Blog And Tips -

How to Use a Fly Fishing Indicator

picture of a fly fishing bobber in the water

Every angler calls their indicator by a different name. For some it’s the bobber, flotation device, strike indicator, nymph suspender, or just plain indicator which is what I call them. Fly fishing with an indicator makes the world of a difference when fishing with nymphs, midges, and emergers.  


3 main uses for a strike indicator

I have probably lost more fish to not setting the hook at the perfect time than to anything else. These indicators are extremely effective, the whole idea behind the indicator is for three different reasons. 

  1. The indicator gives the angler a visual clue of when a fish has struck the fly. 
  2. It serves as a depth regulator.  
  3. The indicator can keep your fly positioned in a particular area. 

If you are newer to fly fishing, you may think that fly fishing is all about placing a fly on the surface of the water. That is only part of fly fishing, the rest is under the surface. Fish eat more below the surface the on the surface. This is because the deeper the fish are, the more protection they have from predators. Also, there are larval, nymphal, and pupal stages of insects in the water that the fish forage on.  

Anglers need to mimic these below surface insects in order to catch more fish. Tying an indicator to your line will make it so you can place your hook at an exact depth in the water. Whether that is 6 inches from the bottom, or 9 inches from the surface, wherever you think the fish are biting, you can place your fly there. 


Deep water. 

If you are fishing in deep water, you may way to use a quick release style of indicators. You don’t want to be reeling in your line and your indicator hits the top of your rod making it impossible to keep reeling. A quick release indicator will automatically slide down the line if there is tension placed on the line from a fish taking your fly. 

When using an indicator, you will want to be using a fly with some weight to it. This will help sink the fly and the line to your desired depth more quickly. 



We all know that casting is one of the trickiest parts of fly fishing. Casting with an indicator on can be a little troubling, especially when it comes to which style of indicator you are using. I spent many hours untangling the knots that indicators caused.  

Tangling can be avoided if you slow your cast down. Slow and wide movements are best. The larger the indicator, the more difficult they are to cast with.  


Styles of Indicators. 

Indicators come in many different forms nowadays. Cones, Corks, Styrofoam toothpicks, sticky foam, Air-Locks, yarns, plastic pegs, and whatever else you can attach to your line. They all serve their purpose for the specific situation in where they are used.  

Let’s go over some of the different indicators that are on the market today. 



cork bobber

I am guessing that some of the first indicators fly fishers used were made of cork. I am personally not the biggest fan of them due to the difficulty of securing them on your leader. You will often have to cut your leader afterwards. 



picture of a yarn indicator

Yarn indicators are widely used today due to their heightened sensitivity when a fish strikes. The weight seems to flow well with the fly line and leader making casting a walk in the park. They usually come in bright colors that make them easy to spot. The way the yarn indicator lands on the water is very smooth as well. You will often need to apply floatant to your yarn indicator. 


Poly Yarn indicators are also used by anglers around the world and mainly in New Zealand. These indicators are similar to the standard yarn indicators. They are often trimmed using scissors to get the exact size the angler is looking for. I personally am not a fan of yarn indicators because they tend to sink if you are using heavier types of flies. If your indicator sinks, it defeats the entire purpose. 



picture of a thingamabobber

Thingamabobbers are plastic hollow balls. They blew up in popularity because of their simplicity. New anglers could easily tell when they had a fish on, which led to landing more fish in their nets. They are easy to apply to your leader, but they tend to leave a kink in your line after use. 



picture of foam indicators

Foam indicators are nice for casting and their sensitivity, similar to that of the yarn indicators. To apply a foam indicator, you fold it over your line, and it sticks together like a sticker. If you need to add more because you are using heavier flies, it's very simple. The foam indicators do tend to fall off and because of that, I am not a fan. Keeping our rivers clean is every anglers responsibility. There are different types of foam indicators that work great as well and they are applied like the yarn or Airlock indicators. I would suggest using these styles over the sticker type. 



picture of airlock indicators

The Airlock indicator is the new and improved Thingamabobber. The more time I can spend fishing and the less time I can spend gearing up the better. The Airlock indicators save me time, giving me more time to catch fish. The small end twists off, then you place your line in the small groove. After your line is in the groove, you twist the small end back on. You will want to twist it tightly, so the indicator does not slide up and down your line. If you twist the little nut on too tight, it can kink your line. 

Casting with these ¾ inch indicators is a breeze and the bright colors help me to see it when the sun is hitting the water blinding me. The white indicator is great if you are fishing in extremely clear water making it harder for the fish to spot.  



Does size matter? 

Let’s stay on the topic of fly fishing here... If you go too large with your indicator, it will make it hard to lift it off the water when you start your cast. It may also slow down the natural drag of your line making it not seem natural to the fish.  

Another reason we don’t want an indicator that is too large is for when it hits the water. We do not want to scare the fish away. The smaller style will land softer. 

Remember, presentation is everything when fly fishing.  


There are other indicators out there as well for the more advanced fly fishers, but these seem to be the most commonly used. Bobbers have come a long way and are part of the reason why we see more people fly fishing these days. The most important thing to watch for when using indicators is tangling. After a few days of casting, you should have it down! 



If you like reading about fly fishing, our Zinger Fishing blog has a wide variety of different articles. We cover places to fish, what patterns to use, techniques, gear, and everything else to help fellow anglers land more fish in their nets.