The Story of Jurassic Lake (Lago Strobel)

May 29, 2025

The origin of this fishery is as remarkable as the trout themselves. In 1989, Julio Citadini—then-owner of Estancia Laguna Verde—introduced approximately 50,000 rainbow trout fingerlings from the Santa Cruz River into the Barrancoso River —Lago Strobel’s only significant tributary. The strain was originally from California’s McCloud River and his stocking efforts on the Barrancoso was intended to establish a recreational fishery.

What followed exceeded even Citadini’s wildest expectations.

For years, it was assumed the stocking effort had failed—until thriving trout began appearing in both the river and Lago Strobel. Lago Strobel, a massive and seemingly barren lake perched high on the Patagonian steppe, proved to be a near-perfect trout factory. The lake’s nutrient-rich waters, abundant scuds, cool temperatures, and lack of natural predators allowed the trout to grow rapidly—and live long. Over time, fish in the 8–10+ pound range became not the exception, but the norm.

Further stocking occurred in 1996 when Citadini received a government grant to develop a commercial fish-harvesting business. However, the exceptional growth rates and size of the trout shifted the focus toward sport fishing.

The unique combination of the lake’s characteristics plus the biannual spawning migrations up the Barrancoso River in the spring and fall contribute to the unparalleled population and size of these wild rainbows.

The term “Jurassic Lake” was coined by Swedish fly fishing pioneer Christer Sjöberg in the early 2000s. Along with fellow angler Klaus Frimor, Sjöberg embarked on an expedition to explore the remote Lago Strobel in southern Argentina. After witnessing the lake’s extraordinary rainbow trout fishery, they sought to keep its location discreet and began referring to it as “Jurassic Lake.” This nickname, inspired by the prehistoric ambiance of the landscape and the colossal size of the trout, quickly gained traction within the angling community and has since become the lake’s most recognized moniker.

Sjöberg, the founder of Loop Tackle and Loop Adventures, played a pivotal role in bringing Lago Strobel to the attention of the global fly fishing community. His efforts not only popularized the lake but also established it as a premier destination for anglers seeking trophy-sized rainbow trout.

Today, one can easily classify Jurassic Lake as the greatest Rainbow Trout fishery in the world. While the fishery is perhaps too young to call it legendary, it will surely gain legendary status. With anglers of average skill hooking roughly 70 fish/day that average 10 pounds on a dry fly, it rightfully should.

If Jurassic is still on your bucket list, know that there are three seasons.

SPRING Oct-Dec Catch rates are the highest due to good flows in the Barrancoso. From the upper beats down to the lake, the river is packed with rainbows and most casts will produce a strike.

SUMMER Jan-Mar Catch rates are the lowest during the summer because the Barrancoso lacks the flows to support a high numbers of big fish. Most of the fishing is done along the lake sure and anglers fishing with persistence can expect around 2-5 hook ups per day on large fish. Although catch rates are low compared to the shoulder seasons, anglers will still land the largest rainbow of their life. Angler focusing on the upper river, however, will catch plenty of 10-17 inch fish.

FALL April-May Catch rates pick back up as the fall rains replenish the Barrancoso and fish once again populate the river. Although catch rates are higher than the summer season and lower than the spring season, the average fish size increases because these fish have had all season to fatten themselves on the scud rich waters of Lago Strobel.