BirdTrout
South Branch Ontonagon River, Michigan
33 mapped river miles, draining 367 square miles, in the Ontonagon subbasin watershed. No gauge stands in it; the nearest is 12.6 miles away, and what this page knows about its temperature is MDNR's classification of the water itself.
50°F and colder is cold, through cold-transitional and cool, to warm above 70°F — the same four bands, breaking at 58, 64 and 70°F, that the app paints. Grey is water nobody has measured.
The nearest live reading
The nearest gauge is 22.8 miles away, at Mineral River Ds Of Native Ck Nr Silver City, Mi — not a reading of this water, but of what the region is doing today. A closer gauge has stopped reporting — USGS carries no water-temperature series for it at all, so no number here comes from it.
The character of the water
A sixth-order river of 33.3 mapped miles, 46.9 feet wide at the median, draining 366.85 square miles before it meets the West Branch Ontonagon River. What MDNR has typed here is warm: 8.9 miles, 27 percent of the length, classed Warm and described as Warm large river with low gradient, spanning river mile 30.0 down to 0.3. The remaining 73 percent carries no class at all, and the classification describes the valley segment rather than the water; no gauge sits on this river, the nearest being 12.6 miles away. The tributary list is substantial — Cisco Branch Ontonagon River at 37.9 miles and Tenmile Creek at 23.4 miles both entering at river mile 33.3, Sucker Creek at 19.5 miles entering at 30.4, Cedar Creek at 12.4 miles at 18.4. Six public land units total 82,049 acres. No trout regulation type, stocking record, access site or launch is recorded for this water.
Thermal classification
MDNR types this water from its valley, not from a thermometer in it. A class, not a temperature — no July mean, because none was measured here.
| Reach | Typed miles | Band | MDNR type |
|---|---|---|---|
| RM 30.0–0.3 | 8.9 | warm | Warm large river · low gradient |
MDNR has classified 8.9 of the 33 miles NHD carries for this stream — 27% of it. Every typed reach carries the same class, warm. The untyped reaches are not warm water — they are water MDNR's inventory does not reach, and the mile ranges above span only the reaches it does.
Questions about this river
- South Branch Ontonagon River fishing report — what it reads right now
- When to fish the South Branch Ontonagon River — hatches, seasons and temperature
- How to get to the South Branch Ontonagon River — access, parking and public land
- South Branch Ontonagon River fishing regulations — season, size and gear by reach
Public land on the river
6 units of public or open-access land touch this river, 82,050 acres in total. Acreage is the whole unit, not the part beside the water.
| Unit | Owner | Acres |
|---|---|---|
| Ontonagon, Michigan Wild and Scenic River | DESG | 34,412 |
| Ottawa National Forest - Bergland Ranger District | United States Forest Service | 22,225 |
| Ottawa National Forest | United States Forest Service | 18,578 |
| Ontonagon Wild And Scenic River | United States Forest Service | 5,253 |
| South Ewen Purchase Unit | U.S. Forest Service | 1,576 |
| Public Water Access Site | Michigan DNR | 6 |
Species
No species records for this water in the files this site reads.
Hatches on this water
42 insects are recorded from the Upper Peninsula, which is the region this river sits in. That is a claim about the region and not a survey of this stream: nobody has recorded which of them has been caught here. Open the river in the app and the hatch panel will narrow it to the ones whose temperature window today's reading is inside.
| Insect | Peak | Water | Size |
|---|---|---|---|
| Fish Eggs Other |
October–January and April | 33–60°F | #10–16 |
| Little Black Stonefly Allocapnia / Capnia spp. |
January–April | 34–46°F | #16–18 |
| Little Brown Stonefly Taeniopteryx / Strophopteryx spp. |
February–April | 38–50°F | #12–16 |
| Blue-Winged Olive Baetis spp. |
March–May and September–November | 38–58°F | #16–22 |
| Blackfly Simulium spp. |
April–June | 40–65°F | #18–22 |
| Cranefly Tipula spp. |
April–June and September–October | 40–65°F | #6–10 |
| Grannom Brachycentrus spp. |
April–May | 48–58°F | #14–16 |
| Green Rock Worm / Green Weenie Rhyacophila spp. |
April–June and September–October | 45–68°F | #10–14 |
| Hendrickson Ephemerella subvaria |
April–May | 45–58°F | #12–14 |
| Alderfly Sialis spp. |
May–June | 52–66°F | #10–14 |
| Caterpillar Lepidoptera larvae |
May–September | 55–75°F | #8–14 |
| Crayfish Orconectes spp. |
May–October | 55–78°F | #4–8 |
| Giant Black Stonefly (Salmonfly) Pteronarcys dorsata |
May–June | 50–62°F | #4–6 |
| Green Sedge Rhyacophila spp. |
May–August | 48–64°F | #12–16 |
And 28 more — the year-round records, mostly: midges, scuds and sculpins, which are in the water every day and are therefore never the news.
Tributaries and watershed
10 named streams meet this one. Confluence miles are above the mouth; the longest twelve are listed.
- West Branch Ontonagon River 49.8 mi · RM 0.0
- Cisco Branch Ontonagon River 37.9 mi · RM 33.3
- Tenmile Creek 23.4 mi · RM 33.3
- Sucker Creek 19.5 mi · RM 30.4
- Cedar Creek 12.4 mi · RM 18.4
- Kostlenick Creek 4.7 mi · RM 21.7
- Farmer Creek 4.6 mi · RM 8.4
- Maple Leaf Creek 3.1 mi · RM 17.5
- Mulligan Creek 2.1 mi · RM 13.2
- Junco Creek 1.9 mi · RM 12.4
South Branch Ontonagon River sits in HUC 8 04020102, the Ontonagon subbasin, and drains 367 square miles, Strahler order 6 at the mouth. 153 NHD reaches carry the name for 33.2 miles in total.
Other water nearby
The closest 6 rivers on this site, straight-line from the middle of this one — not drive time.