TPWD News Release — Feb. 2, 2011
ATHENS—The Inland Fisheries Division of Texas Parks and Wildlife Department (TPWD) today announced the availability of a seven-minute video detailing the results of a two-year study to determine the best method of treating largemouth bass suffering from barotrauma.
“Barotrauma refers to an overinflated air bladder,” said TPWD Inland Fisheries biologist Randy Myers, who led the study. “A fish’s air bladder inflates and deflates to enable the fish to suspend at a particular depth. Fish that are caught and brought to the surface are suddenly under less pressure. If a fish is released immediately, it will usually have enough energy to swim back down to the depth it was caught from.”
Fish caught in tournaments are particularly susceptible to barotrauma, Myers explained. “Fish caught in tournaments are typically held in a livewell for several hours before weigh-in. After a few minutes at the surface, the air bladder can expand to the point the fish is unable to submerge. The overinflated air bladder presses on vital internal organs, and the fish’s stomach may protrude from its gullet. The fish becomes exhausted from trying to submerge and floats on the surface, where it may die or be injured.”
Organizers of several bass fishing tournaments allowed Myers to use fish caught in tournaments to train a number of TPWD employees how to use a needle inserted into a fish’s air bladder either through the mouth or the side to release excess air. This procedure is commonly called fizzing, since the air released from the bladder makes bubbles in the water.
Myers then conducted a study on fish collected by electrofishing. Fish were fizzed through the mouth or side by trained personnel, by untrained personnel, and not treated at all. “We wanted to determine if fizzing results in greater survival, and if so, whether fizzing through the mouth or the side was more effective,” Myers said. “Our study proved that side fizzing resulted in the survival of 14 percent more fish than mouth fizzing.”
Myers used Lake Amistad as the site for training and study. “Amistad has a lot of bass tournaments, and 50 percent of the fish weighed in at those tournaments suffer from barotrauma,” he said. “Increasing the survival rate of those fish makes a significant difference.”
The video, entitled “Treating Barotrauma in Largemouth Bass,” was shot in high definition and uses a dissected bass to show the locations of the air bladder and internal organs that can be affected by mouth or side fizzing. Myers also demonstrates the proper technique for side fizzing, including how to locate the needle insertion point and how long to release air from fish of different sizes.
“Tournament organizers and anglers have long been practicing fizzing and were very helpful during the study,” Myers said. “However, no one had ever determined which method of fizzing was best for the fish. Our goal was to provide a scientific basis for the practice and show anyone interested the best way to fizz a fish.”
The video may be viewed on TPWD’s YouTube channel at http://www.youtube.com/watch?v=pEeQrsHcwf8. TPWD encourages anyone with a web site to link to that page. Broadcast media or others wishing to download the HD version from TPWD’s FTP site may obtain instructions for doing so by sending an e-mail to Larry Hodge at firstname.lastname@example.org.