Why Do Trout Eat Purple Flies?

Fly fishermen preach, “match the hatch“—the process of exactly mimicking natural insects to fool a trout. With an endless amount of fly tying materials and new ones coming out each year, anglers can match their flies to the exact size, color, and profile of the naturals. As fly patterns get closer to the natural bugs, it would make sense that anglers catch more fish, right? Yet, if you looked through a random angler’s box, chances are you will find loads of flashy, gaudy attractor fly patterns. Of these flies, purple flies are some of the most vibrant and unrealistic patterns that consistently fool trout. Patterns like the purple haze, J’s purple nurple, and Egan’s purple dart are found in boxes and fly shop bins across the country. So why do trout eat purple flies?

Why Purple Flies Work

Just as humans see color in different wavelengths, so do trout. The difference is what wavelengths they actually see. This stems from trout having four color receptors in their eyes as opposed to the three in our eyes. As a result, the color receptors pick up wavelengths differently. For instance, what we perceive as dark red, trout perceive as bright red. The same is true for purple. 

Trout sees shades of blue best, followed by shades of red, and lastly, shades of green. The color purple falls somewhere between blue and red and shows up as a flashy hotspot. This draws a trout’s attention, making purple an effective fly color.

When to Fish Purple Flies

Since purple flies show up as a hotspot to trout, it’s important to know when to fish them and when to match the hatch. Discerning between the two will result in more fish landed.

Dry Fly Fishing:

if you are lucky enough to stumble upon an epic hatch and trout poking their noses through the surface film, choose your fly carefully. Now is not the time to fish purple. The trout are keyed in on the natural bugs, and your offering should reflect that. Match the size, color, and profile as closely as possible. The trout know what they are looking for, and your fly should imitate the naturals.

Purple flies are a great choice when you find yourself fishing without any hatch. Serving as attractor patterns, purple flies get the attention of trout that may not be looking for a particular bug. These work exceptionally well during warmer months and should be fished along shallow banks where trout are likely sitting. The bright glow a trout perceives from a purple bug can work wonders for drawing surface takes when prospecting.

Subsurface Fishing:

In general, purple flies are great subsurface attractor patterns. Fished as nymphs or streamers, they can consistently draw strikes. However, there are scenarios where purple flies work best. As the water depth increases, the amount of light that penetrates the water decreases. This results in changes in the way trout view color. For deep pools with low light, purple is one of the few colors that trout can readily pick up on. As a result, when fish are congregated in slow, deep pools, purple should be a confidence color.

Purple Flies to Try

You can tie any pattern in purple to attract trout. That said, there are a number of well-established purple flies or purple variations available. Here are some of our favorites.

Dry Flies:

1. Purple Haze
2. Naked Chubby – Purple
3. Bionic Hopper – Purple
4. Galactic Ant – Purple
5. GT Triple Double – Purple
6. J’s Purple Nurple Dry Fly

Nymphs:

1. Olsen’s Purple Blowtorch
2. Darth Baetis – Purple
3. Perdichingons – UV Purple
4. Zebra Jig Thin – Purple
5. Higa’s SOS Purple

Streamers:

1. Bloom’s Zirdle – Purple
2. Galloup’s Barred Micro Dungeon – Black/Purple
3. Galloup’s Menage a Dungeon – Purple/Black
4. Balanced Leather Leech Nano – Purple
5. Baby Complex Twist Gray & Purple

5 Best Trout Streamers for Fall Fishing

15 Best Flies for Winter Trout