Increasing your success in mayfly hatches

Joe Riley
As you read this issue of Fishing and Boating News the mayflies of our Tasmanian waters are already listed in the specials on the menu board for our brown and rainbow trout. On clam afternoons the lowland rivers and lakes are already abuzz with red and black spinners, and the mayfly duns float adrift as the intermediate stage of this amazing insect makes its journey from nymph to spinner.

There are plenty of fishing opportunities with the duns and spinners but here are a few tips, most of which are either common knowledge or common sense, but will help lift your success rate when targeting mayfly feeding trout.

1. Match the weather to the water you intend to fish
This is a very common sense statement as most seasoned anglers know that duns generally hatch best on the lakes in overcast weather, however on lowland waters and rivers duns will often hatch in bright calm conditions. Plan your day around the weather. Probably the hardest day to target mayfly feeding fish will be a bright windy day. On days like this target spinner feeders along sheltered shores where the wind is limited by protection from hills and trees.

2. Observe the type of rise and the stage at which the mayflies are being taken
On a given day the progress of a mayfly hatch will see the trout feeding in a number of ways for the mayfly as it makes its emergence. Firstly nymphs will be targeted as they make their way from the weedy depths to the surface to hatch. Early in the day trout will feed eagerly on nymphs but also a variety of lures fished below the surface. As nymphs reach the top of the water they struggle to break free from their sub surface body and emerge as the first stage of their beautiful winged existence. Clues to the type of take are given by the trout as they feed at or near the surface. A flattening of the water surface indicates that the nymph was taken just below or as it reached the surface film, these styles of takes if regularly occurring should be fished with an unweighted nymph or an emerger fly, like a Shuttlecock or Shaving Brush which sits vertically in the water with the body of the fly hanging below the surface. Rises that cause a spray of water in the surface or where you see a snout of the trout poking out to grab a morsel indicate that the offering was above the surface film and was taken accordingly. This is where flies that sit in or above the surface come into their own. Parachute patterns and traditionally hackled duns are the more likely to hit their target in these circumstances.

3. Judge the speed at which the rising fish may be moving
The easiest mayfly feeding trout to catch is one who is preoccupied with mopping up all of the duns in his or her immediate area. These fish will feed to the ignorance of nearly everything that is happening around them once they get the mood to feed in this manner. Alas these fish are a rare occurrence on the more heavily fished waters like Arthurs Lake, but they do happen occasionally. In 2004 I was on Arthurs for the day and was venturing around the top end of the Sand Lake when a lightning and thunder storm forced me to put down the fly rod and take the boat to shore at the entrance to Jones Bay. As the storm passed through the wind dropped out, the lightning and thunder ceased and Jones Bay settled to a glassy calm in the overcast conditions. There were duns hatching by the thousands literally and every fish in the bay had it's snout out of the water chomping down duns like a kid with a happy meal. The next 40 minutes was an experience never to be forgotten as 14 browns up to 4.5 lb grabbed a high floating dun pattern in turn between amongst naturals they were gorging on. This is a memory that will stick with me forever and my pulse still races every time I think about it. The more common experience though is to see the occasional rising fish and to try and cover them well with our representations. Watch these fish closely as what are mistaken as a couple of "oncers" are often the same fish. Trout will track just below the surface at quite a startling pace, watch carefully and time the rises. If you see a rise downwind keep a count and watch for the next rise, if you see a second rise within about 30ft or so, lead the next cast about that distance in front of and along the line indicated by both rises in time for the anticipated path of the trout. This is a very successful technique particularly on Penstock Lagoon where the rainbows can track quite quickly between takes.

4. Learn to make quick accurate casts
I know that fly fishing is an immensely personal pursuit and that to some people competition fly fishing is not an admirable way to practice the art. One of the main lessons I have learned from competition fly fishing is the importance to be able to cast quickly and accurately to a precise point along the path of a rising fish. Whether it be a competition or not the best fly fisher people are those who are gifted with or who have worked hard to develop this talent. When prospecting with flies fish a line that is long enough for you to be able to pick up immediately and cast in a given direction to a rising fish. There is no need to cast to the horizon when you are prospecting with flies, trout can be amazingly ignorant to boats and anglers standing waist deep in water. It is far easier to quickly lengthen a cast than it is to try and shorten a cast while changing direction after picking a long line up. Fish a line that is comfortable to pick up and change direction with quickly towards a rising trout.

5. Fish multi fly leaders
One of the complex beauties about fly fishing is that there are so many variables and seems there is never a black and white answer to any question. There are times, such as in gin clear water, where trout are rising to spinners and a single fly on a fine long leader is the only way to fish. However where you are fishing to trout in most other circumstances there is a huge benefit in fishing a multi fly leader.

In Tasmania you are permitted up to three flies on a single leader and depending on the weather conditions and your casting ability fishing two or three flies provides some tangible benefits. Instead of covering a relatively small area with a single fly, three flies will cover three times the area along the anticipated path of a rising fish or while prospecting for trout. Fishing three flies will also let you offer choices in the style of fly you are fishing, for example on a three fly rig you can fish a high floating dun, parachute or Shuttlecock and a nymph trailing off the point. Regular takes on one particular type of fly will let you modify your set up accordingly to increase the probability of more takes. The down side of course are tangles when a fish is caught on the middle or top dropper however I am always happy to untangle a leader for a trout in the landing net. If you are not confident with a three fly leader practice casting a more over arm style of casting which is opening up your loops and fish with two flies as you are still increasing your chances.
6. Look for sheltered lies where duns or nymphs collect
When a dun hatch is fully underway hundreds of mayfly duns and nymphs drift down the wind as they hatch and dry their wings so they can make a hap hazard flight to shore. Along the way weed patches, rocky outcrops, emergent timber and other obstacles break the effect of the wind into flat calms where these insects get drawn in. Nymphs and duns gather in numbers and these areas and trout are right onto this smorgasboard. Pay attention to these little flat calms as easy pickings will often come from them, even if there are not a lot of duns apparent in them.

7. Watch the birds for clues
Once again this is a simple observation but one that is well worth studying. Both swallows and seagulls are adept at picking duns up off the water as they drift haplessly along waiting for their wings to dry. Watch the birds closely, if the gulls and swallows are flying well above the water they are only searching for a density of duns on the drift. As the birds fly low and put their beaks to the water they are picking morsels off it and trout are likely to be doing a similar thing from below the surface. Also watch the shore for the ravens, these sharp eyed intelligent birds know where the duns will be thickest and don't bother grabbing them on the wing, they will hop along at the bottom of the wind picking the duns off by the hundreds where they gather on the shore. Look for where these birds are gathered in the greatest numbers because this is where the greatest density of duns are. We only do this for fun, but the birds do it for a living, they are far more adept at judging where the food is than we are.

8. Search for risers along the sheltered shore
While it is the nature of mayflies to be carried by the wind to the bottom shore it is always worth a sneaky little look along the sheltered water at the top of the wind. Adult spinners will touch the water to lay eggs and duns will hatch in the lee of the land and all will sit on the water for extended periods of time which makes them easy pickings for trout. A patient approach and watching for rising fish in these flat calms will often produce the goods. Pay attention to what is being taken to achieve the best results.
9. Late in the hatch move down the wind
As the dun hatch progresses more and more food is being carried to the bottom of the wind, this food gathers near the shore so move down the wind to where the food will still be available. If it is a windy day pay careful attention to the foam lines that have developed stringing down the lake, food will be trapped in these and trout will cruise up them picking up easy tit bits. When at the bottom of the wind look for trout still rising along the water adjacent to the shore, often there is plenty of food and a good size fish mopping up.
10. Don't be afraid to move the flies
One thing we have plenty of in the central highlands of Tasmania is wind. Probably the most important points here is in windy weather don't be afraid to move the flies. Dry flies drifted from a boat in windy weather are about as an unnatural presentation as you can get. While the natural nymphs and duns are being buffeted around in the wind, dry flies are anchored to a leader, line, rod and angler and do not appear the least bit natural. Move the flies, anything from a little tweak to a flat out rip them in will work depending on the day. While it does not make sense to pull the flies against the wind this technique obviously preys on the predatory instincts of trout to make them grab the morsel that is about to escape, it works and works well sometimes resulting in smashing takes from eager trout.

All of the above tips are handy to increase your catch rate during the mayfly season that is upon us. While most are common sense they will help you increase your success rate when pursuing trout fixated on a mayfly brunch. As I stated earlier though there are no fixed rules in this complex passion we share and every now and then the most oblique tactic will pay dividends. Great hunting for the mayfly season ahead.

Joe Riley

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