded fish may be conveyed into, for example, a wellboat with a fish pump, as is known in the art. The fish may be crowded together by lifting the partition so that the fish can be conveyed out of the upper pot chamber with a fish pump without using a small shore seine. The second inlet may be closed when the partition is lifted. The volume of the lower pot chamber may be constant below the partition. The lower pot chamber may continue fishing while the upper chamber is being emptied.

Fish in the upper pot chamber may be kept separate from the fish in the lower pot chamber by closing the second inlet. The fish in the upper pot chamber may be starved before they are transferred to, for example, a wellboat from the second pot chamber. The second lure may be passive, whereas the first lure may be active, when the fish in the upper pot chamber are kept separate from the fish in the lower pot chamber.

In a second aspect, the invention relates more specifically to a method for catching fish with a pot. The method comprises:

- positioning a pot, as described in the foregoing, in a water column;

- luring fish into the lower pot camber by activating the first lure; and

- luring fish into the upper pot chamber from the lower pot chamber by activating the second lure.

The method may comprise turning a plurality of light-emitting bodies on and off in a sequence from the bottom and upwards along a string in the lower pot chamber to lure fish in the lower pot chamber upwards in the water column.

The method may comprise turning a plurality of light-emitting bodies on and off in a sequence from the bottom and upwards along a string in the upper pot chamber to lure fish in the lower pot chamber through the second inlet and into the upper pot chamber.

The method may comprise lifting at least a portion of the partition to crowd the fish together in the reduced volume of the upper pot chamber.

The method may comprise continuing to catch fish in the lower pot chamber while fish are being crowded together in the upper pot chamber.

The method may comprise positioning the pot in a frame mooring of a farming facility for fish. This has the advantage of the pot being attachable to an existing frame mooring of the farming facility. It also has the advantage of enabling feed to be conveyed to the pot from a central feeding plant of the farming facility, as is known in the art. Feed may be conveyed to the uppermost pot chamber, or feed may be conveyed to the lower pot chamber. Feed may be conveyed to both chambers.

In what follows, an example of a preferred embodiment is described, which is visualized in the accompanying drawings, in which:

Figure 1 shows a pot with a lower pot chamber and an upper pot chamber in perspective;

Figure 2 shows the pot viewed from above;

Figure 3 shows a section of figure 2; Figure 4 shows the pot where the volume of an upper pot chamber has been reduced by lifting a partition between the upper pot chamber and a lower pot chamber; and

Figure 5 shows a simplified top view, on a smaller scale, of a farming facility for fish that includes the pot.

Reference is made first to figures 1 to 4, in which a pot 1 for catching fish is shown. The pot 1 comprises an upper portion 11 with a pot top 110 provided with a buoyancy body 12 arranged to position a portion of the pot top 110 at a water surface 99, a lower portion 13 with a pot bottom 120, and a surrounding side wall 14 extending from the pot top 110 and to the pot bottom 120. In the figures, the buoyancy body 12 is shown as an annular floating ring 111 of a kind known per se.

The side wall 14 and the pot bottom 120 form an enclosure 19 for the fish. The enclosure 19 is divided into a lower pot chamber 15 and an upper pot chamber 25 by a partition 40. The partition 40 includes an elongated second inlet 37 for the fish, where the second inlet 37 extending upwards and into the upper pot chamber 25. The second inlet 37 is shown positioned at the centre of the pot 1. The lower pot chamber 15 forms a volume 150. The upper pot chamber 25 forms a volume 250.

The lower pot chamber 15 is shown with two inlets 17, 18 for the fish, the two inlets 17, 18 extending peripherally along the side wall 14. The first inlet 17 is positioned in a lower part of the lower pot chamber 15, and a third inlet 18 is positioned in an upper part of the lower pot chamber 15. Thereby, fish may swim into the lower pot chamber 15 from several directions and at different heights in a water column 98.

The partition 40 comprises an elongated inlet 37 for the fish, the inlet 37 extending upwards into the upper pot chamber 25.

A string 130 is positioned at the centre of the pot 1 and extends from the pot top 110 and down to the pot bottom 120. A first portion 136 of the string 130 is positioned in the lower pot chamber 15. A second portion 137 of the string 130 is positioned in the upper pot chamber 25.

The string 130 comprises lures for attracting fish from the outside of the pot. In the figures, the lures are shown as a first lure in the form of a plurality of light-emitting bodies 133a positioned in the lower pot chamber and a second lure in the form of a light-emitting body 133b positioned in the upper pot chamber. One or more of the light-emitting bodies 133a can be activated to lure animal plankton, such as krill (not shown), into the lower pot chamber 15. Krill are bait for the fish, so that the fish are lured into the lower pot chamber 15 through the inlets 17, 18.

One or more biomass sensors 134 can register the amount of fish by means of acoustic signals 135, such as an echo sounder, in the lower pot chamber 15. When the amount of fish in the lower pot chamber 15 exceeds a defined or desired value, one or more of the light-emitting bodies 133a may be turned off and on so that the krill that are in the lower pot chamber 15 are lured upwards in the water column 98 in a direction towards the upper pot chamber 25. When the krill follow the light upwards in the enclosure 19, the fish will follow the krill. The partition 40 is funnel-shaped so that the fish are guided towards the centre of the partition 40 and the second inlet 37.

When the fish are gathered in the upper part of the lower pot chamber 15, the lightemitting bodies 133a of the first lure may be turned off, and the light-emitting bodies 133b of the second lure may be turned on. The krill will then swim up through the inlet 37 and lure the fish along up into the upper pot chamber 25.

When the upper pot chamber 25 is full of fish, the inlet 37 may be closed, and the upper pot chamber can be emptied of fish, for example by means of a fish pump (not shown). The fish may be conveyed into a wellboat (not shown), for example.

When the fish in the upper pot chamber 25 are to be caught, the fish can be crowded by lifting at least a part of the partition 40 as shown in figure 4, so that the volume 250 formed by the upper pot chamber 25 is reduced. Because the fish that are to be crowded are gathered in an upper portion of the enclosure 19, the crowding will be considerably easier and less extensive than when fish are being crowded in a conventional cage where the crowding includes lifting the entire enclosure. The volume 150 formed by the lower pot chamber 15 is maintained while the volume 250 is being reduced. A bottom ring 131 keeps the pot 1 extended. The bottom ring 131 helps to maintain the volume 150 when the volume 150 is being reduced. Thereby, the lower pot chamber 15 can continue catching fish independently of what work operations are carried out in the upper pot chamber 25.

The first end portion 137 of the string 130 may be provided with a radio transmitter (not shown) and may be connected to an energy supply (not shown). In figures 1 and 3, a second end (132) belonging to the string 130 is shown hanging freely above the pot bottom 120.

Reference is now made to figure 5. A farming facility 95 comprises a plurality of cages

2, a pot 1, a feed barge 92 and a frame mooring 96. The pot 1 is shown with the same diameter as the cages 2 and may advantageously have an enclosure 19 of the same volume as the enclosures belonging to the cages 2. The pot 1 is arranged to be moored to the frame mooring 96 of the farming facility 95. Around and between the cages 2 and the pot 1, there may be wild fish (not shown) and fish that may have escaped from the cages 2.

By positioning at least one pot 1 in a farming facility 95, fish that are outside the cages 2 may be lured into the pot 1 and caught there. The fish in the pot 1 may be fed in the same manner as the fish in the cages 2.

The pot 1 is positioned above a sea floor 88 as shown in figure 3. The pot bottom 120 is closed and of a conical shape so that dead fish and waste from the enclosure 19 can be collected and pumped out of the enclosure 19 via a pump system 140.

It should be noted that all the above-mentioned embodiments illustrate the invention, but do not limit it, and persons skilled in the art may construct many alternative embodiments without departing from the scope of the attached claims. In the claims, reference numbers in brackets are not to be regarded as restrictive.

The use of the verb "to comprise" and its different forms does not exclude the presence of elements or steps that are not mentioned in the claims. The indefinite article "a" or "an" before an element does not exclude the presence of several such elements.

The fact that some features are indicated in mutually different dependent claims does not indicate that a combination of these features cannot be used with advantage.

Claims

C l a i m s A pot (1) for catching fish, the pot (1) comprising:

- an upper portion (11) with a pot top (110) provided with a buoyancy body (2) arranged to position a portion of the pot top (110) at a water surface (99);

- a lower portion (13) with a pot bottom (120);

- a surrounding side wall (14) which extends from the pot top (110) to the pot bottom (120), the side wall (14) and the pot bottom (120) forming a closed enclosure (19) for the fish;

- at least one first inlet (17) from the surroundings into the enclosure (19) through the surrounding side wall (14), and the first inlet (17) debouching into the lower pot chamber (15); and

- an internal partition (40) in the enclosure (19), the partition (40) creating a lower pot chamber (15) with a first volume (150) and the partition (40) creating an upper pot chamber (25) with a second volume (250), and the partition (40) comprising a second inlet (37) between the lower pot chamber (15) and the upper pot chamber (25), c h a r a c t e r i z e d i n that the pot (1) comprises:

- a first lure positioned in the lower pot chamber (15);

- a second lure positioned in the upper pot chamber (25), the upper pot chamber (25) being open towards the water surface (99), and at least a portion of the partition (40) being arranged to be lifted in a water column (98) to reduce the second volume (250). The pot (1) according to claim 1, wherein the pot (1) comprises a third inlet (18), the third inlet (18) debouching into the upper part of the lower chamber (15). The pot (1) according to any one of the preceding claims, wherein the first inlet (17) is slot-shaped. The pot (1) according to any one of the preceding claims, wherein the second inlet (37) is slot-shaped. The pot (1) according to any one of the preceding claims, wherein the first lure comprises a light-emitting body (133a). The pot (1) according to any one of claims 1 to 4, wherein the second lure comprises a light-emitting body (133b). The pot (1) according to claim 5, wherein the first lure comprises a plurality of light-emitting bodies (133a) arranged to be turned on and off in a sequence along a string (130). The pot (1) according to claim 6, wherein the second lure comprises a plurality of light-emitting bodies (133b) arranged to be turned on and off in a sequence along a string (130). The pot (1) according to claims 7 and 8, wherein the first and lure and the second lure are arranged to shine in a coordinated sequence. The pot (1) according to claims 7 and 8, wherein the first lure and the second lure are attached to a string (130) extending through the second inlet (37). The pot (1) according to any one of the preceding claims, wherein the volume (150) of the lower chamber (15) is constant below the partition (40). A method for catching fish with a pot (1), c h a r a c t e r i z e d i n that the method comprises:

- positioning a pot (1) according to claim 1 in a water column (98);

- luring fish into the lower pot camber (15) by activating the first lure; and

- luring fish into the upper pot chamber (25) from the lower pot chamber (15) by activating the second lure. The method according to claim 12, wherein the method comprises turning a plurality of light-emitting bodies (133a) on and off in a sequence from the bottom and upwards along a string (130) in the second pot chamber (15) to lure fish in the lower pot chamber (15) upwards in the water column. The method according to claim 12, wherein the method comprises turning a plurality of light-emitting bodies (133b) on and off in a sequence from the bottom and upwards along a string (130) in the upper pot chamber (25) to lure fish from the lower pot chamber (15) through the second inlet (37) and into the upper pot chamber (25). The method according to claim 12, wherein the method comprises lifting at least a portion of the partition (40) to crowd fish together in the reduced volume (250) of the upper pot chamber (25). The method according to claim 15, wherein the method comprises continuing to catch fish in the lower pot chamber (15) while fish are being crowded together in the upper pot chamber (25). The method according to claim 12, wherein the method comprises position- ing the pot (1) in a frame mooring (96) of a farming facility (95) for fish.