Scuds are one of the first aquatic inverterbraes that can be found in quantity and size in rivers during the spring and early summer.
Fly fisherman like all other fishing enthusiasts have the belief that certain patterns or baits work better in a particular seasons or with certain types of fish. The truth behind some of these generalizations is hard to qualify, but there are a few special practices that make sense and just flat out catch more fish. One of these special patterns is using scud flies in spring and early summer to catch big rainbow trout.
At all levels it makes perfect sense. In many watersheds, scuds can make up as much as 20 percent of a rainbow trout's diets because of their widespread distribution and high densities. Scuds are also one of the first aquatic invertebrates that can be found in rivers in spring and early summer in good numbers and appetizing sizes for fish. Lastly, since scuds are not the strongest of swimmers, and with the runoff or rainy weather associated with spring, lots of these critters get washed from their hiding places to waiting trout.
Scuds are a type of aquatic invertebrate that many people think are a type of freshwater shrimp but in actuality they are not shrimp at all. The difference between these two organisms is that scuds have their 14-leg sets as pairs all along the lower body. Shrimp are different in the fact that they have three distinct sections, and their legs are packed together near the head. For fly anglers, one species of scud is more important that all the rest and that would be the Gammarus species. This scud species is known to hang around shallow water and vegetation/ rocks making them likely targets for hungry rainbows.
When picking the right type of scud pattern to use a few general thoughts should come to mind. First and foremost, fly anglers should always flip a few rocks over in the stream you plan on fishing. Scuds will not be hard to find and it will be beneficial to actually see what the color variations are present in your local waters.
Be sure not to dress the scud fly so heavy that it obstructs the hook point.
If you are at your tying bench and are getting ready for upcoming trip and don't know what colors to tie, start out with a few flies in grey, green and tan. Be sure that you mix in a few darker dubbing patches in the body of the fly because these insects are never monotone in color.
Scud patterns are the one type of fly where size is not absolutely critical. Since these critters are in the rivers most of the year, rainbows don't have to wait for a hatch to feed on them and they do get too finicky about searching out a particular size of bug. Good scud patterns will be between size 12 and 16 and use heavy shank curved fly hooks.
You want a heavy set hook on your flies because you will be fishing on or near bottom most of the time and snags will happen. Thin wire hook straighten easy and after being bent back to shape a time or two they are prone to breaking.
One other consideration to think about with scuds is that the pattern you buy or plan on tying should incorporate some sort of weight to get it down to the bottom. Fish are looking for scuds rolling along the bottom of the river and not high up in the water column. You need to get these patterns down where the fish are looking for them and beads or lead-free weight in the body of flies is a great way to do that.
Lastly be sure that the fly that you pick to fish is tied sparsely! Too many scud flies are dressed so heavy that they obstruct the hook point. Keeping flies orderly and trim will make for more hook ups at the end of your day.
How to Fish 'Em
Rainbow trout can be very aggressive feeders but getting the fly in the strike zone is ideal.
To fish scud patterns for rainbows a 9-foot, 5-weight rod is a great place to start. If you plan on fishing very big, fast flowing waters then size up accordingly so that you can fish the water effectively. The 5 weight, 9-foot rods are perfect for this style of fishing because these rods have the backbone and leverage to set the hook on fish and play them out of deep pools.
A floating flying coupled with abrasion resistant 9-foot leader is also a good starting setup for fishing these flies. Having a reel with a smooth drag system is a must for fishing spring and early summer. Not only are big resident rainbows on the prowl, but if you are fishing a great lake tributary you have the chance of hooking up with a giant steelhead or lake run brown who is going to tear out line on you.
Fishing these flies for rainbows is easy! Find either a deep pool or fishy looking run and cast quartering upstream. As the fly drifts downstream it is very important to mend the fly line to achieve a dead free drift. Rainbows can be very are aggressive feeders but getting the fly in the strike zone so the fish barely have to move to feed is ideal. In many cases fly anglers barely see the indicator move on the take, as fish sip the fly and return to their original position. For this reason when fishing scud patterns make sure to set the hook whenever you see the indicator stop, bob or sink slowly.
Out of all the aquatic insects taking residence in your local rivers and lakes fly anglers need to get to know and understand the importance of scuds to trout. Dead drifting these special flies in spring or early summer will give anglers their best shot at catching a true trophy rainbow.