In this post I will discuss the basic fundamentals of a nymph rig for catching trout in not only the Guadalupe, but also any tailwater and freestone river that holds trout. You can take this rig anywhere, make a few fly adjustments to match the local bugs, and expect to be successful. This is all due to that a trout’s diet is primarily sub-surface, consuming nymphal forms of mayflies, caddis, midges, and numerous other aquatic insects. Occasionally the fish will rise to the surface during a hatch or spinner fall, but to continue feeding in between hatches the fish must also take advantage of what is right in front of it.
Being that this is the Guadalupe, and a tail-water, and coming from a guide standpoint, the nymph fishing will tend to be the most productive. I can hear the roar of the streamer crowd now, and yes, streamers will work on the Guad. I will discuss streamer fishing for trout in a future post. Dry flies occasionally work too, in the right conditions. But again my experience tells me that nymph fishing is the most effective throughout the day. To cast this nymph rig you do not need a giant heavy rod. A 4 or 5-weight rod with a matched floating, weight forward or double taper line is all you will need. I recommend at least 9-10 foot length rods to help with mending line at a distance.
First thing first, start with a fresh leader. There are usually some big fish in the river and it would be a shame to lose your fish and all your hard work put into your rig on an old, weak leader. With the flows possibly being higher this season I will pick a 9’ tapered leader, but choose your length according to the overall depth of the area you will be fishing. Depending on flow rate and clarity I will choose between a 3x-5x tippet strength. If the water is higher and a little off color then I can get away with the heavier 3x and when it is low and clear I will use smaller tippets like 5x. Carry extra tippet material in those same sizes to extend your leader back to length after fly changes or snags.
Weight and depth are the next two important things and having the right amount can be very critical sometimes. You need just enough weight to get your flies into the strike area quickly, but no too much that you are snagging on the bottom. This will change with the speed of the current and how quick we need the flies to get down. In fast water I will use more weight just to get down quickly in the swifter flows, even if the water is shallow. In slower water use less weight so you’re not dragging an anchor. Carry an assortment of split shot sizes so you can adjust to different conditions. Depth of the river and the depth of the fish will also play a role in your weight selection, too. If you are using a strike indicator then this is an easy adjustment by sliding your indicator up and down your leader to get the right depth. Then adjust weights to make sure your flies are near the strike zone, but not snagging on bottom. If you are not using an indicator then this is done more by feel and experience. With all this being said, depth and weight are two things that I adjust first, and often, before I change fly patterns. On my guide trips I tend to use smaller weights, like size 6 shot, and add and subtract those small amounts to fine tune my speed of getting down.
Fly selection is the next step to rigging, and again, here we are talking about nymph fishing. Most often on the Guadalupe we use a tandem nymph rig, which involves two flies; an attractor and a natural. These two, or more, flies are spaced apart about 15-20” apart in a standard nymph rig. The attractor does exactly what the name implies, attracts attention. I want the fish to definitely see this fly first. It doesn’t always have to be flashy or brightly colored, just enough to get the fish’s attention. The fish may not eat this fly, but now that its eye is looking in our fly’s direction, then along comes the natural fly behind. The natural is the fly we’ve matched to the hatch, or know the fish are eating, and this is also the fly I change most often. The natural is usually smaller than the attractor, and tends to be more bug-like. I also catch more of my fish on a well-matched natural. I could go on and on about exact flies, but that is the challenge of our sport. Besides, local fly shops, like Action Angler, will have the most up to date flies and current bug activity on the river. Asking a few questions and buying a few flies at the local fly shop can go a long way to your success!
This has been a basic overview of a nymph rig for the Guadalupe. There are many other resources out there that dive deeper into the nymph rig with specific knots, indicator preferences, fly selections, and construction, and to become a well-rounded trout angler you should become familiar with all. Nymph fishing may not be as glamorous as a rising fish to a well-placed dry fly, but it can be effective and have its’ own cult following. After all you are still attempting to “match the hatch” and what’s available to the fish.