From the desk of Bob Boese

HOOKED FISH MORTALITY

Bob Boese - Aug 13, 2012

Thibeaux was on the first day of his new job as assistant caretaker of the church graveyard when he suddenly heard strange music. No one else was around, so he carefully looked for the source. Troubled by the unusual sounds, he walked up the rows of crypts until, finally, he found the music coming from a tomb with a headstone that read: Clarence Couchon, Beloved Musician and Friend.

"He was that famous Zydeco player," Thibeaux remembered. He put his hand on the headstone and could feel the music vibrating the granite. Despite his best efforts to follow the tune, the eerie music sounded like it was being played backwards.

For the next few days, Thibeaux visited the tomb every day and listened to Couchon's crypt. Every day there was strange music, each time a little different but always sounding like it was played backwards.

On Sunday a crowd gathered by the tomb and, as the music played, someone asked the priest if it was a miracle.

"No," the priest answered. "Clarence is just decomposing."

Many items are more controversial than fly fishing justifies. It's a hobby and it should be fun, not provoke arguments. That's a nice sentiment, but not always true. Consider the question of whether the equipment or the lure designates fly fishing. What side you take determines your position on Czech nymphing and Tenkara. Is attractant a boon or a sin? How evil is a three fly rig? Should there be private waters? If you chased down all the issues, it would eventually bring you to Catch and Release.

C&R is habitual with many fly fishermen who treat it almost like religion. It is also mandated in many locations. Even for meat fishermen, catching fish beyond the legal bag limit demands C&R. When anything is this widely practiced, there is going to be controversy. Whether or not to remove a hook from a deeply hooked fish is such a controversy.

A surprising amount of research has been done on the mortality of fish which inhaled a hook. Consider the following from the Florida Fish and Wildlife Conservation Commission: (http://myfwc.com/research/saltwater/fish/snook/reduce‑catch‑release‑mortality/)

Hook wounds may appear minor to anglers, but damage to the gills, eyes, or internal organs can be fatal. If the fish is hooked deep in the throat or gut, research shows that it is best to cut the leader at the hook and leave the hook in the fish. Prolonged attempts to remove the hook often do more harm than good. In the Fish and Wildlife Research Institute's study of release mortality in snook, 24 snook were deep hooked. We removed the hooks from 12 snook, and we left the hook intact and cut the leader in the other 12 snook. We found that four of the 12 deep-hooked snook died after the hooks were removed. None died when we simply cut the leader and left the hook alone. Fish are capable of rejecting, expelling, or encapsulating hooks. Encapsulation is a process whereby the fishes' healing process causes the hook to be covered with an inert matrix of calcified material; or a-cellular tissue. Steel and bronze hooks are less toxic and are rejected or "dissolved" sooner than are stainless steel and cadmium-plated or nickel-plated hooks.

If you are really curious and have a lot of time to read technical documents, good articles discussing fish mortality from removed versus retained hooks can be found at:

http://www.fws.gov/filedownloads/ftp_nctccsp/Coggins%20AFM/3b_hooking%20mortality%20review.pdf and http://www3.carleton.ca/fecpl/pdfs/FishRes%20‑%20Stein%20et%20al%202012.pdf. Both of these articles reference (and have links to) many more studies on this subject, not all of which have conclusions that agree. When it comes to being controversial, a well-known and often quoted outdoor writer, Ralph Manns, has published articles indicating hook removal is not more harmful to fish survival than line cutting. (See http://www.bassdozer.com/articles/manns/hook_in_out.shtml) The situation gets more confusing when respected organizations such as the LSU Ag Center cite a Texas Parks and Wildlife study on largemouth bass.

Of the 240 fish captured, 19 were observed to be bleeding and nine (47%) of these died. Bleeding was observed more often for fish hooked in the throat (48%) and gill (50%) than for fish hooked in the mouth (1%). Anglers cut off and left hooks in 16 of 21 throat-hooked largemouth bass. Eight (50%) of these fish and two of the five (40%) throat-hooked fish from which the hook had been removed were dead in 72 hours. For all fish, the larger the fish, the lower the mortality.... http://www.seagrantfish.lsu.edu/resources/factsheets/catch_release.htm

Compare that to the following from Fisheries Research (2009) as cited at http://www.mendeley.com/research/cut‑the‑line‑or‑remove‑the‑hook‑an‑evaluation‑of‑sublethal‑and‑lethal‑endpoints‑for‑deeply‑hooked‑bluegill/ 

During holding experiments we noted the highest mortality levels in fish for which the hook was removed (33% after 48h and 44% after 10 days). Mortality rates were lowest for the controls (0% after 48 hours and 4% after 10 days) and intermediate for the line-cut treatment (8% after 48 hours and 12.5% after 10 days). After 48 hours, 45.5% of the fish from the line-cut treatment group were able to expel the hook originally embedded in their esophagus, and at the end of the 10 day study, 71.4% had expelled the hook. Even with the hook left in the esophagus, fish were able to feed although at lower rates than controls during the first 48 hours of holding. By 10 days post-capture, there were no differences in feeding rates as evidenced by growth patterns among the treatment groups. Collectively, the findings from this study demonstrate that cutting the line is a more effective release method than removing the hook when fish are deeply hooked.

Here is yet another example from Fisheries Research, Volume 113, Issue 1, January 2012 on a bonefish study:

Overall, 46% of bonefish held in large holding tanks expelled hooks within a 14-day observation period. Hooks located in the lip were expelled 2.6 times more frequently than hooks located in the gut. Barbless hooks were expelled 3.9 times faster when located deep in the oral cavity compared to barbed hooks, but there was no difference in expulsion rates among barbed and barbless hooks in shallow-hooked fish. For the two hook sizes studied, hook size had no impact on hook expulsion rates or duration of hook retention regardless of hook location or type. The presence of a hook had no significant effect on weight change, indicating the presence of a hook did not impede feeding ability.

What does this mean for fly fishermen? Frankly, not much if you are using dry flies and poppers. Both of these flies are rarely taken deeply. Most research agrees that lip hooked fish have a very high survival rate, occasionally 90+%. No issues there. Similarly, few freshwater patterns use stainless or plated hooks that don't degrade, which leaves wet flies, nymphs and saltwater flies.

If you are fishing nymphs, the chances are you are using light tippet that shouldn't impede eating. Hence, cutting tippet and leaving a hook in the fish's gullet would appear to be a better alternative to trying to extract the hook. However, using barbless hooks makes removal easier and at least one study says carefully removing a barbless hook causes little or no damage. If you have a survival friendly hook removal tool (something better than needle nose pliers) scientists might be hard pressed to say removing a barbless hook is not an acceptable approach. Wet flies may be more susceptible to a deep hooking situation. The problem here is that the tippet may not be as light as a nymph and the size of the fly itself may create esophagus blockage. Attempting removal is not a terrible idea, if the hook is barbless. If not, leaving the hook is probably the better approach.

Hooked fish mortality - Bob Boese
Saltwater hooks are another issue entirely. The Florida FWCC statement above expresses one side of the argument. Researchers on the other side say saltwater hooks never degrade. Few saltwater fishermen use barbless hooks but, and here's the good part, the vast majority of deep hook sets occur with live or cut bait. Poppers should result in lip hooks. Baitfish, shrimp and crab imitation flies might result in deep hooking, but there is a different solution - circles hooks. See http://www.seagrantfish.lsu.edu/pdfs/factsheets/circlehook.pdf.

Thanks to physics, that are easier to accept than understand, circle hooks almost always result in hooking in the corner of the mouth. Of course there are issues, the first of which is that the only commercially tied circle hook flies I know of are on 8/0 hooks. Second, it takes a while to adjust to the fact that you don't set the hook on a circle hook. All you want to do is wait for the fish to move off and maintain pressure. Adjusting your reaction to not setting when you have a strike is hard. Eventually, the hook is supposed to move to the corner of the mouth and the fish hooks itself. The downside is that hooking efficiency of a circle hook may be diminished because a fly might not be taken deeply enough for the circle hook magic to transpire.

There are plenty of circle hook options that work fine for clousers, deceivers, and even small sizes for crabs and shrimp. A very good article on circle hook flies and available hooks written by Lefty Kreh can be found at: http://archives.flyfisherman.com/content/circle‑hooks/2. You might start with a Mustad C71S Circle Streamer hook which is essentially the same size and design as the 34007, except, of course for the circle. More tyers are experimenting with circle hooks and most report (on various forums) successful tying and catching. One last note on circle hooks, however, is that they can be very difficult to get out of the fish's jaw because you have to turn it 280 degrees to get it out. One solution to aiding this process is to de-barb the hook. There will be no additional lost fish and when you have turned the hook enough it will slide out.

If you are adamant about one side of this argument, don't forget that there will be others just as adamant on the other side and both of you can find research to justify your position.

Have fun.

Antoine and Gerald Robichaud were brothers who cheated, swindled, scammed and stole from everyone they ever met. The entire town and surrounding community despised them and everyone was aware of how disreputable and dishonest they were.

One day, Antoine Robichaud died.

Although they never attended church, Gerald went to Father LeBlanc and offered a huge donation if LeBlanc would hold a funeral mass and say the appropriate words. Gerald said there would be an even larger donation if Father Leblanc would refer to Antoine as "a saint" during the eulogy.

The priest was troubled by the request, however, it was a very poor church and it desperately needed repairs.


The Funeral began and the priest started with the usual prayers and followed the rites and traditions. In closing, after making a few generic comments about the man in the box, he paused and turned to face the remaining brother.

He began, "As you all know, the departed was an awful individual with the morals of a wolf and the integrity of a jackal. However, compared to Gerald, he was a saint."

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