....................... ......Fly Fishing Yellowstone National Park
Fly Fishing Yellowstone - Pale Morning Dun Spinner
The PMD spinners mate over the water and the males fall dead mostly in the water. The females will deposit their eggs soon after the mating event. These spinner falls take place in the late afternoons and during the early mornings depending on the time of year. Basically, the spinner falls that occur during the cooler weather takes place in the late afternoons. Those that occur after the weather has become hot takes place in the early mornings. They will fall over the same water they hatched from. If they day is warm and the winds are calm, you can look for a heavier spinner fall than you would see on cool, windy days.
Spinners can be difficult to see even when the insects cover the water. Anglers could be on the water right in the middle of a good PMD spinner fall and not even know it was happening. The trout tend to sip the spinners. They provide little evidence of the spinner fall. A skim net will quickly tell you if they are on the water and is the best way to determine if the spinner fall is occurring. Look for the spinners to be in areas where they congregate, such as the slow water below riffles, seams of current and eddies.
Presentation: Our "Perfect Fly" Pale Morning Dun Spinners is a spent wing imitation of the PMD spinners. Usually the females actually touch the water to deposit their eggs but sometimes they drop them from slightly above the water. The trout may take them while they are depositing the eggs but they are more likely to eat them after they die and fall spent into the water. The females die as soon as they have deposited their eggs. It is much easier for the trout to position themselves downstream from the area they deposit their eggs and eat the spinners than it is to chase them around when they are depositing the eggs.
We recommend using a very light tippet and making either an upstream or downstream approach that best provides a drag free presentation. Usually a down stream, or down and across stream presentation, is best for smooth, calmer water. An upstream presentation is best for streams with pocket water. In rough water, you will want to concentrate on the areas the spinners would congregate in, such as the ends of riffles and runs and the heads of pools.