Michigan Trout Hatch Chart

A Michigan trout hatch chart is useful.

But only if you understand what it can — and cannot — tell you.

Michigan does not have one river.

It has cold Upper Peninsula creeks, groundwater-fed northern Lower Peninsula streams, famous systems like the Au Sable and Pere Marquette, larger rivers, tailwater-influenced reaches and waters that warm and progress at different rates.

So the same insect can appear:

• earlier on one river
• later on another
• earlier on one reach than another
• strongly one year
• weakly the next
• during a different time of day after a weather change

That makes a rigid statewide calendar dangerous.

A better way to use a Michigan trout hatch chart is:

REGION / WATER → SEASONAL WINDOW → FOOD EVENT → LIFE STAGE → TROUT POSITION → PRESENTATION

The chart tells you what might matter.

The trout tell you what matters right now.

For the broader Michigan fishery:

Michigan Trout Fishing

For individual insect biology:

Trout Hatch Library

Michigan Trout Hatch Chart at a Glance

These are broad Michigan seasonal windows, not guaranteed dates for every river.

This is the foundation.

It is not a schedule.

Why Michigan Hatch Timing Cannot Be Reduced to Exact Dates

Hatch timing is driven by more than the month printed on a calendar.

Important variables include:

• water temperature
• recent air temperature
• warming and cooling trends
• river gradient
• groundwater influence
• river branch or reach
• latitude
• insect habitat
• annual weather
• time of day

Local Au Sable reporting provides a perfect example.

In April 2025, Gates Au Sable Lodge described Hendricksons as beginning gradually on the Au Sable and portions of the Manistee, with warmer weather expected to move the hatch through the system. The same report noted BWOs near peak and black caddis approaching. (Gates Au Sable Lodge (Source))

That is how a hatch behaves in the real world:

it progresses.

It does not turn on statewide because your phone changed from April 30 to May 1.

The Michigan Hatch-Chart Rule

Use the calendar in this order.

1. Identify the Water

Au Sable?

Pere Marquette?

Manistee?

Small UP creek?

Larger Lower Peninsula river?

The river matters.

2. Identify the Seasonal Window

What insects are plausible at this point in the year?

3. Observe the Actual Food

Are you seeing:

• mayflies
• caddis
• stoneflies
• midges
• ants
• beetles
• hoppers
• other prey

4. Identify the Lifecycle Stage

A hatch is not a single fly.

For mayflies:

NYMPH → EMERGER → DUN → SPINNER

For caddis:

LARVA → PUPA → EMERGING ADULT → ADULT

5. Watch the Trout

Are they:

• holding near bottom
• feeding mid-column
• bulging beneath the surface
• taking duns
• sipping spinners
• feeding against banks
• ignoring everything on top

6. Choose the Presentation

Only now choose the fly.

That's the Trout Eddy system:

WATER → FOOD → STAGE → TROUT → PRESENTATION → FLY

Winter Michigan Trout Hatches

Winter is not insect-free.

But it is usually a different feeding environment than May or June.

Important foods can include:

• midges
• small stoneflies
• small mayfly nymphs
• occasional Blue-Winged Olive activity during favorable conditions

Most winter insect activity matters below the surface.

That makes:

DEPTH → DRIFT → FISH POSITION

more important than carrying twenty dry flies.

Midges

Midges can remain available when larger insects are relatively inactive.

Useful stages include:

• larva
• pupa
• adult

But surface activity should be observed rather than assumed.

Small Stoneflies

Some small stonefly activity can occur during colder parts of the year.

Nymphs may be more important to trout than obvious adult activity.

Early Spring: BWOs and the Beginning of Dry-Fly Season

Blue-Winged Olives are one of Michigan's important cool-weather mayfly groups.

They can matter during:

• early spring
• cool weather
• cloudy conditions
• later-season periods

Blue-Winged Olive

But seeing BWOs does not automatically mean:

tie on BWO dry.

Fish may be taking:

• nymphs
• emergers
• duns
• spent adults

Your presentation should match the stage trout are actually using.

Hendricksons: Michigan's Classic Spring Progression

The Hendrickson is one of Michigan's defining early-season mayflies.

Hendrickson

On major northern Michigan trout rivers, Hendricksons typically become important during the April–May transition.

But the hatch should be thought of as a progression.

Current and recent Au Sable reporting illustrates that Hendricksons build through sections of a river rather than appearing everywhere simultaneously. (Gates Au Sable Lodge (Source))

Before the Hatch

Fish nymphs.

During Emergence

Consider:

• emergers
• soft hackles
• low-riding patterns

Duns

When trout clearly begin taking upright adults, dry flies become appropriate.

Spinner Falls

Returning adults can create a completely separate feeding event.

If trout refuse your Hendrickson dun late in the evening, they may not be refusing Hendricksons.

They may be eating Hendrickson spinners.

Caddis in Michigan

Caddis are not one short-lived Michigan hatch.

They are a broad food category that can remain important across substantial parts of the season.

Their lifecycle creates several distinct fishing situations:

LARVA

↓

PUPA

↓

EMERGING ADULT

↓

ADULT

That means caddis fishing may include:

• dead-drifted larvae
• ascending pupae
• soft-hackle or emerger presentations
• adult dry flies
• controlled movement where the natural behavior supports it

May: Michigan's Mixed-Hatch Month

May is where simplistic hatch charts begin falling apart.

On Michigan's classic trout rivers, several food events can overlap.

Depending on water and conditions, anglers may encounter combinations of:

• Hendricksons
• caddis
• sulphurs
• Blue-Winged Olives
• March Brown / Borcher-type mayflies
• mahogany or brown mayflies
• stoneflies

The mistake is trying to decide which one “owns May.”

None of them do.

The angler's job is to determine:

What are the fish eating?

Not:

What did the chart tell me they'd eat?

Sulphurs

Sulphurs are an important late-spring and early-summer mayfly event on several Michigan trout rivers.

Sulphur

Again, lifecycle matters:

NYMPH → EMERGER → DUN → SPINNER

Sulphur fishing can become especially interesting during evening periods.

Study the rise form.

Clean surface rise

Likely surface-stage feeding.

Bulge or swirl

Fish may be feeding just beneath the film.

Gentle repetitive sip

Spent adults or another low-riding food may be involved.

The rise is information.

Brown Drakes

Brown Drakes are among Michigan's major early-summer mayfly events.

They can produce intense surface activity but often over comparatively short windows.

Au Sable reporting illustrates just how condition-dependent these events can be: a rapid warm-up in 2018 compressed the period between earlier spring hatches and the arrival of Brown Drakes. (Gates Au Sable Lodge (Source))

That is exactly why annual timing should never be presented as a guaranteed date.

Brown Drake sequence

NYMPH

↓

EMERGER

↓

DUN

↓

SPINNER

Large insects make the event easier to see.

They do not eliminate the need for correct stage and presentation.

Isonychia

Isonychia can provide an important bridge between larger spring mayflies, drakes, Hex and later-season fishing on waters where they are present.

They are especially useful to anglers because they may create opportunities when the river isn't experiencing one of its famous headline hatches.

Useful categories include:

• nymphs
• emergers
• duns
• spinner or spent-adult imitations where appropriate

Do not treat Isonychia timing as uniform statewide.

Check the actual river.

Michigan Hex Hatch

The Hex is Michigan's most famous trout hatch.

*Hexagenia limbata* is a very large burrowing mayfly associated with some of the state's most celebrated after-dark brown-trout fishing.

Hex

The Pere Marquette is known for prolific Drake and Hex events, while the Au Sable has an especially deep Hex tradition. (Trout Unlimited (Source))

But “Michigan Hex hatch” still does not mean one date.

Hex timing can differ by:

• river
• reach
• substrate
• water temperature
• seasonal progression
• annual weather

Hex Nymph

Before obvious surface activity.

Hex Emerger

As insects transition toward the surface.

Hex Dun

Large newly emerged adults riding the water.

Hex Spinner

Returning adults producing another major feeding opportunity.

Night Fishing

Hex fishing commonly extends into darkness.

Know:

• access
• wading route
• exit
• woody structure
• lighting

before nightfall.

The fish are enough of a problem.

You do not need to add “lost in a Michigan swamp” to the evening.

July: The Hatch Calendar Changes

After the giant spring and early-summer events, many anglers assume hatch fishing is mostly over.

It isn't.

The fishing changes.

July can include:

• smaller mayflies
• Tricos
• BWOs
• caddis
• terrestrials
• localized whitefly activity
• lingering or localized Isonychia

The scale of the insects often shrinks.

The importance of:

• precise drift
• leader control
• careful approach
• time of day

often increases.

Tricos

Tricos are one of Michigan's classic technical summer hatches.

The better-known fishing often occurs during morning spinner falls.

That can produce trout feeding rhythmically in small lanes.

Useful flies include:

• tiny Trico duns
• Trico spinners
• spent-wing patterns
• a more visible companion fly where needed

Recent Au Sable reporting shows just how specialized this can become. Gates described size-26 Trico fishing, podded fish and very precise positioning during the 2025 summer progression. (Gates Au Sable Lodge (Source))

Trico fishing rewards

• patience
• careful approach
• accurate casting
• limited unnecessary false casting
• drag control
• correct stage

It does not reward randomly throwing larger flies because the tiny ones are annoying.

Summer Blue-Winged Olives

Small BWOs can continue or return during summer periods on some Michigan waters.

This means a morning can transition through multiple food events.

For example:

TRICO SPINNER → SMALL BWO → GENERAL DRY / DROPPER → TERRESTRIAL

The hatch chart should prepare you for possibilities.

Observation tells you when the transition happens.

Terrestrials

Michigan trout do not stop eating because insects stop emerging from the river.

Summer brings food from the banks.

Important terrestrial categories include:

• ants
• flying ants
• beetles
• hoppers
• other locally available land insects

These become especially useful around:

• grass
• cedar edges
• overhanging vegetation
• undercut banks
• shaded margins

Terrestrial fishing belongs on a Michigan hatch chart even though these insects are not aquatic “hatches” in the strict sense.

The page's job is to help anglers understand trout food events, not win an entomology vocabulary contest.

Flying Ants

Flying ants deserve special attention because a strong ant flight can abruptly change what trout are doing.

These events can be highly weather-dependent.

That means they are almost impossible to schedule precisely from a static annual calendar.

If ants are hitting the river:

fish the event.

Do not keep fishing the morning's mayfly because the chart told you it was Trico season.

Whiteflies

Whitefly or white-mayfly events can matter on portions of some Michigan rivers, especially certain lower-river environments.

They should not be advertised as a universal statewide late-summer hatch.

Treat them as localized.

That's an important distinction between this statewide guide and an individual Water hatch guide.

Fall Michigan Trout Hatches

Fall can still produce meaningful insect activity.

Depending on water, anglers may encounter:

• Blue-Winged Olives
• Isonychia
• small mayflies
• midges
• caddis
• flying ants
• other terrestrials

At the same time, cooling water can make larger-prey presentations relevant again.

That means fall fishing may involve both:

small insect precision

and:

streamer / larger forage fishing

depending on conditions.

Michigan Hatches by Insect Family

A statewide chart becomes easier to use when insects are grouped by how anglers interact with them.

Mayflies

Important Michigan examples include:

• Blue-Winged Olives
• Hendricksons
• Sulphurs
• Brown Drakes
• Isonychia
• Hex
• Tricos
• localized whiteflies
• other regional mayflies

General lifecycle:

NYMPH → EMERGER → DUN → SPINNER

This progression is one of the most important concepts in trout fishing.

Caddisflies

General angling lifecycle:

LARVA → PUPA → EMERGING ADULT → ADULT

Caddis may require:

• subsurface dead drift
• ascending presentation
• soft-hackle movement
• adult dry-fly presentation

depending on stage.

Stoneflies

Stoneflies are especially important as nymphs in many trout systems.

Different species and sizes can appear during different portions of the season.

Do not assume stonefly = giant western salmonfly.

Michigan streams contain a broader range of stonefly food.

Midges

Small but available across cold periods when larger insects may be limited.

They can matter:

• winter
• early spring
• late fall
• other periods depending on water

Terrestrials

Not aquatic hatches, but important seasonal trout food.

Think:

• ants
• beetles
• hoppers
• other bank insects

They belong in a fishing hatch chart because anglers need to know when the trout menu shifts beyond aquatic insects.

The Hatch Lifecycle Matters More Than the Hatch Name

Suppose Hendricksons are present.

That still does not answer what fly to use.

The trout might be eating:

• nymphs near bottom
• emergers beneath the film
• duns on top
• spinners later

All four are “Hendrickson fishing.”

But all four can require different flies and presentations.

That gives us the more useful Trout Eddy rule:

IDENTIFY THE HATCH → IDENTIFY THE STAGE → IDENTIFY WHERE TROUT ARE FEEDING → THEN CHOOSE THE FLY

How to Read Trout Rise Forms During a Hatch

Rise form can help determine the stage fish are eating.

Full rise with obvious surface take

Surface adults may be important.

Bulge without a clean mouth breaking the water

Trout may be taking emergers immediately beneath the surface.

Gentle sipping in slow water

Look closely for:

• spinners
• tiny duns
• ants
• other food sitting low in the film

No rising fish

Do not assume the hatch is irrelevant.

Trout may still be feeding:

• near bottom
• mid-column
• on emerging insects

Start subsurface.

Michigan Hatch Timing by River

A statewide chart should never replace local river information.

Au Sable River

The Au Sable is especially useful for understanding reach-specific hatch progression.

Its Mainstream, Holy Water, North Branch, South Branch and lower river can experience different timing and insect densities.

For detailed Au Sable intelligence:

Pere Marquette River

The Pere Marquette supports important:

• Hendricksons
• caddis
• sulphurs
• drakes
• Hex
• smaller summer mayflies
• terrestrials

Trout Unlimited's Pere Marquette River Lodge profile specifically notes caddis, stoneflies, Hendricksons, sulphurs, Isonychia and prolific Drake/Hex fishing. (Trout Unlimited (Source))

For detailed PM timing and fly selection:

Manistee River

The Manistee has its own hatch progression and should not inherit Au Sable timing merely because both are northern Michigan trout systems.

For its dedicated guide:

Small Northern Michigan and UP Streams

Smaller streams may have:

• different thermal patterns
• different insect communities
• less dramatic headline hatches
• stronger terrestrial dependence
• different timing

Do not use the Au Sable's calendar as a universal Upper Peninsula creek chart.

What Flies Should You Carry for Michigan Trout?

Do not build your box around 100 exact patterns.

Build it around jobs.

Nymphs

For:

• mayflies
• stoneflies
• caddis
• midges

before and during subsurface feeding.

Emergers / Soft Hackles

For insects transitioning through the water column.

Mayfly Duns

For clearly visible surface feeding.

Spinners

For returning spent mayflies.

Caddis Adults

For active surface caddis fishing.

Terrestrials

For:

• ants
• beetles
• hoppers

during the warmer season.

Streamers

For larger prey when conditions and trout behavior make that presentation logical.

Michigan Fly Categories to Shop

This article has legitimate commercial intent.

Dry Flies

Nymphs

Streamer Flies

Trout Flies

The sequence should be:

FOOD EVENT → STAGE → PRESENTATION → FLY CATEGORY → PRODUCT

Not:

HATCH CHART → BUY 75 FLIES

How to Use a Michigan Hatch Chart Before a Trip

Use two layers.

Layer 1 — Seasonal Expectation

Before leaving:

• identify likely insects
• prepare appropriate lifecycle stages
• understand likely times of day
• check the river-specific hatch guide if one exists

Layer 2 — Current Reality

Then verify:

• weather
• local reports
• water conditions
• insects actually present
• rise activity

Michigan DNR's weekly fishing report provides broad current fishing-condition information around the state, but DNR itself notes that conditions can change quickly and recommends checking local fisheries offices, bait shops, outfitters and other local sources for current conditions. (Michigan.gov (Source))

For hatch timing specifically, current local river reports are usually more useful than a statewide government fishing report.

How to Choose a Fly Once You're on the River

Use this sequence.

1. Identify the Water

River and reach.

2. Identify the Likely Seasonal Food

Use the chart.

3. Observe Actual Insects

Ignore the chart if reality disagrees.

4. Identify Lifecycle Stage

Nymph?

Pupa?

Emerger?

Dun?

Spinner?

Adult?

Terrestrial?

5. Watch Trout Position

Bottom?

Mid-column?

Film?

Surface?

Bank?

6. Choose Presentation

Depth.

Drift.

Movement.

Placement.

7. Choose the Fly

Now the pattern matters.

That's the full system:

REGION / WATER → SEASONAL WINDOW → FOOD EVENT → LIFE STAGE → TROUT POSITION → PRESENTATION

When the Hatch Chart Is Wrong

Every hatch chart will eventually be wrong.

Not because the biology disappeared.

Because real rivers vary.

If your chart says:

Hendricksons

but you are seeing:

caddis

fish the caddis.

If the chart says:

Tricos

but trout are eating flying ants:

fish ants.

If the chart says:

Hex

but the hatch has not reached your section yet:

do not spend four hours staring into the darkness because the internet promised bugs.

The river wins every argument with the calendar.

**🐟 EDDY SAYS**

>

“But the hatch chart says Hex.”

>

That's fascinating.

>

There isn't a Hex in the air.

>

Maybe ask the river instead of your screenshot.

Michigan Hatch Charts Are Windows, Not Appointments

This is the most important concept on the page.

A useful hatch chart says:

look for this during this part of the season.

A bad hatch chart says:

this happens on June 17.

The best anglers combine:

seasonal knowledge

with:

current observation

That's what the chart is for.

Not to replace the river.

Official and Current Michigan Resources

Michigan DNR Fishing

https://www.michigan.gov/dnr/things-to-do/fishing

Use DNR for:

• regulations
• trout-water identification
• current statewide fishing information
• fishery management

Michigan DNR Weekly Fishing Report

https://www.michigan.gov/dnr/things-to-do/fishing/weekly

Use it for broad recent statewide fishing conditions. DNR says these reports summarize the previous seven days and recommends local sources when more current water-specific information is needed. (Michigan.gov (Source))

For exact hatch progression, use current reputable local river reports.

Continue Exploring Michigan Trout Hatches

Michigan Trout Fishing

Trout Hatch Library

Michigan Fly Fishing

Blue-Winged Olive

Hendrickson

Sulphur

Hex

Fly Fishing for Trout