When fishing, it’s common for fish to swallow the hook so deeply that it’s difficult to remove. In such cases, anglers generally accept the idea that simply cutting the leader and releasing the fish will save them. However, the National Fisheries Research Center of Japan recently published experimental results confirming that simply cutting the leader and releasing the fish is the right thing to do.
The experimental method announced by the Aquaculture Research Institute of the Fisheries Research Center of Japan involved cutting the necks of trout (Japanese salmon) caught by fishing and releasing them after they had swallowed a hook, attaching tags to them.
The results of the experiment showed that the needles remaining in the body of the maggot corrode, break off, and are excreted.
Additionally, it was found that 72 of the 77 released fish, or 93.5%, survived, and 53 of them, or 68.8%, were caught again by fishing.
When releasing a caught fish, it is best to release it in a healthy state if possible, but if the fish has swallowed a needle, it is better to cut the leash short and release it rather than forcibly removing the needle.
Until now, it was unclear how to properly dispose of the animal, but I hope that in the future, when it is difficult to remove the needle, many people will realize that they can survive by simply cutting the leash and releasing it.
I would also like to point out that catch-and-release, which is practiced with good intentions, can take the lives of fish, contrary to one’s intentions.
As I discussed in the article “Catch and Release Practice Begins with the Selection of Hooks” a long time ago, in countries like the United States where fishing is a sport, even the hooks used to increase the survival rate of fish are regulated in detail, even when the fish are released. It is true that research support from the government and companies plays a big role in making such regulations possible.
However, in contrast, in our country, there is a government move to impose a surcharge on anglers based on an absurd research report that the average catch of anglers is 6.5 kg. Therefore, we cannot help but criticize the convenient and desk-bound administration that sticks to a complacent policy of one-sided regulation.
As mentioned above, the United States has detailed regulations on even the hooks used for fishing, and numerous research reports provide the basis for this. I think that the research results announced by the University of California in 2018 are something that our anglers should think about and put into practice at least once, so I will summarize them.
It is something that can often be seen at fishing spots, but when fish are pulled out to release their catch, they often injure their mouths and sometimes even damage their organs.
If you are not used to removing the hook and you think it might cause damage to the fish’s mouth or body, rather than forcing it out, cut the line and release it to increase the chances of survival.
Researchers at the University of California caught 10 shiner perch with nets and 10 with hooks near Canada’s Bamfield Marine Sciences Centre, and then used high-speed cameras to observe how the feeding behavior of the hook-caught fish was affected by injuries around the mouth.
As a result, it was discovered that fish with injuries around their mouths due to fishing hooks ate less quickly, and the way fish with injuries around their mouths inhale food is said to be similar to how we drink beverages through a straw with a hole in it.
The researchers say more detailed research is needed to determine how the decline in the fish’s ability to forage affects their long-term survival. Information about the research team can be found on their website (Higham Lab) .