How Are Fly Fishing Flies Size?

Fly fishing flies come in different sizes, styles and colors and are designed to imitate the variety of insects found in still or flowing water. The size of a fly fishing fly usually depends on the type of fish being Targeted and the type of water being fished.

Types of Fly Fishing Flies

Fly fishing flies are divided into two categories: wet flies and dry flies. Wet flies are typically weighted or heavily hackled so they can be fished beneath the surface, while dry flies float on the surface to imitate emerging aquatic insects. There are also other types of flies such as terrestrials, streamers, nymphs and salmon/steelhead patterns that can be used depending on the species being Targeted.

Size Considerations

When choosing a size for a fly fishing fly, anglers should consider several factors such as the type of fish being Targeted, the size of their prey, water conditions and visibility. For example, in still waters where visibility is poor, larger flies may be more effective since they will be easier for fish to spot.

On the other hand, in fast-moving rivers or streams where visibility is good, smaller flies may be better since they will be less likely to spook wary trout. Additionally, anglers should take into account the size of their prey when choosing a fly – smaller prey such as midges may require smaller flies whereas larger baitfish may require larger patterns.

Color Considerations

In addition to size considerations when selecting a fly fishing fly, color is also an important factor. Some species such as trout are very sensitive to color changes in their environment while others may not pay much attention to color at all.

Anglers should experiment with different colors until they find one that works best for their Target species and water conditions. Commonly used colors include black, brown, olive and yellow but there are many other bright colors that can be effective under certain conditions.


The size of a fly fishing fly depends on the type of fish being Targeted and water conditions. Anglers should consider both size and color when selecting a pattern for their Target species as these factors can make a big difference in terms of success or failure while out on the water. With careful consideration and experimentation with different sizes and colors anglers can find success regardless of what type of fish they’re Targeting or what type of water they’re fishing in!

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Daniel Bennet