Fishing crafts and gears in India fall into two main categories - non-mechanized and mechanized. Non-mechanized crafts include dugout canoes, plank-built canoes, and coracles. Mechanized crafts include motorized boats like line boats, trap boats, and trawlers. Nets and gears used include gill nets, purse seines, bag nets, and trawls which are used to catch different types of fish depending on the body of water and fish species. Fishing crafts and gears vary widely across India.
lobsters and crab fisheries in INDIA is a vast and enormous amount of catch and exports are being made.
this slide describes about the methods, distribution, annual landings and important species of lobster and crabs in India.
A fishing gear is the tool with which aquatic resources are captured, whereas the fishing method is how the gear is used. Gear also includes harvesting organisms.
Dr. K. Rama Rao
Department of Zoology
Govt, Degree College
TEKKALI; Srikakulam Dt: A.P.
Hill areas offer good scope for the development- of fisheries—both for commercial and sport purposes.
The coldwater fishery resources in India comprise high and mid-altitude lakes, rivers, streams, their tributaries and reservoirs dammed across such rivers.
The importance of coldwater fisheries lies in their unique biodiversity, valuable germplasm and maintenance of environmental quality in hills.
Coldwater fishes breed naturally but since some species have been listed as endangered, therefore artificial breeding is now being practiced to restore the diversity.
This document discusses mud crab and lobster culture in India. It provides information on the four main species of mud crabs found in the Indo-Pacific region - Scylla serrata, S. olivacea, S. tranquebarica, and S. paramamosain. Mud crab farming is done commercially using grow-out and fattening methods in ponds. Three commercially important lobster species for India are also described - Panulirus polyphagus, P. homarus, and P. ornatus. Their life cycles and biology are summarized. Lobster farming can be done by growing juveniles in ponds to market size or fattening medium sized lobsters. Optimal water
Aquaculture is the farming of aquatic organisms such as fish, mollusks, crustaceans, and aquatic plants. It involves some form of intervention in the rearing process, such as regular stocking, feeding, and protection from predators. Farming implies individual or corporate ownership of the stock being cultivated. India has a long history of aquaculture and is now the second largest producer of aquaculture products globally. Aquaculture makes an important contribution to India's food supply and economy through diverse practices in freshwater, brackishwater, and marine environments.
So this is a visual PPT, made with reference book - Applied Fishery Science By S.M Shafi and most of the data was collected from FAO and CMFRI . Molluscan fisheries here in this PPT is related with India so most of the organisms are indigenous. Have a look . It would be pictorial but once you know about the topic it's the best
The fish pituitary gland is located in the brain and has two parts - the glandular and nervous parts. It can be collected through dissection by removing part of the scalp or through the foramen magnum. The gland is then preserved in alcohol or acetone and stored. For injection, it is homogenized in water or saline, centrifuged, and the supernatant is used. Females receive two injections of the extract 6 hours apart at specific dosage levels based on the fish species.
lobsters and crab fisheries in INDIA is a vast and enormous amount of catch and exports are being made.
this slide describes about the methods, distribution, annual landings and important species of lobster and crabs in India.
A fishing gear is the tool with which aquatic resources are captured, whereas the fishing method is how the gear is used. Gear also includes harvesting organisms.
Dr. K. Rama Rao
Department of Zoology
Govt, Degree College
TEKKALI; Srikakulam Dt: A.P.
Hill areas offer good scope for the development- of fisheries—both for commercial and sport purposes.
The coldwater fishery resources in India comprise high and mid-altitude lakes, rivers, streams, their tributaries and reservoirs dammed across such rivers.
The importance of coldwater fisheries lies in their unique biodiversity, valuable germplasm and maintenance of environmental quality in hills.
Coldwater fishes breed naturally but since some species have been listed as endangered, therefore artificial breeding is now being practiced to restore the diversity.
This document discusses mud crab and lobster culture in India. It provides information on the four main species of mud crabs found in the Indo-Pacific region - Scylla serrata, S. olivacea, S. tranquebarica, and S. paramamosain. Mud crab farming is done commercially using grow-out and fattening methods in ponds. Three commercially important lobster species for India are also described - Panulirus polyphagus, P. homarus, and P. ornatus. Their life cycles and biology are summarized. Lobster farming can be done by growing juveniles in ponds to market size or fattening medium sized lobsters. Optimal water
Aquaculture is the farming of aquatic organisms such as fish, mollusks, crustaceans, and aquatic plants. It involves some form of intervention in the rearing process, such as regular stocking, feeding, and protection from predators. Farming implies individual or corporate ownership of the stock being cultivated. India has a long history of aquaculture and is now the second largest producer of aquaculture products globally. Aquaculture makes an important contribution to India's food supply and economy through diverse practices in freshwater, brackishwater, and marine environments.
So this is a visual PPT, made with reference book - Applied Fishery Science By S.M Shafi and most of the data was collected from FAO and CMFRI . Molluscan fisheries here in this PPT is related with India so most of the organisms are indigenous. Have a look . It would be pictorial but once you know about the topic it's the best
The fish pituitary gland is located in the brain and has two parts - the glandular and nervous parts. It can be collected through dissection by removing part of the scalp or through the foramen magnum. The gland is then preserved in alcohol or acetone and stored. For injection, it is homogenized in water or saline, centrifuged, and the supernatant is used. Females receive two injections of the extract 6 hours apart at specific dosage levels based on the fish species.
The document provides information about the mud crab (Scylla serrata), including its classification, distribution, ecology, and methods for farming and hatchery management. It notes that mud crabs are found naturally in the Indo-Pacific region and are an economically important species. Mud crab farming can be done using grow-out systems, where young crabs are raised for 5-6 months until market size, or fattening systems, where soft-shelled crabs are raised for a shorter period. Hatchery management involves broodstock selection and care, spawning and larval rearing techniques, and achieving survival rates as high as 18.1% compared to the world average of 3-3.5
Cage culture involves confining fish or shellfish within mesh enclosures in existing water bodies like ponds, rivers, and oceans. Some key advantages are the flexibility to use different water resources with minimal initial investment. However, there are also disadvantages like the need for complete diets, high risk of disease transmission due to crowding, potential for localized water quality issues, and limitations to production yields. Cage aquaculture has rapidly expanded in recent decades and continues to adapt to growing global demand through clustering cages and developing more intensive cage farming systems.
This document discusses the Indian oil sardine fishery. It provides details on the distribution, peculiar characteristics, feeding habits, habitat, reproduction, fecundity, spawning season, age and growth, size of capture, mode of harvest, utilization, maximum sustainable yield, IUCN status, current stock status, management measures, and production trends of the Indian oil sardine. Key points include that it is distributed along India's western coast from Gujarat to Kerala, feeds mostly on plankton, reaches sexual maturity at 1 year old and 150mm in length, and production peaked at over 720,000 tonnes in 2012. Mesh size regulation is used for management.
Various parameter have been used by different authors for classification of fishing gear and fish catching methods. According to Hardy (1947) - Hardy best his classification on fishing method like luring, snaring and attacking.According to Umali (1950)- Umali classified fishing gear of Philippines as non-textile device and textile device.According to Davis (1958) – Davis made an effort to classified gears of England without drawing definite line of demarcation.According to Dumont and Sundstrom (1961) – commercial fishing gears of united state where classified based on similarity of types.According to Andres Von Brandt (1972) – Von Brandt classified the fish catching methods of the world on the basis of how the fish are catch. The subgroups of Von Brandt 1972 classification are made on parameter like material construction and method of operation. International Standard Statistical Classification of Fishing Gear (ISSCFG-1980) has classified the fishing gear in accordance with the internationally recognized standard Von Brandt 1972 classification is the most popular one and is universally accept.Andres Von Brandt has classified is fish catching methods of the world in to 16 major groups based on how the fish are caught.
Ornamental fish culture provides opportunities for entrepreneurship and income generation. It requires a minimum of 500 sq ft of land and access to fresh water and electricity. Selection of quality broodstock is important, as different species prefer different water parameters for breeding. Beginners should start with livebearers like guppies and later move to egg-layers, focusing on one species at a time. CIFA has developed technologies for breeding 16 indigenous ornamental fish species and commercializing an endangered species. It conducts national training programs and facilitates entrepreneurs with business plans and information on government subsidies.
The document summarizes the anatomy and histology of the integumentary system of fish. It describes the main layers of fish skin as the cuticle, epidermis, basement membrane, dermis, and hypodermis. It provides details on the cell types found in the epidermis including Malpighian cells, mucous cells, club cells, and pigment cells. It also discusses scales, embedded in the dermis, which provide protection. The dermis contains collagen fibers and pigment cells like melanophores, xanthophores, and iridophores. Fins are described as large folds of skin with special bone support.
This document discusses estuaries and estuarine fisheries in India. It defines an estuary and notes that India has over 55 estuaries along its eastern and western coasts, totaling approximately 30,000 square kilometers. Several major river systems like the Ganges, Mahanadi, Godavari and Krishna form highly productive estuarine ecosystems. The document examines the fish production and ecology of estuaries like the Hooghly, Krishna, Godavari, Mahanadi, Chilka, Pulicat Lake, and Kerala backwaters. It provides details on fish catches, species diversity, and threats like overfishing in several of India's important estuarine systems.
Oysters can change their gender. ...
Humans eat about two billion pounds of oysters every year.
Oysters are very healthy food source, they are loaded with vitamin C, D, and the B vitamins. ...
Clams can live up to 35 years. ...
Clams are high in protein and iron. ...
Lobsters sometimes eat their young.
1. Mud crabs, commonly known as Scylla serrata and Scylla tranquebarica, are found along the coasts of India, particularly in Andhra Pradesh, Tamil Nadu, and Kerala. Mud crab farming is an important industry in several Southeast Asian countries.
2. The document provides details on mud crab habitat and feeding habits, reproduction, and different farming techniques such as pond culture, pen culture, and cage culture. It also discusses economic considerations of mud crab culture and fattening.
3. Mud crab farming can be a profitable activity, with net profits of over Rs. 1 lakh possible per crop using various culture methods over 4-7 months.
A fish hatchery breeds and rears fish and shellfish through early life stages. Hatcheries produce larvae and juveniles to support aquaculture. They benefit the industry by allowing for out of season production, genetic improvement through selective breeding, and reducing reliance on wild-caught juveniles. A hatchery consists of tanks for rearing larvae and holding broodstock. Key components include water storage tanks, larval rearing tanks, postlarval holding tanks, and equipment for water filtration, aeration, heating and monitoring water quality. Hatcheries are designed based on the target species' biology and local conditions like water availability.
The document provides information on the culture of mud crabs. It discusses the scientific classification of mud crabs, their biology, hatchery technology, and culture methods. Mud crabs can be cultured through monoculture or polyculture. They reach market size within 6 months when cultured and common diseases include white spot disease and bacterial shell diseases. The document concludes that mud crab farming is becoming popular due to demand and provides alternative livelihood opportunities through crab fattening.
Coracles are dominant fishing craft in South Indian reservoirs. They are made of a large, circular basket with low sides and a hide covering. Fishermen use gill nets, shore seines and longlines from coracles. Catamarans, made of 3-5 logs tied together, are used in pairs for boat seines and individually for longlines and cast nets. Common inland fishing gears include cast nets, gill nets, seines, lift nets, drag nets, hooks and lines, and traps. Trawlers have been tried experimentally in some Indian reservoirs.
This document provides an overview of different fishing gears and techniques. It discusses the main categories of active gears like trawls and dredges that chase fish, and passive gears like gillnets and traps that sit and allow fish to approach. Specific gear types are described in detail such as purse seines, trammel nets, longlines and various trawl nets. Both advantages and disadvantages of different fishing methods are presented. The document emphasizes the importance of selecting the right fishing gear and using it sustainably to minimize environmental impacts.
This document presents different culture methods for farming mussels. There are three main types of culture methods: bottom culture, intertidal and shallow water culture, and deep water culture. Intertidal and shallow water culture methods include rack culture, tray culture, wig-wam culture, and rope-web culture. Rack culture involves hanging mussel collectors on bamboo poles. Tray culture uses bamboo or metal trays suspended on poles. Deep water culture methods are raft culture, using rafts to hold suspended rope collectors, and long-line culture, which uses underwater lines anchored at the bottom.
• Fish needs some extra feed
along
with
available
natural feeds in water for
their regular growth.
• This extra feed which are
provided to fish is called
supplementary feed of fish.
Rice bran
•Refined pulse and wheat roughage
•Mustard or sesame cake
•Fish-meal (fish powder)
•Blood and innards of bird or animal
•Green leaves of various vegetables
•Minerals and vitamins
•Kitchen leftovers, etc.
This document discusses the traits and culture methods of important cultivable fish and shellfish in fresh water aquaculture. It covers carp species like Catla catla and Labeo rohita that are commonly farmed using methods like polyculture. Exotic carp species such as the silver carp are also discussed. Culture methods for catfish including Clarias batrachus are described. Finally, the giant freshwater prawn Macrobrachium rosenbergii is covered, noting its life cycle and that it can be cultured alone or with other species.
This document discusses various aspects of fisheries management including its aims, principles, factors to consider, tools, and advantages. Effective fisheries management requires understanding species, populations, environmental impacts, and implementing measures like regulated fishing, habitat improvements, and monitoring to balance exploitation with sustainable populations. Key goals are providing catch while maintaining populations above biological limits to prevent stock declines.
This document provides information on monoculture fish farming techniques used in India. It discusses how monoculture farming involves raising only one type of fish species in a pond. It notes that monoculture allows for easy monitoring of fish performance but can lead to issues like water quality degradation. The document also outlines the steps involved in monoculture fish farming, including construction of ponds, breeding fish, and transferring fry and fingerlings between ponds. It provides details on suitable fish species used in Indian monoculture like various carp species.
This document summarizes traditional fishing crafts and gear used in India. It describes the main types of crafts used on the east and west coasts of India, including catamarans, masula boats, dinghies, and built-up boats. It also outlines the major net types like seine nets, drift nets, trawl nets, and hook-and-line techniques like hand lines, pole-and-lines, and long lines. The document provides detailed descriptions of fishing methods and how specific gears are constructed and operated to catch different types of fish.
1) Fishing gears can be categorized as either active gears like dredges, trawls and seines that actively capture fish, or passive gears like traps and gill nets that wait for fish to become entangled.
2) Dredges are dragged along the seafloor to capture bottom-dwelling species but can harm benthic habitats. Traps like pots are stationary nets that allow entry but not exit.
3) Gill nets are vertical panels of netting that ensnare fish by their gills. Problems include bycatch of non-target species. Trawlers use large cone-shaped nets that are towed along the bottom to catch a variety of species.
The document provides information about the mud crab (Scylla serrata), including its classification, distribution, ecology, and methods for farming and hatchery management. It notes that mud crabs are found naturally in the Indo-Pacific region and are an economically important species. Mud crab farming can be done using grow-out systems, where young crabs are raised for 5-6 months until market size, or fattening systems, where soft-shelled crabs are raised for a shorter period. Hatchery management involves broodstock selection and care, spawning and larval rearing techniques, and achieving survival rates as high as 18.1% compared to the world average of 3-3.5
Cage culture involves confining fish or shellfish within mesh enclosures in existing water bodies like ponds, rivers, and oceans. Some key advantages are the flexibility to use different water resources with minimal initial investment. However, there are also disadvantages like the need for complete diets, high risk of disease transmission due to crowding, potential for localized water quality issues, and limitations to production yields. Cage aquaculture has rapidly expanded in recent decades and continues to adapt to growing global demand through clustering cages and developing more intensive cage farming systems.
This document discusses the Indian oil sardine fishery. It provides details on the distribution, peculiar characteristics, feeding habits, habitat, reproduction, fecundity, spawning season, age and growth, size of capture, mode of harvest, utilization, maximum sustainable yield, IUCN status, current stock status, management measures, and production trends of the Indian oil sardine. Key points include that it is distributed along India's western coast from Gujarat to Kerala, feeds mostly on plankton, reaches sexual maturity at 1 year old and 150mm in length, and production peaked at over 720,000 tonnes in 2012. Mesh size regulation is used for management.
Various parameter have been used by different authors for classification of fishing gear and fish catching methods. According to Hardy (1947) - Hardy best his classification on fishing method like luring, snaring and attacking.According to Umali (1950)- Umali classified fishing gear of Philippines as non-textile device and textile device.According to Davis (1958) – Davis made an effort to classified gears of England without drawing definite line of demarcation.According to Dumont and Sundstrom (1961) – commercial fishing gears of united state where classified based on similarity of types.According to Andres Von Brandt (1972) – Von Brandt classified the fish catching methods of the world on the basis of how the fish are catch. The subgroups of Von Brandt 1972 classification are made on parameter like material construction and method of operation. International Standard Statistical Classification of Fishing Gear (ISSCFG-1980) has classified the fishing gear in accordance with the internationally recognized standard Von Brandt 1972 classification is the most popular one and is universally accept.Andres Von Brandt has classified is fish catching methods of the world in to 16 major groups based on how the fish are caught.
Ornamental fish culture provides opportunities for entrepreneurship and income generation. It requires a minimum of 500 sq ft of land and access to fresh water and electricity. Selection of quality broodstock is important, as different species prefer different water parameters for breeding. Beginners should start with livebearers like guppies and later move to egg-layers, focusing on one species at a time. CIFA has developed technologies for breeding 16 indigenous ornamental fish species and commercializing an endangered species. It conducts national training programs and facilitates entrepreneurs with business plans and information on government subsidies.
The document summarizes the anatomy and histology of the integumentary system of fish. It describes the main layers of fish skin as the cuticle, epidermis, basement membrane, dermis, and hypodermis. It provides details on the cell types found in the epidermis including Malpighian cells, mucous cells, club cells, and pigment cells. It also discusses scales, embedded in the dermis, which provide protection. The dermis contains collagen fibers and pigment cells like melanophores, xanthophores, and iridophores. Fins are described as large folds of skin with special bone support.
This document discusses estuaries and estuarine fisheries in India. It defines an estuary and notes that India has over 55 estuaries along its eastern and western coasts, totaling approximately 30,000 square kilometers. Several major river systems like the Ganges, Mahanadi, Godavari and Krishna form highly productive estuarine ecosystems. The document examines the fish production and ecology of estuaries like the Hooghly, Krishna, Godavari, Mahanadi, Chilka, Pulicat Lake, and Kerala backwaters. It provides details on fish catches, species diversity, and threats like overfishing in several of India's important estuarine systems.
Oysters can change their gender. ...
Humans eat about two billion pounds of oysters every year.
Oysters are very healthy food source, they are loaded with vitamin C, D, and the B vitamins. ...
Clams can live up to 35 years. ...
Clams are high in protein and iron. ...
Lobsters sometimes eat their young.
1. Mud crabs, commonly known as Scylla serrata and Scylla tranquebarica, are found along the coasts of India, particularly in Andhra Pradesh, Tamil Nadu, and Kerala. Mud crab farming is an important industry in several Southeast Asian countries.
2. The document provides details on mud crab habitat and feeding habits, reproduction, and different farming techniques such as pond culture, pen culture, and cage culture. It also discusses economic considerations of mud crab culture and fattening.
3. Mud crab farming can be a profitable activity, with net profits of over Rs. 1 lakh possible per crop using various culture methods over 4-7 months.
A fish hatchery breeds and rears fish and shellfish through early life stages. Hatcheries produce larvae and juveniles to support aquaculture. They benefit the industry by allowing for out of season production, genetic improvement through selective breeding, and reducing reliance on wild-caught juveniles. A hatchery consists of tanks for rearing larvae and holding broodstock. Key components include water storage tanks, larval rearing tanks, postlarval holding tanks, and equipment for water filtration, aeration, heating and monitoring water quality. Hatcheries are designed based on the target species' biology and local conditions like water availability.
The document provides information on the culture of mud crabs. It discusses the scientific classification of mud crabs, their biology, hatchery technology, and culture methods. Mud crabs can be cultured through monoculture or polyculture. They reach market size within 6 months when cultured and common diseases include white spot disease and bacterial shell diseases. The document concludes that mud crab farming is becoming popular due to demand and provides alternative livelihood opportunities through crab fattening.
Coracles are dominant fishing craft in South Indian reservoirs. They are made of a large, circular basket with low sides and a hide covering. Fishermen use gill nets, shore seines and longlines from coracles. Catamarans, made of 3-5 logs tied together, are used in pairs for boat seines and individually for longlines and cast nets. Common inland fishing gears include cast nets, gill nets, seines, lift nets, drag nets, hooks and lines, and traps. Trawlers have been tried experimentally in some Indian reservoirs.
This document provides an overview of different fishing gears and techniques. It discusses the main categories of active gears like trawls and dredges that chase fish, and passive gears like gillnets and traps that sit and allow fish to approach. Specific gear types are described in detail such as purse seines, trammel nets, longlines and various trawl nets. Both advantages and disadvantages of different fishing methods are presented. The document emphasizes the importance of selecting the right fishing gear and using it sustainably to minimize environmental impacts.
This document presents different culture methods for farming mussels. There are three main types of culture methods: bottom culture, intertidal and shallow water culture, and deep water culture. Intertidal and shallow water culture methods include rack culture, tray culture, wig-wam culture, and rope-web culture. Rack culture involves hanging mussel collectors on bamboo poles. Tray culture uses bamboo or metal trays suspended on poles. Deep water culture methods are raft culture, using rafts to hold suspended rope collectors, and long-line culture, which uses underwater lines anchored at the bottom.
• Fish needs some extra feed
along
with
available
natural feeds in water for
their regular growth.
• This extra feed which are
provided to fish is called
supplementary feed of fish.
Rice bran
•Refined pulse and wheat roughage
•Mustard or sesame cake
•Fish-meal (fish powder)
•Blood and innards of bird or animal
•Green leaves of various vegetables
•Minerals and vitamins
•Kitchen leftovers, etc.
This document discusses the traits and culture methods of important cultivable fish and shellfish in fresh water aquaculture. It covers carp species like Catla catla and Labeo rohita that are commonly farmed using methods like polyculture. Exotic carp species such as the silver carp are also discussed. Culture methods for catfish including Clarias batrachus are described. Finally, the giant freshwater prawn Macrobrachium rosenbergii is covered, noting its life cycle and that it can be cultured alone or with other species.
This document discusses various aspects of fisheries management including its aims, principles, factors to consider, tools, and advantages. Effective fisheries management requires understanding species, populations, environmental impacts, and implementing measures like regulated fishing, habitat improvements, and monitoring to balance exploitation with sustainable populations. Key goals are providing catch while maintaining populations above biological limits to prevent stock declines.
This document provides information on monoculture fish farming techniques used in India. It discusses how monoculture farming involves raising only one type of fish species in a pond. It notes that monoculture allows for easy monitoring of fish performance but can lead to issues like water quality degradation. The document also outlines the steps involved in monoculture fish farming, including construction of ponds, breeding fish, and transferring fry and fingerlings between ponds. It provides details on suitable fish species used in Indian monoculture like various carp species.
This document summarizes traditional fishing crafts and gear used in India. It describes the main types of crafts used on the east and west coasts of India, including catamarans, masula boats, dinghies, and built-up boats. It also outlines the major net types like seine nets, drift nets, trawl nets, and hook-and-line techniques like hand lines, pole-and-lines, and long lines. The document provides detailed descriptions of fishing methods and how specific gears are constructed and operated to catch different types of fish.
1) Fishing gears can be categorized as either active gears like dredges, trawls and seines that actively capture fish, or passive gears like traps and gill nets that wait for fish to become entangled.
2) Dredges are dragged along the seafloor to capture bottom-dwelling species but can harm benthic habitats. Traps like pots are stationary nets that allow entry but not exit.
3) Gill nets are vertical panels of netting that ensnare fish by their gills. Problems include bycatch of non-target species. Trawlers use large cone-shaped nets that are towed along the bottom to catch a variety of species.
Traditional fishing Craft of India by Ashish sahuAshish sahu
Fishing crafts are most essential for catching the fish in large scale in water bodies. A large variety of crafts (boats) have been designed for marine and inland fishing in India. The types of fishing crafts of India falls under two general categories. These are Non –mechanized and mechanized fishing crafts.
Based on the topographical variations and difference in habits and habitats of fishing, different types of crafts and gears are used in various inland water system of India. The simplest and most primitive types of craft used for fishing in inland water are the rafts and songas, operated in calm water. In the larger rivers and estuaries subject to strong current and tidal movement, sturdier plank boats are used.
Definition
Fishing vessel is a floating device used for fishing activities like, fishing, fish transportation, Research and training purpose.
This document discusses different types of fishing methods. It begins by defining fishing and fishing equipment. There are two main types of fishing: without gear (hand fishing) and with gear (gear fishing). Fishing methods that use gear include nets, traps, line fishing, fish attraction devices, and electrical fishing. The most common fishing method is net fishing, which accounts for 67% of fishing in India and 54% worldwide. Other major fishing methods include fish screening, fish trapping, and line fishing. The document provides details on specific net fishing techniques like gill nets, purse seines, and trawls. It also describes traps, line fishing, and the use of fish attraction devices.
Tugboats come in different types for various uses. They are smaller than ships but powerful and versatile. Harbor tugs operate in ports and inland waters, towing and assisting vessels. Escort tugs guide large ships through narrow or dangerous passages. Seagoing tugs can tow very large vessels and are used for salvage or relocating structures. Tugboats are equipped to fight fires and break ice. Online listings make it easy to find and hire tugboats worldwide for different needs.
Fishing gear refers to equipment used to catch fish and includes both active gears like trawls that guide fish into the path and passive gears like nets that fish must swim into. Common fishing methods include using various nets like gill nets, traps, hooks and lines, and trawl nets. Trawl nets are large cone-shaped nets towed along the seabed that can catch bottom, demersal, and pelagic species but also disturb the seabed and result in bycatch. Other fishing methods include using fish screens, fish attraction devices, and electrical fishing.
Dr. K. Rama Rao
Department of Zoology
Govt, Degree College
TEKKALI; Srikakulam Dt: A.P.
Phone: 9010705687
Fishing gears are defined as tools used to capture marine/aquatic resources, whereas how the gear is used is the fishing method.
The document summarizes a study tour conducted by M.Sc. students from Babasaheb Bhimrao Ambedkar University in Lucknow, India to survey fish netting. The study tour was led by Dr. Abha Mishra and involved students Shailendra Kumar, Rajesh Kumar Gautam, Vipin Kumar, and Preeti Sagar. The document describes various types of nets used for fishing, including dip nets, cast nets, drift nets, gill nets, boat seines, trawl nets, and shore seines. It also discusses fishing crafts, gear, and methods like hand picking, spears, harpoons, and fish poisoning.
This document provides an overview of various fishing gears and methods. It begins with an outline of the course topics, which include the study and classification of fishing gears and crafts. It then describes different gear types such as beam trawling, demersal otter trawling, dredging, drift nets, fish attraction devices, gill/fixed nets, handlines, jigging, longlining, pelagic trawling, pole and line fishing, and pots. For each gear type, it explains how it is used to target particular species. The document provides a comprehensive reference for different fishing techniques around the world.
The document discusses different types of ships, their characteristics, and functions. It describes 10 common types of ships: container ships, tanker ships, cargo ships, bulk carriers, roll-on roll-off ships, passenger ships, fishing vessels, offshore vessels, submarines, and aircraft carriers. For each type of ship, it provides details on their design purpose, cargo carried, and typical uses.
The document discusses the use of artificial light in fishing operations to attract and aggregate fish. It describes how light fishing works, the historical development of light sources used, and how certain light characteristics like intensity, color and wavelength influence fish behavior. It provides examples of light fishing practices in several countries like Japan, Indonesia, Ghana, East Africa and India. It also discusses the ecological impacts of light fishing like overfishing, catching immature fish, increased bycatch, and regulations implemented in different countries to manage light fisheries.
The Vembanad Lake estuarine system in Kerala, India is an important fishery resource but its health is declining. It supports over 100 fish and shellfish species and once produced over 8,500 tons of catch annually, but production has fallen significantly. Key threats include obstruction of water flows, sand mining, habitat destruction, pollution, and unsustainable fishing practices. Conservation efforts are needed to restore the lake's fisheries and protect the livelihoods of local fishing communities.
Liferafts and lifeboats are two types of survival craft carried on ships. Liferafts are collapsible and stored in canisters while lifeboats are open and require periodic inspections. There are three main types of liferafts - coastal, offshore, and ocean - which provide varying levels of protection and are suitable for different voyage lengths. Ship management companies must ensure all required safety equipment is provided on lifeboats and liferafts according to international regulations.
BRDs have been developed through intensive research, taking into consideration the characteristics of the fishery and geographical peculiarities.
There has been a significant reduction in the world bycatch levels during the past two decades due to the increased use of BRDs in trawling.
Cooperation among the fishing industry, scientists and other stakeholders is fundamental for the success of bycatch management efforts.
BRDs, most appropriate to the regional fishing conditions should be adopted and enforced legally to ensure long term sustainability and biodiversity of the fishery resources.
Auxiliary marine machinery systems are essential for proper ship functioning. They include pumps, compressors, and blowers for fuel, water, and air systems. They also include separators, steering machinery, winches, cranes and other deck equipment. The machinery space houses these systems and its size depends on the equipment installed. Common auxiliary equipment includes engines, steering gear, deck machinery, blocks, pulleys, pumps, masts, derricks, rollers, gantries, and various types of winches used for specific fishing methods and vessel operations. Proper maintenance of critical components like engines is important for auxiliary system reliability.
Fishing provides important economic and nutritional benefits. There are many fishing methods that depend on the type of fish and environment. Methods include fishing by hand in streams, as well as using various gear like hooks, nets, traps, and electric currents from boats. Key gear includes long lines, gill nets, purse seines, and trawls, with mesh and net size tailored to the target species. Fishing supports many communities and employs a large portion of the population.
This document provides an overview of docks and harbours for construction. It defines key terms like dock and harbour. Harbours are sheltered areas used for loading/unloading vessels and providing refuge from storms. Harbours are classified as artificial, natural, or semi-natural. Planning requires studying site conditions. Requirements include sufficient depth, anchorage, and entrance width. Harbour features include breakwaters, docks, channels, jetties, and basins. Docks enclose areas for berthing ships, and can be wet or dry. Entrance channels should be deep and wide. Jetties project into water for berthing. Basins are used for parking and turning ships.
This document provides an overview of fishing vessels throughout history. It describes how early fishing vessels were constructed of materials like hide-covered frames and how Egyptians later developed sailboats. Over time, boats grew larger and were used for travel. The document also discusses the development of steam power in fishing vessels in the 1870s and the evolution of trawler designs. Modern trawlers are decked vessels equipped with technologies like navigation systems. The document outlines different types of trawling vessels and gear and describes operations and stability concerns for fishing vessels. It concludes with details about the world's largest fishing vessel.
Aquaculture is defined as the cultivation of aquatic organisms such as fish, shellfish, algae and other aquatic plants in natural or controlled marine or freshwater environments. It involves some form of intervention in the rearing process to enhance production, such as regular stocking, feeding and protection from predators. Aquaculture is commonly practiced in both freshwater and marine environments and can take place in ponds, tanks, cages or other contained structures. The history of aquaculture dates back thousands of years to ancient China where carp cultivation began, and it has since developed worldwide into a major food production industry.
This document discusses several parasites that commonly infect fish, including:
- Trypanosoma, a genus of parasites transmitted by blood-feeding invertebrates that occupies the bloodstream of vertebrate hosts.
- Ichthyophthiriasis multifilis, commonly known as "ich" or "white spot" disease, which infects the gills and skin and can be fatal.
- Dactylogyrus, a monogenetic trematode that attaches to the host's skin, fins, and gills with hooks and causes minimal damage.
- Several other parasites that commonly infect fish such as copepods, anchor parasites, and isopod crustaceans. Many cause
This document discusses fish protein concentrate (FPC) and its production. It describes FPC as a nutritious and inexpensive food that can help address protein malnutrition worldwide. Various methods are used to produce FPC, including physical, solvent extraction, and hydrolysis methods. Solvent extraction involves mincing fish and extracting lipids using solvents like hexane and ethanol at high temperatures. The final product is dried and milled into a powder that is stable, odorless, and high in protein content. FPC can be used to combat protein deficiency diseases and is incorporated into various food preparations.
Ecology is defined as the study of the relationships between living organisms and their environment. The term was coined by Ernst Haeckel in 1866 to refer to the inter-relationships between organisms and their environment. Ecology literally means the study of a organism's home or habitat. Modern ecology is often called environmental biology as it examines how organisms interact with each other and their non-living surroundings. A key focus of ecology is understanding ecosystems - the complex set of interactions within a community of organisms and between the community and its physical environment.
Freshwater, Brackish water and Marine fish culture of India by Dr. S. G. ChebbiSameer Chebbi
This document summarizes the history and current state of freshwater fish culture in India. It discusses how fish culture has ancient roots in India dating back thousands of years, but was traditionally small-scale. Technological advances like induced breeding in the 1950s revolutionized the industry. Carp culture is now a major economic activity, with scientific methods producing high yields. Different culture systems are used across regions depending on local conditions and resources. Freshwater fish culture continues to be an important and growing industry in India.
Plankton are small organisms that drift or float in marine and freshwater ecosystems. They include algae, bacteria, protozoa, and tiny animals. Plankton are the base of aquatic food webs, providing a food source for larger animals and ultimately humans. Their abundance varies depending on factors like light availability and nutrient levels. Plankton inhabit all bodies of water and play an important role in biogeochemical cycles.
- Grey mullet has been farmed for centuries in many countries using extensive and semi-intensive pond systems.
- It is an important aquaculture species in several countries and regions including Egypt, Russia, Korea, Taiwan, and India.
- Grey mullet is tolerant of a wide range of environmental conditions, grows quickly, and feeds on detritus, making it well-suited for aquaculture. However, juveniles can only tolerate wide salinity ranges once they reach 4-7 cm in length.
This document discusses fish diseases and control measures. It describes how fish can be affected by various pathogens like viruses, bacteria, fungi and parasites. Some common viral diseases discussed are Spring Viremia of Carp caused by Rhabdovirus, Swim Bladder Inflammation caused by SBI virus, and Viral Renal Disease of Eels. It also discusses Channel Catfish Viral Disease caused by Herpes virus and Pox Disease of Carps caused by Carp Pox virus. The document emphasizes the importance of basic knowledge of fish diseases for fish farmers and highlights how diseases can be controlled through proper pond maintenance and use of antibiotics.
The document describes the life cycle and development of the typical penaeid prawn Penaeus monodon. It discusses that wild gravid females spawn in open sea, and the planktonic larval stages last about 2 weeks until postlarvae are found in coastal and estuarine areas. The postlarvae then develop into juveniles and adults in estuaries before returning to sea to spawn. It outlines the 5 stages of ovarian development and spawning, where a female can produce 500,000-1,000,000 eggs per spawn. The document then details the characteristics and duration of the nauplius, protozoea, mysis, and postlarval stages in the praw
This document discusses shrimp hatchery production in India. It provides details on the site selection criteria for hatcheries, including the need for clean seawater supply and accessibility. It describes the typical layout of hatchery systems and production process from broodstock development and maturation to larval and postlarval rearing. By the early 2000s, India had over 1500 hatcheries producing shrimp and fish seeds to meet the growing demand from aquaculture.
Trypanosoma is a genus of parasitic flagellates that infects fish. It is transmitted between hosts by vectors like leeches. Common symptoms in infected fish include anemia from blood sucking and secondary infections. Dactylogyrus is a monogenetic trematode that attaches to fish skin, fins and gills through hooks, sometimes causing emaciation in severe infections. Ichthyophthiriasis multifilis, commonly known as ich, appears as white spots on fish skin and gills. It has a direct lifecycle involving a motile trophont stage in the fish and a free-swimming tomites stage that can infect other fish.
Fisherman cooperatives aim to improve the economic and social conditions of small-scale fishermen by carrying out business activities together that individual fishermen cannot achieve alone. They participate in activities like owning fishing vessels, providing credit, marketing and storing fish, transporting products, processing fish, and supplying fishing materials. Cooperatives help eliminate trader monopolies and provide fishermen with working capital and gear. The government supports cooperatives to improve fishermen's welfare, but initiatives must come from fishermen. Cooperatives need management, capital, and scale to compete effectively.
This document provides information on 14 different freshwater fish species commonly kept in aquariums, including their appearance, natural habitat, care requirements, breeding habits, and suitable foods. It describes the Cardinal Tetra as having a bright blue stripe contrasted by a red stripe, the Neon Tetra as having a red stripe halfway down its body, and the Piranha as having a long silver body and bright red tail with large sharp teeth. It recommends keeping most of these schooling and community fish in groups of 6 or more in a planted tank with hiding spaces.
The document lists the various species of fish, shellfish, crustaceans, and other marine animals found in Indian waters. It includes the scientific names and common names of species from several families, including carps, catfish, snakeheads, prawns, crabs, lobsters, mollusks, sharks, rays and others. The document appears to be providing an overview of the different types of freshwater and marine organisms available in India for industrial fish and fisheries.
Principles of fish preservation and processingSameer Chebbi
This document provides information on various methods for preserving fish, including salting, drying, smoking, chilling, freezing, canning, and pickling. It describes the basic processes for each method, such as using saltwater brine for wet salting, hanging fish to dry in sunlight, building smoking sheds and controlling fires for long smoking. The goal of preservation is to prevent spoilage and extend the shelf life of fish using techniques from chemistry, engineering and other sciences to maintain quality. Safety considerations for methods like pickled fish are also outlined.
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This document provides information on various freshwater aquarium fish species. It discusses their natural habitats, tank requirements, feeding, breeding behaviors, and other care details. Key fish mentioned include Cardinal Tetras, Black Widow Tetras, Neon Tetras, Hockey Stick Tetras, Piranhas, Rosy Barbs, Tiger Barbs, Zebra Danios, Goldfish, Koi Carp, Ghost Glass Cats, and Oscar Cichlids. The document is authored by Sameer G. Chebbi Ph.D from the Department of Zoology at Karnatak Science College, Dharwad.
This document discusses different types of fish migration. It describes potamodromous migration within freshwater systems, oceanodromous migration within marine systems, and diadromous migration between freshwater and marine systems. Diadromous migration includes catadromous migration patterns like eels that live in freshwater but spawn in the ocean, and anadromous patterns like salmon that live in the ocean but spawn in freshwater rivers and streams. The document provides details on the life cycles and migration routes of eels and salmon.
QUINALPHOS INDUCED BIOCHEMICAL AND PATHOPHYSIOLOGICAL CHANGES IN FRESHWATER E...Sameer Chebbi
This document discusses a study on the biochemical and pathophysiological changes in the freshwater fish Cyprinus carpio exposed to the organophosphate pesticide quinalphos. The study aims to understand the toxic effects of lethal and sublethal concentrations of quinalphos on C. carpio over different exposure periods. Biochemical parameters like proteins, oxidative stress markers, acetylcholinesterase activity, ions, and ATPases will be analyzed in the gills, kidney, and liver tissues of exposed fish. Histopathological changes and accumulation of the pesticide will also be examined in these tissues. The results will provide insights into the toxic impacts of quinalphos exposure on C. carpio at biochemical
India has rich marine fishery resources due to its long coastline and exclusive economic zone covering over 2 million square kilometers. The marine fish production has increased significantly over time to over 3 million metric tons annually, contributing approximately 40% of India's total fish production. Important fishery resources include varieties of fishes, crustaceans, mollusks, and seaweeds. The west coast accounts for 55% of total landings while the east coast accounts for 45%. Key species landed include oil sardine, Indian mackerel, penaeid prawns, croakers, and cephalopods.
Seaweeds products, processing and utilizationSameer Chebbi
This document discusses seaweeds and their utilization. It notes that seaweeds are a source of phyco-colloids like agar, algin, and carrageenan, which are used in food, chemical, and pharmaceutical industries. The document outlines the extraction processes for these three major phyco-colloids and their various industrial and commercial uses. It also provides details on seaweed production and the species commonly used for each type of phyco-colloid.
Phenomics assisted breeding in crop improvementIshaGoswami9
As the population is increasing and will reach about 9 billion upto 2050. Also due to climate change, it is difficult to meet the food requirement of such a large population. Facing the challenges presented by resource shortages, climate
change, and increasing global population, crop yield and quality need to be improved in a sustainable way over the coming decades. Genetic improvement by breeding is the best way to increase crop productivity. With the rapid progression of functional
genomics, an increasing number of crop genomes have been sequenced and dozens of genes influencing key agronomic traits have been identified. However, current genome sequence information has not been adequately exploited for understanding
the complex characteristics of multiple gene, owing to a lack of crop phenotypic data. Efficient, automatic, and accurate technologies and platforms that can capture phenotypic data that can
be linked to genomics information for crop improvement at all growth stages have become as important as genotyping. Thus,
high-throughput phenotyping has become the major bottleneck restricting crop breeding. Plant phenomics has been defined as the high-throughput, accurate acquisition and analysis of multi-dimensional phenotypes
during crop growing stages at the organism level, including the cell, tissue, organ, individual plant, plot, and field levels. With the rapid development of novel sensors, imaging technology,
and analysis methods, numerous infrastructure platforms have been developed for phenotyping.
The binding of cosmological structures by massless topological defectsSérgio Sacani
Assuming spherical symmetry and weak field, it is shown that if one solves the Poisson equation or the Einstein field
equations sourced by a topological defect, i.e. a singularity of a very specific form, the result is a localized gravitational
field capable of driving flat rotation (i.e. Keplerian circular orbits at a constant speed for all radii) of test masses on a thin
spherical shell without any underlying mass. Moreover, a large-scale structure which exploits this solution by assembling
concentrically a number of such topological defects can establish a flat stellar or galactic rotation curve, and can also deflect
light in the same manner as an equipotential (isothermal) sphere. Thus, the need for dark matter or modified gravity theory is
mitigated, at least in part.
The debris of the ‘last major merger’ is dynamically youngSérgio Sacani
The Milky Way’s (MW) inner stellar halo contains an [Fe/H]-rich component with highly eccentric orbits, often referred to as the
‘last major merger.’ Hypotheses for the origin of this component include Gaia-Sausage/Enceladus (GSE), where the progenitor
collided with the MW proto-disc 8–11 Gyr ago, and the Virgo Radial Merger (VRM), where the progenitor collided with the
MW disc within the last 3 Gyr. These two scenarios make different predictions about observable structure in local phase space,
because the morphology of debris depends on how long it has had to phase mix. The recently identified phase-space folds in Gaia
DR3 have positive caustic velocities, making them fundamentally different than the phase-mixed chevrons found in simulations
at late times. Roughly 20 per cent of the stars in the prograde local stellar halo are associated with the observed caustics. Based
on a simple phase-mixing model, the observed number of caustics are consistent with a merger that occurred 1–2 Gyr ago.
We also compare the observed phase-space distribution to FIRE-2 Latte simulations of GSE-like mergers, using a quantitative
measurement of phase mixing (2D causticality). The observed local phase-space distribution best matches the simulated data
1–2 Gyr after collision, and certainly not later than 3 Gyr. This is further evidence that the progenitor of the ‘last major merger’
did not collide with the MW proto-disc at early times, as is thought for the GSE, but instead collided with the MW disc within
the last few Gyr, consistent with the body of work surrounding the VRM.
Or: Beyond linear.
Abstract: Equivariant neural networks are neural networks that incorporate symmetries. The nonlinear activation functions in these networks result in interesting nonlinear equivariant maps between simple representations, and motivate the key player of this talk: piecewise linear representation theory.
Disclaimer: No one is perfect, so please mind that there might be mistakes and typos.
dtubbenhauer@gmail.com
Corrected slides: dtubbenhauer.com/talks.html
Authoring a personal GPT for your research and practice: How we created the Q...Leonel Morgado
Thematic analysis in qualitative research is a time-consuming and systematic task, typically done using teams. Team members must ground their activities on common understandings of the major concepts underlying the thematic analysis, and define criteria for its development. However, conceptual misunderstandings, equivocations, and lack of adherence to criteria are challenges to the quality and speed of this process. Given the distributed and uncertain nature of this process, we wondered if the tasks in thematic analysis could be supported by readily available artificial intelligence chatbots. Our early efforts point to potential benefits: not just saving time in the coding process but better adherence to criteria and grounding, by increasing triangulation between humans and artificial intelligence. This tutorial will provide a description and demonstration of the process we followed, as two academic researchers, to develop a custom ChatGPT to assist with qualitative coding in the thematic data analysis process of immersive learning accounts in a survey of the academic literature: QUAL-E Immersive Learning Thematic Analysis Helper. In the hands-on time, participants will try out QUAL-E and develop their ideas for their own qualitative coding ChatGPT. Participants that have the paid ChatGPT Plus subscription can create a draft of their assistants. The organizers will provide course materials and slide deck that participants will be able to utilize to continue development of their custom GPT. The paid subscription to ChatGPT Plus is not required to participate in this workshop, just for trying out personal GPTs during it.
ESR spectroscopy in liquid food and beverages.pptxPRIYANKA PATEL
With increasing population, people need to rely on packaged food stuffs. Packaging of food materials requires the preservation of food. There are various methods for the treatment of food to preserve them and irradiation treatment of food is one of them. It is the most common and the most harmless method for the food preservation as it does not alter the necessary micronutrients of food materials. Although irradiated food doesn’t cause any harm to the human health but still the quality assessment of food is required to provide consumers with necessary information about the food. ESR spectroscopy is the most sophisticated way to investigate the quality of the food and the free radicals induced during the processing of the food. ESR spin trapping technique is useful for the detection of highly unstable radicals in the food. The antioxidant capability of liquid food and beverages in mainly performed by spin trapping technique.
Current Ms word generated power point presentation covers major details about the micronuclei test. It's significance and assays to conduct it. It is used to detect the micronuclei formation inside the cells of nearly every multicellular organism. It's formation takes place during chromosomal sepration at metaphase.
1. FISHING CRAFTS OF INDIA
Dr Sameer G Chebbi
Industrial fish and fisheries Division
Dept. of Zoology,
Karnatak Science College, Dharwad
2. The use of crafts and gears in fishing technology plays very important role and help enhancing the production commercial
bases. The success of fishing largely depends on to how and which types of nets are used to capture the fish.
There are two main types of devices used to capture fishes in both marine and inland fisheries:
(1) Nets or gear — these are instruments used for catching fish.
(2) Crafts or Boats — It provides platform for fishing operations, carrying the crew and fishing gears.
Fishing crafts are essential for catching fish in large scale in the water bodies.
A variety of crafts have been designed for this purpose in India.
There are various types of gears and crafts used in different parts depending upon the nature of water bodies, the age of
fish and their species. Some nets are used without craft, however, others are used with the help of crafts. Generally,
locally made gears and crafts may be non-mechanized or mechanized.
The fishing crafts of India fall under two general categories in India
Non-mechanised boats
Mechanised boats
3. Non-mechanised Crafts
Dugout Canoe
Used for fishing within small distances from the shore
It is a small sized canoe made by scooping logs of wood in the form of a boat.
The “Odams”, “Thonies”, “Vanchies” etc. of the southeast and southwest coasts of India fall under
this category.
In calm weather, oars may be enough for propulsion; but if winds and currents prevail, sails may be
used.
For travel in the rougher waters of the ocean, dugouts can be fitted with outriggers.
One or two smaller logs are mounted parallel to the main hull by long poles.
Outriggers help to balance the boat by providing support from one side or both the sides.
5. DUGOUT CANOE
OUTRIGGER canoe
These are large size canoes of about 15 m long. It has narrow keel and single outrigger and
extended out with planks. They are commonly called as Rampani, because they are used for the
casting of the Rampani net for catching mackerels. They are operated on the Kanara and Konkan
coasts. Small size outriggers are used between Bhatkal and Majali.
Plank-built canoe
It is a kind of dug-out canoes. It is extended with planks on sides. They are popularly used on
coast of Kerala, Karnataka and North Bombay
These are boats made by stitching together planks of wood.
There are also an enlarged variety of dugout canoe made of planks on the side, largely used in
Kerala
In most of the plank built boats at present, the carvel type of boat is used.
6.
7. Masula
Non-rigid boat constructed with planks sewn together with coir rope, but without any
frames so as to withstand the severe knocking of the surfs.
They are made upto 9m in length, although generally smaller.
They are of various patterns viz. Bar boats in Orissa and Padava on the Andhra Coast
A variant with ribs inside has been developed in the area between Kakinada and
Maslipatnam.
8.
9. Carvel Boats
Carvel built or carvel planking is a method of boat building where hull planks are
fastened edge to edge, gaining support from the frame and forming a smooth surface.
10. Dinghi and Nauka •
These are carvel boats of Orissa and West Bengal Naukas, which are well designed and
constructed up to a size of 13mx3mx2m are quite spacious and are used for a variety of
purposes including fishing operations.
11. Tuticorin boats • These are also called the fishing luggers. They are carvel boats (11m x
2m x 1m), which are seaworthy in inshore waters. They are used more as mother ships
and cargo boats than directly for fishing.
12. Coracle
Coracles are light in weight, bowl shaped boats with a frame of woven grass, reeds, or
saplings covered with hides. Over the years, these circular crafts were constructed by
interwoven strips of bamboo and covered with water proof materials such as plastic bags
coated with a layer of coal tar. The boat size ranges between 1.50 - 2.00 meters dia. The
coracle weight ranges between 10 - 15kg. A single oar is used to propel the coracle. Two
fishers conduct the fishing in a coracle. Gillnet and long line are the common fishing
methods. Apart from being simple and inexpensive, these are durable (2 – 3 years) and
have good movability in all water bodies. It is profoundly used in Tamil Nadu, Andhra
Pradesh, and Karnataka.
13. FRP Boats • The term FRP is generally accepted to mean fibre reinforced plastic. • It is
composed of a series of reinforcements and liquid chemicals which when brought
together in specific proportions can be formed into strong, solid but flexible shapes. •
This FRP is then poured into a mould and when the FRP hardens it is cast out as a solid
and strong hull.
Different type of FRP boats can thus be built according to suitability by moulding them
as the need be. • The most common type of the mould used is called as the female
mould which is the mirror image of a finished hull. • The mould is made from a plug
which is the exact hand crafted replica of the final hull.
14. Advantages of FRP Advantages o
Reduction of maintenance • No leaks. Hulls are one continuous piece of FRP with no
joints or gaps to allow water into the hull. • No plank shrinkage when laid up. Wooden
hulls suffer from plank shrinkage when brought out of the water and laid up in the sun.
FRP does not shrink or swell so leakage and re-caulking are avoided.
15. Rot proof and resistant to borers. FRP is non- organic and will not rot. As a plastic it
cannot be eaten by marine borers. • Corrosion and electrolysis reduced. FRP is inert. As a
plastic it will not corrode. o Simpler construction. Once a mould is made, identical copies
of a hull can be made many times over and in a shorter time. o Reduction of skill levels
required once a basic training is received.
16. Motorized Craft • With the advent of mechanization of the fishing crafts, small and
medium sized boats are constructed with engines operated by oil to venture into distant
fishing grounds. • These motorized crafts are: line boats, trap boats, dol netter, gillnetter
and trawlers.
17. Hand line boat • Operated in both shallow and deeper waters. • Traditional hand liners
use no winch. • The gear usually consists of a few meters of monofilament of 0.5-1mm
diameter to the end of which is attached a hood and a sinker, usually a small stone. •
They are used to catch all kinds of demersal fish from motorized as well as small
mechanised vessels.
18. Trolling vessel • They tow lines extending on either side to catch pelagic species having
high individual value and good quality such as Tuna. • The lures are attached to outrigger
poles through lines that are towed by a slowly moving vessel. • The fished hooked after
snapping at the lure are brought on board as the line is hooked in. • The vessel length
vary and have a normal forward wheelhouse arrangement allowing a clear working deck.
19. Trawlers • A fishing trawler is a commercial fishing vessel designed to operate fishing
trawls. • Trawling is a method of fishing that involves actively dragging or pulling a trawl
through the water behind one or more trawlers. • Trawls are fishing nets that are pulled
along the bottom of the sea or in midwater at a specified depth. • A trawler may also
operate two or more trawl nets simultaneously (double-rig and multi-rig).
20. Modern trawlers are usually decked vessels designed for robustness. • Their
superstructure (wheelhouse and accommodation) can be forward, midship or aft. •
Motorised winches,electronic navigation and sonar systems are usually installed. • Fishing
equipment varies in sophistication depending on the size of the vessel and the
technology used.
21. Stern Trawler • On stern trawlers the trawl is set and hauled over the stern. • Stern
trawlers are designed with or without a ramp, depending on the size of the vessel. • Stern
trawlers are built for nearly all weather conditions. • Trawlers can work as single vessel in
bottom or midwater trawling or as pair trawlers where two vessels tow one large trawl or
a double trawl.
22. The most common deck layout of a stern trawler is such that the wheelhouse is just
forward of the midship with working deck behind. • The winch powered by the engine is
located behind the wheel house with the warps leading to the gantry located at the
middle or sides of the stern.
23. Outboard and inboard engines • An inboard motor is a marine propulsion system for
boats. • As opposed to an outboard motor where an engine is mounted outside the hull
of the craft, an inboard motor is an engine enclosed within the hull of the boat, usually
connected to a propulsion screw by a driveshaft.
24. An outboard motor is a propulsion system for boats, consisting of a self-contained unit
that includes engine, gearbox and propeller or jet drive, designed to be affixed to the
outside of the stern. • They are the most common motorized method of propelling small
watercraft. • As well as providing propulsion, outboards provide steering control, as they
are designed to pivot over their mountings and thus control the direction of thrust. • The
skeg also acts as a rudder when the engine is not running. Unlike inboard motors,
outboard motors can be easily removed for storage or repairs.
25. Mechanised craft and their various operations
Gill net • Gill nets are vertical panels of netting normally set in a straight line. • Fish may
be caught by gill nets in 3 ways : (1) wedged – held by the mesh around the body (2)
gilled – held by mesh slipping behind the opercula, or (3) tangled – held by teeth, spines,
maxillaries, or other protrusions without the body penetrating the mesh. • Most often fish
are gilled. • Gill nets catch fish that attempt to swim through the net, which are caught if
their head passes through the mesh but not the rest of the body.
26. The fish then becomes entangled by the gills as it attempts to back out of the net. • The
mesh size used depends upon the species and the size range being targeted. • Gill nets
may be set at or below the surface of water, on the sea bed or at any depth in between.
27. Bottom trawls • A bottom trawl is constructed like a cone-shaped net that is towed (by
one or two boats) on the bottom. • It consists of a body ending in a cod end, which
retains the catch. Normally the net has two lateral wings extending forward from the
opening. • The mouth of the trawl is framed by headline and ground rope. It is designed
to catch species living on or near the bottom. • Bottom contact with the gear is needed
for successful operations.
28. Three categories of bottom trawls can be distinguished based on how their horizontal
opening is maintained: beam trawls, bottom otter trawls, and bottom pair trawls. • Beam
trawls are commonly designed without wings • The ground rope equipped with rubber
discs, spacers etc. protect the trawl from damage. On very rough bottom special rock
hopper gears are used. • Trawl winches installed on deck control the trawling warps and
store them when not in use.
29. They are towed across the bottom at speeds ranging from 1 to 7 knots (0.5-3.5 m/s),
frequently between 3 and 5 knots. • Duration of a tow mainly depends on the expected
density of fish, the shape of the bottom and the slope in the fishing area, from a few mins
upto 10-12 hours, commonly 3-5 hours.
30. Seine Netting • It is a bottom fishing method and is of particular importance in the
harvesting of demersal or ground fish. • The fish are surrounded by a rope laid out on
the seabed with a trawl shaped net at mid-length. • As the rope is hauled in, the fish are
herded into the path of the net and caught • This method of fishing is less fuel-intensive
than trawling and produces a high quality catch.
31. Purse seining • This is the general name given to the method of encircling a school of
fish with a large wall of net. • The net is then drawn together underneath the fish so that
they are completely surrounded. • It is one of the most aggressive methods of fishing
and aims to capture large, dense shoals of mobile fish such as tuna, mackerel and
herring.
32. Long lining • Long lining is one of the most fuel efficient catching methods. • This
method is used to capture both demersal and pelagic fishes including swordfish and
tuna. • It involves setting out a length of line as long as 50-100km long, to which short
lengths of line carrying baited hooks are attached at intervals. • The lines may be set
vertically in the water column or horizontally along the bottom.
The size of the fish and species caught is determined by hook size and the type of bait
used.
33. Squid Jigging • Jigging is widely used to capture squid. • A jig is a type of grapnel,
attached to a line, which may be manually or mechanically jerked in the water to trap the
fish in its body. • Jig fishing usually happens at night with the aid of light attraction •
Squid jigging most often takes place at night with bright overhead lights to attract the
squid.
34. Jigs of various types, makes and colour are attached to the handline at 70 to 90 cm
intervals. Often as many as 8 to 12 jigs are on one line. • The lines are lowered to 30 to
100 m depth depending on the strength of the lights used, but less deep on a small boat
with one or two lamps. • It is important to keep the jig moving constantly in the water.
This is usually done by jerking the line, quickly pulling in the slack, jerking once again
and so on, until the jig is back to the surface
35. The line is then thrown out and allowed to sink to the desired depth, and the same
jerking motion is repeated over again. • Squids change colour as they move from shade
to light and vice versa and are therfore difficult to see. • This explains why they can be
difficult to catch and why jigging is most often the best method.
36. Bag net • Bag nets are containers made of nets that are dragged through the water,
collecting the fish in its path. • The nets are usually held open by a frame and the water
current.
38. Purse seines • It surrounds the fishes in vertical as well as horizontal position and is used
for pelagic fishery. • The netting walls are long. • It weighs about 1.25-1.5 tonnes, is 450m
long, 40-45m deep. • One end is joined to the main boat and other end encircles the area
and two ends are brought together, the fishes are encircled and the net is pulled up. •
Bout 20-25 people operate it.
39. Cast Net • Cast nets are popular variety of the small net operated by a single man. • It
usually has a string. • The net is cast by the sweep of the arm • When it spreads the fishes
are caught in it. • The commonly used one is called ‘Ghagria jal’, a circular or umbrellar
net with the chord at the apex. • The iron weights are attached on the margin.
• When the net is thrown, it spreads, sinks and the weights make it close. • It is used for
small fishes.
40. Rampani net • This type of seine net is operated from the beach or shore and hence the
name. • The net is made up of one hundred to several hundred rectangular pieces joined
together. • The net is formed of hemp. • Size of the mesh is smaller at the central portion
than at the side portion. • Wooden floats are attached to the head rope and stone sinkers
are attached to the foot rope.
The net is operated by 60-80 men. • In the beginning a scouting boat known as ‘thoni’ is
taken into the sea for a survey, and then as the shoal is sighted, a signal is given to the
other members on the shore. • Immediately one end of the leading rope is handed over
to the men on the shore and the net is carried by a larger boat called as ‘Pandi’. • The net
is then laid out in a semicircular fashion and then pulled by both the groups of men.
41. Tuna Longline • Longlining is a passive type of fishing technique making use of lines with
baited hooks as fishing gear. • The longline used for tuna fishing is made up of units each
of which consists of a main horizontal line about 250 to 800 m long with 4 to 15 branch-
lines, each with a wire leader and a hook. • The depth where the hooks are set in the
water column is a crucial element, this depth in which the longline is settled can be
regulated mainly by modifying the intervals of the main line between float lines and
partially by adjusting the length of float-line and/or the speed of shooting, to a lesser
extent, by modifying the length of the branch-lines.
42. Dol net • It is a bag net. Bag nets are conical bag like nets without wings. The size of the
mesh increases from bag portion to the mouth of the net. • Dol net is used on the coast
of Maharashtra. • It is a combination of bag net and a fixed trap and is used for Bombay
duck fishery. • It is a large bag net fixed in the sea by stout wooden poles or by thick
ropes anchored with heavy stones. • The net is maintained in a horizontal position facing
the tidal flow.
It is hauled up during the change of tide and the catch is emptied. • It is again fixed
against the changed direction of the tide. • It is operated from 15-20m to greater depths.
• The length of the net is about 56m. • The width near the mouth of the net is about 30m
and the height is about 18m. • The net gradually tapers towards the other end i.e. the
cod end.
43. The total length of the wooden pole is about 32m and about 8m remains below the
substratum. • The mesh size of the net near the mouth is 200m and it gradually reduces
to 10mm at the cod end.
44. Hooks and lines • Hooks and lines are gear where the fish is attracted by a natural or
artificial bait (lures) placed on a hook fixed to the end of a line or snood, on which they
get caught. • Hooks or metallic points (jigs) are also used to catch fish by ripping them
when they pass in its range of movement. • Hook and line units may be used singly or in
large numbers.
45. These gears are hauled by hand in small-scale fisheries whilst in large-scale fisheries
vessels are usually provided with powered line haulers, automatic jiggers, line reels, line
coilers and automatic hook handling and baiting systems. • These gears are suitable for
almost any size or type of vessel that can operate in the area being worked. • They can be
employed also without boat, directly from the coastline (jetties, rocks, beaches, etc.).
46. The fish are attracted by the natural or artificial bait, hooked, and held by the mouth until
they are brought aboard the operating vessel which periodically hauls the gear. • The
target species are pelagic, demersal and benthic. • Hooks and lines are generally
operated in a very wide range of depths, either in inland and sea waters. With line fishing
it is possible to catch fish on rough ground, even in their hiding places between the
rocks.
47. Pelagic trawls • The target is a wide variety of schooling pelagic species including
anchovies, herrings and mackerels, and fish that gather to spawn such as sea bass and
cod. • The front net sections are often made of very large meshes or ropes, which herd
the fish towards the back of the funnel-shaped net. Pelagic trawls may be towed by one
or two (pair trawl) boats.
• Advantages This method can be highly specific, with little bycatch of other species,
when targeting adult schools of one species. • Problems Pelagic trawls, especially large
pair trawls, are associated with bycatch of cetaceans, turtles, and other marine mammals
in some areas, such as common dolphins in the sea bass pair trawl fishery in the English
Channel. Bycatch of juvenile fish of the target species may also be high in some fisheries.