Sea Trout Tactics
Ken Morrish May 09, 2023
For anglers who have cut their teeth on steelhead and Pacific salmon, it is important to know that sea trout are warry, more sensitive creatures. Slapping down a four-inch intruder on a short leader followed by a few yards of T14 will scare them straight back to the sea unless the river is darn near blown out. This is a fishery where the angle of delivery is key and where a fly-first presentation pays off. It is a fishery in which wading selectively and carefully and casting quietly can be the difference between success and failure. While the Rio Grande, Gallegos, and Irigoygen all have their special challenges and levels of difficulty, all of the following information is valuable across the sea trout spectrum.
In Pacific salmon, steelhead and Atlantic salmon fishing, there are many occasions when fishing a fly “square” (meaning casting straight across stream, perpendicular to the opposite bank) is both popular and productive. Generally speaking, this is not the case in sea trout fishing. Broadly speaking, strong downstream angles are preferred, making sure that the first thing a sea trout sees is your fly. On runs where you are casting to a high bank where deep water runs beneath it, understanding your angles and what the fish sees is critical, as often time we cast as close to the bank as possible (which is important) but we fail to calculate that we are landing the fly in slow water and that the fastest flow might be 5-to 10-feet from the bank, resulting in a short but strong belly in the line. I constantly see anglers failing to identify this dynamic and suffering as a result. The cure is both simple and a bit tricky. A steeper downstream cast greatly helps reduce the belly but to do so, one must cast a much longer line. Another way of looking at it is to fish a high bank 50 feet from you effectively, you might be better served by casting 75 feet of line from a station further upstream.
My time with master guides on the Rio Gallegos has taught me a great deal about how sensitive sea trout are and how important mindful wading is. The Gallegos is a broad, shallow, low-gradient river, and the giant sea trout that return to it often lack deep lies to hide in when feeling threatened. As a result, they can and typically do react unfavorably to the sound of cleats on stone, plumes of silt moving downstream, and even the most subtle waves created by anglers wading out in favorable casting positions. There are lots of great pieces of water on the Gallegos where the guide will tell you not to get in the water at all or stay to the inside of weed beds or not go deeper than your ankles. The less windy it is, or the lower the water is, the more critical all these precautions become.
Few situations cause a greater sense of futility and despair for sea trout guides than watching an intermediate Spey caster throw snap-t’s and double Speys when the wind is mild. Line tear, or the so-called white mouse of a water-loaded cast, is barbaric to sea trout guides, and for a good reason. That type of noise scares fish. If you want to Spey cast, be sure to work on your single Spey and your snake roll before you land in Argentina. Typically, the wind on Argentina's best sea trout rivers blows downstream. If you hand your guide your two-hander in these conditions, you might see a cast that you have not seen before that is incredibly simple, quiet, and effective. They will slowly draw the line and rod up to the ready position and fire a big roll cast up and across and have the wind carry it downstream. There is no actual set-up or D-loop, and in heavy wind, it is brilliant. This cast is quiet, fast, and it tends to land the fly rather softly. In all sea trout fishing, a soft landing is something to strive for. In the name of casting quietly, being willing to put the two-hander down when and if the wind dies down can also be really helpful.
Leaders and Tippet
Sensitive fish require a delicate approach. Whether you are fishing a floating line, an intermediate or sinking versi-leader or a full-on sink tip, fishing longer leader or tippet than you are accustomed to tends to be a good idea. When fishing a floating line, 12-15 feet is reasonable. When fishing a clear intermediate versi-leader, 6-8 feet of level tippet is advisable. When fishing a straight sink tip, don't be scared of fishing 10 feet of level tippet. Fluorocarbon like RIO Fluoroflex in 0X and 1X has its place, as does the tried and true Maxima in 10, 12, and 15-pound test. Try to fish as heavy a tippet as you can, as you can get broken on the take on 1X like it was 6X. Also, check your leader often as the wind howls and overhand knots happen to the best of anglers in these conditions. Also, note that anglers can often fish through a pool with a floating line or an intermediate versi-leader without significantly disturbing the fish, but as soon as you put on a heavy sink tip, it can change the pool's and the fish’s behavior. I will never forget a guide friend telling me about watching an angler fish through a pool with a sink tip and watching the fish back away from the approaching line/fly and then move back into place once it was gone, and then doing the same thing on subsequent casts. When the wind is soft and the sun is high, the same thing can happen with a floating line and a long leader. They are sensitive creatures with high situational awareness.
Moving the Fly
One distinct difference between traditional steelhead and salmon fishing is that most sea trout guides want their anglers to move the fly. Not all guides want the fly moved the same way, but darn near all of them want it to move. Some might like short, consistent strips, some might like a more erratic retrieve , and some might want the retrieve to change as one progresses through a run in which water speeds change significantly from top to bottom. But most will want movement. When the light drops at the end of the day and the fish become more active, guides will usually opt for a larger darker fly like a leach, a hobo Spey, or a sunray, and with that change of fly, they will likely have a specific retrieve that they will want you to employ. Listen to them. They have their reasons, and they have tried a lot of different tactics over time! Also, when sea trout take, most guides will want you to set the hook immediately, so keep that in mind.
Throughout the season, fishing days are broken into split sessions. After a hearty breakfast, the morning fishing session begins, and you return to the lodge for lunch, the largest meal of the day, around 1 PM. Typically, the beginning of this break coincides with the day's strongest wind, making a long lunch a welcomed reprieve. Lunch is followed by a midday siesta to recharge. The length of the midday break varies slightly over the season, as the point is to get you 8-9 good hours on the water, including at least 30 minutes after the sunset. Some sea trout lodges will fish you into true darkness, so having a headlamp is a good idea. The last hour of the day tends to be among the most productive hours, and it is not uncommon to see pools that looked dead all day long erupt with active fish. After the evening session, there will be a simple dinner and, finally, the challenge of not getting a second wind and staying up too late.
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