Can you Burp a Trout?

“Can you Burp a Trout?”

Most fish have swimbladders and use them to regulate their buoyancy, like a Buoyancy Compensation Device (BCD) used when SCUBA diving. There are two major types of swimbladders, physostomous and physoclistous. Physostomous swimbladders are inflated and deflated via the gut, so fish must gulp air from the surface to inflate it and pass air out the mouth or vent to deflate. Physoclistous swimbladders are inflated and deflated via the circulatory system.

Trout and all other Salmonids have physostomous swimbladders, which means you can burp them (if necessary). You may be asking ‘Why would I ever want to burp a trout?’ But this can be important information to know if you are fishing in deep water. Fishermen who have trolled deep in lakes for lake trout (or touge) have likely experienced fish with an over-inflated swimbladder. When trout that are hooked in deep water and brought to the surface quickly, gas held within their swimbladder rapidly expands from the decrease in atmospheric pressure. It often expands so large that the fish are unable to expel it. When you release a fish with an over inflated swim bladder they must fight their way back down to a depth of appropriate pressure. However, fish tired from fighting and released into often warmer (summer) surface waters, do not have the energy to do so and will die if not attended to.

Fly Fishermen rarely encounter this problem because they fish in shallow streams where the pressure changes are minimal. However, this can mean life or death to fish if you happened to be fishing deep. While on one of my annual summer fishing trips I found myself in this very situation. I was on the hunt for Brook Trout and Landlocked Artic Charr (Bluebacks) in the deep ponds of Northern Maine. The fish were holding around deep grass beds and would begrudgingly take heavily weighted nymphs and very small streamers.  I anticipated potential over-inflation problems from fish pulled from deep depths and prepared a deep-water release system.

Deep-water release can be used as an alternative to burping a Trout. It requires less handling than burping, which makes it a whole lot faster. I simply tied my thickest tippet to my metal landing net. I would land a fish with the net, snap a quick photo, and gently lower the fish and net back down to the murky depths. I would slowly lower it until I touched the bottom, hold it there for a second, and then slowly bring it back up to the surface. The fish, most likely, gained balance and left the net long before reaching the bottom, but better safe than sorry.

If you do find yourself in a situation where you need to burp a Trout, here is how to do it. Starting at the tail end of the fish, hold this fish between your thumb and fingers, and slide your fingers forward gently applying pressure. You should be able to hear the release of air. Burping a trout should only be done as an absolute last resort.  Many fish, if not played too long and released quickly, can make it back down on their own. If you are fishing deep you might as well have a deep-water release system in place for minimal handling and speedy releases. However, if a fish is struggling and is unable to make it back down to the cold deep waters, burp her as a last resort. Keep in mind a burped fish is going to lack the appropriate buoyancy control at its desired depth and therefore must endure more stress, but gives them their best shot.

Note: Keep in mind you can only burp fish with physostomous swimbladders. More advanced fishes such as Largemouth Bass, Smallmouth Bass, and other Sunfishes are UNABLE to be burped.  

Stephen Knott

TheLadyGreyFlyFishing.blogspot.com