Don’t Be Stumped, Try Your Pump | A Guide to Pumping Fish Safely

Don’t Be Stumped, Try Your Pump | A Guide to Pumping Fish Safely

Why leave the river feeling stumped when you could have pumped?

Using a stomach pump is a very controversial subject among fly fisherman/women. Walking up to the register of a fly shop with a stomach pump in hand will likely land you more dirty looks than a whore in church. They are usually located near the spin fishing gear section, aka the”red-light district”. Guides often joke about having pumps in stock at the shop for profiling purposes only. But the best guides I know all carry stomach pumps, and for good reason.

We have all had those hair-puller days when for example; you catch a couple fish on your attractor nymph (San Juan, egg, Pat’s Rubberleg, etc.), but you know if you could have matched what they were dialed in on you would have crushed them. Or there may be a blanket caddis hatch but the fish are gorging on BWO emergers below the surface instead. The stomach pump is one of my most important and valued tools for such situations. When used properly, a stomach pump will give you the advantage of knowing what you should be tying on instead of the old “guess, check, and repeat” technique. The less you have to change flies, the more time you spend fishing, further increasing your odds.  In some ideal cases the stomach contents will show exactly which bug trout are keyed in on. Even if the stomach contents contain a variety of bug species, the bugs will most often be of the same size or color. Most important is the knowledge gained over time by finding patterns of relationships between stomach contents and the fishing conditions, i.e. (season, water/air temperature, barometric pressure, moon phase, etc.).

Where I Stand on the Pumping Controversy 

Is pumping ethical?
– No, it is not “ethical”. But by definition any sport fishing practicing catch and release is not ethical. I say get over the ethics stigma. We are not ethical by nature, we test our drugs on animals, eat genetically modified meat raised under terrible conditions, and we even expose the planet we live on to deadly pollution for Christ’s sake! Pumping a trout’s belly is not an ethical issue for me.
Can Pumping harm trout?
– Absolutely. You should know how to use the pump before trying on a live fish. Never pump a fish under 10 inches or over 18 inches. Never try to pump a trout more than once and never pump an exhausted or injured fish. With that said, pumping causes far less harm to a trout than most other human  interactions such as big barbed hooks, improper handling, or swallowed lines/hooks.
How To Properly Pump a Trout
1.) Lubricate the outside of the tube with water. Turn trout to its side or upside down if possible. With the tube empty of water, squeeze the bulb half way shut, then insert the tube into the gullet. Release the bulb to form a vacuum seal. Make sure not to push the tube into the back of the stomach.

stomach pump

2.) After forming the vacuum seal, steadily remove the tube from the gullet. When the tube exits the gullet the bulb will expand and suck some stomach contents up into the bulb.

stomach pump

stomach pump

3.) Slightly depress the bulb and suck up some water into the bulb. Squeeze contents into a container or your hand. Make sure to let the fish fully revive before release. Thats all there is to it!

stomach pump

stomach pump
Sample from Yampa River, CO Rainbow showing a high quantity of newborn scuds.

stomach pump
Sample from a Davidson River, NC Rainbow showing a wide variety of bugs.

Stomach Pump Results

It’s time to nail down your 2024 fly fishing trip with Minturn Anglers.

About the Author

Justin Nolan

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