8 replies to this topic

[Betta132]

I kinda got to wondering... exactly how sensitive is a fish's mouth? I'm guessing catfish have pretty sensitive mouths, especially given their barbels and feeding habits, but what about other fish? Sunfish and such have mouths made of bone framework with a tough skin-like material between the sections. They can mouth gravel to find out if there are edible things in the gravel, but they don't seem to care if the gravel is poky. Also, when I've seen sunfish who have been hooked but not yet caught, they just start mouthing and kind of look confused as to why they can't swallow the food. They don't appear to be in pain, or if they are, they aren't bothered.

[Sean Phillips]

Interesting point, I'm with you on this as the structure of their mouth might be what determines this. While sunfish like bluegills and pumpkinseeds have bony mouths, other sunfish like crappies seem to have pretty sensitive mouths because they're so thin, hence their nickname the "papermouth".

[BSPhotography]

There was an experiment done years ago where a university injected fish (trout, albeit one of the least hardy fish out there) with saline, and then with an acid (I believe lemon juice or vinegar) to see their reactions, and timed how long the fish seemed to react to each.  They definitely reacted longer to the acid, but certain animal rights groups have taken the study to mean that fish feel pain, and fishing is evil. The reactions that they counted were mouth opening (in a sense of trying to spit something out), rubbing on the bottom substrate, and shaking (with or without the open mouth).  

[Betta132]

Trout have fleshier mouths, though, they would logically have more nerves. And there's a difference between a creature being aware of something that's wrong and trying to remove it and a creature actually experiencing pain. Or, since it's the mouth area, they could have been responding to stimulation to their taste sensors.

Fish definitely feel discomfort, at the very least. I've seen fish swimming oddly and sort of cringing when they're sick or otherwise unwell, so they're clearly able to feel that something is wrong, and that's unsurprising- they're vertebrates, after all. And I'm sure just about everyone who's ever kept a fish has seen one with ich in visible discomfort, flashing against rocks and such. I'm not contesting that fish feel pain, which is why I do not at all approve of using them as live bait, I'm just wondering how many nerves the average fish actually has in its mouth. Like I said, I've seen fish that are hooked and don't really appear to be all that aware of it, but I'm not sure if that's just tough-as-nails sunfish. 

And wouldn't a fish with a delicate and easily damaged mouth probably have fewer nerves, since it would be more likely to take damage? 

[Matt DeLaVega]

Non issue in my book. Barbless hook. I do more damage to my hands weekly than I inflict on fish mouths yearly, and I don't cry.

[centrarchid]

Angling / hook damage to mouth and especially gills can be significant and even life ending.  This not even require landing fish.  

 

Catch a hundred fish and place them in a low stress environment for recovery.  Less than 100 will be alive after 24 hours.

[Matt DeLaVega]

This depends largely on method.I fly fish mostly. I never deep hook fish. Fish with live bait lazily and you will kill plenty. Has more to do with the angler and fishing technique than anything else. However barbless hooks will also work in favor of the fish. I do this very often. Catch fish out of my pond and transfer them into a 7 hundred gallon tank right next to my pond and have near zero loss. It would probably be quite different if I used live bait and napped while fishing.

[centrarchid]

Use jig sleepy head and repeat.

[Betta132]

I've hooked fish and brought them home for aquariums a couple of times. The only time I lost them was when I brought home blacktail shiners that were a bit too large, and I'm pretty sure that was stress (big ones can't handle stress well at all, I didn't know that at the time) rather than hook damage, as they each only had a pinhole mark each. I've also kept a total of 7 sunfish, all caught on barbless hooks without live baits, and none of them have died after capture or even come close. The puncture mark heals quickly, and none of them even have visible scarring. 

As for stress, a good catch probably isn't any more stressful than a chase by a semi-persistent predator. Hook fish, haul it in as fast as possible, plonk it in a bucket of water for any inspection and for hook removal, and immediately put it back when done. Even when I take a picture, the entire thing lasts maybe 10-15 seconds, and I've seen predatory fish stalk an area and terrorize prey fish for longer. Maybe they aren't being chased the entire time, but they are being threatened very intensely by something that absolutely wants to eat them. Fish in buckets seem more confused and upset than outright terrorized, too.

Edited by Betta132, 10 April 2016 - 12:12 PM.