Rockfish caught in deep water often sustain injuries referred to as barotrauma. All rockfishes possess a closed swim bladder (a gas-filled organ that regulates buoyancy). When fish are brought up from depth, decreasing pressure allows the gas to expand which may cause injury and make it impossible for the fish to return to the bottom. When captured in deep water (>100ft), symptoms appear immediately lethal. However, if recompressed, immediate symptoms appear to resolve and many fish swim away.

Visible symptoms of gas expansion include a swollen and tight belly, stomach protruding past the gullet and into the mouth, and distended and/or "crystallized" eyes. Miraculously, many rockfish can recover from barotrauma if they are properly released to their respective depths as soon as possible.

Anglers can also make their own deepwater release devices out of simple leadhead jigs. The device should weigh at least 3 pounds in order to submerge a large rockfish. Note line attached to hook bend to facilitate deep release. Also, a barbless hook is used to facilitate release. Have device assembled and ready to use before you start fishing. Consider dedicating an old rod and reel or downrigger for this purpose.

Commercial fish descenders: There are a variety of practical and easy to use fish descenders on the market. The best one for you may depend on the sizes and species you catch.

Proper Deepwater Release

Rockfish are most likely to survive when released quickly at depth by anglers using the following steps:

Step 1:

Make sure your release device is ready, rockfish are most likely to survive when time at the surface is minimized. With practice, rockfish can be released within two minutes of reaching the surface. Reel the fish up as quickly as possible. After unhooking it, hook the release device through soft tissue on the lower jaw. Make sure the hook does not have a barb. Release the anti-reverse on the reel so line can spool out freely.

Step 2:

Swing the fish slightly to one side and let go of the jig. Let line out as the weight pulls the fish back to the bottom. When the jig hits bottom, lock the reel and give a hard tug to release the fish.

Another method is to use an upside-down milk crate, weighted and attached to a rope: Crate is dropped over the fish and then, with the buoyant fish inside, lowered to a minimum depth of 60 feet and kept down until it can swim out on its own. Caveats: In rough seas, fish can escape prematurely and the crate may bang against a fish's extended eyes. Try lowering the fish down gently or paint crate's inside with a rubberized coating to smooth sharp edges.

DO NOT vent or "fizz" rockfish! Venting or "fizzing" involves puncturing the stomach protruding from the fish's mouth, or puncturing the fish's body to let air out of the swim bladder. Anglers not encouraged to pratisc venting as it can cause serious injury to fish and angler. You may accidentally puncture the wrong organ and/or introduce infection. Even when done properly, venting damages a fish's swim bladder. This practice can lead to infection in the body cavity and eventual death.

Proper deepwater release techniques can reduce mortality. A recent Alaska Department of Fish and Game study found that survival of yelloweye rockfish released at depth was far higher (98 percent) than survival of fish released at the surface (22 percent).

Fish Release Weight - Barotrauma