Substantial economic, social and nutritional benefits are derived from capture fisheries. There i... more Substantial economic, social and nutritional benefits are derived from capture fisheries. There is a great diversity in the fish harvesting systems in use in the capture fisheries sector of India. They range from simple fishing gears such as gill nets, hooks and lines or traps fabricated from basic materials at minimal cost to advanced mechanized systems operating trawls, purse seines or long lines requiring high investment and skill. During the last three decades, rapid advances have taken place in fish detection techniques, fishing gear materials and design, fabrication and operation of fishing gear. These developments have led to increased production from the sector. However, emerging issues of long-term sustainability of fishery resources, protection of biodiversity, environmental safety and energy conservation, have highlighted the need for adoption of responsible fishing techniques as enshrined in the FAO Code of Conduct for Responsible Fisheries. In recent years, increased focus is given for diversification of fishing techniques targeting underexploited resources like oceanic tuna and other pelagic, mesopelagic and deep sea demersal resources.
The present study was conducted in the Dal lake of Kashmir using two types of cast net viz., poly... more The present study was conducted in the Dal lake of Kashmir using two types of cast net viz., polyamide (PA) multifilament stringless with fixed pockets and polyamide (PA) multifilament stringed cast net to assess the catch composition and length weight distribution of fishes caught in the nets and to compare their catching efficiency in this lake. The study was based on 50 operations by each type of gear. A total of 9 species of fishes were caught in the study period. It was observed that Schizothorax labiatus (20.7%), Schizothorax niger (17.7%) and Cyprinus carpio communis (12.2%) dominated the catches. The average number and weight of fish caught was 2 and 126 g in PA multifilament stringless with fixed pockets cast net.
Knowledge on initial bioadhesion and composition of micro and macro nutrients within the biofilm ... more Knowledge on initial bioadhesion and composition of micro and macro nutrients within the biofilm matrix are recognised as essential for understanding the formation of biofilms. This communication highlights the heavy metal accumulation pattern in biofilms, influenced by the substrate and seasons. Natural biofilms were simultaneously grown on aluminium and steel panels for 72 hours by exposing them in the aquatic environment. Accumulation of toxic and nutrient metals in biofilms on different substrates and its seasonal variation were studied. Biofilms grown within 24 hours had shown significantly (p < 0.05) higher concentrations of trace metals in both the metal substrates. Trace metals accumulated over the substrates varied in different seasons. Among the metals, the accumulation of zinc was more during all the seasons. Biofilms grown on steel, concentrated more metals than on aluminium
The term ‘non target’ is usually used for fish caught unintentionally in a fishery while intendin... more The term ‘non target’ is usually used for fish caught unintentionally in a fishery while intending to catch other fish. Bycatch is of different species and undersized individuals of the target species or juveniles (Alsayes et al., 2009). These are either kept to be sold or discarded. Reduction of wastage in fisheries is a major goal of most fisheries organizations. However, there is a paucity of information available on bycatch associated with gillnet fisheries and what data is available is inconsistent in India (MRAG, 2012). More than fish and shell fish there are reports that gillnets accounted 76.5% accidental catch of turtles along the Indian coast during 1985-1995 (Rajagopal et al., 1996). Compared to trawl nets, in gillnets, the capture of non target species is lesser (Thomas et al., 2005). In India, the bycatch problem is more due to the multispecies nature of the tropical fisheries. So there is a need to assess bycatch impacts of fishery on stocks and ecosystems to identify ...
Mechanisation brings about major developments in fishing systems. Main fishing gear operated in O... more Mechanisation brings about major developments in fishing systems. Main fishing gear operated in Odisha state targeting large pelagics are drift gillnets. Odisha coast is an ecologically sensitive area having one of the four significant arribada beaches of Olive Ridley turtle, with three mass nesting beaches. Large mesh drift gillnets are reported to be the main gear contributing to incidental catch of turtles. The gillnet fishing sector has undergone many changes during the last few decades in terms of size of craft and gear, area of operation and trip duration. This paper deals with design and general features of mechanised gillnet fishing system operated in the coastal waters of Odisha. Presently mechanised gillnetters of 8-19 m LOA with 70 to 140 hp inboard engines go for voyage fishing of up to 30 days. Drift gillnets of the states are made of Polyamide (PA) and High Density Polyethylene (HDPE) having mesh size ranging from 80-380 mm. Total fleet size of the net increased substa...
The effect of preservative treatment on a secondary species of wood, Adina cordifolia (Haldu) was... more The effect of preservative treatment on a secondary species of wood, Adina cordifolia (Haldu) was studied. Panels were impregnated with creosote, an oil borne preservative, and copper-chrome- arsenic (CCA), a water borne preservative, through immersion treatment. The compressive stress parallel to grain of panels at various preservative retention levels was assessed to find out the change in mechanical strength. An average reduction of 14% compressive stress was noticed in CCA treated haldu panels and slight increase of 2 - 6% was observed in creosote treated panels.
Length frequency of sardine, Sardinella longiceps (Valenciennes), caught in gill nets with mesh s... more Length frequency of sardine, Sardinella longiceps (Valenciennes), caught in gill nets with mesh size of 32, 34, 36, 38 and 40 mm operated off Cochin (Kerala) was recorded. Using this, the selectivity parameters of the nets of these mesh sizes were assessed. The size range of S. longiceps caught was 12 to 20 cm. The estimated selection factors ranged from 4.56 to 4.67 and the selection lengths ranged from 14.7 to 18.7 cm. Gill nets with mesh size less than 34 mm did not facilitate the escapement of S. longiceps which had not attained the stage of first maturity.
The torpedo scad, Megalaspis cordyla (Linnaeus, 1758) is a moderately large marine fish belonging... more The torpedo scad, Megalaspis cordyla (Linnaeus, 1758) is a moderately large marine fish belonging to family Carangidae. The largest recorded individual is 80 cm long (TL). The torpedo scad is distributed throughout the tropical and subtropical waters of the Indian and west Pacific Oceans. Results of selectivity studies in respect of torpedo scad using covered codend method carried out with a 18 m semi-pelagic trawl, fitted with 65 mm diamond mesh codend and 30 mm mesh codend cover, off Cochin, India, are presented in this research note. According to the selectivity studies, the L25, L50 and L75 values for torpedo scad were 231, 294 and 357 mm respectively. Based on size at first maturity (Lm) of torpedo scad reported as 250 mm (TL; unsexed), the codend mesh size that can be recommended to harvest the mature torpedo scad is estimated as 55 mm, for conventional diamond mesh codends.
Corrosion of fishing hooks is a major problem faced by hook and line fishing industry. This commu... more Corrosion of fishing hooks is a major problem faced by hook and line fishing industry. This communication presents the results of a study taken up to asses the corrosion resistance of round bent, flatted hook no. 7 with two different surface coatings; viz., tinned and blued. The hooks were exposed to 300 h of salt spray as per ASTM B117. The tinned hooks exhibited excellent performance in salt spray exposure in comparison to the blued fishing hooks. The exposure of the hooks to salt spray resulted in an appreciable weight loss viz., the tinned hooks incurred a loss of 5.37% from the initial weight while the blued hooks lost 20.54% of weight. The corrosion rate of the tinned and blued hooks were found to be 26.934 mpy (mills per year) and 106.298 mpy respectively.
Substantial economic, social and nutritional benefits are derived from capture fisheries. There i... more Substantial economic, social and nutritional benefits are derived from capture fisheries. There is a great diversity in the fish harvesting systems in use in the capture fisheries sector of India. They range from simple fishing gears such as gill nets, hooks and lines or traps fabricated from basic materials at minimal cost to advanced mechanized systems operating trawls, purse seines or long lines requiring high investment and skill. During the last three decades, rapid advances have taken place in fish detection techniques, fishing gear materials and design, fabrication and operation of fishing gear. These developments have led to increased production from the sector. However, emerging issues of long-term sustainability of fishery resources, protection of biodiversity, environmental safety and energy conservation, have highlighted the need for adoption of responsible fishing techniques as enshrined in the FAO Code of Conduct for Responsible Fisheries. In recent years, increased focus is given for diversification of fishing techniques targeting underexploited resources like oceanic tuna and other pelagic, mesopelagic and deep sea demersal resources.
The present study was conducted in the Dal lake of Kashmir using two types of cast net viz., poly... more The present study was conducted in the Dal lake of Kashmir using two types of cast net viz., polyamide (PA) multifilament stringless with fixed pockets and polyamide (PA) multifilament stringed cast net to assess the catch composition and length weight distribution of fishes caught in the nets and to compare their catching efficiency in this lake. The study was based on 50 operations by each type of gear. A total of 9 species of fishes were caught in the study period. It was observed that Schizothorax labiatus (20.7%), Schizothorax niger (17.7%) and Cyprinus carpio communis (12.2%) dominated the catches. The average number and weight of fish caught was 2 and 126 g in PA multifilament stringless with fixed pockets cast net.
Knowledge on initial bioadhesion and composition of micro and macro nutrients within the biofilm ... more Knowledge on initial bioadhesion and composition of micro and macro nutrients within the biofilm matrix are recognised as essential for understanding the formation of biofilms. This communication highlights the heavy metal accumulation pattern in biofilms, influenced by the substrate and seasons. Natural biofilms were simultaneously grown on aluminium and steel panels for 72 hours by exposing them in the aquatic environment. Accumulation of toxic and nutrient metals in biofilms on different substrates and its seasonal variation were studied. Biofilms grown within 24 hours had shown significantly (p < 0.05) higher concentrations of trace metals in both the metal substrates. Trace metals accumulated over the substrates varied in different seasons. Among the metals, the accumulation of zinc was more during all the seasons. Biofilms grown on steel, concentrated more metals than on aluminium
The term ‘non target’ is usually used for fish caught unintentionally in a fishery while intendin... more The term ‘non target’ is usually used for fish caught unintentionally in a fishery while intending to catch other fish. Bycatch is of different species and undersized individuals of the target species or juveniles (Alsayes et al., 2009). These are either kept to be sold or discarded. Reduction of wastage in fisheries is a major goal of most fisheries organizations. However, there is a paucity of information available on bycatch associated with gillnet fisheries and what data is available is inconsistent in India (MRAG, 2012). More than fish and shell fish there are reports that gillnets accounted 76.5% accidental catch of turtles along the Indian coast during 1985-1995 (Rajagopal et al., 1996). Compared to trawl nets, in gillnets, the capture of non target species is lesser (Thomas et al., 2005). In India, the bycatch problem is more due to the multispecies nature of the tropical fisheries. So there is a need to assess bycatch impacts of fishery on stocks and ecosystems to identify ...
Mechanisation brings about major developments in fishing systems. Main fishing gear operated in O... more Mechanisation brings about major developments in fishing systems. Main fishing gear operated in Odisha state targeting large pelagics are drift gillnets. Odisha coast is an ecologically sensitive area having one of the four significant arribada beaches of Olive Ridley turtle, with three mass nesting beaches. Large mesh drift gillnets are reported to be the main gear contributing to incidental catch of turtles. The gillnet fishing sector has undergone many changes during the last few decades in terms of size of craft and gear, area of operation and trip duration. This paper deals with design and general features of mechanised gillnet fishing system operated in the coastal waters of Odisha. Presently mechanised gillnetters of 8-19 m LOA with 70 to 140 hp inboard engines go for voyage fishing of up to 30 days. Drift gillnets of the states are made of Polyamide (PA) and High Density Polyethylene (HDPE) having mesh size ranging from 80-380 mm. Total fleet size of the net increased substa...
The effect of preservative treatment on a secondary species of wood, Adina cordifolia (Haldu) was... more The effect of preservative treatment on a secondary species of wood, Adina cordifolia (Haldu) was studied. Panels were impregnated with creosote, an oil borne preservative, and copper-chrome- arsenic (CCA), a water borne preservative, through immersion treatment. The compressive stress parallel to grain of panels at various preservative retention levels was assessed to find out the change in mechanical strength. An average reduction of 14% compressive stress was noticed in CCA treated haldu panels and slight increase of 2 - 6% was observed in creosote treated panels.
Length frequency of sardine, Sardinella longiceps (Valenciennes), caught in gill nets with mesh s... more Length frequency of sardine, Sardinella longiceps (Valenciennes), caught in gill nets with mesh size of 32, 34, 36, 38 and 40 mm operated off Cochin (Kerala) was recorded. Using this, the selectivity parameters of the nets of these mesh sizes were assessed. The size range of S. longiceps caught was 12 to 20 cm. The estimated selection factors ranged from 4.56 to 4.67 and the selection lengths ranged from 14.7 to 18.7 cm. Gill nets with mesh size less than 34 mm did not facilitate the escapement of S. longiceps which had not attained the stage of first maturity.
The torpedo scad, Megalaspis cordyla (Linnaeus, 1758) is a moderately large marine fish belonging... more The torpedo scad, Megalaspis cordyla (Linnaeus, 1758) is a moderately large marine fish belonging to family Carangidae. The largest recorded individual is 80 cm long (TL). The torpedo scad is distributed throughout the tropical and subtropical waters of the Indian and west Pacific Oceans. Results of selectivity studies in respect of torpedo scad using covered codend method carried out with a 18 m semi-pelagic trawl, fitted with 65 mm diamond mesh codend and 30 mm mesh codend cover, off Cochin, India, are presented in this research note. According to the selectivity studies, the L25, L50 and L75 values for torpedo scad were 231, 294 and 357 mm respectively. Based on size at first maturity (Lm) of torpedo scad reported as 250 mm (TL; unsexed), the codend mesh size that can be recommended to harvest the mature torpedo scad is estimated as 55 mm, for conventional diamond mesh codends.
Corrosion of fishing hooks is a major problem faced by hook and line fishing industry. This commu... more Corrosion of fishing hooks is a major problem faced by hook and line fishing industry. This communication presents the results of a study taken up to asses the corrosion resistance of round bent, flatted hook no. 7 with two different surface coatings; viz., tinned and blued. The hooks were exposed to 300 h of salt spray as per ASTM B117. The tinned hooks exhibited excellent performance in salt spray exposure in comparison to the blued fishing hooks. The exposure of the hooks to salt spray resulted in an appreciable weight loss viz., the tinned hooks incurred a loss of 5.37% from the initial weight while the blued hooks lost 20.54% of weight. The corrosion rate of the tinned and blued hooks were found to be 26.934 mpy (mills per year) and 106.298 mpy respectively.
This document presents information on loss and waste in gillnet and trammel net fisheries in Indi... more This document presents information on loss and waste in gillnet and trammel net fisheries in India. It is based on the final report of a study implemented by the Central Institute of Fisheries Technology (CIFT) of the Indian Council of Agricultural Research in collaboration with Integrated Coastal Management (ICM), India, a development consultancy firm. The study was conducted from October 2016 to March 2018 and funded by FAO as part of the Food Loss Assessment and Waste Reduction Programme. It was a follow-up to a workshop on food loss organized by FAO and ICAR-CIFT in Cochin, India, in April 2015, which indicated that significant fish loss was occurring in gillnet and trammel net fisheries. This document was prepared by Venkatesh Salagrama of ICM. Dr E. Vivekanandan, Consultant, Bay of Bengal Programme InterGovernmental Organization, India provided technical guidance to the research team during the implementation of the study. Dr Yvette Diei-Ouadi, Products, Trade and Marketing Branch (FIAM), Fisheries and Aquaculture Department, FAO, managed the support for the study, and provided technical backstopping. Ansen Ward (FIAM), Susana Siar, and Pingguo He, Fishing Operations and Technology Branch, Fisheries and Aquaculture Department, FAO, assisted in the preparation of the study report. Grateful appreciation is given to Gloria Loriente, FAO, for the professional work in the layout design and publishing of this document. The material in the annexes is reproduced as submitted.
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