The fishing was slow and trout were skittish. I’d caught two rainbows but missed a handful of others, mainly because the bite was so subtle that they shook off before I even realized they were on the hook. I took a break to ponder the situation and noticed a plastic package half-covered with fallen leaves on the streambank. Although the package was almost empty, there were still a couple of pink plastic foam pads inside. I pinched one onto my line about two feet above the nymph I’d been using and my day took a dramatic turn for the better. All of a sudden, all those misses started turning into catches.
That was over 20 years ago, but that day was a landmark moment in my fly fishing career. I’d read about strike indicators prior to then, and like other critics, I’d brushed them off as “glorified bobbers.” I envisioned myself a fly fishing purist, after all, and the idea of putting a bobber on my fly line seemed blasphemous. Now, after realizing how effective they are for fishing nymphs, I gladly tie one on.
The original strike indicators were attractor-style dry flies fished with droppers, and they’re still a good option today. Big, gaudy flies such as Stimulators, Humpies, and Royal Wulff’s generally work best because they’re durable enough to support the additional weight of the nymph. They’re also the most visible. The added bonus is that you have another fly on the water that might spark a trout’s appetite, which gives you two chances to catch fish.
There are times, though, when casting a dry fly-nymph combination might not be ideal, such as when I’m fishing fast, deep water or fishing big nymphs for big trout. In both instances, I prefer a nymph tied straight to the leader or tippet because both can put a strain on your tackle, and fewer knots means fewer things that can go wrong. Also, I occasionally prefer to just fish nymphs and don’t want the extra hassle of tying on a dry fly and then attaching a dropper. In those situations, I use one of the many varieties of strike indicators on the market.
Sometimes a manufactured strike indicator can spook fish on waters where trout see a lot of them. I equate it to highly-pressured whitetails that have a tendency to look up in an attempt to spot the silhouettes of hunters in treestands. Finicky trout can display the same traits, so you’ll need an indicator that accomplishes its purpose yet goes unnoticed.
Strike indicators come in a wide variety of styles and colors. I opt for the smallest indicator I can get away with that will still support the nymph. If the weight or drag of the nymph is pulling the indicator underwater, bump up one indicator size.
Color can play a major role in how trout react, too. Although orange and pink are the most visible, white or off-white are usually better options. In nature, white objects often end up on the water – bird feathers, dandelion fibers, plant matter, etc. A white indicator appears no different than objects they see on a daily basis anyway.
A good gauge as to whether your indicator is working or detracting from your success is observing how fish react as it passes overhead. If they dart around the pool or even slash at the indicator, you know your indicator is drawing too much attention and you should switch to something more subtle.
The first strike indicators I ever used were plastic foam pads that had adhesive on one side and pinched onto your leader above the fly. They’re still a simple, easy-to-use product, but they have disadvantages. Once in position, they can’t be moved, and if you do decide to take them off, they usually leave a bit of sticky residue on the leader. That might not sound like a big deal, but throughout the course of a day, I fish a variety of water depths and current speeds, which requires a lot of adjustments. On an all-day excursion, I can burn through a lot of that style of indicator.
Which Indicator to Use?
Nowadays, I prefer reusable strike indicators. Depending on the brand, a package of three usually costs about the same as a handful of quality dry flies, and some of them will last multiple seasons – or until they end up in a fly-grabbing tree. Airlocks, Thingamabobbers, Tipper Strike Indicators, and Whitlock’s Telstrike Indicators are all good options that I carry with me.
Strike indicators are great tools for fly anglers. Pictured left to right: Thingamabobber, Whitlock’s TelStrike, pinch-on style indicator, and Tipper Strike Indicator.
Synthetic poly yarn tied to the leader works as an inexpensive indicator, too. The advantage of the synthetic poly yarn is that it can be colored and trimmed to fit the conditions. They’re also extremely sensitive and allow for a soft presentation. Bigger, bulkier indicators that land on the water with a plop can spook wary fish.
I treat my yarn-style strike indicators with fly floatant. This helps them ride higher as well as makes them easier to lift up off of the water when setting the hook or preparing to make another cast.
Placement of the indicator on the leader can be a conundrum. You want enough distance between the indicator and nymph so that the nymph bounces along the bottom, yet the closer the indicator is to the nymph the better you’ll be able to detect strikes. Usually I settle on whatever the average depth of the pool or run happens to be. If my fly never bumps the bottom, or I don’t snag the bottom at least once in a while, I set it deeper.
Detecting strikes can be challenging even when using an indicator. Trout are constantly in motion, sucking in and spitting out debris in a fraction of a second as they test its texture to determine whether or not it’s food. In the same manner, they can inhale and exhale a fly before the sensation even travels up the line to the indicator. Even once they take the fly, there’s always a slight delay before the action is transmitted up the line, so your reaction time is important. A quick hookset will land you more fish.
Strike indicators require complete concentration. If I see the slightest bit of hesitation or erratic movement with the indicator, I set the hook. Even if it’s a false alarm, and my indicator paused because my fly scraped the bottom, I’d rather set the hook and have nothing than not set the hook and miss a fish.
Indicators take a lot of the guesswork out of strike detection. They’re one product that can almost immediately make you a better nympher. They’re more than just a bobber, and they can turn a frustrating outing of missing fish into a day of catching that you’ll never forget.
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