Mop flies—some anglers love them, and some anglers hate them. The controversial fly was invented in the 90s by Jim Estes, and it has grown in popularity ever since. In its current form, it’s even been banned from several fly fishing competitions for its effectiveness. Regardless of your opinions, there’s no denying these flies catch fish. Tied with microfiber mop tassels, it’s not quite clear what they imitate and why they work, but they do.
While known as a trout fly, one angler, Trevor Johnson, Global Sports Marketing Specialist at Costa, is testing the limits of what a mop fly is capable of. His mission is to catch as many species on mop flies as possible. He’s taken his collection of mops to rivers, lakes, and now the salt in hopes of checking off new species. Recently, we sat down with Trevor to learn more about the “Mop Fly King” and his journey into fly fishing’s most controversial fly pattern.
Flylords: When did your obsession with mop flies start?
Trevor Johnson: My obsession with mop flies began when I was a fly fishing guide at the Blue Quill Angler in Evergreen, Colorado. I was constantly experimenting with new patterns to put more fish in the net for my clients. A few of my coworkers had fished in the fly fishing world championships and told me about a jig-style mop fly pattern that got banned from competition for being too effective.
They gave me one to try, and on my next guide trip, I put it to use. My client was new to fly fishing and caught seven rainbows and browns in a short amount of time. After that, I was sold. I started tying my own renditions, chasing new species, and became infatuated with mop flies.
Flylords: Where did the idea of catching as many species on a mop fly come from?
Trevor Johnson: I had been fishing the mop fly almost exclusively for trout on a 10-foot 3-wt and had been doing well with it. One day, on my way back from the Eagle River, I stopped at a pond on the side of the road and, rather than re-rigging, took the mop down to the bank. It was the only rod I had on me, so I figured I’d just try it and see what happens. It didn’t take long for me to catch a bluegill, a largemouth, a catfish, and a carp, all on the same mop fly. After that, I realized just how effective and versatile a pattern it was and started to target as many species as I could.
Flylords: How many species have you caught on mop flies so far, and what has been the most challenging?
Trevor Johsnon: I’m currently sitting at 12 species caught on the mop fly across saltwater and freshwater. The current list includes brown trout, rainbow trout, cutthroat trout, common carp, white sucker, channel catfish, bluegill, largemouth bass, smallmouth bass, tilapia, peacock bass, and tarpon.
By far the most challenging was the tarpon. It was a juvenile tarpon, but still, it gave me a run for my money. First, tying a mop that actually imitates something a tarpon would eat was tricky. On top of that, once I hooked one, getting it to the boat was no easy task.
Flylords: What is your favorite species to target with mop flies?
Trevor Johnson: Hands down, my favorite fish to target would be carp. They are notoriously picky and can be spooky, especially in heavily fished waterbodies. I’ve found that by modifying the mop flies I tie, I can get them to eat in clean or dirty water conditions, all depending on how heavy the fly is. I’ve got an arsenal of them in my carp box in every size, weight, and color you can imagine. If I could only choose one fly for carp, it’d be a mop.
Flylords: Are you tying your mop flies to imitate anything specific, or are they more attractor-style flies?
Trevor Johnson: This is probably one of the biggest questions when it comes to fishing mop flies. For trout, I think they best imitate a crane fly larva or other grub-like food source. Natural colors like cream, tan, or brown can be great natural imitations.
On the other hand, when fishing for other species, the mop becomes much more of an attractor fly. It’s all about the way you strip, retrieve, drop, or jig the fly. You’re trying to trigger a predatory response, so that is where the mop becomes more of an attractor-style fly. Take tarpon, for instance; nothing they naturally eat resembles a mop fly. They often eat bait fish, so getting it out in front and two-hand ticking the fly resembles a fleeing bait and has triggered predatory strikes for me.
Flylords: What do you think makes the mop so productive?
Trevor Johnson: I think it’s the movement of the mop that makes it so productive. The profile covers a lot of the bases, like grubs, crane flies, or baitfish. Then you add movement to it, and you get a versatile pattern that you can fish in almost any way.
I also like to tie my mop flies by threading the mop on the hook, almost like a soft plastic swimbait. Most guys will just tie it to the hook shank, and while that works, my method reduces the amount the mop will fowl on the hook.
Flylords: What do you look for when buying mops to tie with?
Trevor Johnson: I typically buy mine on Amazon, but you can get them at auto parts stores, Walmart, and even some general stores. You want to look for car washing mitts with microfiber tassels. They come in almost every color imaginable, but a majority of the time, I’m fishing tan. From there, I’ll tie patterns in various weights to cover all parts of the water column. One thing I’d like to add is the dubbing loops I create, the dubbing colors, and the use of CDC on the collar. I’ve also started to play around with EP shrimp brushes for the collar.
Flylords: Are there any particular challenges that you face in saltwater mop fishing versus regular mop fishing?
Trevor Johnson: I think it’s going to come down to size. A lot of times, the size of the mop that I’m tying is a size four or a size two. In saltwater, a lot of these larger fish aren’t going to typically go for something that small, especially if it doesn’t have the profile of what they’re feeding on, like a snook. You’ve got to get creative when it comes to tying saltwater mops to imitate what the fish are feeding on.
Flylords: What tips would you give to someone who’s never fished a mop fly before?
Trevor Johnson: Throw it on and watch the magic happen. The mop is one of those controversial flies, like a squirmy worm, that just works. I remember struggling to catch my fish on my own until I tied on a red San Juan worm and caught my first trout. The mop fly is very similar. It’s not fancy, it’s quick to tie, and it works. If you can get a good presentation in front of a fish, chances are they are going to eat it, and that’s why I love it (so much so that I even have a mop fly tattoo).
