Major Research Findings

Standard designs of mechanized fishing crafts

Twelve standard designs of wooden fishing boats in the size range of 7.67 to 15.24 m were developed and introduced which gave a major fillip to the mechanization programme of Indian fisheries.

 

Aluminium alloy sheathing for wooden fishing vessels

Aluminium-magnesium alloy sheathing was developed as a cost effective substitute for copper sheathing for wooden hulls as protection against marine borers.

 

Cathodic protection

Mercury-free ternary aluminium anodes were developed for cathodic protection of steel fishing vessels against marine corrosion.

 

New substitutes for propeller material

pheroidal graphite cast iron with nickel (21-24 %) material as substitute for conventional manganese-bronze for propellers of fishing boats, resulting in cost savings of 25-30%.

 

Marine anti-corrosive paints

Cheaper anticorrosive paints were developed incorporating cashew nut shell liquid resin and zinc chromate.

 

Marine antifouling paint

Superior cost-effective antifouling paint formulations incorporating cuprous oxide and modified indigenous resins were developed for protection against fouling, in fishing boats.

 

Chemical wood preservatives

Chemical wood preservatives such as arsenic creosote, copper creosote and creoscor were developed for protection of traditional crafts against bio-deterioration.

 

Indigenous resin based protective coatings for wooden crafts

Protective coatings based on indigenously produced natural resins such as Andaman damar (Canarium euphyllum), black damar (Canarium strictum), rock damar (Hopea robusta), white damar (Vateria indica) as substitute for imported damar battu (family: Dipterocarpaceae) extensively used for protection of traditional wooden crafts in Maharashtra and Gujarat.

 

Ferrocement for boat building

Economic feasibility of ferrocement as substitute material for steel and wood for construction of fishing boats of 12-17 m length class.

 

Rubber wood canoes

The rubber wood, which comes as a waste from rubber plantations, can be efficiently utilized after upgrading by chemical preservative treatment. The Central Institute of Fisheries Technology, Cochin has successfully used treated rubber wood as alternative material for construction of traditional fishing craft. Treated rubber wood canoe can be further protected using fibre glass reinforced plastic (FRP) sheathing

 

Poma / other low cost wood canoes with FRP sheathing for NEH region

• Netting, netting yarn and netting twine for fishing gear fabrication
• Standardization of netting, netting yarn, netting twine, floats and hooks for fishery purposes.

 

Combination wire rope

Standardization of combination wire rope for deep sea trawl gear leading to import substitution through indigenous manufacture.

 

Improved lobster trap

Improved and durable lobster traps in substitute for traditional traps of short life span and low efficiency for harvesting of spiny lobster. Design: 700 x 550 x 400 mm size. It has a mild steel rod frame mounted with 25 mm square welded mesh, plastic coated for corrosion protection

 

Pots, gill nets and lift net for crabs

Crab pots, gill nets and crab lift net for catching crabs in live and undamaged condition.

 

Mini-trawl for traditional motorized crafts

A mini-trawl for operation from traditional crafts powered by outboard motors of 8-15 hp, for shallow water shrimp trawling. Design: 12.77 m mini-trawl

 

Mini-purse seine

A purse seine for operation from traditional plank built canoes (Thangu vallom) powered by outboard motors, for efficient harvesting of pelagic shoaling fishes.

 

Improved dol nets

Improved dol net, which is a fixed bag net operated for Bombay duck (Harpodon nehereus) in Gujarat and Maharashtra, with better size selection properties and design permitting fabrication from ready-made netting

 

Long wing trawl

Specially designed trawl for shrimp trawling with low vertical opening and extra long wings on either side to facilitate sweeping of wider horizontal area along the sea bed to increase the catch.
Designs :17.0 m and 32.0 m long wing trawls.

 

Bulged belly trawl

Bulged belly trawl has relatively high vertical opening compared to conventional shrimp trawl, to improve the catch of finfishes by about 30 % without compromising on shrimp catching abilities.
Designs: 17.0 m, 20.0 m, 25.0 m, 32.0 m bulged belly trawls.

 

High opening trawl

In high opening trawls, vertical opening of the trawl is increased by innovative design improvements, facilitating capture of demersal as well as off-bottom resources.
Designs: 17.0 m, 25.0 m and 32.0 m six seam and 25.0 m eight panel high opening trawls.

 

Large mesh trawl

Relatively large meshes are incorporated in the forepart of trawl resulting in significant reduction in trawl resistance, making use of the herding effect of large meshes on fin fishes. The reduced drag permits greater trawling speed and/or operation of an optimum sized trawl. Designs: 25.0 m, 32.0 m and 40.0 m large mesh trawls

 

Rope trawl

In rope trawl, the front trawl sections are replaced by ropes which as in the case of large mesh demersal trawl, results in reduction of trawl resistance. Fin fishes are retained due to the herding effect of ropes. The reduced drag permits greater trawling speed and/or operation of a larger trawl with the available installed engine power. Designs: 35.0 m rope trawl.

 

Sheer devices for trawls

Otter boards

Otter boards are sheer devices used in trawls for keeping the trawl mouth horizontally open. Designs: Different sizes of flat rectangular boards of wood and steel construction, V-form steel otter boards and high aspect ratio vertically cambered otter boards for small mechanized fleet.

 

Flexible headline lifting devices for trawls

Sail kite and double walled flexible float as advantageous substitutes for traditional hard plastic floats and rigid kites.

 

Purse seine

Purse seines for catching pelagic shoaling fishes such as sardine and mackerel, from small mechanized vessels.

 

Long lines

Long line for sharks using indigenous hooks.

 

Troll lines

Troll lines for predatory fishes such as Spanish mackerel and barracuda, using buffalo horn, stainless steel, spoon and fish head jigs

 

Gill nets

Marine gill nets optimized for catching sardine, mackerel, Spanish mackerel, pomfret and hilsa, in terms of material and mesh size. Colour- optimized gill nets for hilsa.

 

Fishing gear for inland fisheries

• Gill nets
• Trammel nets
• Shore seines
• Monolines
• Trawls

 

High speed demersal trawls

Deep sea trawls developed for commercial harvesting of fast swimming, low density demersal resources in the depth range of 50 - 500 m depth, in the Indian EEZ.
Designs: 41.0 m HSDT-I, 38.0 m HSDT-II and 38.25 m HSDT-III

 

Trawls for deep sea operations in Indian EEZ

Bobbin trawl

Two-panel deep sea demersal trawl suitable for operation in the rough bottom conditions, in Indian EEZ.
Design: 32.0 m Bobbin trawl

 

Hybrid trawl

Multi-purpose hybrid trawl for cephalopod and demersal finfish resources.
Design: 38.0 m multi-purpose hybrid trawl.

 

High opening trawl

Two-panel trawl with high vertical opening suitable for harvesting demersal and off bottom resources. Design: 50.0 m high opening trawl.

 

Large mesh semi-pelagic trawls

Trawls incorporating large meshes for reducing drag and fuel consumption, for harvesting semi-pelagic resources.
Design: 33.7 m. large mesh semi-pelagic trawl,

CIFT Semi-pelagic trawl system (CIFT-SPTS) 18 m.
18 m. CIFT-SPTS with low impact on benthic biota with exchangeable contends for harvesting non-shrimp trawl resources.

 

Sampling gear for resource assessment studies

The necessity for developing standard and calibrated sampling gears for resource assessment studies has been a long felt need. 38.0 m HSDT-II crustacean and finfish versions have been identified as suitable for adoption for demersal finfish and crustacean sampling, respectively, during stock assessment studies.

 

Harvesting techniques for Antarctic krill

Acoustic detection and aimed midwater trawling techniques for Antarctic krill (Euphausia superba) have been developed, during First Indian Antarctic Krill Expedition (FIKEX) 1995-1996.

 

Selectivity of fishing gears

Information on fishing gear selectivity is important in biological investigations, fish stock assessment, fisheries management and fishing gear design & development. Selectivity characteristics such as mean selection length, selection range, selection factor and selection curve of square mesh and diamond mesh with respect to demersal catch components have been determined through covered codend experiments.

 

Bycatch Reduction Devices

BRDs are devices used to minimize the catch of non-targeted organisms during trawling. Benefits of BRDs are

• Reduction in impact of trawling on non-targeted marine resources.
• Reduction in damage to prawns due to absence of large animals in codend.
• Shorter sorting time.
• Longer tow time and
• Lower fuel costs due to reduced net drag. BRDs such as rigid grid devices, fish eye, radial escapement device, are being optimized for small-scale mechanised trawling industry.
• Oval rigid grid BRD, Fish eye, Big eye, Sieve net are recommended for shrimp trawls

 

Juvenile Fish Excluder cum Shrimp Sorting Device (JFE-SSD)

Trawl fishermen in India and other tropical fisheries depend on both finfish catches and shrimp catches to keep the commercial operations economically viable. CIFT has developed a unique solution for this in developing Juvenile Fish Excluder cum Shrimp Sorting Device (JFE-SSD), whcih traps mature shrimp in the bottom portion of the net while allowing juvenile shrimp to swim out of the mesh net unharmed. The device also retains mature finfish in the upper portion of the net while allowing small fish of low commercial value to safely exit the shrimp trawl. The sorting of the shrimp and the finfish between the lower and upper parts of the net enhances profitability because it reduces sorting time on the deck which increases the useful fishing time of the trawler fishermen, and it prevents shrimp from becoming crushed under the weight of fish and bycatch hauled on deck which increases the shrimp's market value.

 

Turtle Excluder Device

Turtle Excluder Device is a specialized form of BRD designed for saving sea turtles caught incidentally during shrimp trawling. CIFT has developed an efficient indigenous TED design (CIFT-TED) for commercial shrimp trawling which offers 100% protection to sea turtles with minimal catch loss

 

Advanced technology in fisheries

• The Institute endeavors to promote the adoption of advanced technology among small-scale mechanised and traditional fishermen in order to enhance the productivity and profitability and sustainability of fishing operations.
• Acoustic fish detection devices such as fish finder.
• Electronic navigation and position fixing devices such as GPS.
• Satellite based remote sensing for potential fish aggregations.
• Energy conservation measures in fish harvesting.
• Fish aggregating devices

 

Fish Aggregating Devices (FADs)

The Institute has developed and standardized low-cost designs of floating FADs and benthic Artificial Reef (AF) modules in order to make the fishing operations energy efficient and cost-effective, for the benefit of traditional fishermen operating low impact fishing gears such as gill nets and lines.