The fishing industry is taking action to show that they have responsible fishing practices.
Shark fishers initiated the closure of inshore Victorian coastal waters to a distance of three nautical miles (5.4 kilometres) to targeted shark fishing as a measure to protect young pups and breeding adults.
A group of Bay and Inlet fishers (Victorian Bays and Inlets Fishermen's Association) developed an Environmental Management System (EMS) for their fishery. This EMS provides a systematic approach to recognising, assessing and mitigating environmental risks facing the fishery. VBIFA sought and received funding to employ respected fisheries scientist, Dr Pascale Baelde, to develop and implement the EMS.
Fishers in Corner Inlet use four-stroke outboard motors instead of two-stroke motors as these engines are more fuel-efficient, produce less emissions and leave no oil residue on the water. This measure was implemented as part of an environmental management plan overseen by the Corner Inlet Fisheries Habitat Association.
Commercial fishers support fishery related research. An industry supported study by the Marine and Freshwater Resources Institute found that 90% of fish captured and released from haul seine nets survive. The study confirms that Victorian bay and inlet fishers are using correct handling techniques such as bunting up in waist deep water and using dip nets to release discards unharmed to the water immediately.
The Rocklobster Fishery has implemented a code of practice for reducing whale entanglements. This code outlines the voluntary measures taken by Rocklobster fishers to reduce the risk of migrating whales becoming entangled in their pot ropes. This is a proactive response to ensure the fishery can continue to share the environment with increasing numbers of whales migrating along the coast.
At the behest of abalone fishers a total allowable catch (TAC) divided into individual transferable quotas (ITQ) was introduced in 1988. A conservative 1440 tonne TAC was set for conservation of stocks. The single biggest threat now to the fishery is illegal harvesting. More recently the industry negotiated a memorandum of understanding (MoU) with the government to address the serial depletion of abalone stocks at easily accessible sites.
Fishers catching wrasse raised concerns about increasing harvest levels in 1996. As a result a workshop was initiated that introduced specific management measures such as access licences and size limits to protect wrasse stocks.
During 1993 an arrangement was set up to give each Victorian eel fisher specific access to a maximum of three specific waters (rivers, lakes etc) based on their fishing history. This access provides fishers with more control over re-stocking and harvesting of eels ensuring sustainability.
The Australian seafood industry has a code of conduct that sets out principles and standards of behaviour for responsible practices to ensure effective conservation, management and development of living aquatic resources, with due respect for the ecosystem and biodiversity. The code is part of a series of initiatives by industry to ensure it operates in an ecologically sustainable manner. Many Victorian fisheries sectors have adopted aspects of this code into their own codes of practice specific for their fishery or region. These codes promote an understanding within the community of commercial fishing activities and provide a means for industry to address issues that may not be easily or practically regulated.
Fishing Methods
Harvesters are used to collect molluscs off the seabed. In Victoria scallops are harvested using a self-tipping mud dredge.
Design
The Australian mud dredge was designed in the early 1960s. The harvester is made of a rigid steel frame that is covered with uniform weldmesh. The opening of the mesh must be larger than 68mm in length by 44mm in width. The harvester must measure less than 336cm wide. They weigh about 500 kilograms out of water. Wide runners are added to the base of the harvester and help to lift it slightly off the seabed. A toothed bar is added to the front opening of the dredge. The teeth are about 5cm long and are set at 7cm intervals at a 40-degree angle. The teeth help to dig out the scallops from the seabed.
Operation
Boats travel out to areas where scallops are likely to be found. Once there, buoys are laid approximately one kilometre apart across the scallop bed. The vessel tows the harvester in between the buoys on the surface.
The harvester is lowered from the back of the boat into the ocean. Enough towing wire is let out from a single winch so that the harvester works along the seabed. The amount will depend on the depth of water. The dredge is usually towed at a speed of 3 knots. After a 10 to 30 minute tow the dredge is hauled. The dredge enters a tipper secured to the back of the boat and the catch is emptied onto a tray for sorting and packing into crates or bags. The dredge may be returned to the water for another tow.
Boats working in Bass Strait are generally about 18 meters in length. The engine requirements are between 225 and 450 brake horsepower and depend on the size of the vessel and the dredge.
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Pots are a type of trap. Pots work on the principle of attracting the target species, allowing for an easy entry and a difficult exit. There are many different designs for pots that are used across the world. In Victoria beehive shaped pots are used to catch southern rocklobsters and giant crabs.
Design
Beehive shaped pots were originally made using a wire frame with a covering of woven tea-tree sticks, the entrance being woven from cane. Now the pots are made with a steel frame and covered with wire mesh or netting and the entrance is a plastic funnel. Pots are typically 75 cm in diameter and weigh about 20 kg. The entrance of the pot is located at the top of the trap and animals are enticed to enter by the attraction to the bait. The pots are baited using whole fish (pilchards or mullet) or fish heads (Australian salmon, carp or wrasse) that attract rocklobsters. Rectangular gaps (25cm x 6cm) are fitted near the pots base and allow undersize rock lobsters to escape.
Operation
Suitable fishing areas are found using an echo sounder, sonar or Global Positioning System (GPS). A good deal of knowledge and skill is required to ensure a successful fishing trip. The pots are set singly with a line to the surface where it is supported by a float or buoy. The line to the surface is non-floating so that it is not in danger of being cut by passing vessels.
Pots are usually set mid afternoon and hauled in early the next day. This takes advantage of the increased night activity of rock lobsters. Pots are baited and pushed overboard followed by the line and float/buoy. Sufficient length of line is used taking into account the tide and current. When retrieving, the line and buoy are picked up with a hooked pole or grappling hook. The line is hauled in by an electrically driven line hauler over the side of the boat and lifted aboard. As each pot comes aboard the catch is removed and measured with undersize individuals being returned directly to the water. The pot is then rebaited and reset.
Rocklobsters are held in either wet-wells or tanks of circulating seawater keeping them alive until the boat returns to port. Fishing trips can be as short as one day when the boat goes out to pull the pots, resets them and returns to port or trips can be a weeklong.
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Purse seining involves searching and catching mobile schools of fish with a net with a closable bottom. This method is used to capture pilchards (Sardinops neopilchardus), sandy sprat (Hyperlophus vittatus), anchovy (Engraulis australis), and blue sprat (Spartelloides rebustus) in Port Phillip Bay and also in Bass Strait.
Design
A purse seine net is a long panel of netting. The detailed design of the net depends on the species targeted the water depth and the method of handling. Nets used are between 350 and 460 metres in length and about 36 metres deep. The net is designed to fish near the surface. The mesh size is small typically 12mm, although a small panel at the top and bottom of the net has larger mesh sizes, this reduces the drag of the net through the water. The float line with closely spaced polyurethane floats runs along the top of the net. The floats hold the top of the net at the surface during setting and hauling. The footrope has a leaden core to sink the netting to make a wall. The purse line runs through 20cm metal rings connected by short drop lines from the footrope.
Operation
Schools of suitable fish are located using birds feeding on a school of fish and electronics like sonar and echo sounders. When the vessel nears the school visual sighting is used to determine the species and size of fish. The vessel then manoeuvres depending on wind and tide so that it can pay out the net and complete a circle around the fish.
When setting the net passes over the stern or back of the vessel. The end of the net is held in position with a large weight with a buoy at the surface. The vessel then steams in a complete circle around the school paying out the net.
When the vessel reaches it's starting point the ends of the net are brought together completing the circle. The purse line is then hauled in using a winch and stored in a tub. When all of the rings are hauled in they are transferred to a holding rack. The net, float line, footrope and purse rings are then hauled in from one end passing over a hydraulically powered v-sheave called a power block. The net is then stowed away for the next set. Hauling continues until the fish are gathered in the remaining portion of the net, called the bunt, close to the side of the vessel.
The fish are removed from the bunt by brailing. The brailer is a large scoop net handled either by hand or by overhead hydraulic boom. The fish are emptied into plastic fish bins or bulk storage bins on board the vessel. Ice is added to the bins to keep the fish fresh for humans or pet food. Salt is added if the fish are going to be used for bait. The complete setting and hauling operation takes about one hour.
Vessels used in Victoria range from 10 to 20 metres in length and are powered by on-board diesel engines, typically about 210 horsepower.
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Diving is a traditional means of collecting molluscs. Divers collect abalone and sea urchins (Heliocidaris erthrogramma) in Victoria.
Design
Divers wear 7mm or 9mm neoprene wetsuits. The wetsuits protect the diver from exposure of low temperatures and provide extra buoyancy. To offset the buoyancy, divers wear lead weight belts to help them reach the seabed. Compressed air is supplied to the diver through a plastic hose from the support boat. The diver uses the air as required by breathing in and out through a regulator. This is called hookah diving. Divers can also carry a small air tank for emergencies. Divers also wear facemasks and flippers.
Operation
Abalones are searched for over rocky reef areas. Once found they are lifted off the reef with a rounded spatula-like tool and placed in a mesh bag. Sea urchins are picked up using long metal tongs. As the catch bag fills with abalone the diver inflates a small bag attached to the side of the catch bag to make it easier to lift. When the bag is full the diver fully inflates the side bag, sending the catch to the surface. The crewmember onboard the support boat measures and packs the catch into sealed bins.
Support boats are modern high-speed boats. They measure between 5 and 10 meters in length and are able to be towed on trailers. The boats are powered by twin outboard motors with a total power of 230 to 450 horsepower.
The vessel with the diver working below is not anchored but is allowed to drift. This allows the diver to cover more area without the need to surface as often. Divers work in water depths from 2 to 40 metres.
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A mesh net is a panel of netting that is held vertically in the water. They are also called gill nets. This is probably one of the oldest forms of net fishing. In Victoria mesh nets are used to catch inshore fish like rock flathead and black bream in Gippsland Lakes and offshore to catch sharks.
Design
The panel of netting has a rope along the top to which floats are attached. Another rope runs along the bottom to which lead weights are attached. Nets used in bays and inlets are up to 2m deep and can be up to 2500 meters long depending on which bay you are working in. Shark nets are 20 meshes deep and some fishers use eight nets with a combined total length of 4200 meters.
Depending on the mesh size and the way the netting is hung (constructed), will determine what size and species of fish is caught. Generally a hanging ratio of 0.5 is used. The mesh size must be matched to the fish's body shape and girth, so the mesh size and shape changes depending on the species and size range being targeted. Mesh sizes for black bream is 98mm, 50mm for whiting, 65mm for rock flathead and 152mm for shark. The mesh material is light-weight, usually multi-monofilament (monofilament for sharks) so that the fish does not see or sense the net before it is caught.
Operation
Mesh net fishing is a passive form of fishing. The number of fish caught depends on the location that the net is placed. Knowledge of fish movements is needed so that the net is set in the correct position.
The net is secured to the bottom using an anchor or lead weight. A marker buoy is used so that the net can be easily found. The net is then let out over the side or back of the boat as it moves along. The net is then left to soak for a length of time, between 30minutes and six hours, depending on local conditions. The boat generally stays with the fishing gear although some fishers prefer to leave the gear and return a short time later.
The net can be set in a straight line or depending on the current and bottom type, in curves and hook shapes.
Hauling the net onboard is done manually from the side of the boat in bays and inlets. On shark boats the net is hauled in over the bow (front) of the boat using a free-running roller. As the net is hauled in the fish are unmeshed sorted and placed in plastic storage bins.
The mesh size of a net specifically chooses the size of the fish that is caught. Most fish are caught by their gills as they attempt to free themselves from the net. Other sized fish may also be caught by accident as they fight to get through the net, or are snagged by their spines or protruding fins.
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Trawling involves towing a net along the seabed and herding fish into the net where they are held. Trawling is also called stern trawling, otter trawling, bottom or demersal trawling. Trawling is one of the more widely used fishing methods in Australia. It is used in the South East Fishery to catch deepwater fish.
Design
The modern trawl net is basically shaped like a funnel and is towed through the water along the seabed to scoop up fish on or near the bottom. The opening at the start of the net, called the mouth, has large round plastic floats on the top rope and rubber disks and heavy metal chains on the bottom rope. The net has wing ends that reach forward of the mouth. These panels of netting have large mesh sizes to reduce the drag of the net. As fish move through the net the mesh size gets smaller, until it reaches the smallest mesh size at the end, called the codend. The size of the mesh in the codend determines the final size of the fish caught. Small fish are able to escape through the mesh, leaving the larger marketable fish in the net. Typically the codend mesh size is 90mm.
The net is attached to the boat via long steel cables. The cable that attaches the boat to the otter boards is called the warp. The length of this cable is determined by the water depth, typically a ratio of 4 metres of cable to every 1 metre of water. The otter board is a piece of heavy metal that is used to spread the net open. The cable that attaches the otter board to the net is called the sweep. This cable runs along the seabed and helps to herd the fish towards the mouth of the net.
The design of the fishing gear is suited to the species targeted, and the type of seabed to be encountered.
Operation
Vessels operating in the South East Fishery use the stern trawling fishing method. This means the boat sets and tows the net from the back or stern of the vessel.
Suitable fishing grounds are located using knowledge of the target fish's behaviour and finding suitable seabed bottom using an echosounder. The net is unwound from a storage drum and set behind the boat. The sweep cable is wound out and then the otter boards are attached and lowered into the water, with the warp cable attached. All the gear is then towed along the seabed at a low speed of 2-3 knots (4-5km/hr) usually for between one and three hours. Hauling is the reverse of setting.
The fish caught in the net are retained the in codend. This is usually lifted aboard using a hydraulic winch system. The fish are released from the codend by untying the special knot in the codend rope and dumped onto the deck area.
Crewmembers sort the catch into species and move the catch into below deck storage holds. The storage holds are refrigerated to keep the catch cold; ice is also used. Some vessels use refrigerated seawater tanks to place the catch into.
Trawl vessels range in length from 15 to 32 metres and are powered by on-board diesel engines. A typical fishing trip lasts between three and seven days.
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Longline fishing is one of the most environmentally friendly and cleanest catching methods. Longlining is a static hook and line fishing method. The gear is rigged to suit the species targeted and the area being fished. Longlines are used to catch sharks and blue-eye trevalla in offshore waters and snapper in bays and inshore coastal waters.
Design
Longlines involve setting out a length of line, often several kilometres long, to which short lengths of line carrying baited hooks are attached at intervals. The fish are attracted to the bait, then hooked and held by the mouth until they are brought onboard the vessel.
Longlines can be set horizontally just below the surface or along the seabed and vertically. Vertically set longlines are called drop-lines or trotlines.
Large brightly coloured floats are used to mark the position of the fishing on the surface. These floats may also have flags, called Dan buoys, to aid in relocating the gear. The gear may also have reflector beacons and flashing lights to aid retrieval at night.
Where the fishing gear is designed to catch bottom living fish the gear will be anchored to the seabed using heavy weights or anchors.
Hooks and bait used are particularly selective in terms of species and size.
Operation
To begin setting a longline, the first buoy (and anchor) is put overboard. The vessel travels along the desired track while the line runs out over the stern. Tubs containing baited hooks around the rim are set out in series. The hooks are attached to the mainline using snap-on devices; a bit like safety pins. The hooks are attached at regular intervals. Longlines used in Port Phillip Bay have a maximum of 200 hooks and are spaced about every 10 metres. Drop-lines only have hooks attached to the lower section.
When all the gear has been set, the boat will travel back to the start and will then wait for the hooks to have soaked for the required length of time. In bays this is one hour.
When ready to haul the gear, the vessel approaches the leeward (sheltered) end of the set and retrieves the first marker buoy, anchor and end of mainline. The line is hauled in over a roller or side of the vessel. The branch lines are unclipped and if a fish is attached it is brought aboard using a landing net or gaff. The hook is removed from the fish's mouth and placed in storage bins. If hooks are lost they are replaced immediately before storing. The branch lines and hooks are placed on storage racks, while the mainline is coiled into a large tub.
Small longline operations are labour intensive. Large operations are often mechanised.
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Danish seining is a bottom fishing method that was developed by a Danish fisherman around 1850. The fisher changed the gear and created a method of using a beach seine away from the beach using a powered boat. In Australia the largest Danish seine fleet operates out of Lakes Entrance, Victoria and targets flathead (Platycephalidae) and whiting (Sillaginidae).
Design
The arrangement of a Danish seine net is similar to a beach seine. It has long wing ends, up to 20 meters in length, which taper to a codend, where the fish are held. Attached to the wings are long (2000 meters) hauling ropes that are 22mm thick. Wire cable is used for both the headline and footrope. Medium 20cm floats are attached to the headline. The footrope has short lengths of chain attached to keep the wing ends on the bottom and bobbins (round rubber disks) made from old tyres to roll the gear along the bottom. A metal triangular towing sled is used as the towing point.
Operation
A large float and Dan buoy are dropped over the side of the boat with the start of the hauling ropes attached. The boat then travels along one side of a triangle letting out about 1200 meters of rope. The boat then changes direction, about 60 degrees, and begins the second leg. During the second leg the remaining length of rope (800 meters) is let out along with the wing end, codend, other wing end, and a further 800 meters of rope. The boat then changes direction for a second time and begins the third leg setting out the remaining amount of rope heading towards the starting point. The setting operation takes about 20 minutes.
The boat will then pick up the float and Dan buoy and begin towing the gear. Towing brings the hauling ropes and wing ends together, herding any fish that are in between towards the net. Towing is done at a low speed of 2 knots for about 40 minutes or until the ropes at the back of the boat are almost parallel.
Hauling in the two ends of rope then starts. A hydraulic winch with tension spring is used to retrieve the rope. The rope is coiled into storage holds. When the towing sleds are brought on board the rest of the net is hauled in over a hydraulic power block mounted on the back of the boat. A rope is then tied around the top of the codend and the codend is brought around to the side of the boat. A hydraulic winch on a boom is used to lift the codend over the side of the boat where is it positioned over the sorting tray. The rope closing the codend is released and the catch is emptied onto the sorting tray. Crewmembers then sort though the catch placing targeted species in fish boxes and returning the unwanted portion of the catch back to sea through large scuppers (holes along the side of the boat at deck level). The deck is hosed clean and the net is reset. The catch is placed in the cool room below deck with ice.
Vessels used by Victorian fishers range in size from 10 to 25 metres in length and are powered by on-board diesel engines.
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Squid jigging is a form of hook and line fishing. Jigging is the most important fishing method for catching squid. The Japanese have extensively developed the technology and it can be used on small or large vessels. Victorian boats use mechanised jig machines to catch predominantly Gould's squid and occasionally southern calamari.
Design
The line with up to 30 jigs attached is stored on an oval shaped spool. The plastic jigs are cigar shaped and have two rings of barbless hooks at one end. The line has a breaking strain of 13.6 kg (30lb). A lead weight is added to the end of the line. This helps to keep the line vertical while being wound up and down. The jigging machines used are automatic. Each machine has two spools fitted about one metre apart with between 4 and 6 machines fitted on a boat depending on its size.
Operation
Jigging in Victoria is a night fishing method. Boats (average length 14 metres) set out from shore late in the afternoon to reach the fishing ground by dusk. Parachute sea anchors are set from the boat to reduce the pitch and roll of the ocean to produce a more stable working platform. It also reduces the drift of the vessel allowing it to stay fishing over a congregation longer.
Powerful electric lights are positioned along the vessel to attract the small fish and crustaceans that squid feed on. The brighter the luminescence the more prey that is attracted and the more squid that can be caught. The brightness of the light is influenced by the phase of the moon. With the new moon producing the better catches. The squid congregate in the shadowed area next to the vessel and dart into the lit area to feed.
The line is lowered over the side of the vessel to the pre-set depth (set by key pad on the jig machines computer) before being wound up again. The irregular rotation of the spool as the line is wound creates the jigging action. As the lures move through the water it simulates prey and is attacked by the squid, which is then impaled on one or more of the hooks. Squid are hauled over the front roller and flicked onto a wire mesh screen attached to the side of the boat. The screen is sloped so that the squid will make their way into the deck. The crew picks up the squid from the deck and places them in 33kg plastic fish bins. As the bins are filled a layer of ice is added and the bins are stored on board until the boat returns to port in the morning.
Fishing trips are usually overnight although if the squid are located a long distance off shore then fishing trips may be two or three days.
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Fyke nets are a type of trap net. They are relatively small and lightweight compared to other types of fishing gear. As a trap their effectiveness depends on preventing the fish from leaving the trap once they have been enticed to enter it.
Harvesting of eels is done using fyke nets. Most rivers, creeks, lakes, dams and swamps on public land south of the Great Dividing Range are open to commercial eel fishing.
Design
A fyke net is a collapsible conical net. The aluminium or wooden hoops provide the frame for the netting. The nets are typically between 5 and 11 metres long with panels of netting called wings out in front adding and extra 5 to 30 metres in length. Fyke nets can have one, two or three wings. The entrance is D-shaped in smaller nets with the larger nets having a rectangular entrance. Internal funnels are used to direct the eels inside. The final funnel exit is collapsed so that the eels are trapped and retained in the final compartment of the net. The mesh size of the netting is between 2.5 cm and 3.2 cm. Floats and lead weights are added to the wings.
Installing plastic 101.5 cm grids prevents accidental catch of wildlife, as only eels are able to pass through the grid.
Operation
Fyke nets are staked in waters where eels are known to travel through. Most of the harvesting is done during the period when the eels are changing appearance for their migration to sea. For short-finned eels this fishing period is between January and May.
Fyke nets must be checked every 48 hours to release bycatch if any and remove any eels caught. Installing grids at the entrance of the trap reduces bycatch. The setting of a portion of the net above water ensures that air-breathing wildlife can be released with minimal harm.
The eels caught in the nets are emptied into net holding bags on the boat. They are then transported in live holding tanks on the back of a four-wheel drive vehicle. At the processing plant the eels are placed into live holding tanks to clean out their digestion system before processing.
The boats used are small between 3.5 and 4.5 meters in length, powered by an outboard motor. The boats are made from aluminium and those working in shallow waters are flat bottomed.
In addition to harvesting of wild stocks, small eels are transported to culture lakes where they grow and develop under natural conditions. Harvesting of short-fin cultured eels occurs during August to January using fyke nets.
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Hand line fishing is one of the simplest methods of fishing with baited hooks being attached to a line. This fishing method is also one of the oldest with hooks made out of animal bone being used in prehistoric times.
Both commercial and recreational fishers use this method of fishing. Hand lines are used by Victorian fishers to target blue throat wrasse and saddled wrasse.
Design
Hand line gear consists quite simply of one or more baited hooks attached to a line. If needed weights are added to help the gear sink to the desired depth. The line is wound onto a plastic reel for use of handling and for storage. Some fishers prefer to use a reel that is attached to a fishing rod. This slows down the rate that the line is taken by the fish by adding a brake or drag system.
Hooks are particularly selective in terms of species and size. Hook design and size is important to determine the size of the fish caught. The gap between the point and the shank determines the size of the fish caught. Modern hooks are made from stainless steel. Hooks used to catch wrasse are J-shaped.
Operation
Boats anchor in position near a reef known to have wrasse. The crew on the boat tend the lines. Up to six lines can be used with no more than 3 hooks per line. It is common that one crew member only looks after two lines. As soon as a fish is hooked the line is reeled in and the hook removed from the fish's mouth. The wrasse is measured and if over the legal minimum size of 28cms the wrasse is placed into a live holding tank on board the boat. The hook is then rebaited and returned to the ocean.
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