Over the Rainbow

Argentina's Lago Strobel Is Home To a Thriving Population of Dinosaur-Size Rainbow Trout.

By Pat Ford

February 1, 2021

Photos by Pat Ford

I had just stepped off the de Havilland Twin Otter that brought us from Comodoro Rivadavia, Argentina, to Jurassic Lake Lodge’s private landing strip when my hat blew off. It landed about 30 feet away, and a guest who was leaving the lodge snatched it up and returned it with a smile.

The smile was a premonition of the week to come. I was about to experience an otherworldly rainbow trout fishery, but I first had to make friends with the wind.

I’d known of Jurassic Lake for many years. Its actual name is Lago (Lake) Strobel, and it’s in southern Argentina, about a six-hour drive from El Calafate, the nearest point of civilization. The landscape surrounding the lake is pretty much what one would expect to see on Mars: rough, dry and lifeless. Occasionally, we saw a rabbit or fox or guanaco, but there was very little life except for birds. Lago Strobel is fed by the Río Barrancoso, and there is no outflow. It’s in the middle of nowhere.

In the early ’90s, the land owner decided that the ponds around the lake would be a great place to raise and harvest rainbow trout. Steelhead from the Santa Cruz River and McCloud River rainbow eggs were dumped into the ponds and river, and on a lark, also in the lake, according to the early accounts. Unfortunately, the fish farm plan had a few glitches. The lake and its ponds had no road access or accessible shorelines. There was no way to profitably harvest the trout, much less get them to market, so the plan was abandoned. But the eggs had been planted, and nature took over.

Lago Strobel’s scud and nymph abundance was perfectly suited for rainbow trout, and the hatchlings flourished. With no natural predation, the trout grew to enormous sizes. In 2006, Klaus Frimor and Christer Sjöberg heard rumors of a lost lake with giant rainbow trout and decided to investigate. At the time, Christer owned LOOP Adventures, and Klaus was managing Christer’s lodge on the Río Gallegos. It turned out to be an 11-hour drive from the Río Gallegos to Lago Strobel. There was no habitation on or anywhere near the lake, so Christer and Klaus lived in tents and explored miles of shoreline, including the river mouth. I tracked down Klaus, and he told me they discovered that the fish at the river mouth would eat just about anything, but determining which flies were best for the lake and ponds took some time.

The trout in the lake and river mouth averaged 10 pounds. Christer and Klaus agreed that they should develop an operation to fish Lago Strobel. LOOP Adventures signed a lease with the landowner around the river mouth, and the lodge started as a collection of tents. Eventually, a few rough buildings were set up to house supplies and generators for refrigeration, and the lodge began bringing in anglers from El Calafate. There were no amenities for guests, including plumbing or electricity, but the fishing was off the charts.

Fast forward a dozen years, and Jurassic Lake Lodge, now owned and operated by Carlos Casanello, is as comfortable as it gets, and the fishing is still off the charts. (There’s also another lodge on the lake.)

We flew from the United States to Buenos Aires, where we were met by a lodge agent and escorted to our connecting flight to Comodoro Rivadavia, where we spent the night. The next morning, we were bussed to the local airport for the hourlong flight to Lago Strobel.

It took only a few minutes to drive from the landing strip to the lodge, where we were assigned rooms and offered a snack. We gathered in the dining room and were given the lowdown. Breakfast was at 8 a.m., lunch at 1 o’clock and dinner at 9 p.m. We would fish in groups of two or three and were assigned beats. Guides would join us from 9 a.m. to noon, then from 4 to 8 p.m. All the beats were within walking distance of the lodge, and we could fish on our own at any time.

Barbless hooks were mandatory for our safety, as well as the trout’s. This is no place to take a barbed hook in the eye. The only restriction on flies was no Alaska-style plastic egg rigs.

The lodge is at the mouth of the Barrancoso, which could be fished up to a pool called “The Aquarium” and farther upstream, where the river and pools were considerably smaller. To my surprise, we were told that 90 percent of our fishing would be with floating fly line. We were also told to expect wind — lots of it — and that it wouldn’t affect the fishing much, as long as it blew less than 50 mph. That was a bit intimidating. One day wind speeds reached 70 mph, with gusts to God-knows-what.

I had assembled our group of anglers for the week, so we all knew each other. On the first afternoon, Rodger Glaspey and I headed out to The Aquarium pool after lunch. We had done some research on the most effective flies to bring and settled on an olive woolly bugger-style nymph with a hot pink bead head. We also brought along a new creation called a mop fly. I hadn’t heard of a mop fly, but Rodger had brought a few with him, and the lodge sold them.

The fly is about an inch long and has a sparkled neck and a bead head. The body is made from a piece of mop chenille, which is sold in stores for dusting. The material comes in white, chartreuse and pink. The white mop fly looks like a giant maggot. I picked up three of each and rigged a white one on my 9-foot, 6-inch, 7-weight rod along with a strike indicator on a 12-pound fluorocarbon leader. We didn’t have a guide with us, but Rodger and I were pretty confident we could figure things out.

As we approached the river where it enters the pool, we spotted several double-digit rainbows holding in the current. Rodger swung his olive hot-head through them and immediately hooked up. We were off to the races. That afternoon was undoubtedly the best trout fishing we had ever experienced. Our guide showed up around 4 p.m., and we fished until 8 o’clock. We caught about 35 fish that went more than 10 pounds and five that were in the 17-pound range. We didn’t count anything we thought weighed less than 10 pounds.

Walking back to the lodge, our guide told us he had never seen so many big fish caught in one session from that pool. I had never seen a 17-pound rainbow. Rodger caught a 31-inch rainbow on a dry fly. We were afraid to tell the rest of the guys how lucky we’d been — we figured they wouldn’t believe us anyway.

There are several beats on the river and lake. Moving clockwise from the lodge is a beat known as the “Bay of Pigs,” where you fish off some of the rock formations that surround the lake. The water drops off sharply, and the footing can be tricky, but some truly fat fish patrol the edges, hence the name.

There are two beats at the river mouth — one right, one left. A shallow stretch a short distance away can be easily crossed, so one group waded across and fished the right side of the lake and upstream of the mouth. The guys on the left pretty much fished the mouth and the beach to the left, but also could venture upriver.

The Aquarium pool was another beat, and from there we could also head upriver and sight-fish a smaller stream, which had other pools full of 10-pound rainbows that were easily caught with dry flies and 5-weight rods. We typically fished one beat in the morning and another in the afternoon, rotating through them.

I used a 10-foot, 8-weight rod for the lake and the 7-weight for the river pools. One of my buddies used a LOOP 7-weight switch rod for the lake, which was very effective. The combination of constant wind and current resulted in a chop that made mending with a shorter rod difficult. The extra length helped a lot. Next time I’ll probably bring a switch rod, too.

Most of my fishing was with the mop fly, or a scud or nymph tied below a standard strike indicator. Most of the guys used a giant foam salmon fly with a nymph dropper. For those who wanted to swing flies, a Teeny Mini-Tip sink-tip line worked perfectly, especially at the river mouth. A full intermediate line worked best at the Bay of Pigs if we were using streamers.

We used lighter rods as we went farther upriver. In the higher pools, 4- and 5 weights were fine with light tippets for dry flies. Still, there were plenty of fish going 10-plus pounds.

It was interesting to watch the rainbows move upstream through the shallow sections. They were so big and the water so shallow that their backs were sunburned. We saw lots of fish with scars and wounds on their backs — the result of being exposed to the wind and sun. We saw these fish both upriver and in the lake, so we surmised that they move back and forth continually.

This is a magical fishery, and the holy grail is a 20-pound rainbow, though the fish here fit several loose categories: less than 10 pounds; 10 to 14 pounds, which is basically a thin 30-inch fish; 15 to 19 pounds, a short, very fat or a very long, thin fish; and 20 pounds. These monsters in the latter category were bigger than 30 inches and fat. If we didn’t think oh my God when we first saw it in the net, it wasn’t in the 20-pound class. I caught two, and Rodger caught three, two of which were closer to 25 pounds than 20.

Rodger owns Rainbow King Lodge in Iliamna, Alaska, but neither of us had ever seen anything like these Jurassic rainbows. Our group had a total of nine 20s for the week. That’s exceptional, even for Jurassic Lake. Every one of the 20-pounders was caught on the mop fly.

Wind notwithstanding, the fishing was relatively easy and mostly involved drifting flies with a strike indicator. Every beat had current, except Bay of Pigs, which required casting and retrieving with sink-tip or intermediate lines. There was plenty of current at the river mouth, so we cast up-current and watched the indicator. Strikes could be subtle, or the indicator simply disappeared under water. I started out fishing a white indicator but kept losing it in the foam when the wind kicked up, so I switched to orange. I was concerned that the extra visibility would be a problem — that is, until a 10-pound rainbow ate it.

The guys who used foam flies as indicators caught several fish on them. Every cast could produce anything from a dink to a monster, and they all fought like crazy. Runs went well into the backing, and some of the biggest fish would come completely out of the water more than a dozen times. It was spectacular.

I’ve mentioned the wind here, but not nearly enough. This part of Argentina is geographically flat from the ocean to the Andes Mountains. The wind blows constantly and can reach unbelievable speeds. Normal winds are around 30 mph, which is easily fishable. The river pool is the most protected, as is the river above the mouth; Bay of Pigs is the most exposed. At one point, the wind was steady at 70 mph, with higher gusts. We tried fishing the river mouth, but it was a challenge just to keep upright. Spindrift covered the entire lake, so most of us took the afternoon off.

In hindsight, the wind added to our adventure. We noticed that the lake was calmest at dawn, so Rodger and I would sneak in a little fishing before breakfast. One morning, he caught two of his monsters at the mouth on a mop fly. There’s something about that fly that attracted big fish. It would bob along under the strike indicator, moving with the waves, which could be substantial at the river mouth. Whatever that fly resembles, it was definitely on the big-fish menu.

I was obsessed with landing a 20-pounder, so the mop was pretty much all I used, except the day the fish were going nuts over green scuds. Everyone had a secret fly that worked for them, though we caught the majority of our fish using whatever was on our lines the most.

Our trip was in December 2019, which is early summer in Patagonia. According to the guides, the fishing is outstanding from opening day in October through December, then slows to merely amazing. Their season runs from October to May, and monsters are caught every week of the year. In April, however, the wind dies, and 90 percent of the fishing is with dry flies. I can only imagine 15-plus-pound rainbows on dry flies and 5-weights.

If landing giant rainbows off the beaten path is your idea of adventure, check out Jurassic Lake Lodge at jurassiclake.com. And check out the mop fly at mopflies.com.

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