Skip to main content

Fishing the Fringes

Big trout in side channels, braids, potholes, lagoons, oxbows, and tributary creeks.

Fishing the Fringes

Small water with large trout can be both challenging and rewarding. Trout tend to be wary of predators in these skinny conditions, but they are more willing to feed if you can be stealthy. (Cathy & Barry Beck photo)

This article was originally titled "River Detours" in the Aug-Sept 2018 issue of Fly Fisherman magazine.

Most fly fishers are explorers by nature. How many times on a new stream or piece of water have you wondered “what’s up around the next bend?” Or perhaps you come upon a small trickle of water that enters a larger river, and you wonder where it leads? Or you’re on a river like the Yellowstone, Bighorn, or the Missouri and you come to a side channel that looks inviting, but unknown. Do you take it, or go with the main flow? I encourage you to be a trout hunter and explorer. Walk up those small tributaries and take a look to see what’s there.

When you’ve spent most of your life looking for trout—either for yourself or with paying clients—you quickly learn to take advantage of whatever comes along. As a young guide, I spent most of my time on the upper end of Fishing Creek, my home stream, in northeastern Pennsylvania. There was a steel bridge just above a Boy Scout camp—Camp Lavigne—and my day started at the bridge. I often fished with my clients up through Long’s Farm then through Stauffer’s Farm, eventually ending up at a covered bridge spanning the creek. It was an all-day affair, and I covered a lot of good water.

Fly Fishing Side Channels, Braids, Potholes, Lagoons, Oxbows, and Small Creeks
This side channel on the Bighorn River offered protection from the wind, and slow water where Tricos collected on the surface. (Cathy & Barry Beck photo)

In those days, we found some beautiful wild brook trout and a good number of wild browns. There were a few really big fish, but what the trout lacked in size they made up for in beauty and numbers.

Less than 100 yards above the bridge a small braid of water trickled down over the bank and fell into Fishing Creek. One day a client and I got plastered by torrents of rain, and although the stream this far up rarely colored up, I could see the mud coming. Raingear in those days was not what it is today. Gore-Tex was years away, so we were soaked, and soon we were chilled. I suggested we walk back to the car to have lunch and warm up. As we walked back, the mud-laden stream rose and in a matter of minutes it was too high to fish. But when we walked past the small braids that had now become a small stream, it was running clear. We stopped and looked at it, and I asked my client if he would mind if I just walked up through the woods to check it out. I gave him the car keys, and started up the tiny tributary.

At first I found a series of braids that I followed for about 50 feet, and then up ahead I saw what looked to be the tail of a small pool. Due to the heavy rain and poor visibility, I walked right up to the tail of the pool, and immediately saw the wake of a fleeing fish. I knew I had made a mistake, so I headed for the car to allow the fish to settle down. After lunch, my client looked at the high, muddy water and moaned, “We’re done.”

Fly Fishing Side Channels, Braids, Potholes, Lagoons, Oxbows, and Small Creeks
Lagoons are places that flood during high water. Large trout take shelter in them during high-water events, and are later isolated when the water recedes. (Cathy & Barry Beck photo)

“Maybe not,” I replied. The rain began to slow as we approached the little pool back in the woods. This time we moved slowly, and then stopped well short of the pool to take a look. I was astounded by what we saw. Fishing Creek is a freestone stream, but this small lagoon was full of watercress and weeds, and reminded me of a spring creek from the central part of the state. Even with all the rain, there was hardly any current. “Look,” my client said, and I followed his hand to the upper end of the pool where we saw a rise form.

The water was as clear as tap water, but the light in the woods was horrible, so I tied on a #12 black Letort Cricket and suggested that we go slowly and blind cast, working our way up to the head of the pool. The first cast brought a 5-inch brook trout. We laughed, but it was a fish. A bit upstream, and four casts later, another small brook ate the cricket. Good, two fish to the net. Well, I didn’t actually use my net on those small fish, but still it was two fish.

We were almost to the head of the pool when the cricket simply disappeared from the surface. I yelled to set the hook, and in short order I used my net on a very healthy 14-inch wild brown. We admired the beautiful colors on the fish, and it disappeared in a rush when released. By the end of the day we had discovered three more pools that held fish. The last was the head of the spring where the water bubbled out of the ground. In the end we had 11 small brook trout and three brown trout.

Through the years I have found five other springs similar to the one on the Long property. All held fish, and I confess that I never found any really “big boys,” but they have saved my day on many occasions when Fishing Creek was not fishable due to high, dirty water. Most of the year, the pools were landlocked with no water running in or out, yet they were deep enough and cold enough to support trout all year. Sadly, the upper end of Fishing Creek itself has pH problems and the fishing has dropped off, but the little lagoons are still there and still have trout.

Lagoons, Ponds, and Oxbows

I use the term “lagoon” loosely here because lagoons in North America are most often associated with shallow coastal bodies of water that are separated from the ocean by land or a barrier reef. In Argentina, fly fishers and guides use the word “lagoon” to describe any body of water that is separated from a river except during flood stages.

Unlike side channels and tributaries, trout lagoons for the most part are landlocked. Most lagoons receive their trout from rivers when they have extreme floods. Trout are relocated during the high water, then are trapped when the water recedes. The best lagoons often have cold springs that help to keep the water temperature cold.


In New Zealand they merely call these places “small ponds.” Call them whatever you like, when you find large trout in these little places, you can create some incredible memories.

In Argentina, most major river systems have lagoons along them. The problem is often just finding them. Cathy and I were lucky enough to have some exceptional lagoon fishing with an American guide in Patagonia who was working for legendary angler Jorge Trucco. His name is Mike Poore, and his home base is Jackson, Wyoming. Poore was born a trout hunter, and his passion is finding large trout in out-of-the-way places.

Through our years of fishing with him, Poore showed us some of his favorite lagoons where we caught some humongous trout. Poore was a river guide, but on every day off he explored lagoons that looked promising. He fished in an arid area, so he looked for green willow trees that suggested moisture. He walked many miles, and more often than not, he found nothing. But every once in while he hit pay dirt. In the end, he mapped out the best lagoons along all the rivers he guided on.

One day we left our drift boat to hike in to a large lagoon. Along the way we saw what Poore called a pothole. It was a small, deep hole in the ground. There was green vegetation around it, so Cathy quietly crept up and made a cast with a foam beetle. The fly disappeared in a splash, and she landed a healthy 18-inch brown trout.

When she released the fish, we saw just how deep this little pocket of water was, and noticed a tree root at the edge of the water had a deeply undercut bank. The air temperature was in the 80s but the water in this pool was ice cold, and apparently influenced by an underground spring. If we hadn’t been with Poore, we probably would have walked right by it. Another lesson learned.

Side Channels, Braids, and Tributaries

Montana’s Bighorn River is one of our favorite Western destinations, but it has the reputation of being crowded.

Our favorite section of river is from the Bighorn Access to Mallard’s Landing. This lower section doesn’t see the same pressure as the upper 13 miles, and it also has a good number of intimate side channels.

Fly Fishing Side Channels, Braids, Potholes, Lagoons, Oxbows, and Small Creeks
Small tributaries are often the domain of small trout. A beautiful native brook trout or cutthroat in small water is a worthwhile reward in its own right. (Cathy & Barry Beck photo)

This past season we saw Trico hatches that seemed to bring up every fish in the river. We also ran into some wind, and on the main river the spinners quickly disappeared when the wind blew. By searching in the side channels, we found protection from the wind, and plenty of rising fish feeding in slow water where the Tricos collected. We just had to do a little searching.

The key to good side channels is cool enough water temperatures to support trout. In side channels, the amount of flow is critical. In high flows, big fish move into side channels for protection from flood current. When the water drops, they will stay to feed in small water if the temperature is cool enough and they are undisturbed.

Side channels at some point end up coming back into the main river. These junction pools are always worth exploring. A few years ago a bunch of my friends from Frontiers Travel along with Jorge Trucco and three of his guides did a float trip down the Limay River in Argentina. The Limay has a reputation for big fish below the dam. The weather was perfect, no wind, no clouds, warm, and there was very little boat traffic on the river. The morning produced a lot of nice fish on foam dry flies, and a few fish on large white tandem streamers.

We parked our rafts at a junction pool and decided to have lunch. The side channel to our right looked inviting, so while everyone in our party was enjoying a glass of Argentine wine, I picked up a rod and walked up the side channel.

The water was thin, maybe 2 feet deep, but it had potential. Ahead I thought I could see a shadow moving across the bottom. It looked way too big to be a trout, so I kept advancing. As the shadow got closer, I realized that it was a double-digit trout.

I quickly crouched down and looked at my fly. By mistake I had picked up a 7-weight Sage with a white tandem streamer. In this clear, low water I felt that my chances with this setup were little or none, but I made a cast anyway, leading the fish by 20 feet. I watched the leader and streamer sink to the bottom, and out of the corner of my eye I saw the trout charge. I never moved the fly, the big brown simply picked it off the bottom, and I set the hook. About 20 minutes later, and some distance downstream in the main river where my friends were finishing lunch, I landed the fish. Ten-plus pounds of Limay brown trout made a lot of smiling faces, especially mine.

Fly Fishing Side Channels, Braids, Potholes, Lagoons, Oxbows, and Small Creeks
The author caught this 10-pound brown trout by leaving the boats and exploring a side channel with insignificant flow. (Cathy & Barry Beck photo)

My point is that there can be a lot more fishing opportunities then just the main stream or river. Being willing to explore side channels—even if there is just a trickle of water—can sometimes pay off. Finding pools or lagoons cut off from the river can be more difficult, but good local guides often know these spots, and you can find them yourself if you’re willing to walk away from the river and explore.

I’ve had a lot of failures and disappointment when I risk my time to explore new places, but the excitement and satisfaction when things do work out makes it all worthwhile.

Cathy and Barry Beck are on the advisory staffs of Sage, Redington, RIO, and Tibor Reels. They are also travel hosts for Frontiers International. Their previous story, “When Caterpillars Fall,” was in the June-July 2017 issue and is now available at

GET THE NEWSLETTER Join the List and Never Miss a Thing.

Recommended Articles

Recent Videos

Learn to tie the Pheasant Tail Nymph with master tier Charlie Craven.

How to Tie the Useful Speed Blood Knot

Learn to tie the Pheasant Tail Nymph with master tier Charlie Craven.

A Celebration of Life for the Incomparable Dave Whitlock

Learn to tie the Pheasant Tail Nymph with master tier Charlie Craven.

Mending the Line Trailer

Learn to tie the Pheasant Tail Nymph with master tier Charlie Craven.

The Mother's Day Caddis Hatch

Learn to tie the Pheasant Tail Nymph with master tier Charlie Craven.

A Fly Fishing Short Film

Learn to tie the Pheasant Tail Nymph with master tier Charlie Craven.

FF Mag Promo June-July 2023

Learn to tie the Pheasant Tail Nymph with master tier Charlie Craven.

How to Tie Smitherman's Draggin' Nymph

Learn to tie the Pheasant Tail Nymph with master tier Charlie Craven.

Costa Films Presents “Hooked On: Bonefish”

Learn to tie the Pheasant Tail Nymph with master tier Charlie Craven.

Pharmaceutical Pollution Threatens Florida's Shallow-Water Fish

Learn to tie the Pheasant Tail Nymph with master tier Charlie Craven.

Tying Rene Harrop's Hairwing Dun Fly

Learn to tie the Pheasant Tail Nymph with master tier Charlie Craven.

Tying Barr's Damsel Fly

Learn to tie the Pheasant Tail Nymph with master tier Charlie Craven.

Tying the Pheasant Tail Nymph Fly

Fly Fisherman Magazine Covers Print and Tablet Versions

GET THE MAGAZINE Subscribe & Save

Digital Now Included!


Give a Gift   |   Subscriber Services


Buy Digital Single Issues

Magazine App Logo

Don't miss an issue.
Buy single digital issue for your phone or tablet.

Buy Single Digital Issue on the Fly Fisherman App

Other Magazines

See All Other Magazines

Special Interest Magazines

See All Special Interest Magazines

Phone Icon

Get Digital Access.

All Fly Fisherman subscribers now have digital access to their magazine content. This means you have the option to read your magazine on most popular phones and tablets.

To get started, click the link below to visit and learn how to access your digital magazine.

Get Digital Access

Not a Subscriber?
Subscribe Now

Enjoying What You're Reading?

Get a Full Year
of Guns & Ammo
& Digital Access.

Offer only for new subscribers.

Subscribe Now