Au Sable River Fishing Map & Spots (MI)

Hatch outlook

White mayfly (Ephoron)Active window

Typical here: Jul 15 – Sep 30 · core weeks in August — shares its dusk with the White Miller caddis and gets confused with it

dundusk — the whole life cycle plays out in one evening — females mate, fly miles upstream and fall spent within a couple of hours; when the blizzard is too thick, your fly disappears in the crowd — fish the edges of the swarm
spinnerfull dark, same night

Smallmouth set up in feeding lanes like trout and will not move far — accuracy beats distance.

The best conventional surface window of late summer on smallmouth rivers: small white or bone surface plugs and propbaits in the last hour of light, white inline spinners run upstream through the feeding lanes, or a bubble with a White Wulff.

The event happens over sand- and silt-bottom runs with moderate current, feeding lanes below riffles

Blue-Winged OlivesActive window

Typical here: Mar 15 – Oct 24 · multiple broods — peaks early May and mid-June, again Sept–Oct at #20–24

dunmidday, roughly noon–3pm — the first dry-fly action of March and the last of October

Too small to match with hardware — use the schedule instead: midday, and the slow seams it pods fish into; smallest inline spinners and micro-jigs worked slow, or a bubble with an olive soft-hackle.

The event happens over seams, pool tails and flats

Isonychia (Slate Drake)Active window

Typical here: May 15 – Sep 30 · one of the Au Sable 'Big Five' — sporadic all summer rather than a dated blanket

nymphall day in fast water — often emerges by crawling out on shore or rocks — the fishable moment is the fast shoreward swim; fish the nymph with quick twitches toward the bank
dunevenings, sporadically — big fish stay watchful for the bug all summer, which makes it a searching-dry opportunity
spinnerdusk over the riffles — more concentrated action than the emergence itself

The best conventional crossover of the northern-Michigan summer: fish chase this fast-swimming nymph, so #1–2 inline spinners and small minnow plugs ripped through fast runs toward shoreline rocks duplicate it exactly, evenings May through September.

The event happens over fast riffles, boulder pockets and shoreline rocks

White Miller (caddis)Active window

Typical here: Jul 1 – Sep 30 · core weeks late July to mid-August — NOT the same bug as the white mayfly that shares its evenings

pupalate evening into dark — larvae drift extensively before emerging and the surface emergence comes at last light — swing winged wets and actively stripped pupae through dusk
ovipositingdusk into dark — females dive and swim to the bottom in slow water to lay — a sunk white wet fished deliberately is truer than a dry

The prolific, predictable dusk food-form over sand and slow water in the dog days — primarily a night-fisher's event.

A late-summer dusk window on sand-bottom water: small white or pearl inline spinners fished slow near bottom in slow runs imitate the diving egg-layers surprisingly directly; white micro-jigs after dark.

The event happens over slow sand- and weed-bottom runs and pool edges

TricoActive window

Typical here: Jun 15 – Oct 20 · midsummer spinner falls come early; drifting toward mid-morning by fall

dunearly morning
spinnermornings, roughly 6–10am — the event is the fall, not the hatch

Honest answer: hardware can't match a #24 spinner. Fish the same pools with a bubble and a trico spinner on long fluorocarbon, or work micro-jigs through them after the fall ends.

The event happens over slow flats and pool tails

Terrestrials (hoppers, ants, beetles)Active window

Typical here: Jun 1 – Sep 30 · beetles from June, ants mid-June, hoppers mid-July to the end of September

adultwarm afternoons — wind is the delivery mechanism

The most spin-friendly 'hatch' of summer: 1.5–2" surface plugs and small poppers slapped along grassy, windy banks; a bubble-and-hopper rig out-casts any fly rod.

The event happens over grassy and undercut banks

Next on this water

Hendrickson · mayflyApr 15 – May 20 · in ~8 months

Spring black caddis (Grannom) · caddisApr 20 – Jun 30 · in ~8 months

Brown Drake · mayflyMay 15 – Jul 4 · in ~9 months

Sulphurs · mayflyMay 15 – Jul 31 · in ~9 months

Recommendations come from depth structure and seasonal species behavior. Treat them as a starting point, not a guarantee. Contours on this water are approximations. Never use for navigation. Always check local regulations.

Loading depth chart…

Recent catches at Au Sable River

1 angler watching on this water. Exact spots stay private, always.

No shared catches here yet — be the first.Log a catch from the map above and share it to put Au Sable River on the board.

Fishing Au Sable River: what the data says

The Holy Water and beyond. Grayling to Mio, Michigan's most storied trout river. The river tops out around 8 ft. The contours are modeled from the water's real shoreline and maximum depth. Treat them as a rough guide, and never use them for navigation. The season-by-season read for each species follows, from the map's own numbers.

The outline encloses 1,754 acres, worked by 75.4 miles of shoreline. The 12.9 development index tells the story — a convoluted bank whose fishable edge far outruns the acreage. Nothing on this chart breaks 15 ft, which makes the whole surface littoral: weeds, bait and ambush cover everywhere. Call it 28.5 mi long by 2 mi wide at the broadest reach. It sits in Crawford County. Frog Lake (central) sits 10 mi northwest — the closest neighbouring chart.

Brown Trout fishing at Au Sable River

Start shallow in spring: brown trout sit in 1 to 8 ft that time of year. They don't go far with the seasons — 2 to 8 ft covers summer, 1 to 8 ft covers winter. Top water on the chart: Current seam (mile 5.6), a current seam in the 4 ft range, prime in summer. Fish it in after dark and early morning and you'll meet the bite. Throw a spoon at the thermocline or a deep stickbait (night) until the fish tell you otherwise.

Season	Depth	Best window	Start at	Go-to baits
Spring	1 to 8 ft	dawn & dusk	Mio Dam tailrace (7 ft)	Stickbait off planer boards (shallow), Small spoon along mud lines
Summer	2 to 8 ft	night & dawn	Current seam (mile 5.6) (4 ft)	Spoon at the thermocline, Deep stickbait (night)
Fall	1 to 8 ft	dusk & dawn	Mio Dam tailrace (7 ft)	Jerkbait over gravel, Casting spoon
Winter	1 to 8 ft	dawn	Mio Dam tailrace (7 ft)	Jigging spoon, Small stickbait (slow)

Brook Trout fishing at Au Sable River

When the water first warms, brook trout slide up into 1 to 8 ft. There's no big seasonal slide here — summer means 2 to 8 ft, winter 1 to 8 ft. If you only fish one area, make it Current seam (mile 5.6): a current seam around 4 ft that scores prime in spring. In summer the feeding windows fall in early morning and the evening. Keep a small spoon fished deep or a trolled lake-clear wobbler + worm rigged through the warm months.

Season	Depth	Best window	Start at	Go-to baits
Spring	1 to 8 ft	dawn & dusk	Current seam (mile 5.6) (4 ft)	Small inline spinner (gold), Tiny spoon
Summer	2 to 8 ft	dawn & dusk	Current seam (mile 5.6) (4 ft)	Small spoon fished deep, Trolled lake-clear wobbler + worm
Fall	1 to 8 ft	midday & dawn	Current seam (mile 5.6) (4 ft)	Small spoon (orange), Spinner
Winter	1 to 8 ft	dawn	Current seam (mile 5.6) (4 ft)	Small jigging spoon, Tungsten jig + plastic

Rainbow Trout fishing at Au Sable River

Come spring, look for rainbow trout tight to the bank in 2 to 8 ft. Through summer count on 2 to 8 ft; the winter hold is 2 to 8 ft. Start at Current seam (mile 5.6). It's a current seam holding about 4 ft of water and rates prime come spring. Prime time lands in early morning and the evening. A dodger + spoon (deep troll) or a flutter spoon is the honest summer answer here.

Season	Depth	Best window	Start at	Go-to baits
Spring	2 to 8 ft	dawn & dusk	Current seam (mile 5.6) (4 ft)	Inline spinner (silver), Small spoon
Summer	2 to 8 ft	dawn & dusk	Current seam (mile 5.6) (4 ft)	Dodger + spoon (deep troll), Flutter spoon
Fall	2 to 8 ft	dawn & dusk	Current seam (mile 5.6) (4 ft)	Casting spoon, Jerkbait over shoals
Winter	2 to 8 ft	dawn	Current seam (mile 5.6) (4 ft)	Jigging spoon, Tube jig (white)

Rock Bass fishing at Au Sable River

Spring puts rock bass in skinny water — 2 to 8 ft is the zone. Summer fish stay in 2 to 8 ft, and winter fish hold in 2 to 8 ft. Spring rock bass concentrate at Riffle & run (mile 10.0), a prime-rated rock pile around 3 ft. Warm-month bites cluster around the evening. A ned rig (small) or a marabou jig covers the summer program.

Season	Depth	Best window	Start at	Go-to baits
Spring	2 to 8 ft	midday & dawn	Riffle & run (mile 10.0) (3 ft)	1/16 oz jig + grub, Small inline spinner
Summer	2 to 8 ft	dusk	Riffle & run (mile 10.0) (3 ft)	Ned rig (small), Marabou jig
Fall	2 to 8 ft	midday	Riffle & run (mile 10.0) (3 ft)	Small tube jig, Inline spinner
Winter	2 to 8 ft	midday	Riffle & run (mile 10.0) (3 ft)	Tungsten jig + plastic, Small spoon + spike

Notable structure

Au Sable River carries 30 mapped structure features, topping out (or rather bottoming out) at Mio Dam tailrace, about 7 ft down.

Mio Dam tailrace: dam tailrace, around 7 ft
Inside bend (mile 36.2): point, around 7 ft
Outside-bend hole (mile 0.6): creek channel, around 6 ft
Outside-bend hole (mile 3.1): creek channel, around 6 ft
Outside-bend hole (mile 11.8): creek channel, around 6 ft
Outside-bend hole (mile 16.2): creek channel, around 6 ft
Outside-bend hole (mile 18.0): creek channel, around 6 ft
Outside-bend hole (mile 20.2): creek channel, around 6 ft
Outside-bend hole (mile 22.4): creek channel, around 6 ft
Outside-bend hole (mile 25.2): creek channel, around 6 ft
Outside-bend hole (mile 27.1): creek channel, around 6 ft
Outside-bend hole (mile 34.8): creek channel, around 6 ft
Eddy pocket (mile 23.8): eddy pocket, around 6 ft
Current seam (mile 1.9): current seam, around 6 ft

Public access & boat ramps

Camp Ten Bridge — ramp, 20 trailer spots
Connors Flats — ramp, 6 trailer spots
McMasters Bridge — ramp, 10 trailer spots
Mio Pond SFCG — ramp, 10 trailer spots
Parmalee Bridge SFCG — ramp, 6 trailer spots
Stephans Bridge — ramp, 15 trailer spots
Au Sable River Canoe Camp, 8 trailer spots
Burtons Landing SFCG, 20 trailer spots
…plus 2 more mapped sites.

Access data: Michigan DNR — Michigan Boating Access Sites. Confirm conditions and fees locally before you launch.

Au Sable River stocking report

Date	Species	Count	Size
Jun 1	Rainbow trout	5,076	~19.5"
May 20	Rainbow trout	37,117	~18.4"
May 18	Rainbow trout	34,133	~19.1"
May 13	Atlantic salmon	29,498	~19.4"
May 11	Atlantic salmon	7,750	~17"
Apr 29	Rainbow trout	3,100	~20"
Apr 29	Rainbow trout	3,099	~20"
Apr 28	Rainbow trout	5,699	~19.5"

Source: Michigan DNR fish-stocking database, retrieved 2026-08-18.

Au Sable River fishing regulations

Season dates, license requirements, and size and bag limits for Michigan waters are set by the Michigan DNR — and special regulations can apply to Au Sable River specifically, so confirm the current rules before you fish.

Check the official Michigan fishing regulations →

Common questions

How deep is Au Sable River?

Au Sable River is about 8 ft (2 m) deep at its deepest point. The contours here are modeled from the water's real shape and maximum depth, so treat them as a rough guide.

What fish are in Au Sable River?

Anglers target brown trout, brook trout, rainbow trout, rock bass on Au Sable River.

Where is the best fishing spot on Au Sable River?

Current seam (mile 5.6) is the top-rated area: a current seam in about 4 ft of water that rates prime for rainbow trout in spring. Every other rated spot, per species and season, is on the map above.

When is the best time to fish Au Sable River?

For brown trout, the summer bite is best in after dark and early morning. Each species page section below lists the seasonal windows, and the map shows a live NOW badge when you're inside one.

Is Au Sable River stocked with fish?

Yes — per Michigan DNR fish-stocking database records, Au Sable River was most recently stocked Jun 1 with 5,076 rainbow trout. The full stocking history is listed above.

What are the fishing regulations for Au Sable River?

Fishing on Au Sable River is regulated by the Michigan DNR. Check the official Michigan regulations for current license requirements, season dates, and size and bag limits — special regulations can apply to this specific water.

Nearby waters

Frog Lake (central) 10 mi · KP Lake 11 mi · Muskrat Lake 11 mi · Shupac Lake 11 mi · Jones Lake 12 mi · Little Bear Lake 12 mi · Shellenbarger Lake 13 mi · Snyder Lake 13 mi · Bear Lake 13 mi · Tea Lake 14 mi · Moon Lake 14 mi · West Twin Lake 15 mi

See how Au Sable River stacks up: best rainbow trout lakes in Michigan · best brown trout lakes in Michigan · best brook trout lakes in Michigan · best rock bass lakes in Michigan

More water nearby: Crawford County fishing maps (11 charts). Browse all Michigan fishing maps or see every water on DepthScout. How we build these maps. Fish here with a sonar unit that logs? Send us your depth data and we'll improve this chart, credited to you. For fishing guidance only, never navigation.