Question 1:
I started fly-fishing last year and so far with limited success. How do you decide which nymph to use when fishing? PT. Lower Hutt.
Answer:
Great question and if we as anglers new all the answers we probably would never get skunked again. There is no short answer to this…there are so many variables but with a little bit of basic knowledge you can { hopefully } load the odds in your favor.
Most of the nymphs you encounter in the river will be some form of Mayfly and are usually divided into four groups…swimmers….burrowers….crawlers….and clingers. They have different characteristics and prefer specific habitats so depending where you are on the river you can offer trout something that they may already be feeding on……if only it were that easy.
Swimmers dislike fast water preferring the slower water which borders the faster flow. They conceal themselves under rocks, logs etc have a skinny rounded profile and in the open use their tails to dart around like little fish.
Burrowers spend most of their time in holes in the river bed and generally feed and hatch at night.They grow to quite a large size and as they grow undergo a number of molts. They are very poor swimmers and are usually taken by trout when they are wriggling their way to the surface to hatch.
Crawlers can be found throughout the river they have quite strong looking legs but without the streamlined shape of swimmers and always have three well defined tails .They live in amongst the rocks and gravel but not usually underneath them so are readily available at any time for hungry trout…just make sure you present the imitation hard on the bottom.
Clingers love fast, oxygenated water and live under the rocks and pebbles in the quicker flowing shallower runs.They have a flat profile to help them cling to rocks etc without getting washed away and normally prefer to feed when the light is poor or at night but trout tend to feed on them as they vacate their hiding places to move into slower water prior to hatching.
I don’t know what you have in your fly-box but it would be a good idea to include some Caddis and Stonefly imitations.One particular fly which is useful on occasions is the ” Toe-biter” which is an excellent representation of the larvae of the Dobson fly and probably one of the larger nymphs you will come across… both Rainbows and Browns will take these.
Like most anglers when nymphing I would usually start with a searching pattern like a Hare and Copper or Pheasant Tail. If I wasn’t getting takes after twenty minutes or so but was sure there were fish in front of me…. then change the fly or experiment with fly size, color or profile…perhaps look at the weight of the bomb…..may be alter the depth…. if this fails….move….the fish obviously don’t like you or your flies and there will probably be some much friendlier { and easier } fish just around the corner.
Question 2: (Images below of TRM resident inmate – Doug Davison from Melbourne on the lower Tongariro)
Dear SWMBO,
Thank you for the offer to explain a basic problem. Your blogs make my day. I have a question I have never been able to get my head around. I have asked other anglers but have never had a satisfactory answer, so I hope your expert guide might explain. The technique for nymphing is to make sure the indicator has a drag free drift. Assuming the leader length and fly weight is right, the woolly indicator should float naturally. Right? Then how do you explain why it is so essential to achieve a natural drift when the current is faster at the top due to natural water hydraulics.
i.e. If I was standing in the river and the top is running at 6 kmph at my crutch, the current might be 4 kmph at my knees, 2 kmph at my shins and almost zero at the bottom where the trout hide. So why are trout attracted to go for a nymph flowing past them at 6 kmph when the natural flow at that lower river bed level might be 1 kmph? To my confused mind it does not make sense? I have stood in strong currents and looked down at my feet where the sand kicked up by my waders does not even move. So why is the natural drift at the speed of the surface so important?
I look forward to your explanation. Tight lines and screaming reels, JT West Auckland
Answer:
This is one that I have also discussed with other anglers over the years and your correct about the flow near the bottom being less than near the surface. During the winter runs fish take advantage of this while migrating up-river to conserve their energy for more important things. The bulk of their food supply is also mainly found on or very near the river bed at this time and because of this they are reluctant to waste energy reserves chasing the odd food item that may be above them.
The importance of maintaining a ” drag free drift” is to allow our flies to sink to the bottom as quickly as possible and then with the aid of mending techniques keep them in the feeding zone as long as possible. We are attempting to imitate the living aquatic nymphs which swim and crawl over the river bed so regardless of the speed of flow near the bottom there would always be movement of some form with the natural.This is why it’s important to use a weighted bomb to help get down to the fish quickly…even then if we didn’t mend and where necessary throw some slack on the water, the line between the indicator and flies would straighten as the indicator is pulled downstream preventing the flies from reaching the feeding trout. Hope this helps.