Smallmouth Bass
Smallmouth Bass (Micropterus dolomieu) is a freshwater species. The first thing to check: bronze to brassy brown flanks crossed by dark vertical bars, which fade and darken with mood and bottom colour. The look-alike to rule out is Largemouth Bass: the largemouth's jaw extends past the eye and it carries a horizontal stripe instead of vertical bars.
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| Scientific name | Micropterus dolomieu |
|---|---|
| Also called | bronzeback, brown bass, smallie |
| Water | Freshwater |
| Group | Black bass |
| Temperature | Best between 58 and 72 °F, cooler than a largemouth. Smallmouth stay active in colder water than most warmwater species and can be caught through the low 40s. |
How to identify a Smallmouth Bass
- Bronze to brassy brown flanks crossed by dark vertical bars, which fade and darken with mood and bottom colour.
- The upper jaw stops level with the eye, never past it.
- Three dark bars radiate backwards from the eye across the gill cover.
If you would rather not work through a key on a wet deck, photograph the fish and let the app name it — you get the common and the scientific name back, and the record is filed before you release.
Fish it is mistaken for
| Species | How to tell them apart |
|---|---|
| Largemouth Bass | The largemouth's jaw extends past the eye and it carries a horizontal stripe instead of vertical bars. |
| Spotted Bass | A spotted bass has a horizontal row of spots below the lateral line and a tongue tooth patch; the smallmouth has neither. |
Side-by-side comparisons
Read the full entry for Largemouth Bass and Spotted Bass.
Where it lives
Clear, cool, rocky water — river current seams, gravel and boulder shoals, and the rocky points of northern lakes. Far less tolerant of silt and warm still water than a largemouth.
Temperature
Best between 58 and 72 °F, cooler than a largemouth. Smallmouth stay active in colder water than most warmwater species and can be caught through the low 40s.
The conditions that matter
Current and clarity dominate. In rivers, smallmouth set up behind structure on a defined current seam and feed hardest when flow is moving. In lakes, wind pushing onto a rocky point stacks bait and lifts fish off the bottom — wind direction and speed logged against each catch is the pattern most river and lake smallmouth anglers find first.
Global Fishing League records 18 weather and water readings against every catch automatically — tide stage, barometric pressure, water temperature, salinity, dissolved oxygen, chlorophyll, swell, current, moon phase and more, taken at your GPS position at the moment you log the fish. Over a season that turns a hunch about smallmouth bass into a pattern you can read.
See every reading recorded with a catch, or the guides to what each reading means.
Size limits, bag limits and seasons
Size limits, bag limits, slot limits and seasons are set by your state wildlife agency — and for many offshore and migratory species by federal regulators — and on many waters they differ from the statewide rule. They also change between seasons. Check the current regulations for the exact water you are fishing before you keep a fish — we do not republish limits here, because a number that is a season out of date is worse than no number.
What the app does do is make your side of it accurate: every catch carries a length measured from the photograph, a GPS position and a timestamp, exportable if you ever need to show your work for a tournament or a record claim. It is also what a Global Fishing League entry is built from — a record that verifies itself, without publishing where you caught the fish.