By Greg Stover
The University of Florida IFAS Extension and Florida Sea Grant held a webinar on September 11 detailing the latest findings on barotrauma and methods of addressing barotrauma for reef fish that are to be released. A recording of the webinar can be viewed by clicking here.
Barotrauma is a condition caused from the expansion of gas in a fish’s swim bladder during capture due to changes in pressure as a fish is reeled up from deep water to the surface. Some signs of barotrauma include bloated belly, bulging eyes and the stomach protruding from the mouth. Many fish suffering from barotrauma become what fishermen call floaters, fish that can’t submerge because they can’t overcome the added buoyancy of their expanded swim bladder. (Read More)
Venting has been the traditional method of alleviating barotrauma. A long, hollow needle is inserted behind the pectoral fin and into the swim bladder to relieve the built up gas pressure. Proper venting requires some skill and proper tools, and if not done correctly can cause more damage than the barotrauma. Knives, gaffs and ice picks are not suitable venting tools. Regulations enacted in June of 2008 required the possession and use of venting tools on all vessels fishing for reef fish in Gulf of Mexico waters. Since then, scientific studies have raised questions about the practical effectiveness of venting fish. As of September 3, 2013, the possession and use of venting tools is no longer required for anglers fishing for reef fish in federal waters of the Gulf of Mexico.
Recompression techniques using descending gear are the latest trend in releasing deepwater bottom fish. Descending gear is a weighted device that holds a fish and carries it down to a depth that is sufficient to recompress the swim bladder and allow the fish to swim off under its own power. Studies in California have shown using descending gear results in high post-release survival rates for Pacific rockfish. Scientists are now studying similar recompression techniques in Gulf of Mexico and South Atlantic waters. The Florida Sea Grant webinar discusses several types of descending gear and includes videos showing their use.
For more information on the proper methods for handling, unhooking and releasing fish visit http://catchandrelease.org/.