What is the existing situation of wild fish are overfished as bait of industrial farmed fish?

Up to this point regarding of industrial news, we have learned the possibility of mackerel born tuna and the advanced technologies and development of fully-closed life-cycle farming of brand fish. It is believed that armed with successful aquaculture of brand fish, we will be able to maintain the balance of endangered species and protect natural resource. However, a definitive conclusion cannot be drawn that easily.

According to Nikkei electronic version, from the book, Farmageddon: The True Cost of Cheap Meat (2014) by Philip Lymbery, CEO of Compassion in World Farming and Isabel Oakeshot, current situation of aquaculture has trigger an alarm.

In response to the decline of natural fish resources, most people would agree that fish farming is a preferred solution. However, Mr. Lymbery denies the theory for the following reasons: “Fish farming is designed to reduce the tension of the marine ecosystem by protecting the wild small fish from becoming prey of carnivorous fish such as salmon and trout, yet result shows more fish are actually taken from the sea”, the ration of “invested fish” versus “farmed fish” also evidently points out the fact that aquaculture is the use of extremely inefficient fish resources.

Reference Nikki Electronic Version:

From Mr. Lymbery‘s research “It takes up to 5 kilograms of wild fish to produce one kilogram of farmed salmon. By increasing amount of farmed fish, we will only accelerate the decreation of wild fish”

Larvae as alternative bait for wild fish

The curtained replacement of wild fish used as bait becomes the immediate challenge. Already industrial aquaculture in Japan is able to produce a safer alternative bait on land. It is the larvae of insects. In 2013, one of NHK programs called “OHAYO JAPAN” has reported the new update of bait used for fish farming.

“By using artificial fish powder or using insects as bait can be options to prevent depletion of natural resources.” By feeding Sparidae with this particular bait, with just 3 months, Sparidae can increase weight up to 20% more than regular fed ones. Moreover, it has been confirmed that insects contain a type of sugar, which enhances immunity of fish. Experiments also showed that fish infected with bacteria have significantly better survival rate.


Recently, due to increased price of wild small fish, chemical has been used to feed those farmed fish, and it has become a new problem. Certainly, by using cheaper and easily reproducible insects as bait, and at the same time can increase the quality of fish, no one would disagree with this idea.
For the future of technology development direction, especial for tuna that only take alive fish as bait, larvae might be able to use as substitution.

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Written by FUJI-KIZAI

Since its establishment in 1960, FUJI-KIZAI has been manufacturing and selling a wide variety of fishing equipment and supplies for longline fishing including aluminum sleeves, swivels, crimping tools, nylon lines. Also, gear and tackle for all kinds of fishing is available.