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Fly Fishing for Argentina's Sea-run Brown Trout

Where one in 50 brown trout is over 20 pounds and fish stack by the hundreds.

Fly Fishing for Argentina's Sea-run Brown Trout

The Rio Grande is one of those rare places where fishing over the course of many decades has been constantly improving. (Jessica DeLorenzo photo)

This article was originally titled "The Silver One" in the Oct/Nov/Dec 2016 issue of Fly Fisherman magazine.

There are many places in the world where the fishing isn’t nearly as good as it used to be. Most places actually.

Steelhead runs in the Pacific Northwest are a shadow of their former glory. Atlantic salmon have been decimated in the U.S. to where wild populations are just barely hanging on in a few streams in Maine. Guides in the Florida Keys have been scratching their heads over a lost generation of bonefish. The oceans are depleted by 90 percent in terms of large gamefish, and you have to walk far and work hard to find a single native Eastern brook trout due to habitat loss and acid mine drainage.

On a planet where fish habitat everywhere seems to be constantly downgraded, and every year opportunities get worse and worse, it stokes your soul to find a river winding through open ranchland that is untouched and unchanged, and both scientific studies and angler results show brown trout fishing is getting better and better with every passing decade.

John Goodall, a Scottish settler who inherited estancias Viamonte and Haberton on the Rio Grande, between 1935 and 1937 stocked tributaries of that river hoping to provide a little recreation. He stocked brown trout from Hamburg, Germany, and rainbow trout from the McCloud River in California into the Ewan, Herminita, Menendez, and other rivers, thinking that some European sport could relieve some of the isolation on the island of Tierra del Fuego at the far end of the South American continent. His hope was to seed wild populations of resident trout similar to other mutton-farming outposts like New Zealand.

Fly Fishing for Argentina's Sea-Run Brown Trout
The last hour of the day (and the first hour) is when 90 percent of the fish on the Rio Grande are landed. The fish are reluctant to look up into the bright midday sun—especially when the water is clear. (Jessica DeLorenzo photo)

Brown and rainbow trout in the tributaries and in the main stem of the Rio Grande used the river’s endless spawning gravel to quickly reproduce and become self-sustaining. By the end of that decade, Goodall was catching the offspring of those original transplants.

But the conditions are harsh in this river—probably the only one of its size this close to Antarctica. The trout population found plenty of spawning and nursery habitat, but there was little forage in the Grande, and the resident trout were skinny and underfed.

In the decade of World War II, outsiders paid little attention to the Tierra del Fuego trout experiment, but in the early 1950s when recreational fishing in North America was exploding and becoming a middle class pastime, rumors spread of some exceptionally large trout in the Rio Grande that locals called una plateada or “the silver one.” Clearly, some of Goodall’s fish had found their way to the ocean and returned.

Outdoor Life writer Joe Brooks journeyed to Maria Behety Ranch three times during the 1950s and found many resident trout, and a few heavily muscled sea-run brown trout. Over the course of those trips, he caught two sea-runs larger than 10 pounds; one was 14 pounds, the other was an 18.5-pound trout that was considered spectacularly large at that time. Curiously, although there were still resident rainbows in the river, none of them migrated to the ocean to become steelhead.

Brooks was ecstatic with what he found in the Rio Grande, but what he was seeing was just the incubation period of what would become the greatest sea-run brown trout fishery in the word. In every decade since his visit, the fishing seems to be getting better as these northern immigrants evolve from one generation to the next.

Genetically they are becoming a larger race of fish as the largest males and females successfully compete for and hold spawning territories.

Each generation is also becoming more adept at finding the most robust food sources in the south Atlantic. In recent decades the tourism industry has also shaped strict catch-and-release regulations through much of the river, and done away with netting in the river and estuary near the town of Rio Grande. Fewer big fish have been culled from the herd, and bigger fish are surviving and reproducing. When Brooks visited, his fish pushing into the high teens was a monster. A 20-pound fish was unfathomable.


Fly Fishing for Argentina's Sea-Run Brown Trout
The Rio Grande is the best place in the world (in January) to catch silver sea trout fresh from the ocean. These ephemeral rarities are aggressive and leap like any fresh steelhead or Atlantic salmon. In a matter of weeks they turn golden yellow with dark spots. (Jessica DeLorenzo photo)

Today, one in 50 fish weighs more than 20 pounds, and with average catch rates of three to six fish per day, the odds of running into big fish like this are pretty good. Fish over 30 pounds are caught every season and the biggest to date is Brian Yamamoto’s 46-inch-long, 25-inch-girth fish that was estimated to weigh more than 40 pounds.

The most recent scientific research shows returns of 45,000 to 70,000 adult sea runs annually to a watershed that stretches 200 kilometers into its headwaters in Chile. When the water is exceptionally high, the fish disperse throughout the watershed, but early in the season (which starts in January) and whenever the water is low, the fish are stacked mostly in the lower pools in Argentina, which are all on the site of the original Menendez Ranch. Quick math says that with 55,000 fish in the river, there is an average of more than 500 fish in each of the 102 named pools.

There are three fishing lodges in the lower river that share 32 beats of this private water in an efficient and effective manner so you can fish closer to the ocean or much farther upriver, depending on the season and how and where the fish are moving. With the assigned beat system, you fish two beats per day, one in the morning and one in the evening, and over the course of a week, you’ll rarely see the same water twice.

The middle of the day is siesta time, when you can catch a few hours of sleep—and you’ll need it badly. Sea runs (like brown trout everywhere) go on the grab in low light, so you’ll need to fish late (until 10 P.M.) on the longest days of the year in January, and get back out there early in the morning. The trout don’t bite well in the middle of the day when the sun is high and shining directly in their eyes, and almost as important, the wind peaks in the middle of the afternoon and subsides in the early morning and late evening.

Near siesta time you’ll fish with longer leaders and small traditional flies like #12 and #14 Blue Charms and Silver Stoats to try and cajole a trout into taking a fly at midday. You’ll make long quartering casts downstream and make small, distinct strips with your left hand while moving steadily through the pool to find a trout willing to play.

Another strategy in high light is to swing/jig a heavy Girdle Bug in the deep broken water where the bank is eroding and sod clumps in a deep slot provide relief from both the sun. You’ll need to land the fly inches from the bank (while casting from the opposite shore), throw a large upstream mend to sink the fly, and then jig it  using short strips so the fly jitterbugs along the bankside cover. When I use this technique I cast, mend, then take a step or two downstream before I hold position and allow the fly to start swimming away from the bank. Taking your step during the sink instead of after the swing gets the fly deeper and keeps the fly near the shoreline cover for longer.

In that last hour before dark it doesn’t pay to work just inches from sod clumps you can’t even see in the failing light. Bring your American steelhead flies for that last 45 minutes because the fish turn aggressive when the sun hits the horizon, and any fly will work as long as it’s big and easy to find. A 3- or 4-inch-long black

Intruder-style fly shows a strong profile in fading light and has great movement in the water—I’ve had great success with Brian Silvey’s steelhead pattern called the Extractor.

Fly Casting with Wind

When you fish the Rio Grande, you’ll arrive at the river in a 4WD pickup or SUV and often park on a football-field size gravel bar. Before turning off the ignition, the guide makes a pilot-like assessment of wind direction and turns the vehicle so it faces directly into the wind. They’ve found that if they park in the other direction, the wind can (and frequently does) rip the doors off the vehicle when the guests get in or out. That’s just a little glimpse at how the omnipresent wind affects every part of this fishing experience. The clarity of the water, the pools you fish (and from which bank), the casts you make, and the tackle you use are all predicated on the wind.

I’ve had many saltwater fishing days canceled completely due to 25 MPH wind forecasts, and when it’s blowing that hard at home, it’s a good day to be in the office. Guides on the Rio Grande describe 25 MPH wind as “a good day for fishing” and they don’t consider it challenging until gusts hit 40 MPH. They have become experts at casting in the wind and more importantly, choosing specific pools that offer partial protection from the wind or at least put the wind at your back.

Fly Fishing for Argentina's Sea-Run Brown Trout
The wind roars across the plains of Tierra del Fuego but with good tackle, and the expertise of the guides using the right pools to put the wind at your back, you can always get your fly in front of the fish. (Jessica DeLorenzo photo)

With a single-handed rod it can be tough to make a complete and effective backcast but with a two-hand rod and a short, heavy Skagit line with a sinking tip you can make many kinds of “extended anchor” Spey casts like a double Spey, snap T, or a Perry poke. The advantage of these casts are that there is very little line in the air, and you use mostly water tension to load the rod. A Snake roll is a good choice too, depending on wind direction. I used a 13-foot G.Loomis NRX 7/8-weight rod with a RIO 550-grain Skagit Max line and a whole set of Skagit MOW tips to fit the water depth and speed in different pools.

That fat, heavy line has momentum to beat the wind when you’re making the cast, and with the wind at your back you can really sail it out there even in gale-force winds. It doesn’t often look pretty but it works. Despite the wind, you can fish successfully here nearly every day of the season.

Timing the Brown Trout Run in Argentina

I like the looks of a big fire-engine red steelhead from the headwaters of the Skeena River almost as much as I like a dime-bright silver fish that has just come from the estuary. Almost, but not quite.

With sea-run brown trout it’s much the same. A dark, heavily spotted brown with a twisted kype is a spectacular fish, especially if it’s a 15-, 20-, or 25-pound trout. Americans can relate to this type of fish—it looks similar to an October fish from the Madison or the Missouri, only much larger. Who wouldn’t want to catch that?

But if you’re going to catch a sea trout, it’s even better to catch a trout that looks and acts as though it just came from the sea. Like an ephemeral mayfly hatch, a “fresh” sea trout with faint spots, reflective flanks, and see-through fins is a special fish that exists just for a few days or a week at most. After more than a week or two in fresh water it assumes a darker, heavily spotted camouflage to match the mottled colors of the river. It begins to look less like an ocean fish, and more like a brown trout.

Fly Fishing for Argentina's Sea-Run Brown Trout
During the day you’ll drift rubber-leg nymphs deep along the sod banks, or swing small traditional salmon flies through the pools. In the morning and evening, large North American steelhead flies bring out the aggressive instincts of these sea trout. (Jessica DeLorenzo photo)

Interestingly, North Americans seem to relish the idea of a big brown trout that looks like . . . well, a brown trout. And having maximum numbers of fish in the river doesn’t sound bad either so the last two months of the season—February and March—are filled mostly with visitors from Canada and the United States looking to catch a lot of really big trout.

Experienced fly fishers from sea-trout countries in Europe, however, don’t come looking for “old” trout that have been in the river for a month or two. In fact, they can be quite snobbish about it. They time their trips for January to coincide with the arrival of the first fresh fish of the season. They aren’t looking for a river that is chock-a-block full of old fish that will soon start spawning. What these chrome-hunters want are shots at that first trickle (and then a flood) of fresh silvery fish that move aggressively to the fly, and leap like Atlantic salmon when hooked. Fresh sea trout don’t just look different, they act different, and they are rare specimens of a natural world that is transient and evolving right before our eyes. Cast a rod in these waters and you are engaged in more than just a hunt for one of the world’s great gamefish . . . you are taking the Southern Hemisphere sacrament of anadromous salmonids. You’re looking for the silver one.

Travel Logistics for Argentina Brown Trout Fishing

There are three lodges that control most of the water on the Rio Grande in Argentina. Estancia Maria Behety and La Villa Maria Behety are both located on the same working mutton ranch on the north side of the lower river; Kautapen is farther upstream and positioned on the opposite (south) bank, but all three lodges fish the same pools and are all located on ranches first settled by Don Jose Menendez on the north and the south sides of the river in 1894 and 1897. The main differences are the guides and the accommodations. I stayed at Maria Behety with a fine group of Americans including Ken and Patti Ferrin (Ken was 83 years old and caught a 22.5-pound sea trout) and the father-son duo of Al and Trevor Clayton, and we all agreed the wine, food, and accommodation were outstanding. The guides were experienced and hardworking. Many of them previously worked at the other lodges on the river before happily settling in at Estancia Maria Behety.

I booked my trip through The Fly Shop at Redding, California ( Professional agencies like this don’t cost you anything, and remove all of the logistical difficulties of arranging international travel. The Fly Shop owner Mike Michalak and his staff have been fishing the Rio Grande for more than 25 years and have firsthand knowledge that will make your trip go as smoothly as possible. For example, one possible hiccup in any trip to the Rio Grande is the separate domestic and international terminals in Buenos Aires. The Fly Shop works with the ladies at LOL Argentina Tourism Solutions so a guide meets you at the arrival gate, helps you with your bags, navigates you to the domestic terminal, and gets you checked in for the domestic flight without a hassle or without speaking a single word of Spanish. Hiccup eliminated. You are taken care of every step of the way.

Ross Purnell is the editor and publisher of Fly Fisherman magzine.

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