Fly Types Explained

A simple breakdown of dry flies, nymphs, and streamers.

Fly selection is one of the most intimidating parts of fly fishing — not because it’s difficult, but because it’s often overexplained.

You do not need hundreds of fly patterns. You do not need to match every insect perfectly. And you do not need to understand entomology to catch fish.

What you do need is a simple understanding of fly types, what they represent, and when fish are likely to eat them.


The Three Main Fly Types

Nearly every fly you will ever use fits into one of three categories:

  • Dry flies (float on the surface)
  • Nymphs (sink below the surface)
  • Streamers (imitate larger prey)

If you understand these three, everything else becomes manageable.


Dry Flies (Surface Feeding)

Dry flies float on the surface and imitate adult insects or other floating food.

They are used when fish are feeding on top — a behavior often called rising.

When to Use Dry Flies

  • You see fish breaking the surface
  • Insects are visibly active
  • Calm or lightly rippled water

Why Beginners Like Dry Flies

  • Takes are visible
  • Timing is intuitive
  • Feedback is immediate

Dry fly fishing is often the most exciting form of fly fishing, but it is not always the most productive.


Nymphs (Subsurface Feeding)

Nymphs sink below the surface and imitate immature insects drifting underwater.

Most aquatic insects spend the majority of their lives underwater, which means most fish feed below the surface most of the time.

When to Use Nymphs

  • Fish are not rising
  • Water is deeper or faster
  • You want consistent results

Why Nymphs Matter

Nymph fishing accounts for a large percentage of fish caught worldwide.

If you learn one fly type well, learn nymphs.


Streamers (Larger Prey)

Streamers imitate baitfish, leeches, or other swimming prey.

Unlike dry flies and nymphs, streamers are often actively moved through the water rather than drifting naturally.

When to Use Streamers

  • Fish are aggressive
  • Water is high or off-color
  • Targeting larger fish

Streamers often catch fewer fish — but the fish they catch tend to be larger.


What Fly Patterns Really Represent

Despite the names and colors, most flies represent general food forms, not exact species.

Fish respond to:

  • Size
  • Shape
  • Movement
  • Position in the water

They respond less to exact color or pattern details than many anglers assume.

This is why simple flies work so well.


Do You Need to “Match the Hatch”?

“Matching the hatch” means selecting flies that closely imitate insects fish are currently feeding on.

While this can matter in specific situations, it is not required for beginners.

Most of the time:

  • Correct depth matters more than exact pattern
  • Natural movement matters more than detail
  • Presentation matters more than color

Understanding how to present a fly correctly matters more than owning the perfect fly.


How Many Flies Do You Actually Need?

Far fewer than you think.

A beginner can fish effectively with:

  • A few dry flies
  • A few nymphs
  • One or two streamers

Mastering when and how to fish them matters more than variety.


Fly Size Explained Simply

Fly size is indicated by a number:

  • Smaller number = larger fly
  • Larger number = smaller fly

For beginners:

  • Mid-range sizes are easiest
  • Extremely small flies are harder to fish
  • Extremely large flies require heavier gear

Balanced fly size helps casting and presentation feel natural.


Matching Fly Type to Rod and Line

Fly types work best when matched to appropriate gear.

For example:

  • Dry flies and nymphs work well on lighter setups
  • Streamers are easier to cast with slightly heavier rods

If you’re unsure how rod choice affects this, see our guide on
fly rod weights explained.


Common Beginner Mistakes with Flies

Many beginners:

  • Carry too many patterns
  • Change flies too often
  • Ignore depth and drift
  • Focus on color instead of presentation

Consistency catches more fish than constant changes.


How Fly Types Fit into the Bigger Picture

Fly type is just one part of the system.

To fish effectively, fly choice must work with:

  • Reading water
  • Casting control
  • Natural presentation

If you haven’t yet, learning
how to read water when fly fishing will improve your results more than buying new flies.


Final Thoughts

Fly selection does not need to be complicated.

If you understand:

  • Surface vs subsurface
  • Small food vs large prey
  • Natural movement vs forced action

You already know enough to catch fish.

The rest comes with time on the water.


Fly fishing, clearly explained.