![]() There are some problems with venting, though. When done correctly, venting can effectively allow those built-up gases to escape from the swim bladder, improving a fish’s ability to swim back down to the depths from which it came – and increasing its chances of survival. Venting entails the use of a hollow, metal tool to puncture the side of a fish’s body. Myth #3: Venting is the only option for treating barotrauma. It’s our duty as catch-and-release anglers to practice release techniques that will give the fish we love a better shot at survival – because even a tiny improvement in survival for deepwater fish can translate to millions of fish saved each year. Reef fish, especially the largest and oldest females that contribute the most eggs each year, are far too valuable to lose at so high a rate. That means nearly one in three fish in this study ultimately did not survive being caught and released. Another 13% of fish swam away, seemingly unharmed – but later died within 72 hours. A fish may swim away only to succumb to a predator on its return to the reef, for example.Ī study looking at barotrauma and survival in red snapper found that 15% of fish pulled from deep waters died immediately. Unfortunately, research has shown that barotrauma can have delayed impacts that anglers don’t always see. It’s a logical assumption that a deepwater fish that swims off with no apparent bloating or injuries has not suffered from its rapid ascent through the water column – no harm, no foul. It’s an amazing transformation from the bloated, stomach/swim bladder sticking out, eyes bulging to looking like a normal fish as the depth increases.Myth #2: A fish that swims away is in the clear. There are some excellent videos that show a rockfish going back to depth. Everyone who encounters rockfish that they will have to release because of restrictions, should be prepared with a device that gets that fish back down where it will survive the experience. These clip on to the jaw of the fish and using a pressure sensitive mechanism release you rockfish at your designated setting. Tom’s favorite is the SeaQualizer () made in three sizes for release depths ranging from 30 to 300 feet. There are a lot of devices made for this job. That’s why we now have a law in Southeast Alaska requiring sport fishers to deep-water release all demersal shelf rockfish that aren’t retained. If done properly, the release mortality goes from nearly 100% for effected fish released at the surface to something more like 20% or less according to some studies. It takes a heavy weight and a device that takes the fish down and releases it at the desired depth. In the past few decades a great deal of research has been conducted on deep water releasing fish with barotrauma issues. They are easily overfished, but having limits makes no sense if all the fish you release end up dead. Many species of rockfish are very slow growing and old. If you simply let it go, it bobs around on the surface until it dies from injuries or from birds pecking away at it. The air bladder pops out the mouth, bringing the stomach with it, the eyes bulge, the body appears bloated, and the fish has extreme positive buoyance, so much so that it cannot swim back down. When you bring that rockfish to the surface, the decrease in pressure results in an expansion of the air bladder so now it’s the size of a small party balloon. The swim bladder of a rockfish living a couple hundred feet or more down in the water column is under immense pressure and may only be the size of your thumb when inflated for neutral buoyancy. The purpose of the swim bladder is to provide the fish with something close to neutral buoyancy at the depth they live, thus they don’t have to work hard to simply hang suspended in the water column. This gases in the swim bladder are slowly extracted from the blood stream. In our fishing in Alaska, the principle group of fish that barotrauma applies to are rockfish which have a gas filled swim bladder.
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