CA2065253A1 - Scallop fishing equipment - Google Patents
Scallop fishing equipmentInfo
- Publication number
- CA2065253A1 CA2065253A1 CA 2065253 CA2065253A CA2065253A1 CA 2065253 A1 CA2065253 A1 CA 2065253A1 CA 2065253 CA2065253 CA 2065253 CA 2065253 A CA2065253 A CA 2065253A CA 2065253 A1 CA2065253 A1 CA 2065253A1
- Authority
- CA
- Canada
- Prior art keywords
- bag
- frame
- mouth
- scallops
- water
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 235000020637 scallop Nutrition 0.000 title claims abstract description 35
- 241000237509 Patinopecten sp. Species 0.000 title claims abstract description 10
- 241000237503 Pectinidae Species 0.000 claims abstract description 25
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 22
- 239000007921 spray Substances 0.000 claims description 4
- 239000000463 material Substances 0.000 claims 1
- 241000237519 Bivalvia Species 0.000 description 6
- 235000020639 clam Nutrition 0.000 description 6
- 239000004576 sand Substances 0.000 description 5
- 230000006378 damage Effects 0.000 description 4
- 239000011435 rock Substances 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 101000740224 Homo sapiens Protein SCAI Proteins 0.000 description 1
- 102100037197 Protein SCAI Human genes 0.000 description 1
- -1 are bivalve molluscsO However Species 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
Classifications
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01K—ANIMAL HUSBANDRY; AVICULTURE; APICULTURE; PISCICULTURE; FISHING; REARING OR BREEDING ANIMALS, NOT OTHERWISE PROVIDED FOR; NEW BREEDS OF ANIMALS
- A01K80/00—Harvesting oysters, mussels, sponges or the like
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Environmental Sciences (AREA)
- Animal Husbandry (AREA)
- Biodiversity & Conservation Biology (AREA)
- Mechanical Means For Catching Fish (AREA)
Abstract
Scallop fishing apparatus has water jets (22) which cause stationary scallops to be lifted from the ocean bottom into the path of the open mouth of the collecting bag (16) so as to be caught thereby as the equipment is dragged along an ocean bottom. Such jets (72) may be provided by nozzles mounted on a transverse manifold pipe (20) carried by the frame (14) and supplied with water under pressure by a pump mounted on the towing vessel or the frame and appropriately connected to the manifold (20).
Description
WO ')1/~)31:~ 2 0 (~ ~ ?, r; 3 ~CI/~A~)0/~J0~7.51 :
SCAI.LOP FI.SHING EQUIPMENT
This invention relates to scallop fishing equipment.
Scallops, like claims, are bivalve molluscsO
However, scallops can swim by opening and closing the valves, whereas clams cannot. Usually, when at rest, scallops simply rest on the bottom on a body of water (hereinafter generally referred to as an ocean), and may be in shallow depressions if the bottom of the ocean is soft. On the other hand, clams generally tend to be found buried or partly buried in sand or mud at the bottom of an ocean.
In the past, fishing for scallops has usually been carried out with equipment comprising a collecting bag whose mouth is attached to a rectangular frame to hold the mouth of the bag open, and a towing bridle attached to and extending forwardly of ~he frame for connection to a tow line, generally known as a towing warp. There are two principal ways of causing scallops to enter the collecting bag as the equipment is dragged along an ocean bottom.
The scallops may be swept up into the ~ag by a sweep chain which forms the lower leading edge of the bag at its open end, or may be physically guided up and over the lower part of the fram~ and into the mouth of the bag by suitably angled teeth on the front of the lower part of the frame, i.e. a toothed rake technique.
Althsugh the toothed rake technique is more SUB~TITUTE SHEE~
.. . ~ . ~ . . . ` . ~
..
., ~ . .
-: `
. .
WO~J1/0315X ~ 3 l~cl/cA90tor3~74 ~
SCAI.LOP FI.SHING EQUIPMENT
This invention relates to scallop fishing equipment.
Scallops, like claims, are bivalve molluscsO
However, scallops can swim by opening and closing the valves, whereas clams cannot. Usually, when at rest, scallops simply rest on the bottom on a body of water (hereinafter generally referred to as an ocean), and may be in shallow depressions if the bottom of the ocean is soft. On the other hand, clams generally tend to be found buried or partly buried in sand or mud at the bottom of an ocean.
In the past, fishing for scallops has usually been carried out with equipment comprising a collecting bag whose mouth is attached to a rectangular frame to hold the mouth of the bag open, and a towing bridle attached to and extending forwardly of ~he frame for connection to a tow line, generally known as a towing warp. There are two principal ways of causing scallops to enter the collecting bag as the equipment is dragged along an ocean bottom.
The scallops may be swept up into the ~ag by a sweep chain which forms the lower leading edge of the bag at its open end, or may be physically guided up and over the lower part of the fram~ and into the mouth of the bag by suitably angled teeth on the front of the lower part of the frame, i.e. a toothed rake technique.
Althsugh the toothed rake technique is more SUB~TITUTE SHEE~
.. . ~ . ~ . . . ` . ~
..
., ~ . .
-: `
. .
WO~J1/0315X ~ 3 l~cl/cA90tor3~74 ~
efficient, such equipment i~ only practical where th~
ocean bottom is smooth soft sand or mud free of rocks.
This is usually not the case in the off-shore fishing areas of Canada and the United States o~ America, where most ocean bottoms comprise hard packed sand, a sand/gravel composite and/or rocks of varying sizes. such hard bottoms cause the teeth to be broken o~f. With such hard bottoms therefore, it is usual to use the less efficient sweep equipment.
Unfortunately, both types of equipment caùse unacceptably high destruction of uncaught scallops, namely as a result of the collecting bag being dragged over uncaught scallops. This is particularly serious because the usual practice is to make several passes over the same area, i.e. to drag the e~uipment several times along the same stretch of ocean floort to increase the catch from the area concerned.
There is therefore a need ~or improved scallop fishing equipment o~ the sweep kind which catches scallops more efficiently than known equipment of this kind.
According to the present invention, water jets are used to cause stationary scallups to be lifted from the ocean bottom ~nto ~he path of the open mouth o~ the collecting bag so as to be caught thereby as the equipment is dragged along an ocean bottom. Such jets may be provided by nozzles mounted on a transverse manifold pipe carried by the frame and supplied with water under pressure by a pump mounted on the towing vessel or the "
5~BsllTuTE SHEE~i , . ' ;':, , ' . ' ' ~ '' ' ` , , ` ' ' ` `
,~ . . .
vo ~ )3l:~x ~ ~3 !; ~ ~ J .3 1~cr/c~)o f fra~e and appropriately connected to the manifold.
Advant~geously, the water jets form a diffuse spray.
The invention substantially increases the efficiency of the sweep chain type of scallop fishing equipmellt. This type of equipment can therefore be used efficiently with soft as well as hard ocean bottoms.
There is less destruction of uncaught scallops because more scallops are caught in a single pass over a given area. ~lso, fewer passes are required to catc~l the same number of scallops compared to prior art equipment.
The present invention is substantially different from known hydraulic dredging equipment which is used to catch clams. As mentioned earlier, clams are buried or partly buried in sand or mud, and the hydraulic dredging equipment is used to dig clams out of the ocean bottom with the aid of water jets and a carrier ramp assembly set to travel at a depth of several inches below the ocean bottom to scoop up clams from a trough created by the water jets. This is in contrast to the present invention in which water jets are used to cause scallops to be lifted upwardly from the ocean bed so as to pass into the mouth of the aollecting bag.
One embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings, of which: -Figure 1 is a diagrammatic plan view of scallopfishing equipment in accordance with the invention, and SUBSTITUTE SHEET
. .
, .
~V(~9l/~3l~ ,3~ CI/CA90/~J(3~7B ~-(~, -- 4 ~
Figure 2 is a diagrammatic side YieW of the equipment showing how scallops are caught as the equipment is dragged along ~n ocean bottom.
Referring to the drawings, scallop fishing equipment includes an upright rectangular open frame ~2 with a towing bridle 14 secured to the front thereof. The chain link bag 16 has its open end secured to the periphery of the frame 12, which accordingly maintains the bag 16 in an open configuration. When dragged along an ocean bottom, the lower edge portion 18 of the open end o~
the ~ag 16 assumes a rearwardly-extending forwardly concavely curved configuration, as indicated in Figure 1~
As so far described, the scallop fishing equipment is conventional. In use, the eguipment is dragged along an ocean bottom by a towing vessel so that some of the scallops on th~ ocean bottom pass over the lower front edge portion 18 o~ ~he bag 16 and are therefore caughtO
Some scallops may also be caught "in flight" while they are in motion above the ocean bottom and in the path of the open mouth o~ the bag 16. ~s indicated earlier, the frame 12 and bag 16 will pass over and probably damage or kill many uncaught scallops.
In accordance with the invention, a manifold pipe is secured transversely across the ~rame 12 at a position slightly below mid-height level of the frame 12.
A series o~ rea~ardly and downwardly connected nozæles 22 are fitted ko the manifold pipe 20, and an inlet pipe 24 SlL)BSTITUTE S~ET
.` . .. .`. ., `` -. .
.
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. .
.
, . . . . . ... .
.
f~!vo~ )3lsx 2 ~ ~ rj ~ r; ~> 5~cl/C~'11)/()02~
is secured to the manifold p.ipe 20 mi-lway along its length.
In use, as the equipment is dragged ~.long an ocea~.
bottom 26, water under pressure is supplied from a pump on the towing vessel (or on the equipment itself) to th~
inlet pipe 24 and manifold 20 t:o cause jets of water to issue from the nozzles 22. The nozzles ~2 are angled to cause the water jets to impinge on the ocPan bottom 26 in front of the lower front edge portion 18 of the bag 16 so as to force ~callops off the ocean bottom into or at least into the path of the open end of the bag 16. Figure 2 shows a scallop 28 being forced off the ocPan bottom 26 by a jet of water from a nozzle 22 into the path of the bag l6, Since the water jets in accordance with the invention enable more scallops to be caught per pass of the equipment over a given area of ocean bottom than is the case with previously known equipment of the sweep chain type, there are fewer uncaught scallops to be damaged by passage of the equipment over them. Also, as mentioned earlier, damage to uncaught scallops is also lessened becausa P~wer passes are required to catch a desired percentage of scallops in the area.
Some times, a scallop will sense the approach of the equipment and will attempt to "swim" away. Such scallops will probably remain in the path of the open end of the bag 16 and therefore be caught, as indicated in Figure 2 by scallops 30. This also applies of course to ~UBSTI~UTE SHEET
.
~"
.
.~ . , , ~ . .
.
~VO~ )31~ 2 0 ~ 5 2 5 ~ r~cr/cA~)o/o~27s f ', r, prior art equipment of the sweep chain kind.
The no~zle 22 may advantageously be arranged to cause the water jets to form a diffuse spray. It has been found that a water pressure in the range of 40 to 60 psi is suitable ~or this purpose.
Other embodiments and advantages of the invention will be readily apparent to a person skilled in the art.
S3JB~TITUTE SHEET
.. . . . ... . . .
, :..... . . . .. .. . . . .
,. . . .
.
. .
, . . . . ~ ~.
~, .
i . , . . ` .
ocean bottom is smooth soft sand or mud free of rocks.
This is usually not the case in the off-shore fishing areas of Canada and the United States o~ America, where most ocean bottoms comprise hard packed sand, a sand/gravel composite and/or rocks of varying sizes. such hard bottoms cause the teeth to be broken o~f. With such hard bottoms therefore, it is usual to use the less efficient sweep equipment.
Unfortunately, both types of equipment caùse unacceptably high destruction of uncaught scallops, namely as a result of the collecting bag being dragged over uncaught scallops. This is particularly serious because the usual practice is to make several passes over the same area, i.e. to drag the e~uipment several times along the same stretch of ocean floort to increase the catch from the area concerned.
There is therefore a need ~or improved scallop fishing equipment o~ the sweep kind which catches scallops more efficiently than known equipment of this kind.
According to the present invention, water jets are used to cause stationary scallups to be lifted from the ocean bottom ~nto ~he path of the open mouth o~ the collecting bag so as to be caught thereby as the equipment is dragged along an ocean bottom. Such jets may be provided by nozzles mounted on a transverse manifold pipe carried by the frame and supplied with water under pressure by a pump mounted on the towing vessel or the "
5~BsllTuTE SHEE~i , . ' ;':, , ' . ' ' ~ '' ' ` , , ` ' ' ` `
,~ . . .
vo ~ )3l:~x ~ ~3 !; ~ ~ J .3 1~cr/c~)o f fra~e and appropriately connected to the manifold.
Advant~geously, the water jets form a diffuse spray.
The invention substantially increases the efficiency of the sweep chain type of scallop fishing equipmellt. This type of equipment can therefore be used efficiently with soft as well as hard ocean bottoms.
There is less destruction of uncaught scallops because more scallops are caught in a single pass over a given area. ~lso, fewer passes are required to catc~l the same number of scallops compared to prior art equipment.
The present invention is substantially different from known hydraulic dredging equipment which is used to catch clams. As mentioned earlier, clams are buried or partly buried in sand or mud, and the hydraulic dredging equipment is used to dig clams out of the ocean bottom with the aid of water jets and a carrier ramp assembly set to travel at a depth of several inches below the ocean bottom to scoop up clams from a trough created by the water jets. This is in contrast to the present invention in which water jets are used to cause scallops to be lifted upwardly from the ocean bed so as to pass into the mouth of the aollecting bag.
One embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings, of which: -Figure 1 is a diagrammatic plan view of scallopfishing equipment in accordance with the invention, and SUBSTITUTE SHEET
. .
, .
~V(~9l/~3l~ ,3~ CI/CA90/~J(3~7B ~-(~, -- 4 ~
Figure 2 is a diagrammatic side YieW of the equipment showing how scallops are caught as the equipment is dragged along ~n ocean bottom.
Referring to the drawings, scallop fishing equipment includes an upright rectangular open frame ~2 with a towing bridle 14 secured to the front thereof. The chain link bag 16 has its open end secured to the periphery of the frame 12, which accordingly maintains the bag 16 in an open configuration. When dragged along an ocean bottom, the lower edge portion 18 of the open end o~
the ~ag 16 assumes a rearwardly-extending forwardly concavely curved configuration, as indicated in Figure 1~
As so far described, the scallop fishing equipment is conventional. In use, the eguipment is dragged along an ocean bottom by a towing vessel so that some of the scallops on th~ ocean bottom pass over the lower front edge portion 18 o~ ~he bag 16 and are therefore caughtO
Some scallops may also be caught "in flight" while they are in motion above the ocean bottom and in the path of the open mouth o~ the bag 16. ~s indicated earlier, the frame 12 and bag 16 will pass over and probably damage or kill many uncaught scallops.
In accordance with the invention, a manifold pipe is secured transversely across the ~rame 12 at a position slightly below mid-height level of the frame 12.
A series o~ rea~ardly and downwardly connected nozæles 22 are fitted ko the manifold pipe 20, and an inlet pipe 24 SlL)BSTITUTE S~ET
.` . .. .`. ., `` -. .
.
`
.
`
. .
.
, . . . . . ... .
.
f~!vo~ )3lsx 2 ~ ~ rj ~ r; ~> 5~cl/C~'11)/()02~
is secured to the manifold p.ipe 20 mi-lway along its length.
In use, as the equipment is dragged ~.long an ocea~.
bottom 26, water under pressure is supplied from a pump on the towing vessel (or on the equipment itself) to th~
inlet pipe 24 and manifold 20 t:o cause jets of water to issue from the nozzles 22. The nozzles ~2 are angled to cause the water jets to impinge on the ocPan bottom 26 in front of the lower front edge portion 18 of the bag 16 so as to force ~callops off the ocean bottom into or at least into the path of the open end of the bag 16. Figure 2 shows a scallop 28 being forced off the ocPan bottom 26 by a jet of water from a nozzle 22 into the path of the bag l6, Since the water jets in accordance with the invention enable more scallops to be caught per pass of the equipment over a given area of ocean bottom than is the case with previously known equipment of the sweep chain type, there are fewer uncaught scallops to be damaged by passage of the equipment over them. Also, as mentioned earlier, damage to uncaught scallops is also lessened becausa P~wer passes are required to catch a desired percentage of scallops in the area.
Some times, a scallop will sense the approach of the equipment and will attempt to "swim" away. Such scallops will probably remain in the path of the open end of the bag 16 and therefore be caught, as indicated in Figure 2 by scallops 30. This also applies of course to ~UBSTI~UTE SHEET
.
~"
.
.~ . , , ~ . .
.
~VO~ )31~ 2 0 ~ 5 2 5 ~ r~cr/cA~)o/o~27s f ', r, prior art equipment of the sweep chain kind.
The no~zle 22 may advantageously be arranged to cause the water jets to form a diffuse spray. It has been found that a water pressure in the range of 40 to 60 psi is suitable ~or this purpose.
Other embodiments and advantages of the invention will be readily apparent to a person skilled in the art.
S3JB~TITUTE SHEET
.. . . . ... . . .
, :..... . . . .. .. . . . .
,. . . .
.
. .
, . . . . ~ ~.
~, .
i . , . . ` .
Claims (9)
1. An apparatus for scallop fishing comprising:
a frame for towing behind a vessel;
a bag connected to the frame for receiving scallops, having a mouth wherein part of the mouth is adapted for dragging along an ocean floor and behind the frame and the remainder of the mouth is adapted to maintain the bag open above the ocean floor;
water jets for applying a water spray to disturb the ocean floor ahead of the bag opening; and pump means for delivering water under pressure to the water jets.
a frame for towing behind a vessel;
a bag connected to the frame for receiving scallops, having a mouth wherein part of the mouth is adapted for dragging along an ocean floor and behind the frame and the remainder of the mouth is adapted to maintain the bag open above the ocean floor;
water jets for applying a water spray to disturb the ocean floor ahead of the bag opening; and pump means for delivering water under pressure to the water jets.
2. An apparatus as claimed in claim 1 wherein the water jets comprise a manifold mounted substantially horizontally onto the frame and having a plurality of downwardly and rearwardly directed nozzles.
3. An apparatus as claimed in claim 2 wherein the nozzles are adapted to produce a diffuse spray.
4. An apparatus as claimed in claim 3 wherein the pump means comprises a pump mounted on the vessel having a high pressure exhaust connected to a pressure hose connected to the manifold.
5. An apparatus as claimed in claim 4 wherein the frame has a first end for receiving a tow means and extend substantially horizontal and a second end having an inverted U-shaped member extending upwardly for receiving the bag.
6. An apparatus is claimed in claim 5 wherein the perimeter of the bag mouth exceeds the length of the U-shaped member and the remainder of the bag mouth is joined to the U-shaped member.
7. An apparatus as claimed in claim 6 wherein the pump delivers water in the range of 40 to 60 pounds per square inch.
8. An apparatus as claimed in claim 7 wherein the bag is made from a chain link material.
9 An apparatus as claimed in claim 5 wherein the tow means is a length of rode connected between the vessel and the frame.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB898919951A GB8919951D0 (en) | 1989-09-04 | 1989-09-04 | Scallop fishing equipment |
| GB8919951.7 | 1989-09-04 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2065253A1 true CA2065253A1 (en) | 1991-03-05 |
Family
ID=10662494
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2065253 Abandoned CA2065253A1 (en) | 1989-09-04 | 1990-08-30 | Scallop fishing equipment |
Country Status (4)
| Country | Link |
|---|---|
| AU (1) | AU6293190A (en) |
| CA (1) | CA2065253A1 (en) |
| GB (1) | GB8919951D0 (en) |
| WO (1) | WO1991003158A1 (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4424238C2 (en) * | 1994-07-09 | 1996-05-23 | Meyer Haiko Gmbh & Co Kg | Method and device for fishing flatfish or the like |
| NL1020451C2 (en) * | 2002-04-22 | 2003-10-23 | Tno | Method and device for collecting animals in or on a water bottom. |
| KR20020062711A (en) * | 2002-06-21 | 2002-07-29 | 최순석 | Collector that can collect dog money efficiently. |
| NL1034219C2 (en) * | 2007-08-01 | 2010-09-22 | Anno Maria Galama | FISHING GEAR WITH POWERED GUIDANCE BODIES. |
| GB0916383D0 (en) * | 2009-09-18 | 2009-10-28 | Oban Scallop Gear Ltd | Apparatus for harvesting shellfish |
| CN102812935A (en) * | 2012-09-04 | 2012-12-12 | 阳江市高级技工学校 | Mudflat shellfish collecting device |
| AU2017202948A1 (en) * | 2017-03-02 | 2018-09-20 | Hotrocks Limited | Apparatus and method for gathering shellfish |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR1591299A (en) * | 1967-11-06 | 1970-04-27 | ||
| US3862502A (en) * | 1973-10-19 | 1975-01-28 | Ben Young | Clam harvester |
| NL8403029A (en) * | 1984-10-04 | 1986-05-01 | Johan Van Zuydam | Flat fish and crustacean catching method - uses compressed air nozzles to agitate sea-bed and flush fish |
-
1989
- 1989-09-04 GB GB898919951A patent/GB8919951D0/en active Pending
-
1990
- 1990-08-30 WO PCT/CA1990/000278 patent/WO1991003158A1/en active Application Filing
- 1990-08-30 AU AU62931/90A patent/AU6293190A/en not_active Abandoned
- 1990-08-30 CA CA 2065253 patent/CA2065253A1/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| WO1991003158A1 (en) | 1991-03-21 |
| GB8919951D0 (en) | 1989-10-18 |
| AU6293190A (en) | 1991-04-08 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Dead |