Analysis on the application of LED lights in fishing

What is the relationship between lighting and fishing? It turns out that many marine organisms have an instinctive phototaxis. For example, when a crab sees a light source, it slowly climbs over. Similarly, some fish will also concentrate on the source. In addition to some fish have a phototaxis instinct, there is another reason. According to the analysis, a large number of plankton and small fish are concentrated near the light source, and the fish swim there for food. Using this characteristic of fish, light fishing has gradually become an important fishing tool for fisheries.

In fact, using light to lure fishing groups can be said to be an old and advanced technology. It is said that it is old. As early as in the book "Ancient and Modern Secrets", it has recorded the story of fishermen fishing in China. The fishermen put hundreds of fireflies into the alpaca and sank them into the water to attract the fish and shrimps with the lightening habits and gather them.

It is said to be advanced. At present, the method of fishing with light is more diverse, and its harvest is multiplied. For example, the widespread application of "luminescent bacteria" and self-control lamps has brought more benefits to fishery production.

The reporter once followed the fishing boat to witness the scene of the light fishing: the roar of the fishing boat has already drowned the sound of the waves, leaving only the sea surface dotted with "stars". I saw a dense light bulb installed on the top of the reel cab. Dozens of bulbs with a power of 1000W need to be lit for more than an hour to attract the fish to the fishing boat. Then turn off the lights and cast nets for fishing. This is the light seine fishing.

"The effect of light fishing is very good, that is, this power consumption is too large, and the fuel cost is quite unbearable." Fisherman Lao Huang told reporters that the electricity used on board basically relies on diesel power generation. In recent years, with the declining fishery resources, coupled with the large number of fishing boats and increased competition, the fishermen have increased the power of the bulbs installed on the ships in order to catch more fish, which has grown from several kilowatts a few years ago. Hundreds of kilowatts now. The higher the power, the greater the power consumption. According to a statistical report, the diesel generator of the fishing boat generally consumes 231 to 272 g of fuel per kilowatt of electricity. At present, the energy consumption of fish-collecting lamps has accounted for more than 50% of the total energy consumption of fishing boats, and there is a trend of further increase.

LED instead of light source

At present, China's light-induced fisheries are developing rapidly. The light source of these fishing vessels uses traditional gold halide fishlights (hereinafter referred to as “metal halide lamps”), which have large fuel consumption and low utilization rate of light energy. In recent years, the increasingly tight energy has led to the rise in fuel prices, making more and more traditional light-induced fishing boats unable to make ends meet.

Moreover, once the metal halide lamp is extinguished, it needs to be cooled for several minutes or even tens of minutes before it can be lit again, which greatly affects the efficiency of the photo-sensing operation. Some fish, such as saury, need to adjust the light and start and extinguish them many times in order to achieve the effect of trapping the fish and improving the net production. After the metal halide lamp is extinguished, it is necessary to wait for the lamp body to be fully cooled before it can be turned on again, which seriously hinders the trapping of the saury.

On the other hand, since the metal halide lamp is a full-spectrum light source, in addition to visible light, there are a large amount of ultraviolet rays and infrared rays. Ultraviolet and infrared rays have no effect on trapping fish, but they can cause harm to the human body. Working under the light for a long time can burn skin and eyes, and easily induce skin cancer and cataract. As the power of the metal halide lamp increases, the extent of this damage increases dramatically.

It can be seen that the search for new alternative light sources for fishing lamps has become a necessity for the development of fisheries. In this case, the energy-saving properties of LEDs make it stand out in the fish-light market. As the fourth-generation lighting source lamp, LED lamp has the characteristics of energy saving, environmental protection, high efficiency, controllable light color, etc., which can greatly reduce fuel consumption and improve economic efficiency while ensuring output. It also plays a certain role in reducing the light damage to the crew.

According to reports, high-power LED lamps have been used as fishing light sources on fishing boats, and have been studied in Japan and other countries. In recent years, domestic research and experiments have begun, and breakthroughs have been made. From the current trial situation, fuel consumption is only one-third of the traditional fishing boat, but the catch rate is better than the traditional fishing boat.

Dimming, high power into key points

At present, in the research and development of LED fishing lights, Japan and other countries have already taken the lead. To open this market, the key is to make its own characteristics. Starting with spectral adjustment, combined with the habits of various fishes, we look for the “favorite” spectrum of fish.

Production practice shows that the primary factor affecting the effect of light trapping fish is the light source, which includes the intensity of the light source, the color of the light, and the configuration of the light fixture. For example, under dark adaptation conditions, adult fish have the highest phototaxis rate for blue and green light and the lowest phototaxis for red light. Under the conditions of dark adaptation and bright adaptation, the carp has the maximum phototaxis rate for purple and red light...

And "dimming" is precisely the strength of LED. LEDs are rich and colorful, with a variety of color options and light distribution. “But the optimal color of the LED fishing light spectrum has not yet been determined, which requires an interdisciplinary combination, not only to study the characteristics of the lamp, but also to study the different responses of various fish to light color and light intensity. LED sets of fish lights are mostly white, some are green, but in the end what is the best color fishing effect has not yet reached a definitive conclusion.

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