The Rivers of Argentine Patagonia: A Fly Fishing Guide from the Cholila Valley

Argentine Patagonia is not one trout fishery. It is a series of them, strung along the eastern side of the Andes from northern Neuquén down to Tierra del Fuego, and they have less in common than the phrase "Patagonia fly fishing" suggests. A lake-fed river in the Chubut cordillera and a windswept steppe river in Santa Cruz are different pieces of water holding different fish, fished in different ways, reached by different roads. This guide goes region by region from north to south. Most of it is geography and public record, described briefly and sourced. The four waters we fish are described from the bank, because those are the only ones we can speak about from experience.

How the rivers of Patagonia work

The pattern is set by the Andes. Weather arrives from the Pacific, drops most of its water on the western slope and the crest, and what crosses runs east through forest and then out onto the steppe. Some rivers never make it east at all: the Manso, which rises at the foot of Cerro Tronador, drains into the Puelo and on to the Pacific. Most of the rest reach the Atlantic. The other structural fact is the lakes. Along the cordillera, rivers run out of one lake and into the next, and lakes act as reservoirs: they hold flow and temperature steadier than a free-flowing river of the same size. That is why cordillera water often stays clear and cold when rain or snowmelt would have coloured a river elsewhere. None of these fish are native. The native fish were small, and salmonid introductions into South America began in 1904 in Argentina; within a few decades the rivers draining these mountains held wild, self-sustaining populations, which is what swims in them now.

Neuquén: the northern rivers

Northern Neuquén is the historic corridor, the country's oldest and most developed fly fishing culture, centred on Junín de los Andes and San Martín de los Andes. We do not fish here. What follows is the public geography.

The Chimehuín

The Chimehuín rises at Lake Huechulafquen, passes the city of Junín de los Andes, and merges with the Aluminé to form the Collón Curá. It holds brown and rainbow trout and is described as a prime spot for fly fishing.

The Malleo

The Malleo rises in Lake Tromen in the Andes and flows east to join the Aluminé on that river's west bank, in the Huiliches Department of Neuquén. Access is off Provincial Route 23, which meets National Route 234 about 5 km (3 miles) from Junín de los Andes. It is fished for rainbow and brook trout.

The Collón Curá

The Collón Curá begins where the Aluminé and the Chimehuín meet and runs southeast into the Limay, of which it is the principal tributary. Its valley is a designated Important Bird Area, with roughly 200 bird species recorded.

The Aluminé

The Aluminé flows south out of Lake Aluminé, near the town of the same name, and runs about 170 km (105 miles) before becoming a tributary of the Collón Curá near Junín de los Andes.

Río Negro and Bariloche: the Limay, the Manso and the lakes

South of the Neuquén corridor the country changes at Nahuel Huapi. The park surrounds Nahuel Huapi Lake in the foothills of the Patagonian Andes and spans the southwest of Neuquén and the northwest of Río Negro. The Limay begins at the eastern end of that lake and forms the natural border between the two provinces before meeting the Neuquén River to become the Río Negro. It is a working river as well as a fishing one: five dams sit on its course, at Alicurá, Piedra del Águila, Pichi Picún Leufú, El Chocón and Arroyito, and the reservoirs behind them have shortened a river that originally measured about 450 km (280 miles). The Manso runs the other way. It rises at the foot of Cerro Tronador, holds trout and Pacific salmon, and is also used for rafting. This is the busiest part of Andean Patagonia, with a city and an airport, and it sits about two hours north of our valley.

Chubut: the Esquel and Cholila region

This is our country, so this section is written from the bank rather than from a map. We are at Villa Lago Rivadavia, near Cholila, at the north entrance of Los Alerces National Park, which protects more than 259,000 hectares (about 640,000 acres) of Patagonian forest and was declared a UNESCO Natural World Heritage Site in 2017. The park is named for the alerce, the lahuán, a tree that grows slowly and lives a very long time: the specimen known as the Abuelo is around 2,620 years old and 60 m (about 197 ft) tall.

A week here rotates four waters: the Carrileufú, the Río Rivadavia, the Río Arrayanes and the lakes, with a fifth day on a spring creek or on Laguna Larga. The fishing licence and the national park entry fees are included in the rate. We carry rods, reels, flies, leaders and tippet for the day; waders and boots are the one thing to bring, and the packing list covers that.

Two things this region contains that we do not fish. The Trevelin and Futaleufú country to the south, and Arroyo Pescado to the east, are outside our program. The Chubut River is water we can run, but rarely do.

The fish numbers below are our head guide Diego's, and they describe the water around Cholila only. They do not transfer to any other river on this page.

The Carrileufú

The Carrileufú is our home river and it runs past the lodge. It has enough water to cover two or three different sections on separate days depending on conditions, and it is the thread of a larger system: it connects lakes, and the Rivadavia and the Arrayanes carry the same water on. Browns and rainbows here run 12 to 21 inches (30 to 53 cm), with the average fish at 16 to 17 inches (41 to 43 cm) and occasional fish at 22 inches and above, mostly browns. The biggest fish of last season was a 23-inch (58 cm) brown. Diego's read on where they sit: tight to the banks, where most of their food comes from, and on mid-river structure, sunken logs and weed beds especially, which is brown trout water. Big eddies and seams are where the rainbows hold.

The Río Rivadavia

The Rivadavia is inside the national park and is one of the better known rivers in this part of Patagonia, as much for the surroundings as for the fishing. It carries the same lake-fed water as the rest of the system, which is the reason it fishes the way it does.

The Río Arrayanes

The Arrayanes is a shorter stretch, and a day on it starts on the lake before dropping into the river. It is not a long river and it is not a full week's water, but it is a day we recommend including.

The lakes

Lago Cholila, Lago Rivadavia and the rest of the Los Alerces chain are the reservoirs that keep this system steady, and they are fished in their own right. Brook trout run around 14 inches (36 cm) and are found at the spring creek, at tributary mouths and at lake outlets. Landlocked Atlantic salmon run 16 to 20 inches (41 to 51 cm) and are in the system in lower numbers than the trout.

Santa Cruz: the steppe rivers and the big lakes

Further south the forest gives out and the country opens. The Santa Cruz River begins at the shore of the Viedma and Argentino lakes, both of glacial origin and inside Los Glaciares National Park, and runs 385 km (239 miles) east to the Atlantic coast. The Río Gallegos rises at the confluence of the Rubens and the Penitentes, runs about 300 km (186 miles) and reaches the Atlantic through the Gallegos Bay estuary; it is a well known destination for fly fishing for salmonids. Inland from both sits Lago Strobel, on the Strobel plateau in the centre of the province. Its outflow is dry and it is now the centre of an endorheic basin, a closed system with no outlet to the sea. Its waters hold trout, and there is a growing fishing tourism industry around it aimed mainly at international visitors. This is steppe fishing: no forest, a great deal of wind, and a different day out from a cordillera river.

Tierra del Fuego: the Río Grande and sea-run browns

Tierra del Fuego is a different proposition again. The Río Grande runs along the northeast coast of Isla Grande de Tierra del Fuego into the Argentine Sea, and it is the longest and highest-volume river on the island. The city at its mouth has been designated the country's sport trout fishing capital since 2003. The fishery there is built on the sea-run form of the brown trout, which is anadromous: it spends its juvenile stages in fresh water, moves to the sea as an adult, and returns to fresh water to spawn. That is a different fish, in a different province, more than a thousand kilometres from the cordillera rivers described above. It matters because a good deal of what is written online about fly fishing in Argentina is about this water, not about the freshwater rivers of Neuquén, Río Negro and Chubut, and the two get filed under the same search.

Choosing a river

Some of this comes down to what you actually want from the week.

If you want the historic corridor and the deepest guide culture in the country, look north to Neuquén.

If you want lake-fed rivers that hold their flow and clarity when free-flowing water elsewhere colours up or drops, look at the cordillera systems, including ours in Chubut.

If you want big open country, long views and wind, look at the Santa Cruz steppe.

If you want sea-run brown trout, that is Tierra del Fuego, and it is a specialist trip, not a version of the others.

And if you want resident browns and rainbows in clear water with a dry fly, that is the Andean freshwater rivers, north or south. How a lodge sits on its water, how far it drives to fish, and how many rods it takes matter at least as much as the river name, and we have written separately about how to read that before you book.

Getting to the Chubut rivers

Flights run from Buenos Aires to Esquel (EQS), and Esquel is the airport for this valley. From there it is about 1 hour 30 to 1 hour 40 on Route 40 to the lodge, and we arrange that transfer. Two things worth reading before you commit to dates: what a trip like this actually costs, and what to pack, since waders and boots are the gear you have to bring yourself.

The useful version of "Patagonia fly fishing" is narrower than the phrase. Pick the region first, on water type and on how you want to fish, and the rest of the decision gets much simpler. We fish four waters in one valley in Chubut and we have not tried to speak for anyone else's. We also run a three-day ride through the same country, for the days you are not on the water.