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just wondering on what teckniques there are for popping swim bladders of fish caught in deep water and what effect this has on the fish. some people pop the bladder in the mouth some people pop the bladder just behind the front fin.
Just wondering on other peoples thaughts and if people know what affect this has on the fish?.
Dylan
The prefered method these days is to count back along the dorsal fin to the fourth or fifth spine, come down to about level with the pectoral fin and insert a thin, sharp hollow tube.
Another method is to spike them up just in front of the anus on an angle. Apparently the method of spiking them through the mouth is far more prone to infection.
Puncturing the swim through the mouth will more than likely kill the fish when it swims back to the bottom,water will find it's way into the cavity behind the blader due to the presure,I've read this causes peritinitis.Agnes Jacks two methods are the only acceptable ways that will give the fish a better than even chance of survival.
That thing sticking out of the mouth is not the swim bladded but the stomach, turned inside out. Puncture it and you will definitely kill the fish. The coreect method is the thin tube system. But if the water is deep, the bladder pressure in the body cavity has already stopped the heart, by squashing it flat, and the fish invariably suffers the bends before it hits to surface. With the heart stopped circulation stops, the fish gets deep into respiratory acidosis, and the blood pH drops drastically. Not very nice, but the effects are less with small fish than they are with larger fish.
The best method of release is to take you time bringing the fish up, allow it time to
decompress. I know it takes a while, but the fish will probably suffer lower pressure effects and maybe survive. You can release fish with lead weights, but that does not stop the effects of circulation stop, the acidosis and the bends.
The pressure down there is pretty high, and swim bladders have to be pretty well expanded to cause the stomach to come out of the mouth. Max
Rexy and co. were popping the bladder (stomach???) with a knife into the mouth last weekend, catching black jew from 50m at Melville Island...seemed like a fairl new episode as well...Makes you wonder...
G'day all
There is currently a research project underway in Queensland dealing with the post release survival of several reef fish species. There is more info available at the link below. http://www.dpi.qld.gov.au/far/13522.html
Agree with Agnes's views.
Are the Spike tubes available from reputable Tackle shops?
Can't say I have seen them,but hey i'm like a kid in a chocolate shop when I go thru those doors.
Lures,line,tackle,rods,reels,knives;what did I come in here for? [smiley=hammer.gif]
i've heard of ppl lightly hooking them with barbless hooks (for easy escape) then sending them down slowly on a handline and leaving them. Once you stop their descent they wiggle about and free themselves apparently - hopefully enough pressure down below to equalise.
The practice is to use a special lead weight which takes the fish down. It is connected to the fish with a barbless hook, like in the pic. This works particularly with smaller fish from medium depths. The problem with these release methods is that from deep water, by the time you get the fish up the circulation has been stopped for quite a while and the fish cannot get oxygen into the blood, and uses what it has and this starts the respiratory acidosis and the pH problems as well as CO2 gas bubbles expanding in the capillaries which eventually burst the things and the fishes mostly expire. There is a release mortailty rate, fishes do die from stress and pressure problems. The question is, how many, and thats debatable. I think we should be more careful about release, and be particularly mindful of stress from removing from the water, handling, light strike on unprotected eyes, and a lot of other problems that some people have a deal of fun with on TV programs. My personal view is that TV kills more fish than the bloody programs are worth.
I have a ongoing battle with Garry Lilly, Westag on this, the pic is one of his, and I think we have agreed to disagree, but I do agree with him that release knowledge out there is pretty bad, and more education is necessary, from the top down.
I'm not in favour of bream contests, because of stress, and tuna contests because tuna are particularly susceptable to energy burnout and lactate buildup.
Actually I wish people just released fish in the water without touching them at all. Max
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