Largemouth Bass
Largemouth Bass (Micropterus salmoides) is a freshwater species. The first thing to check: the upper jaw reaches past the back edge of the eye when the mouth is closed. This one mark settles most identifications on its own. The look-alike to rule out is Smallmouth Bass: the smallmouth's jaw stops level with the eye, and its markings run vertically as bars rather than along the flank as a stripe. It is bronze where a largemouth is green.
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| Scientific name | Micropterus salmoides |
|---|---|
| Also called | black bass, bucketmouth, green trout |
| Water | Freshwater |
| Group | Black bass |
| Temperature | Feeds hardest between 65 and 80 °F. Below about 50 °F it becomes lethargic and holds deep; above the mid-80s it moves to shade and deeper water and feeds at the edges of the day. |
How to identify a Largemouth Bass
- The upper jaw reaches past the back edge of the eye when the mouth is closed. This one mark settles most identifications on its own.
- A dark, ragged horizontal stripe runs the length of the flank, broken into blotches rather than drawn as a clean line.
- The spiny front dorsal and the soft rear dorsal are almost separated by a deep notch that nearly reaches the back.
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 |
|---|---|
| Smallmouth Bass | The smallmouth's jaw stops level with the eye, and its markings run vertically as bars rather than along the flank as a stripe. It is bronze where a largemouth is green. |
| Spotted Bass | A spotted bass has rows of dark spots below the lateral line, a rough tooth patch on its tongue, and a jaw that stops at the back of the eye — not past it. |
Side-by-side comparisons
Read the full entry for Smallmouth Bass and Spotted Bass.
Where it lives
Native to the eastern and central United States and stocked almost everywhere else. Holds in warm, weedy, slow water: lake margins, ponds, backwaters, canal systems and the soft edges of reservoirs, usually tight to cover.
Temperature
Feeds hardest between 65 and 80 °F. Below about 50 °F it becomes lethargic and holds deep; above the mid-80s it moves to shade and deeper water and feeds at the edges of the day.
The conditions that matter
Largemouth respond sharply to light and pressure. A falling barometer ahead of a front and heavy cloud cover both tend to push fish out from under cover and onto the feed; the high, bright, still day after the front passes is the notoriously hard one. Water temperature governs the season — logging it against every catch is how you learn the exact band your own water fishes best in.
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 largemouth 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.