In recent times with the advancement of science, a number of fishing techniques, which rely on physico-chemical stimulation such as light, electricity, sound etc. have been innovated. Some of the modern fishing techniques have been described below.
Echo-sounder
Echo-sounder is useful for the detection of fishing school particularly pelagic fishes. Generally two types of echo-sounder are used- low frequency echo sounder emits waves of 15-20 KHZ. It is used to detect the fish school. High frequency echo-sounder emits waves of 200 KHZ. It is used to examine the fish school more closely. The components of echo-sounder are transmitter, transducer, receiver and recorder.
Sonar technique
Sonar technique is based on the principle of the echo sounder but it performs horizontal sounding for detecting fish school. The technique is useful for purpose seining. It covers a much wide area of fish school.
Net Sonde Technique
It is a special acoustic instrument to measure the fishing depth and opening of the trawl. The catch of the trawl and the distribution of fish around the trawl can be observed at a time.
Fish finder technique
It gives a view of fish school under water. An infrared transmitter is lowered from the ship to a certain depth. The intensity of emission reaching the water surface is constantly watched by an infrared telescope from the ship. Any fish school passing across the emission line, reduce the intensity of emission near the water.
Pye fish finder
It is an electronic echo-sounder found in deep water trawling.
Electric fishing
Direct electric current pass through water. In this method fish became paralised and are ultimately caught in the net. It is extremely used in demarsal fishing like shrimp, lobster, tuna, big shark etc.
Fishing by pump
In this method, fish are captured by sucking them through a wide hose pipe. Fish are attached by light or electricity. This method is used commercially in the Caspean Sea for Chepeonella spp.
Fishing by light
In this In this method light is used to attract fish towards the net and then caught.
Satellite fishing
Satellite can also be employed for the collection of temporary fishing grounds.
Remote Sensing
Remote sensing involves obtaining and analysing pictures and other data for a distance, usually from aeroplanes or from satellites. By this technique, information about the characteristics of aquatic media like food chain, photosynthesis, productivity and even nutrient distribution can be obtained.
Night vision TV camera
This is a highly specialized techniques and an expensive one. Light air craft carrying a night vision TV camera flies near the water surface. In this method, night vision camera is used to monitor fish school at night from air craft.
Laser beam
In this method, highly controlled laser beams are directed towards the sea from low flying aircraft. Reflection from the water surface and the sea bed are detected by a sensor. Weaker reflections created from the fish schools are detected.
Echo-sounder
Echo-sounder is useful for the detection of fishing school particularly pelagic fishes. Generally two types of echo-sounder are used- low frequency echo sounder emits waves of 15-20 KHZ. It is used to detect the fish school. High frequency echo-sounder emits waves of 200 KHZ. It is used to examine the fish school more closely. The components of echo-sounder are transmitter, transducer, receiver and recorder.
Sonar technique
Sonar technique is based on the principle of the echo sounder but it performs horizontal sounding for detecting fish school. The technique is useful for purpose seining. It covers a much wide area of fish school.
Net Sonde Technique
It is a special acoustic instrument to measure the fishing depth and opening of the trawl. The catch of the trawl and the distribution of fish around the trawl can be observed at a time.
Fish finder technique
It gives a view of fish school under water. An infrared transmitter is lowered from the ship to a certain depth. The intensity of emission reaching the water surface is constantly watched by an infrared telescope from the ship. Any fish school passing across the emission line, reduce the intensity of emission near the water.
Pye fish finder
It is an electronic echo-sounder found in deep water trawling.
Electric fishing
Direct electric current pass through water. In this method fish became paralised and are ultimately caught in the net. It is extremely used in demarsal fishing like shrimp, lobster, tuna, big shark etc.
Fishing by pump
In this method, fish are captured by sucking them through a wide hose pipe. Fish are attached by light or electricity. This method is used commercially in the Caspean Sea for Chepeonella spp.
Fishing by light
In this In this method light is used to attract fish towards the net and then caught.
Satellite fishing
Satellite can also be employed for the collection of temporary fishing grounds.
Remote Sensing
Remote sensing involves obtaining and analysing pictures and other data for a distance, usually from aeroplanes or from satellites. By this technique, information about the characteristics of aquatic media like food chain, photosynthesis, productivity and even nutrient distribution can be obtained.
Night vision TV camera
This is a highly specialized techniques and an expensive one. Light air craft carrying a night vision TV camera flies near the water surface. In this method, night vision camera is used to monitor fish school at night from air craft.
Laser beam
In this method, highly controlled laser beams are directed towards the sea from low flying aircraft. Reflection from the water surface and the sea bed are detected by a sensor. Weaker reflections created from the fish schools are detected.
