Multi-Density vs. Floating Skagit Heads
By: Mark Bachmann
Every successful fly angler has theories about what makes steelhead eat flies. These sea run rainbows come back from the ocean with plenty of accumulated fat in reserve. Some don't have to feed for months. Getting them to eat can be difficult. The angler who can put their fly the closest to each fish's mouth will probably get the most fish to bite, if that fly comes to the fish the right way; at current speed or slower. Winter steelhead have a well deserved reputation of holding next to the bottom of a river, often in deep water where they are difficult to get at with fly fishing gear. This is true much of the time, but not always. Bottom contour, water speed, water temperature and water clarity are main factors that determine where steelhead prefer to hold. Specialized gear can give huge advantages. This is especially true when choosing the right fly line.
Compact changeable tip shooting head fly lines evolved for casting large flies and fishing them deep for winter steelhead that are returning to Pacific Northwest rivers. Since the most work was published by anglers fishing rivers in northern Washington State, these types of lines were designated as Skagit lines. These Skagit lines were designed by individual adventuresome anglers and for several years there was quite a bit of resistance from most fly line companies to supply the needed materials to work with. In the beginning all Skagit Shooting heads were made from a large diameter piece of level floating fly line because that was all that was available to work with. These early taperless lines are now called beer-can Skagit heads. Eventually the Skagit line craze caught on and fly line companies got on board. They added tapers to Skagit heads which made them cast more smoothly and gave them longer flight time.
The Skagit head was designed to be a delivery system for a sinking tip, which enabled anglers to fish at depths where steelhead often held during their migration. Most wild steelhead grew up in riffle water before they left for the Ocean. Upon returning to their native river they also seek riffle water much of the time. This type of water is especially appealing to steelhead during periods when the water is off-color or when human traffic is low. Skagit tackle was specifically designed to fish riffle water that is 2-feet to 6-feet deep with moderate current speed. Floating Skagit heads equipped with 10'-12' of T-11 or T-14 sinking tips are very efficient for fishing in riffles. But during any winter, probably less than half the water that steelhead hold in falls into this category.
Some types of river bottom contours are easy to fish with flies. The easiest water to fish with flies is where current speeds and bottom contours change gradually and predictably. Being able to position yourself on the slow shallow side of the river and having the river gradually get both swifter and deeper toward the other shore is the kind of water almost anyone can fish with a fly rod. A floating Skagit head, the right sinking tip, and good rod/reel outfit are all you need. Multi density lines aren’t necessary for this type of water and are usually a hindrance. But, these kinds of runs are a small percentage of the actual holding water on most rivers, and they are in high demand. so competition often becomes fierce.
Much of most rivers is not easy to fish with conventional swung fly methods. Instead of gradually changing depths and speeds, many pool contours resemble a V-shaped ditch with one leg of the V being shorter than the other. Bottom cobble is often large with steelhead holding around large boulders or bedrock ledges. Fly presentation can get more complicated as water speed quickens and depth increases. Steelhead are often concentrated in soft cushions under layers of faster flows. This makes presentations much more difficult than the softer more predictable flows described above. (The picture above and the illustration below are of the same pool).
In the illustration above black is the stream bed cross-section holding the moving water. Green is the water with lighter green being slower and darker green being faster flows. Blue is air. Water is 800 times denser than air and water molecules move with the least friction against air molecules and with the most friction against the hard stream bed. Steelhead are normally situated in the slowest flows next to the stream bed, which is always the bottom of the river no matter how deep the water is.
In the illustration, each fish is laying approximately the same distance from the bottom and in nearly the same current velocity. Yet the two fish on the right hand side of the illustration are much easier to get at with fly gear than the other two. The ones on the right side require shorter casts which are always easier to control, and they have less water covering them. These two fish are easily reached with a floating Skagit head and normal sinking tip. The fish holding in 3-feet of water can be had with an unweighted fly and a 7.5'S x 2.5'F T-11 M.O.W. tip. The fish holding in 4-feet of water might need 10' of T11 and an unweighted or lightly weighted fly. The fish holding in 6-feet of water is normally at the deeper limits of floating Skagit heads and may need a 10' to 12' T-14 tip and a weighted fly to be reached, but is often easier with a multi-density Skagit head. The main reason being that there is a deeper faster layer of water over the top of it. These deeper higher velocity layers of water tend to move the fly faster than would be interesting to most cold water steelhead. The fish holding in 10-foot deep water is usually out of the realm of floating Skagit heads. All steelhead are beyond the reach of all but the most highly skilled fly anglers using specialized gear such as a F/I/S3/S5 multi-density line equipped with a T-17 tip and weighted fly, or some such tackle.
There are always exceptions to rules. The obvious exceptions are super aggressive fish and very long casts with oblique casting angles to slow a fly down and allow it time to sink. There are also certain kind of mends that aid getting the fly deep. All of these aids use up a lot of time and take very sharp skills. Most fly anglers leave these steelhead for fishers using spinning or casting gear. But fast sinking multi-density Skagit lines are catching on because they work.
Understanding how sinking lines work is a great advantage. Water in rivers is always moving against air at the surface. Normally in water that will hold steelhead, 90% of the current speed is in the top 10% of the water column. A floating Skagit head will stay on the surface unless a sinking tip or weighted fly pulls it under. Therefore in currents where steelhead will hold an unweighted fly fished at the right speed with a floating head and 10'-12' of T-11 and a wide river to allow sink time might sink to 2' to 2.5, which is perfect for water that is 3-feet deep, and maybe okay for water that is 4-feet deep.
But there are often a high percentage of steelhead that are holding in water that is 5' to 7' deep and they are under a layer of fast water that is textured at the surface. This is ordinarily true when a river is very clear. Steelhead often go even deeper into tankier pools when a river becomes very cold during the shortest days of winter. Nor will they move very far for a fly during these conditions. These are the conditions that multi-density Skagit heads were designed for.
Examine the illustration above. The tip end of the F.I.S.T. line is deeper than the other two lines because more of it sinks below the fast surface skin of the water. That allows the tip to be where the water is slower and the whole tip sinks faster. Add a weighted fly and you have a potent combination for fishing deep. Add a cast quartering far downstream and the fly not only fishes deep but also moves slow across the river staying in front of cold lethargic steelhead long enough to annoy them into striking.
Part of the cold clear water equation is not only reaching down to the fish with your fly, but also allowing it to move slow enough to be effective. This often calls for presentations quartering downstream at very oblique angle. This means that very straight 100-foot casts might be needed to reach 40-feet from shore. This approach takes excellent casting skills, good planning and the right fly line. Multi-density lines fly further than floating lines. They are not always the perfect solution for every steelhead situation. But they are often the best line after a few careless boatmen have run all the fish into deep water.